Next Generation Lighting Technologies (LBNL Summer Lecture Series)
Siminovittch, Micheal
2018-04-27
For the past several years, Michael Siminovittch, a researcher in the Environmental Energy Technologies Division of Lawrence Berkeley National Laboratory, has worked to package efficient lighting in an easy-to-use and good-looking lamp. His immensely popular "Berkeley Lamp" has redefined how America lights its offices.
Heat meets light on the nanoscale
Boriskina, Svetlana V.; Tong, Jonathan K.; Hsu, Wei -Chun; ...
2016-06-11
We discuss the state-of-the-art and remaining challenges in the fundamental understanding and technology development for controlling light-matter interactions in nanophotonic environments in and away from thermal equilibrium. Furthermore, the topics covered range from the basics of the thermodynamics of light emission and absorption to applications in solar thermal energy generation, thermophotovoltaics, optical refrigeration, personalized cooling technologies, development of coherent incandescent light sources, and spinoptics.
Rapid prototyping of reflectors for vehicle lighting using laser activated remote phosphor
NASA Astrophysics Data System (ADS)
Lachmayer, Roland; Kloppenburg, Gerolf; Wolf, Alexander
2015-03-01
Bright white light sources are of significant importance for automotive front lighting systems. Today's upper class vehicles mainly use HID or LED as light source. As a further step in this development laser diode based systems offer high luminance, efficiency and allow the realization of new styling concepts and new dynamic lighting functions. These white laser diode systems can either be realized by mixing different spectral sources or by combining diodes with specific phosphors. Based on the approach of generating light using a laser and remote phosphor, lighting modules are manufactured. Four blue laser diodes (450 nm) are used to activate a phosphor coating and thus to achieve white light. A segmented paraboloid reflector generates the desired light distribution for an additional car headlamp. We use high speed milling and selective laser melting to build the reflector system for this lighting module. We compare the spectral reflection grade of these materials. Furthermore the generated modules are analyzed regarding their efficiency and light distribution. The use of Rapid Prototyping technologies allows an early validation of the chosen concept and is supposed to reduce cost and time in the product development process significantly. Therefor we discuss costs and times of the applied manufacturing technologies.
Methodological comparison on OLED and OLET fabrication
NASA Astrophysics Data System (ADS)
Suppiah, Sarveshvaran; Hambali, Nor Azura Malini Ahmad; Wahid, Mohamad Halim Abd; Retnasamy, Vithyacharan; Shahimin, Mukhzeer Mohamad
2018-02-01
The potential of organic semiconductor devices for light generation is demonstrated by the commercialization of display technologies based on organic light emitting diode (OLED). In OLED, organic materials play the role of light emission once the current is passed through. However, OLED do have major drawbacks whereby it suffers from photon loss and exciton quenching. Organic light emitting transistor (OLET) emerged as the new technology to compensate the efficiency and brightness loss encountered in OLED. The structure has combinational capability to switch the electronic signal such as the field effect transistor (FET) as well as light generation. The aim of this study is to methodologically compare and contrast fabrication process and evaluate feasibility of both organic light emitting diode (OLED) and organic light emitting transistor (OLET). The proposed light emitting layer in this study is poly [2-methoxy-5- (2'-ethyl-hexyloxy)-1,4-phenylene vinylene] (MEH-PPV).
NASA-UVa light aerospace alloy and structures technology program
NASA Technical Reports Server (NTRS)
Gangloff, Richard P.; Haviland, John K.; Herakovich, Carl T.; Pilkey, Walter D.; Pindera, Marek-Jerzy; Scully, John R.; Stoner, Glenn E.; Swanson, Robert E.; Thornton, Earl A.; Wawner, Franklin E., Jr.
1991-01-01
The general objective of the NASA-UVa Light Aerospace Alloy and Structures Technology Program was to conduct research on the performance of next generation, light weight aerospace alloys, composites, and associated thermal gradient structures. The following research areas were actively investigated: (1) mechanical and environmental degradation mechanisms in advanced light metals and composites; (2) aerospace materials science; (3) mechanics of materials and composites for aerospace structures; and (4) thermal gradient structures.
Light emitting diodes as a plant lighting source
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bula, R.J.; Tennessen, D.J.; Morrow, R.C.
1994-12-31
Electroluminescence in solid materials is defined as the generation of light by the passage of an electric current through a body of solid material under an applied electric field. A specific type of electroluminescence, first noted by Lossew in 1923, involves the generation of photons when electrons are passed through a p-n junction of certain solid materials (junction of a n-type semiconductor, an electron donor, and a p-type semiconductor, an electron acceptor). Development efforts to translate these observations into visible light emitting devices, however, was not undertaken until the 1950s. The term, light emitting diode (LEDs), was first used inmore » a report by Wolfe, et al., in 1955. The development of this light emitting semiconductor technology dates back less than 30 years. During this period of time, the LED has evolved from a rare and expensive light generating device to one of the most widely used electronic components. The most popular applications of the LED are as indicators or as optoelectronic switches. However, several recent advances in LED technology have made possible the utilization of LEDs for applications that require a high photon flux, such as for plant lighting in controlled environments. The new generation of LEDs based on a gallium aluminum arsenide (GaAlAS) semiconductor material fabricated as a double heterostructure on a transparent substrate has opened up many new applications for these LEDs.« less
Technology Needs for the Next Generation of NASA Science Missions
NASA Technical Reports Server (NTRS)
Anderson, David J.
2013-01-01
In-Space propulsion technologies relevant to Mars presentation is for the 14.03 Emerging Technologies for Mars Exploration panel. The talk will address propulsion technology needs for future Mars science missions, and will address electric propulsion, Earth entry vehicles, light weight propellant tanks, and the Mars ascent vehicle. The second panel presentation is Technology Needs for the Next Generation of NASA Science Missions. This talk is for 14.02 Technology Needs for the Next Generation of NASA Science Missions panel. The talk will summarize the technology needs identified in the NAC's Planetary Science Decadal Survey, and will set the stage for the talks for the 4 other panelist.
NASA-UVA light aerospace alloy and structures technology program
NASA Technical Reports Server (NTRS)
Gangloff, Richard P.; Haviland, John K.; Herakovich, Carl T.; Pilkey, Walter D.; Pindera, Marek-Jerzy; Stoner, Glenn E.; Swanson, Robert E.; Thornton, Earl A.; Wawner, Franklin E., Jr.; Wert, John A.
1990-01-01
The objective of the Light Aerospace Alloy and Structures Technology Program is to conduct interdisciplinary graduate student research on the performance of next generation, light weight aerospace alloys, composites, and associated thermal gradient structures. Individual technical objectives are established for each project. Efforts aim to produce basic understanding of material behavior, monolithic and composite alloys, processing methods, solid and mechanics analyses, measurement advances, and a pool of educated graduate students. Progress is reported for 11 areas of study.
Project Profile: Hydrogen Fuel Cell Mobile Lighting Tower (HFCML)
NASA Technical Reports Server (NTRS)
McLaughlin, Russell
2013-01-01
NASA is committed to finding innovative solutions that improve the operational performance of ground support equipment while providing environment and cost benefits, as well. Through the Hydrogen Fuel Cell Mobile Lighting Tower (HFCML) project, NASA gained operational exposure to a novel application of high efficiency technologies. Traditionally, outdoor lighting and auxiliary power at security gates, launch viewing sites, fallback areas, outage support, and special events is provided by diesel generators with metal halide lights. Diesel generators inherently contribute to C02, NOx, particulate emissions, and are very noisy. In 2010, engineers from NASA's Technology Evaluation for Environmental Risk Mitigation Principal Center (TEERM) introduced KSC operations to a novel technology for outdoor lighting needs. Developed by a team led by Sandia National Laboratory (SNL), the technology pairs a 5kW hydrogen fuel cell with robust high efficiency plasma lights in a towable trailer. Increased efficiency, in both the fuel cell power source and lighting load, yields longer run times between fueling operations while providing greater auxiliary power. Because of the unit's quiet operation and no exhaust fumes, it is capable of being used indoors and in emergency situations, and meets the needs of all other operational roles for metal halide/diesel generators. The only discharge is some water and warm air. Environmental benefits include elimination of diesel particulate emissions and estimated 73% greenhouse gas emissions savings when the hydrogen source is natural gas (per GREET model). As the technology matures the costs could become competitive for the fuel cell units which are approximately 5 times diesel units. Initial operational . concerns included the hydrogen storage tanks and valves, lightning safety/grounding, and required operating and refueling procedures. TEERM facilitated technical information exchange (design drawings, technical standards, and operations manuals) necessary for KSC hydrogen system experts to approve use of the HFCML unit, including initiating the environmental checklist (i.e. exterior lighting waiver due to sea turtles), and development of operations and maintenance instructions. TEERM worked with SNL to establish a bailment agreement for KSC to utilize a Beta unit as part of normal Center Operations for a period of twelve months.
Laser technologies for ultrasensitive groundwater dating using long-lived isotopes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Backus, Sterling
In this phase I work, we propose to construct and demonstrate a 103 nm laser based on resonantly enhanced and phase matched fifth harmonic generation in hollow waveguides driven by a high power, low cost and compact ultrafast fiber laser. (Figure 4) This VUV laser source can potentially produce >100 milliwatts of VUV light at 103 nm with pulse repetition-rates of 100 kHz to 100 MHz, ideal for the above-mentioned applications. This technology is state-of-the-art and potentially compact, fieldable, low-cost, and of broad interest for a variety of science and technology applications. Laser-based VUV sources in the past have exhibitedmore » low repetition rate, low efficiency, low beam quality, and are based on expensive laser sources. Our approch is to combine ultrafast fiber laser drive technology, ultrafast pulses, and our proven waveguide technology, to create a high repetition rate, high average power VUV source for producing high yield metastable Krypton. At KMLabs we have been offering EUV light sources employing the high harmonic generation (HHG) process driven by high-power femtosecond lasers for >5 years now. Recently, we have developed much smaller scale (briefcase size), but still high average power femtosecond fiber laser sources to supply other markets, and create new ones. By combining these new laser sources with our patented waveguide frequency upconversion technology, we expect to be able to obtain >20mW average power initially, with potentially much higher powers depending on wavelength, in an affordable VUV product. For comparison, our current EUV light sources based on ti:sapphire generate an average power of ~5 µW (albeit at shorter 29 nm wavelength), and we are aware of one other supplier that has developed a VUV (112 nm) light source with ~10-20 µW power.« less
Low Mass Printable Devices for Energy Capture, Storage, and Use
NASA Technical Reports Server (NTRS)
Frazier, Donald O.; Singer, Christopher E.; Rogers, Jan R.; Schramm, Harry F.; Fabisinski, Leo L.; Lowenthal, Mark; Ray, William J.; Fuller, Kirk A.
2010-01-01
The energy-efficient, environmentally friendly technology that will be presented is the result of a Space Act Agreement between NthDegree Technologies Worldwide, Inc., and the National Aeronautics and Space Administration's (NASA's) Marshall Space Flight Center (MSFC). The work combines semiconductor and printing technologies to advance lightweight electronic and photonic devices having excellent potential for commercial and exploration applications. Device development involves three projects that relate to energy generation and consumption: (1) a low-mass efficient (low power, low heat emission) micro light-emitting diode (LED) area lighting device; (2) a low-mass omni-directional efficient photovoltaic (PV) device with significantly improved energy capture; and (3) a new approach to building super-capacitors. These three technologies, energy capture, storage, and usage (e.g., lighting), represent a systematic approach for building efficient local micro-grids that are commercially feasible; furthermore, these same technologies, appropriately replacing lighting with lightweight power generation, will be useful for enabling inner planetary missions using smaller launch vehicles and to facilitate surface operations during lunar and planetary surface missions. The PV device model is a two sphere, light trapped sheet approximately 2-mm thick. The model suggests a significant improvement over current thin film systems. For lighting applications, all three technology components are printable in-line by printing sequential layers on a standard screen or flexographic direct impact press using the three-dimensional printing technique (3DFM) patented by NthDegree. One primary contribution to this work in the near term by the MSFC is to test the robustness of prototype devices in the harsh environments that prevail in space and on the lunar surface. It is anticipated that this composite device, of which the lighting component has passed off-gassing testing, will function appropriately in such environments consistent with NASA s exploration missions. Advanced technologies such as this show promise for both space flight and terrestrial applications.
NASA Astrophysics Data System (ADS)
Zhao, Yifan; Du, Jing; Zhang, Jinrun; Shen, Li; Wang, Jian
2018-04-01
Mid-infrared (2-20 μm) light has been attracting great attention in many areas of science and technology. Beyond the extended wavelength range from visible and near-infrared to mid-infrared, shaping spatial structures may add opportunities to grooming applications of mid-infrared photonics. Here, we design and fabricate a reflection-enhanced plasmonic metasurface and demonstrate efficient generation of structured light with the phase helix and intensity helix at 2 μm. This work includes two distinct aspects. First, structured light (phase helix, intensity helix) generation at 2 μm, which is far beyond the ability of conventional spatial light modulators, is enabled by the metasurface with sub-wavelength engineered structures. Second, the self-referenced intensity helix against environmental noise is generated without using a spatially separated light. The demonstrations may open up advanced perspectives to structured light applications at 2 μm, such as phase helix for communications and non-communications (imaging, sensing) and intensity helix for enhanced microscopy and advanced metrology.
Excitonic Materials for Hybrid Solar Cells and Energy Efficient Lighting
NASA Astrophysics Data System (ADS)
Kabra, Dinesh; Lu, Li Ping; Vaynzof, Yana; Song, Myounghoon; Snaith, Henry J.; Friend, Richard H.
2011-07-01
Conventional photovoltaic technology will certainly contribute this century, but to generate a significant fraction of our global power from solar energy, a radically new disruptive technology is required. Research primarily focused on developing the physics and technologies being low cost photovoltaic concepts are required. The materials with carbon-based solution processible organic semiconductors with power conversion efficiency as high as ˜8.2%, which have emerged over the last decade as promising alternatives to expensive silicon based technologies. We aim at exploring the morphological and optoelectronic properties of blends of newly synthesized polymer semiconductors as a route to enhance the performance of organic semiconductor based optoelectronic devices, like photovoltaic diodes (PV) and Light Emitting Diodes (LED). OLED efficiency has reached upto 150 lm/W and going to be next generation cheap and eco friendly solid state lighting solution. Hybrid electronics represent a valuable alternative for the production of easy processible, flexible and reliable optoelectronic thin film devices. I will be presenting recent advancement of my work in the area of hybrid photovoltaics, PLED and research path towards realization electrically injectable organic laser diodes.
NASA Astrophysics Data System (ADS)
Ghosh, Amal K.
2010-09-01
The parity generators and the checkers are the most important circuits in communication systems. With the development of multi-valued logic (MVL), the proposed system with parity generators and checkers is the most required using the recently developed optoelectronic technology in the modified trinary number (MTN) system. This system also meets up the tremendous needs of speeds by exploiting the savart plates and spatial light modulators (SLM) in the optical tree architecture (OTA).
NASA-UVA Light Aerospace Alloy and Structures Technology Program (LA2ST)
NASA Technical Reports Server (NTRS)
Gangloff, Richard P.
1991-01-01
The general objective of the Light Aerospace Alloy and Structures Technology (LA2ST) Program is to conduct interdisciplinary graduate student research on the performance of next generation, light weight aerospace alloys, composites, and associated thermal gradient structures in close collaboration with Langley researchers. Specific technical objectives are established for each research project. Relevant data and basic understanding of material behavior and microstructure, new monolithic and composite alloys, advanced processing methods, new solid and fluid mechanic analyses, measurement advances, and a pool of educated graduate students are sought.
Light-field and holographic three-dimensional displays [Invited].
Yamaguchi, Masahiro
2016-12-01
A perfect three-dimensional (3D) display that satisfies all depth cues in human vision is possible if a light field can be reproduced exactly as it appeared when it emerged from a real object. The light field can be generated based on either light ray or wavefront reconstruction, with the latter known as holography. This paper first provides an overview of the advances of ray-based and wavefront-based 3D display technologies, including integral photography and holography, and the integration of those technologies with digital information systems. Hardcopy displays have already been used in some applications, whereas the electronic display of a light field is under active investigation. Next, a fundamental question in this technology field is addressed: what is the difference between ray-based and wavefront-based methods for light-field 3D displays? In considering this question, it is of particular interest to look at the technology of holographic stereograms. The phase information in holography contributes to the resolution of a reconstructed image, especially for deep 3D images. Moreover, issues facing the electronic display system of light fields are discussed, including the resolution of the spatial light modulator, the computational techniques of holography, and the speckle in holographic images.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Davis, Lynn; Arquit Niederberger, Anne
Abstract— Lighting systems have the ability to transform the economic and educational infrastructure of disadvantaged communities, and eradicating “light poverty” has become one of the primary goals of the International Year of Light 2015. Solid-state lighting (SSL) technology, based on light-emitting diode (LED) light sources, has emerged as the next generation of lighting technology, with a current global market penetration of roughly 5%. This paper will report on recent research on understanding SSL lighting system reliability (failure modes, environmental stressors, electrical power quality); discuss the implications of SSL technology reliability for providing lighting services; and suggest practical approaches to ensuremore » SSL reliability to benefit humanity. Among the key findings from this work is that LED sources can be extremely reliable, withstanding a broad range of environmental stresses without failure. Nonetheless, SSL lighting systems can have a negative impact on electrical power reliability, as well as on the affordability of lighting services, without attention to the quality of the accompanying power infrastructure. It is therefore critical to ensure that the performance of the power supply electronics used in lighting systems is matched to the quality of the power source, when evaluating energy efficient lighting choices.« less
Kent G. Apostol; Kas Dumroese; Jeremy Pinto; Anthony S. Davis
2015-01-01
Light-emitting diode (LED) technology shows promise for supplementing photosynthetically active radiation (PAR) in forest nurseries because of the potential reduction in energy consumption and an ability to supply discrete wavelengths to optimize seedling growth. Our objective was to examine the effects of light spectra supplied by LED and traditional high-pressure...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-04-25
... cars and light trucks have been inspected by scanning the vehicle's computerized second generation on... technology (MY 1995 and earlier cars and light trucks and MY 2006 and earlier heavy trucks). III. What... light duty vehicles and trucks up to 8,500 pounds GVWR, and includes vehicles operating on all fuel...
NASA-UVA Light Aerospace Alloy and Structures Technology Program (LA2ST)
NASA Technical Reports Server (NTRS)
Scully, John R.; Shiflet, Gary J.; Stoner, Glenn E.; Wert, John A.
1996-01-01
The NASA-UVA Light Aerospace Alloy and Structures Technology (LA2ST) Program was initiated in 1986 and continues with a high level of activity. The objective of the LA2ST Program is to conduct interdisciplinary graduate student research on the performance of next generation, light-weight aerospace alloys, composites and thermal gradient structures in collaboration with NASA-Langley researchers. Specific technical objectives are presented for each research project. We generally aim to produce relevant data and basic understanding of material mechanical response, environmental/corrosion behavior, and microstructure; new monolithic and composite alloys; advanced processing methods; new solid and fluid mechanics analyses; measurement and modeling advances; and a pool of educated graduate students for aerospace technologies. Three research areas are being actively investigated, including: (1) Mechanical and environmental degradation mechanisms in advanced light metals, (2) Aerospace materials science, and (3) Mechanics of materials for light aerospace structures.
DELTA-DIESEL ENGINE LIGHT TRUCK APPLICATION Contract DE-FC05-97OR22606 Final Report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hakim, Nabil Balnaves, Mike
2003-05-27
DELTA Diesel Engine Light Truck Application End of Contract Report DE-FC05-97-OR22606 EXECUTIVE SUMMARY This report is the final technical report of the Diesel Engine Light Truck Application (DELTA) program under contract DE-FC05-97-OR22606. During the course of this contract, Detroit Diesel Corporation analyzed, designed, tooled, developed and applied the ''Proof of Concept'' (Generation 0) 4.0L V-6 DELTA engine and designed the successor ''Production Technology Demonstration'' (Generation 1) 4.0L V-6 DELTA engine. The objectives of DELTA Program contract DE-FC05-97-OR22606 were to: Demonstrate production-viable diesel engine technologies, specifically intended for the North American LDT and SUV markets; Demonstrate emissions compliance with significant fuelmore » economy advantages. With a clean sheet design, DDC produced the DELTA engine concept promising the following attributes: 30-50% improved fuel economy; Low cost; Good durability and reliability; Acceptable noise, vibration and harshness (NVH); State-of-the-art features; Even firing, 4 valves per cylinder; High pressure common rail fuel system; Electronically controlled; Turbocharged, intercooled, cooled EGR; Extremely low emissions via CLEAN Combustion{copyright} technology. To demonstrate the engine technology in the SUV market, DDC repowered a 1999 Dodge Durango with the DELTA Generation 0 engine. Fuel economy improvements were approximately 50% better than the gasoline engine replaced in the vehicle.« less
NASA Astrophysics Data System (ADS)
Rubinsztein-Dunlop, Halina; Forbes, Andrew; Berry, M. V.; Dennis, M. R.; Andrews, David L.; Mansuripur, Masud; Denz, Cornelia; Alpmann, Christina; Banzer, Peter; Bauer, Thomas; Karimi, Ebrahim; Marrucci, Lorenzo; Padgett, Miles; Ritsch-Marte, Monika; Litchinitser, Natalia M.; Bigelow, Nicholas P.; Rosales-Guzmán, C.; Belmonte, A.; Torres, J. P.; Neely, Tyler W.; Baker, Mark; Gordon, Reuven; Stilgoe, Alexander B.; Romero, Jacquiline; White, Andrew G.; Fickler, Robert; Willner, Alan E.; Xie, Guodong; McMorran, Benjamin; Weiner, Andrew M.
2017-01-01
Structured light refers to the generation and application of custom light fields. As the tools and technology to create and detect structured light have evolved, steadily the applications have begun to emerge. This roadmap touches on the key fields within structured light from the perspective of experts in those areas, providing insight into the current state and the challenges their respective fields face. Collectively the roadmap outlines the venerable nature of structured light research and the exciting prospects for the future that are yet to be realized.
Low Mass Printable Devices for Energy Capture, Storage, and Use for Space Exploration Missions
NASA Technical Reports Server (NTRS)
Frazier, Donald O.; Singer, Christopher E.; Ray, William J.; Fuller, Kirk A.
2010-01-01
The energy-efficient, environmentally friendly technology that will be presented is the result of a Space Act Agreement between -Technologies Worldwide, Inc., and the National Aeronautics and Space Administration s (NASA s) Marshall Space Flight Center (MSFC). This work combines semiconductor and printing technologies to advance lightweight electronic and photonic devices having excellent potential for commercial and exploration applications, and is an example of industry and government cooperation that leads to novel inventions. Device development involves three energy generation and consumption projects: 1) a low mass efficient (low power, low heat emission) micro light-emitting diode (LED) area lighting device; 2) a low-mass omni-directional efficient photovoltaic (PV) device with significantly improved energy capture; and 3) a new approach to building supercapacitors. These three technologies - energy capture, storage, and usage (e.g., lighting) - represent a systematic approach for building efficient local micro-grids that are commercially feasible; furthermore, these same technologies will be useful for lightweight power generation that enables inner planetary missions using smaller launch vehicles and facilitates surface operations. The PV device model is a two-sphere, light-trapped sheet approximately 2-mm thick. The model suggests a significant improvement over current thin film systems. All three components may be printed in line by printing sequential layers on a standard screen or flexographic direct impact press using the threedimensional printing technique (3DFM) patented by NthDegree. MSFC is testing the robustness of prototype devices in the harsh space and lunar surface environments, and available results will be reported. Unlike many traditional light sources, this device does not contain toxic compounds, and the LED component has passed stringent off-gassing tests required for potential manifesting on spacecraft such as the International Space Station. Future exploration missions will benefit from "green" technology lighting devices such as this, which show great promise for both terrestrial use and space missions.
NASA-UVA light aerospace alloy and structures technology program (LA(sup 2)ST)
NASA Technical Reports Server (NTRS)
Gangloff, Richard P.; Haviland, John K.; Herakovich, Carl T.; Pilkey, Walter D.; Pindera, Marek-Jerzy; Scully, John R.; Starke, Edgar A., Jr.; Stoner, Glenn E.; Thornton, Earl A.; Wawner, Franklin E., Jr.
1992-01-01
The general objective of the Light Aerospace Alloy and Structures Technology (LA(sup 2)ST) Program is to conduct interdisciplinary graduate student research on the performance of next generation, light weight aerospace alloys, composites, and thermal gradient structures in collaboration with Langley researchers. Specific technical objectives are established for each research project. We aim to produce relevant data and basic understanding of material behavior and microstructure, new monolithic and composite alloys, advanced processing methods, new solid and fluid mechanics analyses, measurement advances, and critically, a pool of educated graduate students for aerospace technologies. Four research areas are being actively investigated, including: (1) Mechanical and Environmental Degradation Mechanisms in Advanced Light Metals and Composites; (2) Aerospace Materials Science; (3) Mechanics of Materials and Composites for Aerospace Structures; and (4) Thermal Gradient Structures.
NASA Astrophysics Data System (ADS)
Johnson, D. R.; Marcus, A. A.; Campbell, R. S.; Sommers, P.; Skumatz, L.; Berk, B.; Petty, P.; Eschbach, C.
1981-10-01
A solid state ballast (SSB), which improves the efficiency of fluorescent lights, is described. The first generation of solid state electronic ballasts was developed and the technology was transferred to the private sector. The opportunities for rapid dissemination of this technology into the marketplace is examined. Product characteristics and their influence on the commercialization of the SSB, a description of the technology delivery system presently used by the ballast industry, an analysis of the market for SSB, and identification of some high leverage opportunities to accelerate the commercialization process are included.
Projection display technology and product trends
NASA Astrophysics Data System (ADS)
Kahn, Frederic J.
1999-05-01
Major technology and market trends that could generate a 20 billion dollar electronic projector market by 2010 are reviewed in the perspective of recent product introductions. A log linear analysis shows that the light outputs of benchmark transportable data video projectors have increased at a rate of almost 90 percent per year since 1993. The list prices of these same projectors have decreased at a rate of over 40 percent per year. The tradeoffs of light output vs. resolution and weight are illustrated. Recent trends in projector efficacy vs. year are discussed. Lumen output per dollar of list price is shown to be a useful market metric. Continued technical advances and innovations including higher throughput light valve technologies with integrated drivers, brighter light source, field sequential color, integrated- and micro-optical components, and aerospace materials are likely to sustain these trends. The new technologies will enable projection displays for entertainment and computer applications with unprecedented levels of performance, compactness, and cost-effectiveness.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Spindler, Jeffrey; Kondakova, Marina; Boroson, Michael
2016-05-25
In this work we describe the technology developments behind our current and future generations of high brightness OLED lighting panels. We have developed white and amber OLEDs with excellent performance based on the stacking approach. Current products achieve 40-60 lm/W, while future developments focus on achieving 80 lm/W or higher.
NASA Astrophysics Data System (ADS)
Li, W.; Su, Y.; Harmon, T. C.; Guo, Q.
2013-12-01
Light Detection and Ranging (lidar) is an optical remote sensing technology that measures properties of scattered light to find range and/or other information of a distant object. Due to its ability to generate 3-dimensional data with high spatial resolution and accuracy, lidar technology is being increasingly used in ecology, geography, geology, geomorphology, seismology, remote sensing, and atmospheric physics. In this study we construct a 3-dimentional (3D) radiative transfer model (RTM) using lidar data to simulate the spatial distribution of solar radiation (direct and diffuse) on the surface of water and mountain forests. The model includes three sub-models: a light model simulating the light source, a sensor model simulating the camera, and a scene model simulating the landscape. We use ground-based and airborne lidar data to characterize the 3D structure of the study area, and generate a detailed 3D scene model. The interactions between light and object are simulated using the Monte Carlo Ray Tracing (MCRT) method. A large number of rays are generated from the light source. For each individual ray, the full traveling path is traced until it is absorbed or escapes from the scene boundary. By locating the sensor at different positions and directions, we can simulate the spatial distribution of solar energy at the ground, vegetation and water surfaces. These outputs can then be incorporated into meteorological drivers for hydrologic and energy balance models to improve our understanding of hydrologic processes and ecosystem functions.
Light-induced quantitative microprinting of biomolecules
NASA Astrophysics Data System (ADS)
Strale, Pierre-Olivier; Azioune, Ammar; Bugnicourt, Ghislain; Lecomte, Yohan; Chahid, Makhlad; Studer, Vincent
2017-02-01
Printing of biomolecules on substrates has developed tremendously in the past few years. The existing methods either rely on slow serial writing processes or on parallelized photolithographic techniques where cumbersome mask alignment procedures usually impair the ability to generate multi-protein patterns. We recently developed a new technology allowing for high resolution multi protein micro-patterning. This technology named "Light-Induced Molecular Adsorption of Proteins (LIMAP)" is based on a water-soluble photo-initiator able to reverse the antifouling property of polymer brushes when exposed to UV light. We developed a wide-field pattern projection system based on a DMD coupled to a conventional microscope which permits to generate arbitrary grayscale patterns of UV light at the micron scale. Interestingly, the density of adsorbed molecules scales with the dose of UV light thus allowing the quantitative patterning of biomolecules. The very low non specific background of biomolecules outside of the UV-exposed areas allows for the sequential printing of multiple proteins without alignment procedures. Protein patterns ranging from 500 nm up to 1 mm can be performed within seconds, as well as gradients of arbitrary shapes. The range of applications of the LIMAP approach extends from the single molecule up to the multicellular scale with an exquisite control over local protein density. We show that it can be used to generate complex protein landscapes useful to study protein-protein, cell-cell and cell-matrix interactions.
What would Edison do with solid state lighting?
NASA Astrophysics Data System (ADS)
Ferguson, Ian T.; Melton, Andrew; Xu, Tianming; Jamil, Muhammad; Fenwick, Will
2010-08-01
Thomas Edison is widely regarded as the greatest inventor in history and the most prominent individual behind the invention of the electric light. His impressive characteristics as an individual that led to his amazing success as an innovator continue to be an inspiration for researchers today. This paper considers how Edison might proceed in developing solid state lighting into a technology capable of displacing incumbent light sources, including his own incandescent lamps, then reviews some of the "Edison-like" contributions made to solid state lighting by the Next Generation Lighting research program at Georgia Tech.
White LED sources for vehicle forward lighting
NASA Astrophysics Data System (ADS)
Van Derlofske, John F.; McColgan, Michele W.
2002-11-01
Considerations for the use of white light emitting diode (LED) sources to produce illumination for automotive forward lighting is presented. Due to their reliability, small size, lower consumption, and lower heat generation LEDs are a natural choice for automotive lighting systems. Currently, LEDs are being sucessfully employed in most vehicle lighting applications. In these applications the light levels, distributions, and colors needed are achievable by present LED technologies. However, for vehicle white light illumination applications LEDs are now only being considered for low light level applications, such as back-up lamps. This is due to the relatively low lumen output that has been available up to now in white LEDs. With the advent of new higher lumen packages, and with the promise of even higher light output in the near future, the use of white LEDs sources for all vehicle forward lighting applications is beginning to be considered. Through computer modeling and photometric evaluation this paper examines the possibilities of using currently available white LED technology for vehicle headlamps. It is apparent that optimal LED sources for vehicle forward lighting applications will be constructed with hereto undeveloped technology and packaging configurations. However, the intent here in exploring currently available products is to begin the discussion on the design possibilities and significant issues surrounding LEDs in order to aid in the design and development of future LED sources and systems. Considerations such as total light output, physical size, optical control, power consumption, color appearance, and the effects of white LED spectra on glare and peripheral vision are explored. Finally, conclusions of the feasibility of current LED technology being used in these applications and recommendations of technology advancements that may need to occur are made.
NASA-UVA Light Aerospace Alloy and Structures Technology Program (LA2ST)
NASA Technical Reports Server (NTRS)
Gangloff, Richard P.; Starke, Edgar A., Jr.; Kelly, Robert G.; Scully, John R.; Shiflet, Gary J.; Stoner, Glenn E.; Wert, John A.
1997-01-01
The NASA-UVA Light Aerospace Alloy and Structures Technology (LA2ST) Program was initiated in 1986 and continues with a high level of activity. Here, we report on progress achieved between July I and December 31, 1996. The objective of the LA2ST Program is to conduct interdisciplinary graduate student research on the performance of next generation, light-weight aerospace alloys, composites and thermal gradient structures in collaboration with NASA-Langley researchers. Specific technical objectives are presented for each research project. We generally aim to produce relevant data and basic understanding of material mechanical response, environmental/corrosion behavior, and microstructure; new monolithic and composite alloys; advanced processing methods; new solid and fluid mechanics analyses; measurement and modeling advances; and a pool of educated graduate students for aerospace technologies. The accomplishments presented in this report are summarized as follows. Three research areas are being actively investigated, including: (1) Mechanical and Environmental Degradation Mechanisms in Advanced Light Metals, (2) Aerospace Materials Science, and (3) Mechanics of Materials for Light Aerospace Structures.
Super long viewing distance light homogeneous emitting three-dimensional display
NASA Astrophysics Data System (ADS)
Liao, Hongen
2015-04-01
Three-dimensional (3D) display technology has continuously been attracting public attention with the progress in today's 3D television and mature display technologies. The primary characteristics of conventional glasses-free autostereoscopic displays, such as spatial resolution, image depths, and viewing angle, are often limited due to the use of optical lenses or optical gratings. We present a 3D display using MEMS-scanning-mechanism-based light homogeneous emitting (LHE) approach and demonstrate that the display can directly generate an autostereoscopic 3D image without the need for optical lenses or gratings. The generated 3D image has the advantages of non-aberration and a high-definition spatial resolution, making it the first to exhibit animated 3D images with image depth of six meters. Our LHE 3D display approach can be used to generate a natural flat-panel 3D display with super long viewing distance and alternative real-time image update.
Nuclear Technology: Making Informed Decisions.
ERIC Educational Resources Information Center
Altshuler, Kenneth
1989-01-01
Discusses a unit on nuclear technology which is taught in a physics class. Explains the unit design, implementation process, demonstrations used, and topics of discussion that include light and optics, naturally and artificially produced sources of radioactivity, nuclear equations, isotopes and half-lives, and power-generating nuclear reactors.…
An Assessment of Integrated Flywheel System Technology
NASA Technical Reports Server (NTRS)
Keckler, C. R. (Editor); Bechtel, R. T. (Editor); Groom, N. J. (Editor)
1984-01-01
The current state of the technology in flywheel storage systems and ancillary components, the technology in light of future requirements, and technology development needs to rectify these shortfalls were identified. Technology efforts conducted in Europe and in the United States were reviewed. Results of developments in composite material rotors, magnetic suspension systems, motor/generators and electronics, and system dynamics and control were presented. The technology issues for the various disciplines and technology enhancement scenarios are discussed. A summary of the workshop, and conclusions and recommendations are presented.
Holographic free-electron light source
Li, Guanhai; Clarke, Brendan P.; So, Jin-Kyu; MacDonald, Kevin F.; Zheludev, Nikolay I.
2016-01-01
Recent advances in the physics and technology of light generation via free-electron proximity and impact interactions with nanostructures (gratings, photonic crystals, nano-undulators, metamaterials and antenna arrays) have enabled the development of nanoscale-resolution techniques for such applications as mapping plasmons, studying nanoparticle structural transformations and characterizing luminescent materials (including time-resolved measurements). Here, we introduce a universal approach allowing generation of light with prescribed wavelength, direction, divergence and topological charge via point-excitation of holographic plasmonic metasurfaces. It is illustrated using medium-energy free-electron injection to generate highly-directional visible to near-infrared light beams, at selected wavelengths in prescribed azimuthal and polar directions, with brightness two orders of magnitude higher than that from an unstructured surface, and vortex beams with topological charge up to ten. Such emitters, with micron-scale dimensions and the freedom to fully control radiation parameters, offer novel applications in nano-spectroscopy, nano-chemistry and sensing. PMID:27910853
NASA-UVA light aerospace alloy and structures technology program (LA2ST)
NASA Technical Reports Server (NTRS)
Gangloff, Richard P.; Starke, Edger A., Jr.
1996-01-01
This progress report covers achievements made between January 1 and June 30, 1966 on the NASA-UVA Light Aerospace Alloy and Structures Technology (LA2ST) Program. The objective of the LA2ST Program is to conduct interdisciplinary graduate student research on the performance of next generation, light-weight aerospace alloys, composites and thermal gradient structures in collaboration with NASA-Langley researchers. Specific technical objectives are presented for each research project. . The accomplishments presented in this report are: (1) Mechanical and Environmental Degradation Mechanisms in Advanced Light Metals, (2) Aerospace Materials Science, and (3) Mechanics of Materials for Light Aerospace Structures. Collective accomplishments between January and June of 1996 include: 4 journal or proceedings publications, 1 NASA progress report, 4 presentations at national technical meetings, and 2 PhD dissertations published.
NASA Astrophysics Data System (ADS)
1980-08-01
The technologies selected for the detailed characterization were: solar technology; terrestrial photovoltaic (200 MWe); coal technologies; conventional high sulfur coal combustion with advanced fine gas desulfurization (1250 MWe), and open cycle gas turbine combined cycle plant with low Btu gasifier (1250 MWe); and nuclear technologies: conventional light water reactor (1250 MWe), liquid metal fast breeder reactor (1250 MWe), and magnetic fusion reactor (1320 MWe). A brief technical summary of each power plant design is given.
NASA Astrophysics Data System (ADS)
Xu, Tingting; Close, Dan M.; Webb, James D.; Price, Sarah L.; Ripp, Steven A.; Sayler, Gary S.
2013-05-01
Bioluminescent imaging is an emerging biomedical surveillance strategy that uses external cameras to detect in vivo light generated in small animal models of human physiology or in vitro light generated in tissue culture or tissue scaffold mimics of human anatomy. The most widely utilized of reporters is the firefly luciferase (luc) gene; however, it generates light only upon addition of a chemical substrate, thus only generating intermittent single time point data snapshots. To overcome this disadvantage, we have demonstrated substrate-independent bioluminescent imaging using an optimized bacterial bioluminescence (lux) system. The lux reporter produces bioluminescence autonomously using components found naturally within the cell, thereby allowing imaging to occur continuously and in real-time over the lifetime of the host. We have validated this technology in human cells with demonstrated chemical toxicological profiling against exotoxin exposures at signal strengths comparable to existing luc systems (~1.33 × 107 photons/second). As a proof-in-principle demonstration, we have engineered breast carcinoma cells to express bioluminescence for real-time screening of endocrine disrupting chemicals and validated detection of 17β-estradiol (EC50 = ~ 10 pM). These and other applications of this new reporter technology will be discussed as potential new pathways towards improved models of target chemical bioavailability, toxicology, efficacy, and human safety.
NASA Astrophysics Data System (ADS)
Yin, Yujian; Su, Ping; Ma, Jianshe
2018-01-01
A method to improve the radial resolution using special structured light is proposed in the field of digital holographic microscopy (DHM). A specimen is illuminated with circular symmetrical structured light that makes the spectrum have radial movement, so that high frequency components of the specimen are moved into the passband of the receiver to overcome the diffraction limit. In the DHM imaging system, Computer Generated Hologram (CGH) technology is used to generate the required structured light grating. Then the grating is loaded into a spatial light modulator (SLM) to obtain specific structured illumination. After recording the hologram, digital reconstruction, for the microstructure of a binary optical element that needs to observe radial distribution, the radial resolution of the specimen is improved experimentally compare it with the result of one-dimensional sinusoidal structured light imaging. And a method of designing structured light is presented.
NASA Technical Reports Server (NTRS)
1993-01-01
Research on food growth for long duration spacecraft has resulted in a light source for growing plants indoors known as Qbeam, a solid state light source consisting of a control unit and lamp. The light source, manufactured by Quantum Devices, Inc., is not very hot, although it generates high intensity radiation. When Ron Ignatius, an industrial partner of WCSAR, realized that terrestrial plant research lighting was not energy efficient enough for space use, he and WCSAR began to experiment with light emitting diodes. A line of LED products was developed, and QDI was formed to market the technology. An LED-based cancer treatment device is currently under development.
On-chip continuous-variable quantum entanglement
NASA Astrophysics Data System (ADS)
Masada, Genta; Furusawa, Akira
2016-09-01
Entanglement is an essential feature of quantum theory and the core of the majority of quantum information science and technologies. Quantum computing is one of the most important fruits of quantum entanglement and requires not only a bipartite entangled state but also more complicated multipartite entanglement. In previous experimental works to demonstrate various entanglement-based quantum information processing, light has been extensively used. Experiments utilizing such a complicated state need highly complex optical circuits to propagate optical beams and a high level of spatial interference between different light beams to generate quantum entanglement or to efficiently perform balanced homodyne measurement. Current experiments have been performed in conventional free-space optics with large numbers of optical components and a relatively large-sized optical setup. Therefore, they are limited in stability and scalability. Integrated photonics offer new tools and additional capabilities for manipulating light in quantum information technology. Owing to integrated waveguide circuits, it is possible to stabilize and miniaturize complex optical circuits and achieve high interference of light beams. The integrated circuits have been firstly developed for discrete-variable systems and then applied to continuous-variable systems. In this article, we review the currently developed scheme for generation and verification of continuous-variable quantum entanglement such as Einstein-Podolsky-Rosen beams using a photonic chip where waveguide circuits are integrated. This includes balanced homodyne measurement of a squeezed state of light. As a simple example, we also review an experiment for generating discrete-variable quantum entanglement using integrated waveguide circuits.
NASA Astrophysics Data System (ADS)
Suhaimi, N. Sheeda; Ohae, C.; Gavara, T.; Nakagawa, K.; Hong, F.-L.; Katsuragawa, M.
2017-08-01
We have successfully generated a new broadband coherent light source in the continuous wave (CW) regime which is an ensemble of multi-harmonic radiations (2403, 1201, 801, 600 and 480 nm) by implementing a frequency dividing technology. The system is uniquely designed that all the harmonics are generated and propagate coaxially which gives the advantage of robustly maintaining the phase coherence among the harmonics. The highlight is its huge potential for the arbitrary optical waveform synthesis in the CW regime which has not been performed yet due to the limitation of the existing light source.
NASA Astrophysics Data System (ADS)
Bolan, Jeffrey; Hall, Elise; Clifford, Chris; Thurow, Brian
The Light-Field Imaging Toolkit (LFIT) is a collection of MATLAB functions designed to facilitate the rapid processing of raw light field images captured by a plenoptic camera. An included graphical user interface streamlines the necessary post-processing steps associated with plenoptic images. The generation of perspective shifted views and computationally refocused images is supported, in both single image and animated formats. LFIT performs necessary calibration, interpolation, and structuring steps to enable future applications of this technology.
Rühe, J
2017-09-26
In photolithographic processes, the light inducing the photochemical reactions is confined to a small volume, which enables direct writing of micro- and nanoscale features onto solid surfaces without the need of a predefined photomask. The direct writing process can be used to generate topographic patterns through photopolymerization or photo-cross-linking or can be employed to use light to generate chemical patterns on the surface with high spatial control, which would make such processes attractive for bioapplications. The prospects of maskless photolithography technologies with a focus on two-photon lithography and scanning-probe-based photochemical processes based on scanning near-field optical microscopy or beam pen lithography are discussed.
Simos, Nikolaos
2017-12-22
Nikolaos Simos of Brookhavenâs Energy Sciences and Technology Department and the National Synchrotron Light Source II Project presents, âExtreme Environments of Next-Generation Energy Systems and Materials: Can They Peacefully Co-Exist?â
NASA Technical Reports Server (NTRS)
1999-01-01
TerraPoint (TM) LLC is a company that combines the technologies developed at NASA's Goddard Space Flight Center (GSFC) and the Houston Advanced Research Center (HARC) with the concept of topographic real estate imaging. TerraPoint provides its customers with digital, topographical data generated by laser technology rather than commonly used microwave (radar) and photographic technologies. This product's technology merges Goddard's and HARC's laser ranging, global positioning systems, and mapping software into a miniaturized package that can be mounted in a light aircraft.
The outlook of innovative optical-electronic technologies implementation in transportation
NASA Astrophysics Data System (ADS)
Shilina, Elena V.; Ryabichenko, Roman B.
2005-06-01
Information and telecommunication technologies (ITT) are already tool economic development of society and their role will grow. The first task is providing of information security of ITT that is necessary for it distribution in "information" society. The state policy of the leading world countries (USA, France, Japan, Great Britain and China) is focused on investment huge funds in innovative technologies development. Within the next 4-6 years the main fiber-optic transfer lines will have data transfer speed 40 Gbit/s, number of packed channels 60-200 that will provide effective data transfer speed 2,4-8 Tbit/s. Photonic-crystalline fibers will be promising base of new generation fiber-optic transfer lines. The market of information imaging devices and digital photo cameras will be grown in 3-5 times. Powerful lasers based on CO2 and Nd:YAG will be actively used in transport machinery construction when producing aluminum constructions of light rolling-stock. Light-emitting diodes (LEDs) will be base for energy saving and safety light sources used for vehicles and indoor lighting. For example, in the USA cost reducing for lighting will be 200 billion dollars. Implementation analysis of optic electronic photonic technologies (OPT) in ground and aerospace systems shows that they provide significant increasing of traffic safety, crew and passengers comfort with help of smart vehicles construction and non-contact dynamic monitoring both transport facilities (for example, wheel flanges) and condition of rail track (road surface), equipping vehicles with night vision equipment. Scientific-technical programs of JSC "RZD" propose application of OPT in new generation systems: axle-box units for coaches and freight cars monitoring when they are moved, track condition analysis, mechanical stress and permanent way irregularity detection, monitoring geometric parameters of aerial contact wire, car truck, rail and wheel pair roll surface, light signals automatic detection from locomotive, video monitoring, gyroscopes based on fiber optic.
3D Printed PEG-Based Hybrid Nanocomposites Obtained by Sol-Gel Technique.
Chiappone, Annalisa; Fantino, Erika; Roppolo, Ignazio; Lorusso, Massimo; Manfredi, Diego; Fino, Paolo; Pirri, Candido Fabrizio; Calignano, Flaviana
2016-03-02
In this work, three-dimensional (3D) structured hybrid materials were fabricated combining 3D printing technology with in situ generation of inorganic nanoparticles by sol-gel technique. Those materials, consisting of silica nanodomains covalently interconnected with organic polymers, were 3D printed in complex multilayered architectures, incorporating liquid silica precursors into a photocurable oligomer in the presence of suitable photoinitiators and exposing them to a digital light system. A post sol-gel treatment in acidic vapors allowed the in situ generation of the inorganic phase in a dedicated step. This method allows to build hybrid structures operating with a full liquid formulation without meeting the drawbacks of incorporating inorganic powders into 3D printable formulations. The influence of the generated silica nanoparticle on the printed objects was deeply investigated at macro- and nanoscale; the resulting light hybrid structures show improved mechanical properties and, thus, have a huge potential for applications in a variety of advanced technologies.
OLEDs for lighting: new approaches
NASA Astrophysics Data System (ADS)
Duggal, Anil R.; Foust, Donald F.; Nealon, William F.; Heller, Christian M.
2004-02-01
OLED technology has improved to the point where it is now possible to envision developing OLEDs as a low cost solid state light source. In order to realize this, significant advances have to be made in device efficiency, lifetime at high brightness, high throughput fabrication, and the generation of illumination quality white light. In this talk, the requirements for general lighting will be reviewed and various approaches to meeting them will be outlined. Emphasis will be placed on a new monolithic series-connected OLED design architecture that promises scalability without high fabrication cost or design complexity.
NASA Astrophysics Data System (ADS)
Kim, Yong-Hae; Han, Jun-Han; Kang, Seung-Youl; Cheon, Sanghoon; Lee, Myung-Lae; Ahn, Seong-Deok; Zyung, Taehyoung; Lee, Jeong-Ik; Moon, Jaehyun; Chu, Hye Yong
2012-09-01
We are successful to lit the organic light emitting diode (OLED) lighting panel through the magnetically coupled wireless power transmission technology. For the wireless power transmission, we used the operation frequency 932 kHz, specially designed double spiral type transmitter, small and thin receiver on the four layered printed circuit board, and schottky diodes for the full bridge rectifier. Our white OLED is a hybrid type, in which phosphorescent and fluorescent organics are used together to generate stable white color. The total efficiency of power transmission is around 72%.
NASA Astrophysics Data System (ADS)
Xu, Junfeng; Li, Weile; He, Bo; Wang, Haowei; Song, Yong; Yang, Shengyi; Ni, Guoqiang
2018-01-01
Infrared detecting and display device (IR-DDD) is a newly developed optical up-conversion device that integrates the light-emitting diode (LED) onto the infrared (IR) photo-detector, in order to convert IR light into the carriers photo-generated in detection materials and inject them into LED to emit visible light. This IR-DDD can achieve the direct up-conversion from IR ray to visible light, showing the considerable potential in night-vision application. This paper attempts a review of its working principle and current research progresses.
'Leaner' lighting's dramatic impact.
Kearney, Steve
2012-04-01
Steve Kearney, business manager for Newey & Eyre - Energy Saving 24/7, a team of 'energy experts' established early last year within one of the UK's leading distributors of electrical supplies, discusses the technologies and simple measures now available to reduce emissions and cut wastage generated by lighting in healthcare facilities, at a time when the NHS, especially, is under increasing pressure to reduce its carbon footprint.
Coutts Earns Prestigious Research Award
cellsÂtheir manufacture uses less of the expensive semiconductor material that converts light into , a technology that uses heat instead of sunlight to generate electricity, and has authored or co
Optical devices: A compilation
NASA Technical Reports Server (NTRS)
1976-01-01
Technological developments in the field of optics devices which have potential utility outside the aerospace community are described. Optical instrumentation, light generation and transmission, and laser techniques are among the topics covered. Patent information is given.
NASA Astrophysics Data System (ADS)
Guo, Zhenzhen; Ming, Xin; Wang, Gang; Hou, Baofei; Liu, Xinghang; Mei, Tao; Li, Jinhua; Wang, Jianying; Wang, Xianbao
2018-02-01
Solar steam technology is one of the simplest, most direct and effective ways to harness solar energy through water evaporation. Here, we report the development using super-hydrophilic copper sulfide (CuS) films with double-layer structures as light absorbers for solar steam generation. In the double-layer structure system, a porous mixed cellulose ester (MCE) membrane is used as a supporting layer, which enables water to get into the CuS light absorbers through a capillary action to provide continuous water during solar steam generation. The super-hydrophilic property of the double-layer system (CuS/MCE) leads to a thinner water film close to the air-water interface where the surface temperature is sufficiently high, leading to more efficient evaporation (˜80 ± 2.5%) under one sun illumination. Furthermore, the evaporation efficiencies still keep a steady value after 15 cycles of testing. The super-hydrophilic CuS film is promising for practical application in water purification and evaporation as a light absorption material.
Recent Beam Measurements and New Instrumentation at the Advanced Light Source
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sannibale, F.; Baptiste, K.; Barry, W.
2012-04-11
The Advanced Light Source (ALS) in Berkeley was the first of the soft x-ray third generation light source ever built, and since 1993 has been in continuous and successful operation serving a large community of users in the VUV and soft x-ray community. During these years the storage ring underwent through several important upgrades that allowed maintaining the performance of this veteran facility at the forefront. The ALS beam diagnostics and instrumentation have followed a similar path of innovation and upgrade and nowadays include most of the modem and last generation devices and technologies that are commercially available and usedmore » in the recently constructed third generation light sources. In this paper we will not focus on such already widely known systems, but we will concentrate our effort in the description of some measurements techniques, instrumentation and diagnostic systems specifically developed at the ALS and used during the last few years.« less
RECENT BEAM MEASUREMENTS AND NEW INSTRUMENTATION AT THE ADVANCED LIGHT SOURCE
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sannibale, Fernando; Baptiste, Kenneth; Barry, Walter
2008-05-05
The Advanced Light Source (ALS) in Berkeley was the first of the soft x-ray third generation light source ever built, and since 1993 has been in continuous and successful operation serving a large community of users in the VUV and soft x-ray community. During these years the storage ring underwent through several important upgrades that allowed maintaining the performance of this veteran facility at the forefront. The ALS beam diagnostics and instrumentation have followed a similar path of innovation and upgrade and nowadays include most of the modem and last generation devices and technologies that are commercially available and usedmore » in the recently constructed third generation light sources. In this paper we will not focus on such already widely known systems, but we will concentrate our effort in the description of some measurements techniques, instrumentation and diagnostic systems specifically developed at the ALS and used during the last few years.« less
Fly-by-light flight control system technology development plan
NASA Technical Reports Server (NTRS)
Chakravarty, A.; Berwick, J. W.; Griffith, D. M.; Marston, S. E.; Norton, R. L.
1990-01-01
The results of a four-month, phased effort to develop a Fly-by-Light Technology Development Plan are documented. The technical shortfalls for each phase were identified and a development plan to bridge the technical gap was developed. The production configuration was defined for a 757-type airplane, but it is suggested that the demonstration flight be conducted on the NASA Transport Systems Research Vehicle. The modifications required and verification and validation issues are delineated in this report. A detailed schedule for the phased introduction of fly-by-light system components has been generated. It is concluded that a fiber-optics program would contribute significantly toward developing the required state of readiness that will make a fly-by-light control system not only cost effective but reliable without mitigating the weight and high-energy radio frequency related benefits.
Light emitting diodes as a plant lighting source
NASA Technical Reports Server (NTRS)
Bula, R. J.; Tennessen, D. J.; Morrow, R. C.; Tibbitts, T. W.
1994-01-01
Electroluminescence in solid materials is defined as the generation of light by the passage of an electric current through a body of solid material under an applied electric field. A specific type of electroluminescence, first noted in 1923, involves the generation of photons when electrons are passed through a p-n junction of certain solid materials (junction of a n-type semiconductor, an electron donor, and a p-type semiconductor, an electron acceptor). The development of this light emitting semiconductor technology dates back less than 30 years. During this period of time, the LED has evolved from a rare and expensive light generating device to one of the most widely used electronic components. A number of LED characteristics are of considerable importance in selecting a light source for plant lighting in a controlled environment facility. Of particular importance is the characteristic that light is generated by an LED at a rate far greater than the corresponding thermal radiation predicted by the bulk temperature of the device as defined by Plank's radiation law. This is in sharp contrast to other light sources, such as an incandescent or high intensity discharge lamp. A plant lighting system for controlled environments must provide plants with an adequate flux of photosynthetically active radiation, plus providing photons in the spectral regions that are involved in the photomorphogenic and phototropic responses that result in normal plant growth and development. Use of light sources that emit photons over a broad spectral range generally meet these two lighting requirements. Since the LED's emit over specific spectral regions, they must be carefully selected so that the levels of photsynthetically active and photomorphogenic and phototropic radiation meet these plant requirements.
Effects of solar photovoltaic technology on the environment in China.
Qi, Liqiang; Zhang, Yajuan
2017-10-01
Among the various types of renewable energy, solar photovoltaic has elicited the most attention because of its low pollution, abundant reserve, and endless supply. Solar photovoltaic technology generates both positive and negative effects on the environment. The environmental loss of 0.00666 yuan/kWh from solar photovoltaic technology is lower than that from coal-fired power generation (0.05216 yuan/kWh). The negative effects of solar photovoltaic system production include wastewater and waste gas pollutions, the representatives of which contain fluorine, chromium with wastewater and hydrogen fluoride, and silicon tetrachloride gas. Solar panels are also a source of light pollution. Improper disposal of solar cells that have reached the end of their service life harms the environment through the stench they produce and the damage they cause to the soil. So, the positive and negative effects of green energy photovoltaic power generation technology on the environment should be considered.
The novel top-coat material for RLS trade-off reduction in EUVL
NASA Astrophysics Data System (ADS)
Onishi, Ryuji; Sakamoto, Rikimaru; Fujitani, Noriaki; Endo, Takafumi; Ho, Bang-ching
2012-03-01
For the next generation lithography (NGL), several technologies have been proposed to achieve the 22nm-node devices and beyond. Extreme ultraviolet (EUV) lithography is one of the candidates for the next generation lithography. In EUV light source development, low power is one of the critical issue because of the low throughput, and another issue is Out of Band (OoB) light existing in EUV light. OoB is concerned to be the cause of deterioration for the lithography performance. In order to avoid this critical issue, we focused on development of the resist top coat material with OoB absorption property as Out of Band Protection Layer (OBPL). We designed this material having high absorbance around 240nm wavelength and high transmittance for EUV light. And this material aimed to improve sensitivity, resolution and LWR performance.
Blue light induced free radicals from riboflavin on E. coli DNA damage.
Liang, Ji-Yuan; Yuann, Jeu-Ming P; Cheng, Chien-Wei; Jian, Hong-Lin; Lin, Chin-Chang; Chen, Liang-Yu
2013-02-05
The micronutrients in many cellular processes, riboflavin (vitamin B(2)), FMN, and FAD are photo-sensitive to UV and visible light to generate reactive oxygen species (ROS). The riboflavin photochemical treatment with UV light has been applied for the inactivation of microorganisms to serve as an effective and safe technology. Ultra-violet or high-intensity radiation is, however, considered as a highly risky practice. This study was working on the application of visible LED lights to riboflavin photochemical reactions to development an effective antimicrobial treatment. The photosensitization of bacterial genome with riboflavin was investigated in vitro and in vivo by light quality and irradiation dosage. The riboflavin photochemical treatment with blue LED light was proved to be able to inactivate E. coli by damaging nucleic acids with ROS generated. Riboflavin is capable of intercalating between the bases of bacterial DNA or RNA and absorbs lights in the visible regions. LED light illumination could be a more accessible and safe practice for riboflavin photochemical treatments to achieve hygienic requirements in vitro. Copyright © 2013 Elsevier B.V. All rights reserved.
76 FR 26318 - Agency Information Collection Activities: Proposed Collection; Comment Request
Federal Register 2010, 2011, 2012, 2013, 2014
2011-05-06
... Based Standard for Fire Protection for Light Water Reactor Electric Generating Plants, 2001 Edition... or other forms of information technology? The public may examine and have copied, for a fee, publicly...
76 FR 26319 - Agency Information Collection Activities: Proposed Collection; Comment Request
Federal Register 2010, 2011, 2012, 2013, 2014
2011-05-06
... Based Standard for Fire Protection for Light Water Reactor Electric Generating Plants, 2001 Edition... techniques or other forms of information technology? The public may examine and have copied, for a fee...
Advanced Solid State Lighting for AES Deep Space Hab Project
NASA Technical Reports Server (NTRS)
Holbert, Eirik
2015-01-01
The advanced Solid State Lighting (SSL) assemblies augmented 2nd generation modules under development for the Advanced Exploration Systems Deep Space Habitat in using color therapy to synchronize crew circadian rhythms. Current RGB LED technology does not produce sufficient brightness to adequately address general lighting in addition to color therapy. The intent is to address both through a mix of white and RGB LEDs designing for fully addressable alertness/relaxation levels as well as more dramatic circadian shifts.
Enhanced second-harmonic-generation detection of collagen by means of optical wavefront shaping
NASA Astrophysics Data System (ADS)
Thompson, Jonathan V.; Throckmorton, Graham A.; Hokr, Brett H.; Yakovlev, Vladislav V.
2016-03-01
Second-harmonic generation (SHG) has proven to be an effective method to both image and detect structural variations in fibrillar collagen. The ability to detect these differences is especially useful in studying diseases like cancer and fibrosis.1 SHG techniques have historically been limited by their ability to penetrate and image through strongly scattering tissues. Recently, optical wavefront shaping has enabled light to be focused through highly scattering media such as biological tissue.2-4 This technology also enables us to examine the dependence of second harmonic generation on the spatial phase of the pump laser. Here, we demonstrate that wavefront shaping can be used to enhance the generation of second harmonic light from collagen fibrils even when scattering is low or non-existent.
NASA Astrophysics Data System (ADS)
Bisadi, Zahra; Acerbi, Fabio; Fontana, Giorgio; Zorzi, Nicola; Piemonte, Claudio; Pucker, Georg; Pavesi, Lorenzo
2018-02-01
A small-sized photonic quantum random number generator, easy to be implemented in small electronic devices for secure data encryption and other applications, is highly demanding nowadays. Here, we propose a compact configuration with Silicon nanocrystals large area light emitting device (LED) coupled to a Silicon photomultiplier to generate random numbers. The random number generation methodology is based on the photon arrival time and is robust against the non-idealities of the detector and the source of quantum entropy. The raw data show high quality of randomness and pass all the statistical tests in national institute of standards and technology tests (NIST) suite without a post-processing algorithm. The highest bit rate is 0.5 Mbps with the efficiency of 4 bits per detected photon.
The Role of Metal Halide Perovskites in Next-Generation Lighting Devices.
Lozano, Gabriel
2018-06-28
The development of smart illumination sources represents a central challenge of the current technology. In this context, the quest for novel materials that enable efficient light generation is essential. Metal halide compounds with perovskite crystalline structure (ABX3) have gained tremendous interest in the last five years since they come as easy-to-prepare high performance semiconductors. Perovskite absorbers are driving the power-conversion-efficiencies of thin film photovoltaics to unprecedented values. Nowadays, mixed-cation mixed-halide lead perovskite solar cells reach efficiencies consistently over 20% and promise to get close to 30% in multi-junction devices when combined with silicon cells at no surcharge. Nonetheless, perovskites' fame extends further since extensive research on these novel semiconductors has also revealed their brightest side. Soon after their irruption in the photovoltaic scenario, demonstration of efficient color tunable -with high color purity- perovskite emitters has opened new avenues for light generation applications that are timely to discuss herein.
Ultrafast acousto-optic mode conversion in optically birefringent ferroelectrics
NASA Astrophysics Data System (ADS)
Lejman, Mariusz; Vaudel, Gwenaelle; Infante, Ingrid C.; Chaban, Ievgeniia; Pezeril, Thomas; Edely, Mathieu; Nataf, Guillaume F.; Guennou, Mael; Kreisel, Jens; Gusev, Vitalyi E.; Dkhil, Brahim; Ruello, Pascal
2016-08-01
The ability to generate efficient giga-terahertz coherent acoustic phonons with femtosecond laser makes acousto-optics a promising candidate for ultrafast light processing, which faces electronic device limits intrinsic to complementary metal oxide semiconductor technology. Modern acousto-optic devices, including optical mode conversion process between ordinary and extraordinary light waves (and vice versa), remain limited to the megahertz range. Here, using coherent acoustic waves generated at tens of gigahertz frequency by a femtosecond laser pulse, we reveal the mode conversion process and show its efficiency in ferroelectric materials such as BiFeO3 and LiNbO3. Further to the experimental evidence, we provide a complete theoretical support to this all-optical ultrafast mechanism mediated by acousto-optic interaction. By allowing the manipulation of light polarization with gigahertz coherent acoustic phonons, our results provide a novel route for the development of next-generation photonic-based devices and highlight new capabilities in using ferroelectrics in modern photonics.
NASA-UVA light aerospace alloy and structures technology program
NASA Technical Reports Server (NTRS)
Gangloff, Richard P.; Haviland, John K.; Herakovich, Carl T.; Pilkey, Walter D.; Pindera, Marek-Jerzy; Thornton, Earl A.; Stoner, Glenn E.; Swanson, Robert E.; Wawner, Franklin E., Jr.; Wert, John A.
1989-01-01
The report on progress achieved in accomplishing of the NASA-UVA Light Aerospace Alloy and Structures Technology Program is presented. The objective is to conduct interdisciplinary graduate student research on the performance of next generation, light weight aerospace alloys and associated thermal gradient structures in close collaboration with researchers. The efforts will produce basic understanding of material behavior, new monolithic and composite alloys, processing methods, solid and fluid mechanics analyses, measurement advances, and a pool of educated graduate students. The presented accomplishments include: research on corrosion fatigue of Al-Li-Cu alloy 2090; research on the strengthening effect of small In additions to Al-Li-Cu alloys; research on localized corrosion of Al-Li alloys; research on stress corrosion cracking of Al-Li-Cu alloys; research on fiber-matrix reaction studies (Ti-1100 and Ti-15-3 matrices containing SCS-6, SCS-9, and SCS-10 fibers); and research on methods for quantifying non-random particle distribution in materials that has led to generation of a set of computer programs that can detect and characterize clusters in particles.
Spin voltage generation through optical excitation of complementary spin populations
NASA Astrophysics Data System (ADS)
Bottegoni, Federico; Celebrano, Michele; Bollani, Monica; Biagioni, Paolo; Isella, Giovanni; Ciccacci, Franco; Finazzi, Marco
2014-08-01
By exploiting the spin degree of freedom of carriers inside electronic devices, spintronics has a huge potential for quantum computation and dissipationless interconnects. Pure spin currents in spintronic devices should be driven by a spin voltage generator, able to drive the spin distribution out of equilibrium without inducing charge currents. Ideally, such a generator should operate at room temperature, be highly integrable with existing semiconductor technology, and not interfere with other spintronic building blocks that make use of ferromagnetic materials. Here we demonstrate a device that matches these requirements by realizing the spintronic equivalent of a photovoltaic generator. Whereas a photovoltaic generator spatially separates photoexcited electrons and holes, our device exploits circularly polarized light to produce two spatially well-defined electron populations with opposite in-plane spin projections. This is achieved by modulating the phase and amplitude of the light wavefronts entering a semiconductor (germanium) with a patterned metal overlayer (platinum). The resulting light diffraction pattern features a spatially modulated chirality inside the semiconductor, which locally excites spin-polarized electrons thanks to electric dipole selection rules.
NASA Astrophysics Data System (ADS)
Venter, Petrus J.; Bogalecki, Alfons W.; du Plessis, Monuko; Goosen, Marius E.; Nell, Ilse J.; Rademeyer, P.
2011-03-01
Display technologies always seem to find a wide range of interesting applications. As devices develop towards miniaturization, niche applications for small displays may emerge. While OLEDs and LCDs dominate the market for small displays, they have some shortcomings as relatively expensive technologies. Although CMOS is certainly not the dominating semiconductor for photonics, its widespread use, favourable cost and robustness present an attractive potential if it could find application in the microdisplay environment. Advances in improving the quantum efficiency of avalanche electroluminescence and the favourable spectral characteristics of light generated through the said mechanism may afford CMOS the possibility to be used as a display technology. This work shows that it is possible to integrate a fully functional display in a completely standard CMOS technology mainly geared towards digital design while using light sources completely compatible with the process and without any post processing required.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-07-21
... aviation industry in light of the changing socioeconomic dynamics of the world's technologically advanced... impact of Next Generation Air Transportation System on various aviation workforces; and (4) identifying...
Practical system for the generation of pulsed quantum frequency combs.
Roztocki, Piotr; Kues, Michael; Reimer, Christian; Wetzel, Benjamin; Sciara, Stefania; Zhang, Yanbing; Cino, Alfonso; Little, Brent E; Chu, Sai T; Moss, David J; Morandotti, Roberto
2017-08-07
The on-chip generation of large and complex optical quantum states will enable low-cost and accessible advances for quantum technologies, such as secure communications and quantum computation. Integrated frequency combs are on-chip light sources with a broad spectrum of evenly-spaced frequency modes, commonly generated by four-wave mixing in optically-excited nonlinear micro-cavities, whose recent use for quantum state generation has provided a solution for scalable and multi-mode quantum light sources. Pulsed quantum frequency combs are of particular interest, since they allow the generation of single-frequency-mode photons, required for scaling state complexity towards, e.g., multi-photon states, and for quantum information applications. However, generation schemes for such pulsed combs have, to date, relied on micro-cavity excitation via lasers external to the sources, being neither versatile nor power-efficient, and impractical for scalable realizations of quantum technologies. Here, we introduce an actively-modulated, nested-cavity configuration that exploits the resonance pass-band characteristic of the micro-cavity to enable a mode-locked and energy-efficient excitation. We demonstrate that the scheme allows the generation of high-purity photons at large coincidence-to-accidental ratios (CAR). Furthermore, by increasing the repetition rate of the excitation field via harmonic mode-locking (i.e. driving the cavity modulation at harmonics of the fundamental repetition rate), we managed to increase the pair production rates (i.e. source efficiency), while maintaining a high CAR and photon purity. Our approach represents a significant step towards the realization of fully on-chip, stable, and versatile sources of pulsed quantum frequency combs, crucial for the development of accessible quantum technologies.
NASA Technical Reports Server (NTRS)
Gangloff, Richard P.; Starke, Edgar A., Jr.; Kelly, Robert G.; Scully, John R.; Stoner, Glenn E.; Wert, John A.
1997-01-01
Since 1986, the NASA-Langley Research Center has sponsored the NASA-UVa Light Alloy and Structures Technology (LA2ST) Program at the University of Virginia (UVa). The fundamental objective of the LA2ST program is to conduct interdisciplinary graduate student research on the performance of next generation, light-weight aerospace alloys, composites and thermal gradient structures. The LA2ST program has aimed to product relevant data and basic understanding of material mechanical response, environmental/corrosion behavior, and microstructure; new monolithic and composite alloys; advanced processing methods; measurement and modeling advances; and a pool of educated graduate students for aerospace technologies. The scope of the LA2ST Program is broad. Research areas include: (1) Mechanical and Environmental Degradation Mechanisms in Advanced Light Metals and Composites, (2) Aerospace Materials Science, (3) Mechanics of materials for Aerospace Structures, and (4) Thermal Gradient Structures. A substantial series of semi-annual progress reports issued since 1987 documents the technical objectives, experimental or analytical procedures, and detailed results of graduate student research in these topical areas.
Near-field photometry for organic light-emitting diodes
NASA Astrophysics Data System (ADS)
Li, Rui; Harikumar, Krishnan; Isphording, Alexandar; Venkataramanan, Venkat
2013-03-01
Organic Light Emitting Diode (OLED) technology is rapidly maturing to be ready for next generation of light source for general lighting. The current standard test methods for solid state lighting have evolved for semiconductor sources, with point-like emission characteristics. However, OLED devices are extended surface emitters, where spatial uniformity and angular variation of brightness and colour are important. This necessitates advanced test methods to obtain meaningful data for fundamental understanding, lighting product development and deployment. In this work, a near field imaging goniophotometer was used to characterize lighting-class white OLED devices, where luminance and colour information of the pixels on the light sources were measured at a near field distance for various angles. Analysis was performed to obtain angle dependent luminous intensity, CIE chromaticity coordinates and correlated colour temperature (CCT) in the far field. Furthermore, a complete ray set with chromaticity information was generated, so that illuminance at any distance and angle from the light source can be determined. The generated ray set is needed for optical modeling and design of OLED luminaires. Our results show that luminance non-uniformity could potentially affect the luminaire aesthetics and CCT can vary with angle by more than 2000K. This leads to the same source being perceived as warm or cool depending on the viewing angle. As OLEDs are becoming commercially available, this could be a major challenge for lighting designers. Near field measurement can provide detailed specifications and quantitative comparison between OLED products for performance improvement.
Imaging camera system of OYGBR-phosphor-based white LED lighting
NASA Astrophysics Data System (ADS)
Kobashi, Katsuya; Taguchi, Tsunemasa
2005-03-01
The near-ultraviolet (nUV) white LED approach is analogous to three-color fluorescent lamp technology, which is based on the conversion of nUV radiation to visible light via the photoluminescence process in phosphor materials. The nUV light is not included in the white light generation from nUV-based white LED devices. This technology can thus provide a higher quality of white light than the blue and YAG method. A typical device demonstrates white luminescence with Tc=3,700 K, Ra > 93, K > 40 lm/W and chromaticity (x, y) = (0.39, 0.39), respectively. The orange, yellow, green and blue OYGB) or orange, yellow, red, green and blue (OYRGB) device shows a luminescence spectrum broader than of an RGB white LED and a better color rendering index. Such superior luminous characteristics could be useful for the application of several kinds of endoscope. We have shown the excellent pictures of digestive organs in a stomach of a dog due to the strong green component and high Ra.
NASA Technical Reports Server (NTRS)
2000-01-01
American Ag-Tech International, Ltd. developed a system called Quantum Tubers through the Wisconsin Center for Space Automation and Robotics (a NASA-sponsored Commercial Space Center). Using computerization and technologies originally intended for growing plants in space, the company developed a growth chamber that accelerates plant growth and is free of plant pathogens. The chamber is used to grow minitubers, which serve as nuclear seed stock for potatoes. Using lighting technology, temperature and humidity controls, and automation technology, the minituber can be generated in one closed facility with out much labor handling. This means they can be grown year round in extreme environments. The system eliminates the need for multiple generations of seed and eliminates exposure to pathogens, disease and pests. The Quantum Tubers system can produce 10-20 million tubers throughout the year, about equal to the world's supply of this generation seed stock.
A squeezed light source operated under high vacuum
Wade, Andrew R.; Mansell, Georgia L.; Chua, Sheon S. Y.; Ward, Robert L.; Slagmolen, Bram J. J.; Shaddock, Daniel A.; McClelland, David E.
2015-01-01
Non-classical squeezed states of light are becoming increasingly important to a range of metrology and other quantum optics applications in cryptography, quantum computation and biophysics. Applications such as improving the sensitivity of advanced gravitational wave detectors and the development of space-based metrology and quantum networks will require robust deployable vacuum-compatible sources. To date non-linear photonics devices operated under high vacuum have been simple single pass systems, testing harmonic generation and the production of classically correlated photon pairs for space-based applications. Here we demonstrate the production under high-vacuum conditions of non-classical squeezed light with an observed 8.6 dB of quantum noise reduction down to 10 Hz. Demonstration of a resonant non-linear optical device, for the generation of squeezed light under vacuum, paves the way to fully exploit the advantages of in-vacuum operations, adapting this technology for deployment into new extreme environments. PMID:26657616
Beyond Extreme Ultra Violet (BEUV) Radiation from Spherically symmetrical High-Z plasmas
NASA Astrophysics Data System (ADS)
Yoshida, Kensuke; Fujioka, Shinsuke; Higashiguchi, Takeshi; Ugomori, Teruyuki; Tanaka, Nozomi; Kawasaki, Masato; Suzuki, Yuhei; Suzuki, Chihiro; Tomita, Kentaro; Hirose, Ryouichi; Eshima, Takeo; Ohashi, Hayato; Nishikino, Masaharu; Scally, Enda; Nshimura, Hiroaki; Azechi, Hiroshi; O'Sullivan, Gerard
2016-03-01
Photo-lithography is a key technology for volume manufacture of high performance and compact semiconductor devices. Smaller and more complex structures can be fabricated by using shorter wavelength light in the photolithography. One of the most critical issues in development of the next generation photo-lithography is to increase energy conversion efficiency (CE) from laser to shorter wavelength light. Experimental database of beyond extreme ultraviolet (BEUV) radiation was obtained by using spherically symmetrical high-Z plasmas generated with spherically allocated laser beams. Absolute energy and spectra of BEUV light emitted from Tb, Gd, and Mo plasmas were measured with a absolutely calibrated BEUV calorimeter and a transmission grating spectrometer. 1.0 x 1012 W/cm2 is the optimal laser intensity to produced efficient BEUV light source plasmas with Tb and Gd targets. Maximum CE is achieved at 0.8% that is two times higher than the published CEs obtained with planar targets.
A squeezed light source operated under high vacuum
NASA Astrophysics Data System (ADS)
Wade, Andrew R.; Mansell, Georgia L.; Chua, Sheon S. Y.; Ward, Robert L.; Slagmolen, Bram J. J.; Shaddock, Daniel A.; McClelland, David E.
2015-12-01
Non-classical squeezed states of light are becoming increasingly important to a range of metrology and other quantum optics applications in cryptography, quantum computation and biophysics. Applications such as improving the sensitivity of advanced gravitational wave detectors and the development of space-based metrology and quantum networks will require robust deployable vacuum-compatible sources. To date non-linear photonics devices operated under high vacuum have been simple single pass systems, testing harmonic generation and the production of classically correlated photon pairs for space-based applications. Here we demonstrate the production under high-vacuum conditions of non-classical squeezed light with an observed 8.6 dB of quantum noise reduction down to 10 Hz. Demonstration of a resonant non-linear optical device, for the generation of squeezed light under vacuum, paves the way to fully exploit the advantages of in-vacuum operations, adapting this technology for deployment into new extreme environments.
NASA Astrophysics Data System (ADS)
Liu, Jie; Lewis, Larry N.; Duggal, Anil R.
2007-06-01
Organic light-emitting devices (OLEDs) usually employ at least one organic semiconductor layer that acts as a hole-injection material. The prototypical example is a conjugated polymer such as poly(3,4-ethylenedioxythiophene) heavily p doped with polystyrene sulfonic acid. Here, the authors describe a chemical doping strategy for hole injection material formulation that enables spatial patterning of the material conductivity through optical activation. The strategy utilizes an organic photoacid generator (PAG) dispersed in a polymeric organic semiconductor host. Upon UV irradiation, the PAG decomposes and generates a strong protonic acid that subsequently p dopes the host. The authors demonstrate an OLED made with such a light-activated hole-injection material and show that arbitrary emission patterning can be accomplished. This approach may provide a simple, low cost path toward specialty lighting and signage applications for OLED technology.
Self-Biased Hybrid Piezoelectric-Photoelectrochemical Cell with Photocatalytic Functionalities.
Tan, Chuan Fu; Ong, Wei Li; Ho, Ghim Wei
2015-07-28
Utilizing solar energy for environmental and energy remediations based on photocatalytic hydrogen (H2) generation and water cleaning poses great challenges due to inadequate visible-light power conversion, high recombination rate, and intermittent availability of solar energy. Here, we report an energy-harvesting technology that utilizes multiple energy sources for development of sustainable operation of dual photocatalytic reactions. The fabricated hybrid cell combines energy harvesting from light and vibration to run a power-free photocatalytic process that exploits novel metal-semiconductor branched heterostructure (BHS) of its visible light absorption, high charge-separation efficiency, and piezoelectric properties to overcome the aforementioned challenges. The desirable characteristics of conductive flexible piezoelectrode in conjunction with pronounced light scattering of hierarchical structure originate intrinsically from the elaborate design yet facile synthesis of BHS. This self-powered photocatalysis system could potentially be used as H2 generator and water treatment system to produce clean energy and water resources.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lincoln, Don
Particle accelerators can fire beams of subatomic particles at near the speed of light. The accelerating force is generated using radio frequency technology and a whole lot of interesting features. In this video, Fermilab’s Dr. Don Lincoln explains how it all works.
Unusual strategies for using indium gallium nitride grown on silicon (111) for solid-state lighting
Kim, Hoon-sik; Brueckner, Eric; Song, Jizhou; Li, Yuhang; Kim, Seok; Lu, Chaofeng; Sulkin, Joshua; Choquette, Kent; Huang, Yonggang; Nuzzo, Ralph G.; Rogers, John A.
2011-01-01
Properties that can now be achieved with advanced, blue indium gallium nitride light emitting diodes (LEDs) lead to their potential as replacements for existing infrastructure in general illumination, with important implications for efficient use of energy. Further advances in this technology will benefit from reexamination of the modes for incorporating this materials technology into lighting modules that manage light conversion, extraction, and distribution, in ways that minimize adverse thermal effects associated with operation, with packages that exploit the unique aspects of these light sources. We present here ideas in anisotropic etching, microscale device assembly/integration, and module configuration that address these challenges in unconventional ways. Various device demonstrations provide examples of the capabilities, including thin, flexible lighting “tapes” based on patterned phosphors and large collections of small light emitters on plastic substrates. Quantitative modeling and experimental evaluation of heat flow in such structures illustrates one particular, important aspect of their operation: small, distributed LEDs can be passively cooled simply by direct thermal transport through thin-film metallization used for electrical interconnect, providing an enhanced and scalable means to integrate these devices in modules for white light generation. PMID:21666096
Thermal Analysis of LED Phosphor Layer
NASA Astrophysics Data System (ADS)
Perera, Ukwatte Lokuliyanage Indika Upendra
Solid-state lighting technology has progressed to a level where light-emitting diode (LED) products are either on par or better than their traditional lighting technology counterparts with respect to efficacy and lifetime. At present, the most common method to create "white" light from LEDs for illumination applications is by using the LED primary radiation and wavelength-converting materials. In this method, the re-emission from the wavelength-converting materials excited by the LED primary radiation is combined with the LED primary radiation to create the "white" light. During this conversion process, heat is generated as a result of conversion inefficiencies and other loss mechanisms in the LED and the wavelength-converting materials. This generated heat, if not properly dissipated, increases the operating temperature, thereby increasing the light output degradation of the system over both the short and long term. The heat generation of the LED and thermal management of the LED have been studied extensively. Methods to effectively dissipate heat from the LEDs and maintain lower LED operating temperature are well understood. However, investigation of factors driving heat generation, the resulting temperature distribution in the phosphor layer, and the influence of the phosphor layer temperature on LED performance and reliability have not received the same focus. The goal of this dissertation was to understand the main factors driving heat and light generation and the transport of light and heat in the wavelength-converting layer of an LED system. Another goal was to understand the interaction between heat and light in the system and to develop and analyze a solution to reduce the wavelength-converting layer operating temperature, thereby improving light output and reliability. Even though past studies have explored generation and transfer separately for light and heat, to the best of the author's knowledge, this is the first study that has analyzed both factors simultaneously to optimize the performance of a phosphor-converted LED system, thus contributing new knowledge to the field. In this dissertation, a theoretical model was developed that modeled both light propagation and heat transfer in the wavelength-converting layer for identifying the factors influencing heat generation. This theoretical model included temperature-dependent phosphor efficiency and light absorption in the phosphor layer geometry. Experimental studies were used to validate the developed model. The model indicated good agreement with the experimental results. The developed theoretical model was then used to model experimental studies. These experiment results were compared with the model predicted results for total radiant power output of LED systems and phosphor layer surface temperature. These comparisons illustrated the effectiveness of a dedicated heat dissipation method in reducing the operating temperature of the wavelength-converting layer, and the contribution of different heat dissipation mechanisms were quantified using the developed numerical model. In addition to these short-term studies, an experiment was conducted to validate the effectiveness of the dedicated wavelength-converting heat sink design to improve system lifetime by reducing phosphor layer operating temperature. The proposed heat sink design decreased the operating temperature of the phosphor layer by ~10°C, improving lifetime by twofold. Finally, this dissertation investigated the potential of the developed theoretical model being used as a tool for prioritizing research tasks and as a design tool during the material selection and system configuration phases.
NASA Astrophysics Data System (ADS)
Rissanen, Anna; Guo, Bin; Saari, Heikki; Näsilä, Antti; Mannila, Rami; Akujärvi, Altti; Ojanen, Harri
2017-02-01
VTT's Fabry-Perot interferometers (FPI) technology enables creation of small and cost-efficient microspectrometers and hyperspectral imagers - these robust and light-weight sensors are currently finding their way into a variety of novel applications, including emerging medical products, automotive sensors, space instruments and mobile sensing devices. This presentation gives an overview of our core FPI technologies with current advances in generation of novel sensing applications including recent mobile technology demonstrators of a hyperspectral iPhone and a mobile phone CO2 sensor, which aim to advance mobile spectroscopic sensing.
Newly patented process enables low-cost solution for increasing white light spectrum of LEDs
NASA Astrophysics Data System (ADS)
Spanard, Jan-Marie
2017-10-01
A newly patented process for completing the spectral light array emitted by LED bulbs provides a low-cost method for producing better human centered lighting (HCL). This process uses non-luminescent colorant filters, filling out the jagged LED spectral emission into a full, white light array. While LED bulbs have the distinct economic advantages of using less energy, producing less heat and lasting years longer than traditional incandescent bulbs, the persistent metameric failure of LED bulbs has resulted in slower, and sometimes reluctant, adoption of LED lighting by the residential, retail and architectural markets. Adding missing wavelengths to LED generated bulbs via colorant filters increases the aesthetic appeal of the light by decreasing current levels of metameric failure, reducing the `flatness', `harshness', and `dullness' of LED generated light reported by consumers. LED phosphor-converted light can be successfully tuned to "whiter" white light with selective color filtering using permanent, durable transparent pigments. These transparent pigments are selectively applied in combination with existing manufacturing technologies and utilized as a final color-tuning step in bulb design. The quantity of emitted light chosen for color filtering can be adjusted from 1% to 100% of emitted light, creating a custom balance of light quantity with light quality. This invention recognizes that "better light" is frequently chosen over "more light" in the consumer marketplace.
Optical parametric amplification of arbitrarily polarized light in periodically poled LiNbO3.
Shao, Guang-hao; Song, Xiao-shi; Xu, Fei; Lu, Yan-qing
2012-08-13
Optical parametric amplification (OPA) of arbitrarily polarized light is proposed in a multi-section periodically poled Lithium Niobate (PPLN). External electric field is applied on selected sections to induce the polarization rotation of involved lights, thus the quasi-phase matched optical parametric processes exhibit polarization insensitivity under suitable voltage. In addition to the amplified signal wave, an idler wave with the same polarization is generated simultaneously. As an example, a ~10 times OPA showing polarization independency is simulated. Applications of this technology are also discussed.
NASA-UVA light aerospace alloy and structures technology program (LA2ST)
NASA Technical Reports Server (NTRS)
Starke, Edgar A., Jr.; Gangloff, Richard P.; Herakovich, Carl T.; Scully, John R.; Shiflet, Gary J.; Stoner, Glenn E.; Wert, John A.
1995-01-01
The NASA-UVa Light Aerospace Alloy and Structures Technology (LA2ST) Program was initiated in 1986 and continues with a high level of activity. Projects are being conducted by graduate students and faculty advisors in the Department of Materials Science and Engineering, as well as in the Department of Civil Engineering and Applied Mechanics, at the University of Virginia. Here, we report on progress achieved between July 1 and December 31, 1994. The objective of the LA2ST Program is to conduct interdisciplinary graduate student research on the performance of next generation, light-weight aerospace alloys, composites and thermal gradient structures in collaboration with NASA-Langley researchers. Specific technical objectives are presented for each research project. We generally aim to produce relevant data and basic understanding of material mechanical response, environmental/corrosion behavior, and microstructure; new monolithic and composite alloys; advanced processing methods; new solid and fluid mechanics analyses; measurement and modeling advances; and a pool of educated graduate students for aerospace technologies.
NASA-UVA Light Aerospace Alloy and Structures Technology Program: LA(2)ST
NASA Technical Reports Server (NTRS)
Gangloff, Richard P.; Haviland, John K.; Herakovich, Carl T.; Pilkey, Walter D.; Pindera, Marek-Jerzy; Scully, John R.; Stoner, Glenn E.; Thornton, Earl A.; Wawner, Franklin E., Jr.; Wert, John A.
1993-01-01
The NASA-UVA Light Aerospace Alloy and Structures Technology (LA(2)ST) Program continues a high level of activity, with projects being conducted by graduate students and faculty advisors in the Departments of Materials Science and Engineering, Civil Engineering and Applied Mechanics, and Mechanical and Aerospace Engineering at the University of Virginia. This work is funded by the NASA-Langley Research Center under Grant NAG-1-745. We report on progress achieved between July 1 and December 31, 1992. The objective of the LA(2)ST Program is to conduct interdisciplinary graduate student research on the performance of next generation, light weight aerospace alloys, composites and thermal gradient structures in collaboration with NASA-Langley researchers. Specific technical objectives are presented for each research project. We generally aim to produce relevant data and basic understanding of material mechanical response, corrosion behavior, and microstructure; new monolithic and composite alloys; advanced processing methods; new solid and fluid mechanics analyses; measurement advances; and critically, a pool of educated graduate students for aerospace technologies.
Silicate phosphors and white LED technology: improvements and opportunities
NASA Astrophysics Data System (ADS)
Sommer, Christian; Wenzl, Franz P.; Hartmann, Paul; Pachler, Peter; Schweighart, Marko; Leising, Guenther; Tasch, Stefan
2007-09-01
With the advent of a new generation of high brightness LEDs especially in the blue spectral range, white light technology based on phosphor conversion gains maturity for a successful penetration of, e.g., the general lighting market within the next years. Major challenges ahead are originating from the specific demands of the markets on small emission areas, highest possible intensities, long-term color stability, and spatial homogeneity of color coordinates. The LED industry more or less relies on the conversion phosphor classes of YAG, Sulfates, and Silicates, embedded in silicone matrices. A number of conformal coating technologies are in use. The optimization of the coating geometries with the help of software simulation offers a high potential for increased angular color homogeneity and high package densities, especially when secondary optics is in use. We report on recent progress in simulating parameters for improved white LEDs manufactured by coating technologies.
Innovative High-Performance Deposition Technology for Low-Cost Manufacturing of OLED Lighting
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hamer, John; Scott, David
In this project, OLEDWorks developed and demonstrated the innovative high-performance deposition technology required to deliver dramatic reductions in the cost of manufacturing OLED lighting in production equipment. The current high manufacturing cost of OLED lighting is the most urgent barrier to its market acceptance. The new deposition technology delivers solutions to the two largest parts of the manufacturing cost problem – the expense per area of good product for organic materials and for the capital cost and depreciation of the equipment. Organic materials cost is the largest expense item in the bill of materials and is predicted to remain somore » through 2020. The high-performance deposition technology developed in this project, also known as the next generation source (NGS), increases material usage efficiency from 25% found in current Gen2 deposition technology to 60%. This improvement alone results in a reduction of approximately 25 USD/m 2 of good product in organic materials costs, independent of production volumes. Additionally, this innovative deposition technology reduces the total depreciation cost from the estimated value of approximately 780 USD/m 2 of good product for state-of-the-art G2 lines (at capacity, 5-year straight line depreciation) to 170 USD/m 2 of good product from the OLEDWorks production line.« less
Holographic and light-field imaging for augmented reality
NASA Astrophysics Data System (ADS)
Lee, Byoungho; Hong, Jong-Young; Jang, Changwon; Jeong, Jinsoo; Lee, Chang-Kun
2017-02-01
We discuss on the recent state of the augmented reality (AR) display technology. In order to realize AR, various seethrough three-dimensional (3D) display techniques have been reported. We describe the AR display with 3D functionality such as light-field display and holography. See-through light-field display can be categorized by the optical elements which are used for see-through property: optical elements controlling path of the light-fields and those generating see-through light-field. Holographic display can be also a good candidate for AR display because it can reconstruct wavefront information and provide realistic virtual information. We introduce the see-through holographic display using various optical techniques.
Wireless sensor and actuator networks for lighting energy efficiency and user satisfaction
NASA Astrophysics Data System (ADS)
Wen, Yao-Jung
Buildings consume more than one third of the primary energy generated in the U.S., and lighting alone accounts for approximately 30% of the energy usage in commercial buildings. As the largest electricity consumer of all building electrical systems, lighting harbors the greatest potential for energy savings in the commercial sector. Fifty percent of current energy consumption could be reduced with energy-efficient lighting management strategies. While commercial products do exist, they are poorly received due to exorbitant retrofitting cost and unsatisfactory performance. As a result, most commercial buildings, especially legacy buildings, have not taken advantage of the opportunity to generate savings from lighting. The emergence of wireless sensor and actuator network (WSAN) technologies presents an alternative that circumvents costly rewiring and promises better performance than existing commercial lighting systems. The goal of this dissertation research is to develop a framework for wireless-networked lighting systems with increased cost effectiveness, energy efficiency, and user satisfaction. This research is realized through both theoretical developments and implementations. The theoretical research aims at developing techniques for harnessing WSAN technologies to lighting hardware and control strategies. Leveraging redundancy, a sensor validation and fusion algorithm is developed for extracting pertinent lighting information from the disturbance-prone desktop-mounted photosensors. An adaptive sensing strategy optimizes the timing of data acquisition and power-hungry wireless transmission of sensory feedback in real-time lighting control. Exploiting the individual addressability of wireless-enabled luminaires, a lighting optimization algorithm is developed to create the optimal lighting that minimizes energy usage while satisfying occupants' diverse lighting preferences. The wireless-networked lighting system was implemented and tested in a number of real-life settings. A human subject study conducted in a private office concluded that the research system was competitive with the commercial lighting system with much fewer retrofitting requirements. The system implemented in a shared-space office realized a self-configuring mesh network with wireless photosensors and light actuators, and demonstrated a 50% energy savings and increased performance when harvesting daylight through windows is possible. The cost analysis revealed a reasonable payback period after the system is optimized for commercialization and confirms the marketing feasibility.
Superstructures of chiral nematic microspheres as all-optical switchable distributors of light
Aβhoff, Sarah J.; Sukas, Sertan; Yamaguchi, Tadatsugu; Hommersom, Catharina A.; Le Gac, Séverine; Katsonis, Nathalie
2015-01-01
Light technology is based on generating, detecting and controlling the wavelength, polarization and direction of light. Emerging applications range from electronics and telecommunication to health, defence and security. In particular, data transmission and communication technologies are currently asking for increasingly complex and fast devices, and therefore there is a growing interest in materials that can be used to transmit light and also to control the distribution of light in space and time. Here, we design chiral nematic microspheres whose shape enables them to reflect light of different wavelengths and handedness in all directions. Assembled in organized hexagonal superstructures, these microspheres of well-defined sizes communicate optically with high selectivity for the colour and chirality of light. Importantly, when the microspheres are doped with photo-responsive molecular switches, their chiroptical communication can be tuned, both gradually in wavelength and reversibly in polarization. Since the kinetics of the “on” and “off” switching can be adjusted by molecular engineering of the dopants and because the photonic cross-communication is selective with respect to the chirality of the incoming light, these photo-responsive microspheres show potential for chiroptical all-optical distributors and switches, in which wavelength, chirality and direction of the reflected light can be controlled independently and reversibly. PMID:26400584
Luminaires for Advanced Lighting in Education
DOE Office of Scientific and Technical Information (OSTI.GOV)
Davis, J. Lynn
Evolving education methods and greater use of technology in the classroom are dictating the need to rethink facility designs, including classroom lighting. Advances in LED-based lighting technology have created the possibility of lighting systems that are not only cost effective and energy efficient, but also color-tunable and as durable as other facility infrastructures (a 20-30 year life expectancy). Thus, there is the opportunity that the modern lighting system can be used by educators as a tool in their teaching strategy. To meet this need, RTI International and Finelite, Inc. teamed to develop and test the Next Generation Integrated Classroom Lightingmore » System (NICLS). The NICLS technology incorporates a high performance, color-tunable light engine into new luminaire designs (e.g., pendant, direct-indirect, downlight, troffers) that are acceptable for use in classrooms. During this project, we successfully demonstrated that the NICLS technology achieves exceptional performance and exceeds all DOE goals for the classroom of the future, including: Luminous efficacy value for NICLS luminaires in excess of 125 lpw at all CCT values; TWL range of 2,700 K to 6,500 K while maintaining a CRI of 82 or higher at all values; Capability for full-range dimming (100% to 1%) at all CCT values with flicker levels below industry guidelines; Performance of the lighting system in a classroom mock-up, incorporating daylight and occupancy sensing to provide automatic control of lighting zones to further reduce energy consumption; Rated lifetime on the system exceeding 50,000 hours with a lumen maintenance of at least 85% at 50,000 hours; and Teacher-focused UI located at the front of the classroom to operate the lighting system. A smartphone-based UI is also available to accommodate teacher movement in the classroom. A critical element of developing this technology is designing the user interface to be compatible with modern teaching methods, including increased use of icons and colors and intuitive appearance. The design of the NICLS technology and the user interface was modified with assistance from focus groups consisting of more than 80 teachers and educational professionals total. The focus groups were held in a full-sized classroom that served as a technology demonstration site for the NICLS. The NICLS technology is an advanced lighting system for educational settings that meets or exceeds all DOE photometric, electrical, and reliability goals for the COF. The NICLS technology has been demonstrated at the classroom level, and the feedback from the dozens of teachers and educational professionals who visited the demonstration site has been overwhelmingly positive. NICLS provides a state-of-the-art lighting environment that adjusts the lighting conditions—both color and illuminance levels—to the needs of students and teachers for the task at hand. Early research has suggested that such lighting conditions will improve not only teacher effectiveness but also a student’s ability to concentrate on learning activities.« less
Sub-cycle light transients for attosecond, X-ray, four-dimensional imaging
NASA Astrophysics Data System (ADS)
Fattahi, Hanieh
2016-10-01
This paper reviews the revolutionary development of ultra-short, multi-TW laser pulse generation made possible by current laser technology. The design of the unified laser architecture discussed in this paper, based on the synthesis of ultrabroadband optical parametric chirped-pulse amplifiers, promises to provide powerful light transients with electromagnetic forces engineerable on the electron time scale. By coherent combination of multiple amplifiers operating in different wavelength ranges, pulses with wavelength spectra extending from less than 1 ?m to more than 10 ?m, with sub-cycle duration at unprecedented peak and average power levels can be generated. It is shown theoretically that these light transients enable the efficient generation of attosecond X-ray pulses with photon flux sufficient to image, for the first time, picometre-attosecond trajectories of electrons, by means of X-ray diffraction and record the electron dynamics by attosecond spectroscopy. The proposed system leads to a tool with sub-atomic spatio-temporal resolution for studying different processes deep inside matter.
Ultrafast acousto-optic mode conversion in optically birefringent ferroelectrics
Lejman, Mariusz; Vaudel, Gwenaelle; Infante, Ingrid C.; Chaban, Ievgeniia; Pezeril, Thomas; Edely, Mathieu; Nataf, Guillaume F.; Guennou, Mael; Kreisel, Jens; Gusev, Vitalyi E.; Dkhil, Brahim; Ruello, Pascal
2016-01-01
The ability to generate efficient giga–terahertz coherent acoustic phonons with femtosecond laser makes acousto-optics a promising candidate for ultrafast light processing, which faces electronic device limits intrinsic to complementary metal oxide semiconductor technology. Modern acousto-optic devices, including optical mode conversion process between ordinary and extraordinary light waves (and vice versa), remain limited to the megahertz range. Here, using coherent acoustic waves generated at tens of gigahertz frequency by a femtosecond laser pulse, we reveal the mode conversion process and show its efficiency in ferroelectric materials such as BiFeO3 and LiNbO3. Further to the experimental evidence, we provide a complete theoretical support to this all-optical ultrafast mechanism mediated by acousto-optic interaction. By allowing the manipulation of light polarization with gigahertz coherent acoustic phonons, our results provide a novel route for the development of next-generation photonic-based devices and highlight new capabilities in using ferroelectrics in modern photonics. PMID:27492493
Salar-García, M J; Gajda, I; Ortiz-Martínez, V M; Greenman, J; Hanczyc, M M; de los Ríos, A P; Ieropoulos, I A
2016-06-01
In this work, the by-product generated during the operation of cylindrical MFCs, made out of terracotta material, is investigated as a feasible means of degrading live microalgae for the first time. In addition to the low cost materials of this design, the reuse of the solution produced in the cathode renders the technology truly green and capable of generating bioenergy. In this study, the effect of a light/dark cycle or dark conditions only on the digestion of live microalgae with the catholyte is investigated. The results show that a combination of light/dark improves degradation and allows algae to be used as substrate in the anode. The addition of 12.5mL of a 1:1 mix of catholyte and microalgae (pre-digested over 5days under light/dark) to the anode, increases the power generation from 7μW to 44μW once all the organic matter in the anode had been depleted. Copyright © 2016 Elsevier Ltd. All rights reserved.
Use of light emitting diodes (LEDs) for enhanced lipid production in micro-algae based biofuels.
Severes, Alifha; Hegde, Shashank; D'Souza, L; Hegde, Smitha
2017-05-01
Microalgae are an alternative source for renewable energy to overcome the energy crises caused by exhaustion of fuel reserves. Algal biofuel technology demands a cost effective strategy for net profitable productivity. Inconsistent illumination intensities hinder microalgal growth. The light-utilizing efficiency of the cells is critical. Light scarcity leads to low production and high intensities cause photo-inhibition. We report effective usage of LEDs of different band wavelengths on the growth of microalgae in a closed, controlled environment to generate biomass and lipid yields. Among the different intensity and wavelengths tested. The light intensities of 500lx of blue-red combination gave maximum biomass in terms of cell density. LED of red light 220lx wavelength doubled the lipid dry weight from 30% (w/w) in white light to 60% (w/w). Thin layer lipid chromatogram demonstrated a dense and prominent spot of triacylglycerols in the red light, 220lx grown cultures. The FTIR profile indicates that different wavelength exposure did not alter the functional groups or change the chemical composition of the extracted lipids ensuring the quality of the product. We reiterate the fact that combination of red and blue LEDs is favoured over white light illumination for generation of biomass. In addition, we report an exciting finding of exposure to LEDs of red wavelength post-biomass generation lead to enhanced lipid production. This simple process doubled the lipid content harvested in 20days culture period. Copyright © 2017 Elsevier B.V. All rights reserved.
FY2010 Annual Progress Report for Propulsion Materials
DOE Office of Scientific and Technical Information (OSTI.GOV)
Davis, Patrick B.; Schutte, Carol L.; Gibbs, Jerry L.
The Propulsion Materials Technology actively supports the energy security and reduction of greenhouse emissions goals of the Vehicle Technologies Program by developing advanced materials that enable development of higher efficiency powertrains for ground transportation. Propulsion Materials works closely with the other disciplines within the VT Program to identify the materials properties essential for the development of cost-effective, highly efficient, and environmentally friendly next-generation heavy and light duty powertrains.
Biological photovoltaics: intra- and extra-cellular electron transport by cyanobacteria.
Bradley, Robert W; Bombelli, Paolo; Rowden, Stephen J L; Howe, Christopher J
2012-12-01
A large variety of new energy-generating technologies are being developed in an effort to reduce global dependence on fossil fuels, and to reduce the carbon footprint of energy generation. The term 'biological photovoltaic system' encompasses a broad range of technologies which all employ biological material that can harness light energy to split water, and then transfer the resulting electrons to an anode for power generation or electrosynthesis. The use of whole cyanobacterial cells is a good compromise between the requirements of the biological material to be simply organized and transfer electrons efficiently to the anode, and also to be robust and able to self-assemble and self-repair. The principle that photosynthetic bacteria can generate and transfer electrons directly or indirectly to an anode has been demonstrated by a number of groups, although the power output obtained from these devices is too low for biological photovoltaic devices to be useful outside the laboratory. Understanding how photosynthetically generated electrons are transferred through and out of the organism is key to improving power output, and investigations on this aspect of the technology are the main focus of the present review.
High Intensity Organic Light-emitting Diodes
NASA Astrophysics Data System (ADS)
Qi, Xiangfei
This thesis is dedicated to the fabrication, modeling, and characterization to achieve high efficiency organic light-emitting diodes (OLEDs) for illumination applications. Compared to conventional lighting sources, OLEDs enabled the direct conversion of electrical energy into light emission and have intrigued the world's lighting designers with the long-lasting, highly efficient illumination. We begin with a brief overview of organic technology, from basic organic semiconductor physics, to its application in optoelectronics, i.e. light-emitting diodes, photovoltaics, photodetectors and thin-film transistors. Due to the importance of phosphorescent materials, we will focus on the photophysics of metal complexes that is central to high efficiency OLED technology, followed by a transient study to examine the radiative decay dynamics in a series of phosphorescent platinum binuclear complexes. The major theme of this thesis is the design and optimization of a novel architecture where individual red, green and blue phosphorescent OLEDs are vertically stacked and electrically interconnected by the compound charge generation layers. We modeled carrier generation from the metal-oxide/doped organic interface based on a thermally assisted tunneling mechanism. The model provides insights to the optimization of a stacked OLED from both electrical and optical point of view. To realize the high intensity white lighting source, the efficient removal of heat is of a particular concern, especially in large-area devices. A fundamental transfer matrix analysis is introduced to predict the thermal properties in the devices. The analysis employs Laplace transforms to determine the response of the system to the combined effects of conduction, convection, and radiation. This perspective of constructing transmission matrices greatly facilitates the calculation of transient coupled heat transfer in a general multi-layer composite. It converts differential equations to algebraic forms, and can be expanded to study other thermal issues in more sophisticated structures.
NASA Astrophysics Data System (ADS)
Fomenkov, Igor; Brandt, David; Ershov, Alex; Schafgans, Alexander; Tao, Yezheng; Vaschenko, Georgiy; Rokitski, Slava; Kats, Michael; Vargas, Michael; Purvis, Michael; Rafac, Rob; La Fontaine, Bruno; De Dea, Silvia; LaForge, Andrew; Stewart, Jayson; Chang, Steven; Graham, Matthew; Riggs, Daniel; Taylor, Ted; Abraham, Mathew; Brown, Daniel
2017-06-01
Extreme ultraviolet (EUV) lithography is expected to succeed in 193-nm immersion multi-patterning technology for sub-10-nm critical layer patterning. In order to be successful, EUV lithography has to demonstrate that it can satisfy the industry requirements in the following critical areas: power, dose stability, etendue, spectral content, and lifetime. Currently, development of second-generation laser-produced plasma (LPP) light sources for the ASML's NXE:3300B EUV scanner is complete, and first units are installed and operational at chipmaker customers. We describe different aspects and performance characteristics of the sources, dose stability results, power scaling, and availability data for EUV sources and also report new development results.
Civil air transport: A fresh look at power-by-wire and fly-by-light
NASA Technical Reports Server (NTRS)
Sundberg, Gale R.
1990-01-01
Power-by-wire (PBW) is a key element under subsonic transport flight systems technology with potential savings of over 10 percent in gross take-off-weight and in fuel consumption compared to today's transport aircraft. The PBW technology substitutes electrical actuation in place of centralized hydraulics, uses internal starter-motor/generators and eliminates the need for variable engine bleed air to supply cabin comfort. The application of advanced fiber optics to the electrical power system controls, to built-in-test (BITE) equipment, and to fly-by-light (FBL) flight controls provides additional benefits in lightning and high energy radio frequency (HERF) immunity over existing mechanical or even fly-by-wire controls. The program plan is reviewed and a snapshot is given of the key technologies and their benefits to all future aircraft, both civil and military.
Civil air transport: A fresh look at power-by-wire and fly-by-light
NASA Technical Reports Server (NTRS)
Sundberg, Gale R.
1991-01-01
Power-by-wire (PBW) is a key element under subsonic transport flight systems technology with potential savings of over 10 percent in operating empty weight and in fuel consumption compared to today's transport aircraft. The PBW technology substitutes electrical actuation in place of centralized hydraulics, uses internal starter-motor/generators and eliminates the need for variable engine bleed air to supply cabin comfort. The application of advanced fiber optics to the electrical power system controls, to built-in-test (BIT) equipment, and to fly-by-light (FBL) flight controls provides additional benefits in lightning and high energy radio frequency (HERF) immunity over existing mechanical or even fly-by-wire controls. The program plan is reviewed and a snapshot is given of the key technologies and their benefits to all future aircraft, both civil and military.
Advantages of liquid fluoride thorium reactor in comparison with light water reactor
NASA Astrophysics Data System (ADS)
Bahri, Che Nor Aniza Che Zainul; Majid, Amran Ab.; Al-Areqi, Wadeeah M.
2015-04-01
Liquid Fluoride Thorium Reactor (LFTR) is an innovative design for the thermal breeder reactor that has important potential benefits over the traditional reactor design. LFTR is fluoride based liquid fuel, that use the thorium dissolved in salt mixture of lithium fluoride and beryllium fluoride. Therefore, LFTR technology is fundamentally different from the solid fuel technology currently in use. Although the traditional nuclear reactor technology has been proven, it has perceptual problems with safety and nuclear waste products. The aim of this paper is to discuss the potential advantages of LFTR in three aspects such as safety, fuel efficiency and nuclear waste as an alternative energy generator in the future. Comparisons between LFTR and Light Water Reactor (LWR), on general principles of fuel cycle, resource availability, radiotoxicity and nuclear weapon proliferation shall be elaborated.
Advantages of liquid fluoride thorium reactor in comparison with light water reactor
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bahri, Che Nor Aniza Che Zainul, E-mail: anizazainul@gmail.com; Majid, Amran Ab.; Al-Areqi, Wadeeah M.
2015-04-29
Liquid Fluoride Thorium Reactor (LFTR) is an innovative design for the thermal breeder reactor that has important potential benefits over the traditional reactor design. LFTR is fluoride based liquid fuel, that use the thorium dissolved in salt mixture of lithium fluoride and beryllium fluoride. Therefore, LFTR technology is fundamentally different from the solid fuel technology currently in use. Although the traditional nuclear reactor technology has been proven, it has perceptual problems with safety and nuclear waste products. The aim of this paper is to discuss the potential advantages of LFTR in three aspects such as safety, fuel efficiency and nuclearmore » waste as an alternative energy generator in the future. Comparisons between LFTR and Light Water Reactor (LWR), on general principles of fuel cycle, resource availability, radiotoxicity and nuclear weapon proliferation shall be elaborated.« less
Biosolar energy generation and harvesting from biomolecule-copolymer hybrid systems
NASA Astrophysics Data System (ADS)
Chu, Bong-Chieh Benjamin
Alternative energy sources have become an increasingly important topic as energy needs outpace supply. Furthermore, as the world moves into the digital age of portable electronics, highly efficient and lightweight energy sources will need to be developed. Current technology, such as lithium ion batteries, provide enough power to run portable electronics for hours or days, but can still allow for improvement in their power density (W/kg). Utilizing energy-transducing membrane proteins, which are by nature highly efficient, it is possible to engineer biological-based energy sources with energy densities far greater than any solid-state systems. Furthermore, solar powered membrane proteins have the added benefit of a virtually unlimited supply of energy. This work has developed protein-polymer hybrid films and nanoscale vesicles for a variety of applications from fuel-cell technology to biological-based photovoltaics. Bacteriorhodopsin (BR), a light-activated proton pump, and Cytochrome C Oxidase (COX), a protein involved in the electron transport chain in mitochondria, were reconstituted into biomimetic triblock copolymer membranes. Block copolymer membranes mimic the amphiphilic nature of a natural lipid bilayer but exhibit greater mechanical stability due to UV-polymerizable endgroups. In BR/COX functionalized nanovesicles, proton gradients generated by the light-activated proton pumping of BR are used to drive COX in reverse to generate electrons, providing a hybrid biologically-active polymer to convert solar energy to chemical energy, and finally to electrical energy. This work has found protein activity in planar membranes through the photoelectric current generation by BR and the proton pumping activity of BR-functionalized polymer membranes deposited onto proton exchange membranes, as well as the coupled functionality of BR and COX through current generation in cyclic voltammetry and direct current measurements. Current switching between light and dark environments of composite BR/COX polymer vesicles show a light-dependent current generation with current changes as high as 10muA. Furthermore, electrode modifications were made using polymer and polymer/carbon nanotube (CNT) coatings as anti-absorbent and conductive anti-absorbent layers for the purpose of a more robust electrode. These findings have shown that biological functionality can be engineered into synthetic polymers to make hybrid devices.
NASA Technical Reports Server (NTRS)
1991-01-01
Optoelectronic materials and devices are examined. Optoelectronic devices, which generate, detect, modulate, or switch electromagnetic radiation are being developed for a variety of space applications. The program includes spatial light modulators, solid state lasers, optoelectronic integrated circuits, nonlinear optical materials and devices, fiber optics, and optical networking photovoltaic technology and optical processing.
Phase singularities in 3D plasmonic crystal metamaterials for ultra-sensitive biosensing
NASA Astrophysics Data System (ADS)
Danilov, Artem; Aristov, Andrey I.; Manousidaki, Maria; Terzaki, Konstantina; Fotakis, Costas; Farsari, Maria; Kabashin, Andrei V.
2017-02-01
Plasmonic biosensors form the core label-free technology for studies of biomolecular interactions, but they still need a drastic improvement of sensitivity and novel nano-architectural implementations to match modern trends of nanobiotechnology. Here, we consider the generation of resonances in light reflected from 3D woodpile plasmonic crystal metamaterials fabricated by Direct Laser Writing by Multi-Photon Polymerization, followed by silver electroless plating. We show that the generation of these resonances is accompanied by the appearance of singularities of phase of reflected light and examine the response of phase characteristics to refractive index variations inside the metamaterial matrix. The recorded phase sensitivity (3*104 deg. of phase shift per RIU change) outperforms most plasmonic counterparts and is attributed to particular conditions of plasmon excitation in 3D plasmonic crystal geometry. Combined with a large surface for biomolecular immobilizations offered by the 3D woodpile matrix, the proposed sensor architecture promises a new important landmark in the advancement of plasmonic biosensing technology.
Kimbrow, Dustin R.; Lee, Kathryn G.
2013-01-01
Alabama Power operates a series of dams on the Coosa River in east central Alabama. These dams form six reservoirs that provide power generation, flood control, recreation, economic opportunity, and fish and wildlife habitats to the region. The Logan Martin Reservoir is located approximately 45 kilometers east of Birmingham and borders Saint Clair and Talladega Counties. Discharges below the reservoir are controlled by power generation at Logan Martin Dam, and there has been an ongoing concern about the stability of the streambanks downstream of the dam. The U.S. Geological Survey, in cooperation with Alabama Power conducted a scientific investigation of the geomorphic conditions of a 115-meter length of streambank along the Coosa River by using tripod-mounted terrestrial light detection and ranging technology. Two surveys were conducted before and after the winter flood season of 2010 to determine the extent and magnitude of geomorphic change. A comparison of the terrestrial light detection and ranging datasets indicated that approximately 40 cubic meters of material had been eroded from the upstream section of the study area. The terrestrial light detection and ranging data included in this report consist of electronic point cloud files containing several million georeferenced data points, as well as a surface model measuring changes between scans.
Development of bacterial colony phenotyping instrument using reflected scatter light
NASA Astrophysics Data System (ADS)
Doh, Iyll-Joon
Bacterial rapid detection using optical scattering technology (BARDOT) involves in differentiating elastic scattering pattern of bacterial colony. This elastic light scatter technology has shown promising label-free classification rate. However, there is limited success in certain circumstances where either a growth media or a colony has higher opacity. This situation is due to the physical principles of the current BARDOT which mainly relies on optical patterns generated by transmitted signals. Incoming light is obstructed and cannot be transmitted through the dense bacterial colonies, such as Lactobacillus, Yeast, mold and soil bacteria. Moreover, a blood agar, widely used in clinical field, is an example of an opaque media that does not allow light to be transmitted through. Therefore, in this research, a newly designed reflection type scatterometer is presented. The reflection type scatterometer measures the elastic scattering pattern generated by reflected signal. A theoretical model to study the optical pattern characteristic with respect to bacterial colony morphology is presented. Both theoretical and experiment results show good agreement that the size of backward scattering pattern has positive correlation to colony aspect ratio, a colony elevation to diameter ratio. Four pathogenic bacteria on blood agar, Escherichia coli K12, Listeria innocua, Salmonella Typhimurium, and Staphylococcus aureus, are tested and measured with proposed instrument. The measured patterns are analyzed with a classification software, and high classification rate can be achieved.
Light polarization management via reflection from arrays of sub-wavelength metallic twisted bands
NASA Astrophysics Data System (ADS)
Nawrot, M.; Haberko, J.; Zinkiewicz, Ł.; Wasylczyk, P.
2017-12-01
With constant progress of nano- and microfabrication technologies, photolithography in particular, a number of sub-wavelength metallic structures have been demonstrated that can be used to manipulate light polarization. Numerical simulations of light propagation hint that helical twisted bands can have interesting polarization properties. We use three-dimensional two-photon photolithography (direct laser writing) to fabricate a few-micrometer-thick arrays of twisted bands and coat them uniformly with metal. We demonstrate that circular polarization can be generated from linear polarization upon reflection from such structures over a broad range of frequencies in the mid infrared.
300 mW of coherent light at 488 nm using a generic approach
NASA Astrophysics Data System (ADS)
Karamehmedović, Emir; Pedersen, Christian; Andersen, Martin T.; Tidemand-Lichtenberg, Peter
2008-02-01
We present a generic approach for efficient generation of CW light with a predetermined wavelength within the visible or UV spectrum. Based on sum-frequency generation (SFG), the circulating intra-cavity field of a high-finesse diode pumped CW solid-state laser (DPSSL) and the output from a tapered, single-frequency external cavity diode laser (ECDL) are mixed inside a 10 mm periodically poled KTP crstal (pp-KTP). The pp-KTP is situated inside the DPSSL cavity to enhance conversion efficiency of the nonlinear mixing process. This approach combines different solid state technologies; the tuneability of ECDLs, the high intra-cavity filed of DPSSLs and flexible quasi phase matching in pp-tapered ECDL with a center wavelength of 766 nm in combination with a high finesse Nd:YVo4 laser at 1342 nm. Up to 308 mW of light at 488nm was measured in our experiments. The conversion of te ECDL beam was up to 47% after it was transmitted through a PM fiber, and up to 32% without fiber coupling. Replacing the seed laser and the nonlinear crystal makes it possible to generate light at virtually any desired wavelength withing the visible spectrum.
Qubit-flip-induced cavity mode squeezing in the strong dispersive regime of the quantum Rabi model
Joshi, Chaitanya; Irish, Elinor K.; Spiller, Timothy P.
2017-01-01
Squeezed states of light are a set of nonclassical states in which the quantum fluctuations of one quadrature component are reduced below the standard quantum limit. With less noise than the best stabilised laser sources, squeezed light is a key resource in the field of quantum technologies and has already improved sensing capabilities in areas ranging from gravitational wave detection to biomedical applications. In this work we propose a novel technique for generating squeezed states of a confined light field strongly coupled to a two-level system, or qubit, in the dispersive regime. Utilising the dispersive energy shift caused by the interaction, control of the qubit state produces a time-dependent change in the frequency of the light field. An appropriately timed sequence of sudden frequency changes reduces the quantum noise fluctuations in one quadrature of the field well below the standard quantum limit. The degree of squeezing and the time of generation are directly controlled by the number of frequency shifts applied. Even in the presence of realistic noise and imperfections, our protocol promises to be capable of generating a useful degree of squeezing with present experimental capabilities. PMID:28358025
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cada, Glenn
2009-12-01
This report focuses on potential impacts of marine and hydrokinetic technologies to aquatic environments (i.e. rivers, estuaries, and oceans), fish and fish habitats, ecological relationships, and other marine and freshwater aquatic resources. The report does not address impacts to terrestrial ecosystems and organisms that are common to other electricity-generating technologies (e.g., construction and maintenance of transmission lines) or possible effects on the human environment, including: human use conflicts, aesthetics, viewsheds, noise in the terrestrial environment, light, recreation, transportation, navigation, cultural resources, socioeconomic impacts.
NASA Astrophysics Data System (ADS)
Dubois, Marc; Drake, Thomas; Osterkamp, Mark; Yawn, Ken; Kaiser, David; Do, Tho; Maestas, Jeff; Thomas, Michael
2008-02-01
A laser-ultrasonic technique developed at Lockheed Martin Aeronautics called LaserUT® is used for the ultrasonic inspection of composite parts in the aeronautic industry and has demonstrated significant reduction in inspection labor and capital expenditure over approximately 20,000 parts so far. Development of new technologies will further increase LaserUT savings: structured-light mapping, improved CO2 laser, mid-infrared generation laser, and new robotic approach. Those different technologies are described and their status relatively to their introduction to production is discussed.
A gravitational wave observatory operating beyond the quantum shot-noise limit
NASA Astrophysics Data System (ADS)
Ligo Scientific Collaboration; Abadie, J.; Abbott, B. P.; Abbott, R.; Abbott, T. D.; Abernathy, M.; Adams, C.; Adhikari, R.; Affeldt, C.; Allen, B.; Allen, G. S.; Amador Ceron, E.; Amariutei, D.; Amin, R. S.; Anderson, S. B.; Anderson, W. G.; Arai, K.; Arain, M. A.; Araya, M. C.; Aston, S. M.; Atkinson, D.; Aufmuth, P.; Aulbert, C.; Aylott, B. E.; Babak, S.; Baker, P.; Ballmer, S.; Barker, D.; Barr, B.; Barriga, P.; Barsotti, L.; Barton, M. A.; Bartos, I.; Bassiri, R.; Bastarrika, M.; Batch, J.; Bauchrowitz, J.; Behnke, B.; Bell, A. S.; Belopolski, I.; Benacquista, M.; Berliner, J. M.; Bertolini, A.; Betzwieser, J.; Beveridge, N.; Beyersdorf, P. T.; Bilenko, I. A.; Billingsley, G.; Birch, J.; Biswas, R.; Black, E.; Blackburn, J. K.; Blackburn, L.; Blair, D.; Bland, B.; Bock, O.; Bodiya, T. P.; Bogan, C.; Bondarescu, R.; Bork, R.; Born, M.; Bose, S.; Brady, P. R.; Braginsky, V. B.; Brau, J. E.; Breyer, J.; Bridges, D. O.; Brinkmann, M.; Britzger, M.; Brooks, A. F.; Brown, D. A.; Brummitt, A.; Buonanno, A.; Burguet-Castell, J.; Burmeister, O.; Byer, R. L.; Cadonati, L.; Camp, J. B.; Campsie, P.; Cannizzo, J.; Cannon, K.; Cao, J.; Capano, C. D.; Caride, S.; Caudill, S.; Cavagliá, M.; Cepeda, C.; Chalermsongsak, T.; Chalkley, E.; Charlton, P.; Chelkowski, S.; Chen, Y.; Christensen, N.; Cho, H.; Chua, S. S. Y.; Chung, S.; Chung, C. T. Y.; Ciani, G.; Clara, F.; Clark, D. E.; Clark, J.; Clayton, J. H.; Conte, R.; Cook, D.; Corbitt, T. R.; Cordier, M.; Cornish, N.; Corsi, A.; Costa, C. A.; Coughlin, M.; Couvares, P.; Coward, D. M.; Coyne, D. C.; Creighton, J. D. E.; Creighton, T. D.; Cruise, A. M.; Cumming, A.; Cunningham, L.; Cutler, R. M.; Dahl, K.; Danilishin, S. L.; Dannenberg, R.; Danzmann, K.; Daudert, B.; Daveloza, H.; Davies, G.; Daw, E. J.; Dayanga, T.; Debra, D.; Degallaix, J.; Dent, T.; Dergachev, V.; Derosa, R.; Desalvo, R.; Dhurandhar, S.; Diguglielmo, J.; di Palma, I.; Díaz, M.; Donovan, F.; Dooley, K. L.; Dorsher, S.; Drever, R. W. P.; Driggers, J. C.; Du, Z.; Dumas, J.-C.; Dwyer, S.; Eberle, T.; Edgar, M.; Edwards, M.; Effler, A.; Ehrens, P.; Engel, R.; Etzel, T.; Evans, K.; Evans, M.; Evans, T.; Factourovich, M.; Fairhurst, S.; Fan, Y.; Farr, B. F.; Farr, W.; Fazi, D.; Fehrmann, H.; Feldbaum, D.; Finn, L. S.; Fisher, R. P.; Flanigan, M.; Foley, S.; Forsi, E.; Fotopoulos, N.; Frede, M.; Frei, M.; Frei, Z.; Freise, A.; Frey, R.; Fricke, T. T.; Friedrich, D.; Fritschel, P.; Frolov, V. V.; Fulda, P. J.; Fyffe, M.; Ganija, M. R.; Garcia, J.; Garofoli, J. A.; Geng, R.; Gergely, L. Á.; Gholami, I.; Ghosh, S.; Giaime, J. A.; Giampanis, S.; Giardina, K. D.; Gill, C.; Goetz, E.; Goggin, L. M.; González, G.; Gorodetsky, M. L.; Goßler, S.; Graef, C.; Grant, A.; Gras, S.; Gray, C.; Gray, N.; Greenhalgh, R. J. S.; Gretarsson, A. M.; Grosso, R.; Grote, H.; Grunewald, S.; Guido, C.; Gupta, R.; Gustafson, E. K.; Gustafson, R.; Ha, T.; Hage, B.; Hallam, J. M.; Hammer, D.; Hammond, G.; Hanks, J.; Hanna, C.; Hanson, J.; Harms, J.; Harry, G. M.; Harry, I. W.; Harstad, E. D.; Hartman, M. T.; Haughian, K.; Hayama, K.; Heefner, J.; Heintze, M. C.; Hendry, M. A.; Heng, I. S.; Heptonstall, A. W.; Herrera, V.; Hewitson, M.; Hild, S.; Hoak, D.; Hodge, K. A.; Holt, K.; Hong, T.; Hooper, S.; Hosken, D. J.; Hough, J.; Howell, E. J.; Hughey, B.; Huynh-Dinh, T.; Husa, S.; Huttner, S. H.; Ingram, D. R.; Inta, R.; Isogai, T.; Ivanov, A.; Izumi, K.; Jacobson, M.; Jang, H.; Johnson, W. W.; Jones, D. I.; Jones, G.; Jones, R.; Ju, L.; Kalmus, P.; Kalogera, V.; Kamaretsos, I.; Kandhasamy, S.; Kang, G.; Kanner, J. B.; Katsavounidis, E.; Katzman, W.; Kaufer, H.; Kawabe, K.; Kawamura, S.; Kawazoe, F.; Kells, W.; Keppel, D. G.; Keresztes, Z.; Khalaidovski, A.; Khalili, F. Y.; Khazanov, E. A.; Kim, B.; Kim, C.; Kim, D.; Kim, H.; Kim, K.; Kim, N.; Kim, Y.-M.; King, P. J.; Kinsey, M.; Kinzel, D. L.; Kissel, J. S.; Klimenko, S.; Kokeyama, K.; Kondrashov, V.; Kopparapu, R.; Koranda, S.; Korth, W. Z.; Kozak, D.; Kringel, V.; Krishnamurthy, S.; Krishnan, B.; Kuehn, G.; Kumar, R.; Kwee, P.; Lam, P. K.; Landry, M.; Lang, M.; Lantz, B.; Lastzka, N.; Lawrie, C.; Lazzarini, A.; Leaci, P.; Lee, C. H.; Lee, H. M.; Leindecker, N.; Leong, J. R.; Leonor, I.; Li, J.; Lindquist, P. E.; Lockerbie, N. A.; Lodhia, D.; Lormand, M.; Luan, J.; Lubinski, M.; Lück, H.; Lundgren, A. P.; MacDonald, E.; Machenschalk, B.; Macinnis, M.; MacLeod, D. M.; Mageswaran, M.; Mailand, K.; Mandel, I.; Mandic, V.; Marandi, A.; Márka, S.; Márka, Z.; Markosyan, A.; Maros, E.; Martin, I. W.; Martin, R. M.; Marx, J. N.; Mason, K.; Matichard, F.; Matone, L.; Matzner, R. A.; Mavalvala, N.; Mazzolo, G.; McCarthy, R.; McClelland, D. E.; McGuire, S. C.; McIntyre, G.; McIver, J.; McKechan, D. J. A.; Meadors, G. D.; Mehmet, M.; Meier, T.; Melatos, A.; Melissinos, A. C.; Mendell, G.; Menendez, D.; Mercer, R. A.; Meshkov, S.; Messenger, C.; Meyer, M. S.; Miao, H.; Miller, J.; Mitrofanov, V. P.; Mitselmakher, G.; Mittleman, R.; Miyakawa, O.; Moe, B.; Moesta, P.; Mohanty, S. D.; Moraru, D.; Moreno, G.; Mori, T.; Mossavi, K.; Mow-Lowry, C. M.; Mueller, C. L.; Mueller, G.; Mukherjee, S.; Mullavey, A.; Müller-Ebhardt, H.; Munch, J.; Murphy, D.; Murray, P. G.; Mytidis, A.; Nash, T.; Nawrodt, R.; Necula, V.; Nelson, J.; Newton, G.; Nishizawa, A.; Nolting, D.; Nuttall, L.; O'Dell, J.; O'Reilly, B.; O'Shaughnessy, R.; Ochsner, E.; Oelker, E.; Oh, J. J.; Oh, S. H.; Ogin, G. H.; Oldenburg, R. G.; Osthelder, C.; Ott, C. D.; Ottaway, D. J.; Ottens, R. S.; Overmier, H.; Owen, B. J.; Page, A.; Pan, Y.; Pankow, C.; Papa, M. A.; Ajith, P.; Patel, P.; Pedraza, M.; Peiris, P.; Pekowsky, L.; Penn, S.; Peralta, C.; Perreca, A.; Phelps, M.; Pickenpack, M.; Pinto, I. M.; Pitkin, M.; Pletsch, H. J.; Plissi, M. V.; Pöld, J.; Postiglione, F.; Predoi, V.; Price, L. R.; Prijatelj, M.; Principe, M.; Privitera, S.; Prix, R.; Prokhorov, L.; Puncken, O.; Quetschke, V.; Raab, F. J.; Radkins, H.; Raffai, P.; Rakhmanov, M.; Ramet, C. R.; Rankins, B.; Mohapatra, S. R. P.; Raymond, V.; Redwine, K.; Reed, C. M.; Reed, T.; Reid, S.; Reitze, D. H.; Riesen, R.; Riles, K.; Robertson, N. A.; Robinson, C.; Robinson, E. L.; Roddy, S.; Rodriguez, C.; Rodruck, M.; Rollins, J.; Romano, J. D.; Romie, J. H.; Röver, C.; Rowan, S.; Rüdiger, A.; Ryan, K.; Ryll, H.; Sainathan, P.; Sakosky, M.; Salemi, F.; Samblowski, A.; Sammut, L.; Sancho de La Jordana, L.; Sandberg, V.; Sankar, S.; Sannibale, V.; Santamaría, L.; Santiago-Prieto, I.; Santostasi, G.; Sathyaprakash, B. S.; Sato, S.; Saulson, P. R.; Savage, R. L.; Schilling, R.; Schlamminger, S.; Schnabel, R.; Schofield, R. M. S.; Schulz, B.; Schutz, B. F.; Schwinberg, P.; Scott, J.; Scott, S. M.; Searle, A. C.; Seifert, F.; Sellers, D.; Sengupta, A. S.; Sergeev, A.; Shaddock, D. A.; Shaltev, M.; Shapiro, B.; Shawhan, P.; Shoemaker, D. H.; Sibley, A.; Siemens, X.; Sigg, D.; Singer, A.; Singer, L.; Sintes, A. M.; Skelton, G.; Slagmolen, B. J. J.; Slutsky, J.; Smith, R. J. E.; Smith, J. R.; Smith, M. R.; Smith, N. D.; Somiya, K.; Sorazu, B.; Soto, J.; Speirits, F. C.; Stein, A. J.; Steinert, E.; Steinlechner, J.; Steinlechner, S.; Steplewski, S.; Stefszky, M.; Stochino, A.; Stone, R.; Strain, K. A.; Strigin, S.; Stroeer, A. S.; Stuver, A. L.; Summerscales, T. Z.; Sung, M.; Susmithan, S.; Sutton, P. J.; Talukder, D.; Tanner, D. B.; Tarabrin, S. P.; Taylor, J. R.; Taylor, R.; Thomas, P.; Thorne, K. A.; Thorne, K. S.; Thrane, E.; Thüring, A.; Titsler, C.; Tokmakov, K. V.; Torres, C.; Torrie, C. I.; Traylor, G.; Trias, M.; Tseng, K.; Ugolini, D.; Urbanek, K.; Vahlbruch, H.; Vallisneri, M.; van Veggel, A. A.; Vass, S.; Vaulin, R.; Vecchio, A.; Veitch, J.; Veitch, P. J.; Veltkamp, C.; Villar, A. E.; Vitale, S.; Vorvick, C.; Vyatchanin, S. P.; Wade, A.; Waldman, S. J.; Wallace, L.; Wan, Y.; Wanner, A.; Wang, X.; Wang, Z.; Ward, R. L.; Wei, P.; Weinert, M.; Weinstein, A. J.; Weiss, R.; Wen, L.; Wen, S.; Wessels, P.; West, M.; Westphal, T.; Wette, K.; Whelan, J. T.; Whitcomb, S. E.; White, D.; Whiting, B. F.; Wilkinson, C.; Willems, P. A.; Williams, H. R.; Williams, L.; Willke, B.; Winkelmann, L.; Winkler, W.; Wipf, C. C.; Wittel, H.; Wiseman, A. G.; Woan, G.; Wooley, R.; Worden, J.; Yablon, J.; Yakushin, I.; Yamamoto, K.; Yamamoto, H.; Yang, H.; Yeaton-Massey, D.; Yoshida, S.; Yu, P.; Zanolin, M.; Zhang, L.; Zhang, W.; Zhang, Z.; Zhao, C.; Zotov, N.; Zucker, M. E.; Zweizig, J.
2011-12-01
Around the globe several observatories are seeking the first direct detection of gravitational waves (GWs). These waves are predicted by Einstein's general theory of relativity and are generated, for example, by black-hole binary systems. Present GW detectors are Michelson-type kilometre-scale laser interferometers measuring the distance changes between mirrors suspended in vacuum. The sensitivity of these detectors at frequencies above several hundred hertz is limited by the vacuum (zero-point) fluctuations of the electromagnetic field. A quantum technology--the injection of squeezed light--offers a solution to this problem. Here we demonstrate the squeezed-light enhancement of GEO600, which will be the GW observatory operated by the LIGO Scientific Collaboration in its search for GWs for the next 3-4 years. GEO600 now operates with its best ever sensitivity, which proves the usefulness of quantum entanglement and the qualification of squeezed light as a key technology for future GW astronomy.
Impact of the proposed energy tax on nuclear electric generating technologies
DOE Office of Scientific and Technical Information (OSTI.GOV)
Edmunds, T.A.; Lamont, A.D.; Pasternak, A.D.
1993-05-01
The President`s new economic initiatives include an energy tax that will affect the costs of power from most electric generating technologies. The tax on nuclear power could be applied in a number of different ways at several different points in the fuel cycle. These different approaches could have different effects on the generation costs and benefits of advanced reactors. The Office of Nuclear Energy has developed models for assessing the costs and benefits of advanced reactor cycles which must be updated to take into account the impacts of the proposed tax. This report has been prepared to assess the spectrummore » of impacts of the energy tax on nuclear power and can be used in updating the Office`s economic models. This study was conducted in the following steps. First, the most authoritative statement of the proposed tax available at this time was obtained. Then the impacts of the proposed tax on the costs of nuclear and fossil fueled generation were compared. Finally several other possible approaches to taxing nuclear energy were evaluated. The cost impact on several advanced nuclear technologies and a current light water technology were computed. Finally, the rationale for the energy tax as applied to various electric generating methods was examined.« less
Virtual viewpoint generation for three-dimensional display based on the compressive light field
NASA Astrophysics Data System (ADS)
Meng, Qiao; Sang, Xinzhu; Chen, Duo; Guo, Nan; Yan, Binbin; Yu, Chongxiu; Dou, Wenhua; Xiao, Liquan
2016-10-01
Virtual view-point generation is one of the key technologies the three-dimensional (3D) display, which renders the new scene image perspective with the existing viewpoints. The three-dimensional scene information can be effectively recovered at different viewing angles to allow users to switch between different views. However, in the process of multiple viewpoints matching, when N free viewpoints are received, we need to match N viewpoints each other, namely matching C 2N = N(N-1)/2 times, and even in the process of matching different baselines errors can occur. To address the problem of great complexity of the traditional virtual view point generation process, a novel and rapid virtual view point generation algorithm is presented in this paper, and actual light field information is used rather than the geometric information. Moreover, for better making the data actual meaning, we mainly use nonnegative tensor factorization(NTF). A tensor representation is introduced for virtual multilayer displays. The light field emitted by an N-layer, M-frame display is represented by a sparse set of non-zero elements restricted to a plane within an Nth-order, rank-M tensor. The tensor representation allows for optimal decomposition of a light field into time-multiplexed, light-attenuating layers using NTF. Finally, the compressive light field of multilayer displays information synthesis is used to obtain virtual view-point by multiple multiplication. Experimental results show that the approach not only the original light field is restored with the high image quality, whose PSNR is 25.6dB, but also the deficiency of traditional matching is made up and any viewpoint can obtained from N free viewpoints.
NASA Technical Reports Server (NTRS)
1989-01-01
When Enerpro, Inc. president, Frank J. Bourbeau, attempted to file a patent on a system for synchronizing a wind generator to the electric utility grid, he discovered Marshall Space Flight Center's Frank Nola's power factor controller. Bourbeau advanced the technology and received a NASA license and a patent for his Auto Synchronous Controller (ASC). The ASC reduces generator "inrush current," which occurs when large generators are abruptly brought on line. It controls voltage so the generator is smoothly connected to the utility grid when it reaches its synchronous speed, protecting the components from inrush current damage. Generator efficiency is also increased in light winds by applying lower than rated voltage. Wind energy is utilized to drive turbines to generate electricity for utility companies.
Ultrahigh-definition dynamic 3D holographic display by active control of volume speckle fields
NASA Astrophysics Data System (ADS)
Yu, Hyeonseung; Lee, Kyeoreh; Park, Jongchan; Park, Yongkeun
2017-01-01
Holographic displays generate realistic 3D images that can be viewed without the need for any visual aids. They operate by generating carefully tailored light fields that replicate how humans see an actual environment. However, the realization of high-performance, dynamic 3D holographic displays has been hindered by the capabilities of present wavefront modulator technology. In particular, spatial light modulators have a small diffraction angle range and limited pixel number limiting the viewing angle and image size of a holographic 3D display. Here, we present an alternative method to generate dynamic 3D images by controlling volume speckle fields significantly enhancing image definition. We use this approach to demonstrate a dynamic display of micrometre-sized optical foci in a volume of 8 mm × 8 mm × 20 mm.
NASA-UVA light aerospace alloy and structures technology program (LA2ST)
NASA Technical Reports Server (NTRS)
Gangloff, Richard P.; Scully, John R.; Starke, Edgar A., Jr.; Stoner, Glenn E.; Thornton, Earl A.; Wawner, Franklin E., Jr.; Wert, John A.
1994-01-01
The NASA-UVA Light Aerospace Alloy and Structures Technology (LA2ST) Program was initiated in 1986, and continues a high level of activity, with projects being conducted by graduate students and faculty advisors in the Departments of Materials Science and Engineering, and Mechanical and Aerospace Engineering at the University of Virginia. This work is funded by the NASA-Langley Research Center under Grant NAG-1-745. Here, we report on progress achieved between July 1 and December 31, 1993. The objective of the LA2ST Program is to conduct interdisciplinary graduate student research on the performance of next generation, light weight aerospace alloys, composites and thermal gradient structures in collaboration with NASA-Langley researchers. Specific technical objectives are presented for each research project. We generally aim to produce relevant data and basic understanding of material mechanical response, environmental/corrosion behavior, and microstructure; new monolithic and composite alloys; advanced processing methods; new solid and fluid mechanics analyses; measurement and modeling advances; and critically, a pool of educated graduate students for aerospace technologies.
NASA-UVA light aerospace alloy and structures technology program (LA2ST)
NASA Astrophysics Data System (ADS)
Gangloff, Richard P.; Scully, John R.; Starke, Edgar A., Jr.; Stoner, Glenn E.; Thornton, Earl A.; Wawner, Franklin E., Jr.; Wert, John A.
1994-03-01
The NASA-UVA Light Aerospace Alloy and Structures Technology (LA2ST) Program was initiated in 1986, and continues a high level of activity, with projects being conducted by graduate students and faculty advisors in the Departments of Materials Science and Engineering, and Mechanical and Aerospace Engineering at the University of Virginia. This work is funded by the NASA-Langley Research Center under Grant NAG-1-745. Here, we report on progress achieved between July 1 and December 31, 1993. The objective of the LA2ST Program is to conduct interdisciplinary graduate student research on the performance of next generation, light weight aerospace alloys, composites and thermal gradient structures in collaboration with NASA-Langley researchers. Specific technical objectives are presented for each research project. We generally aim to produce relevant data and basic understanding of material mechanical response, environmental/corrosion behavior, and microstructure; new monolithic and composite alloys; advanced processing methods; new solid and fluid mechanics analyses; measurement and modeling advances; and critically, a pool of educated graduate students for aerospace technologies.
Photoelectrochemically driven self-assembly method
Nielson, Gregory N.; Okandan, Murat
2017-01-17
Various technologies described herein pertain to assembling electronic devices into a microsystem. The electronic devices are disposed in a solution. Light can be applied to the electronic devices in the solution. The electronic devices can generate currents responsive to the light applied to the electronic devices in the solution, and the currents can cause electrochemical reactions that functionalize regions on surfaces of the electronic devices. Additionally or alternatively, the light applied to the electronic devices in the solution can cause the electronic devices to generate electric fields, which can orient the electronic devices and/or induce movement of the electronic devices with respect to a receiving substrate. Further, electrodes on a receiving substrate can be biased to attract and form connections with the electronic devices having the functionalized regions on the surfaces. The microsystem can include the receiving substrate and the electronic devices connected to the receiving substrate.
Fully solution-processed, transparent organic power-generating polarizer
NASA Astrophysics Data System (ADS)
Chou, Wei-Yu; Hsu, Fang-Chi; Chen, Yang-Fang
2017-03-01
We fabricate transparent organic power-generating polarizer by all solution process. Based on the conventional indium-tin-oxide-coated glass as the bottom cathode, the subsequent layers are prepared by a combination of solution processing methods. Sprayed silver nanowires film serves as the top anode and can transmit greater than 80% of the visible light with sheet resistance of 16 Ω/□. By adopting the quasi-bilayer structure for the photoactive layer composed of rubbed polymer donors to produce anisotropic optical property underneath fullerene acceptors, the finished device demonstrates a power conversion efficiency of 1.36% with unpolarized light, a dichroic ratio of 3.2, and a high short circuit current ratio of 2.6 with polarized light. Our proposed fabrication procedures of devices take into account not only the cost-effective production, but also the flexibility of devices for applying in flexible, scalable circuits to advance the development of future technology.
NASA Astrophysics Data System (ADS)
Held, Marcel Philipp; Ley, Peer-Phillip; Lachmayer, Roland
2018-02-01
High-resolution vehicle headlamps represent a future-oriented technology that increases traffic safety and driving comfort in the dark. A further development to current matrix beam headlamps are LED-based pixellight systems which enable additional lighting functions (e.g. the projection of navigation information on the road) to be activated for given driving scenarios. The image generation is based on spatial light modulators (SLM) such as digital micromirror devices (DMD), liquid crystal displays (LCD), liquid crystal on silicon (LCoS) devices or LED arrays. For DMD-, LCD- and LCoSbased headlamps, the optical system uses illumining optics to ensure a precise illumination of the corresponding SLM. LED arrays, however, have to use imaging optics to project the LED die onto an intermediate image plane and thus create the light distribution via an apposition of gapless juxtapositional LED die images. Nevertheless, the lambertian radiation characteristics complex the design of imaging optics regarding a highefficiency setup with maximum resolution and luminous flux. Simplifying the light source model and its emitting characteristics allows to determine a balanced setup between these parameters by using the Etendue and to ´ calculate the maximum possible efficacy and luminous flux for each technology in an early designing stage. Therefore, we present a calculation comparison of how simplifying the light source model can affect the Etendue ´ conservation and the setup design for two high-resolution technologies. The shown approach is evaluated and compared to simulation models to show the occurring deviation and its applicability.
Visible-Infrared Hyperspectral Image Projector
NASA Technical Reports Server (NTRS)
Bolcar, Matthew
2013-01-01
The VisIR HIP generates spatially-spectrally complex scenes. The generated scenes simulate real-world targets viewed by various remote sensing instruments. The VisIR HIP consists of two subsystems: a spectral engine and a spatial engine. The spectral engine generates spectrally complex uniform illumination that spans the wavelength range between 380 nm and 1,600 nm. The spatial engine generates two-dimensional gray-scale scenes. When combined, the two engines are capable of producing two-dimensional scenes with a unique spectrum at each pixel. The VisIR HIP can be used to calibrate any spectrally sensitive remote-sensing instrument. Tests were conducted on the Wide-field Imaging Interferometer Testbed at NASA s Goddard Space Flight Center. The device is a variation of the calibrated hyperspectral image projector developed by the National Institute of Standards and Technology in Gaithersburg, MD. It uses Gooch & Housego Visible and Infrared OL490 Agile Light Sources to generate arbitrary spectra. The two light sources are coupled to a digital light processing (DLP(TradeMark)) digital mirror device (DMD) that serves as the spatial engine. Scenes are displayed on the DMD synchronously with desired spectrum. Scene/spectrum combinations are displayed in rapid succession, over time intervals that are short compared to the integration time of the system under test.
Speed breeding is a powerful tool to accelerate crop research and breeding.
Watson, Amy; Ghosh, Sreya; Williams, Matthew J; Cuddy, William S; Simmonds, James; Rey, María-Dolores; Asyraf Md Hatta, M; Hinchliffe, Alison; Steed, Andrew; Reynolds, Daniel; Adamski, Nikolai M; Breakspear, Andy; Korolev, Andrey; Rayner, Tracey; Dixon, Laura E; Riaz, Adnan; Martin, William; Ryan, Merrill; Edwards, David; Batley, Jacqueline; Raman, Harsh; Carter, Jeremy; Rogers, Christian; Domoney, Claire; Moore, Graham; Harwood, Wendy; Nicholson, Paul; Dieters, Mark J; DeLacy, Ian H; Zhou, Ji; Uauy, Cristobal; Boden, Scott A; Park, Robert F; Wulff, Brande B H; Hickey, Lee T
2018-01-01
The growing human population and a changing environment have raised significant concern for global food security, with the current improvement rate of several important crops inadequate to meet future demand 1 . This slow improvement rate is attributed partly to the long generation times of crop plants. Here, we present a method called 'speed breeding', which greatly shortens generation time and accelerates breeding and research programmes. Speed breeding can be used to achieve up to 6 generations per year for spring wheat (Triticum aestivum), durum wheat (T. durum), barley (Hordeum vulgare), chickpea (Cicer arietinum) and pea (Pisum sativum), and 4 generations for canola (Brassica napus), instead of 2-3 under normal glasshouse conditions. We demonstrate that speed breeding in fully enclosed, controlled-environment growth chambers can accelerate plant development for research purposes, including phenotyping of adult plant traits, mutant studies and transformation. The use of supplemental lighting in a glasshouse environment allows rapid generation cycling through single seed descent (SSD) and potential for adaptation to larger-scale crop improvement programs. Cost saving through light-emitting diode (LED) supplemental lighting is also outlined. We envisage great potential for integrating speed breeding with other modern crop breeding technologies, including high-throughput genotyping, genome editing and genomic selection, accelerating the rate of crop improvement.
Feasibility and technology for making remote measurements of solutes in water
Goldberg, Marvin C.; Weiner, Eugene R.
1977-01-01
An indepth evaluation of the available technology in the field of laser-Raman spectroscopy indicates that a TV-type detector, a single monochromator with a holographic grating, an entrance slit filter blocking the Rayleigh light, and a pulsed laser coupled to signal averaging electronics is the best combination of commercial equipment that is presently available for building a remote water-quality sensor. The resultant sensor would be capable of measuring oxyanions in water at concentrations from 10 to 50 milligrams per liter at distances from ground level to 30 meters above the sample. The main interferences would be ambient light, bioluminescence, and natural fluorescence, all of which are minimized when taking advantage of the signal generating and readout capability contained in this equipment package.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-05-26
... of Our Nation's Fleet of Cars And Trucks Memorandum for the Secretary of Transportation[,] the... the development of a new generation of clean cars and trucks through innovative technologies and..., 2010, which regulates these attributes of passenger cars and light-duty trucks for model years 2012...
Fast Tract to Currency through Curriculum Morphing.
ERIC Educational Resources Information Center
Guenther, A. H.; Hull, Darrell
This document addresses the challenges and opportunities technological advances are presenting in education. Using the example of Photonics (defined as the generation, manipulation, transport, detection and use of light information and energy whose quantium unit is the photon) the report illustrates the need for up-to-date educational curricula.…
Titanium dioxide (TiO2) photocatalysis has become one of the most effective advanced oxidation technologies (AOTs) for the treatment of persistent organic contaminants. To generate hydroxyl radicals, a non-selective, reactive oxidizing species and responsible for the oxidation of...
What We Talk About When We Talk About Light.
Forbes, Malcolm D E
2015-10-28
UNESCO (the United Nations Educational, Scientific, and Cultural Organization) has declared 2015 the "International Year of Light and Light-Based Technologies". In celebration of this proclamation, this Outlook provides a general history of light and its applications, from the earliest moments of the Big Bang through its present impact on all forms of life on the planet. Special emphasis is placed on fundamental advances in the generation and use of artificial light, as well as the harvesting and use of light from the Sun and other natural sources. During the past century, the role of light in the fields of physics, chemistry, and biology has expanded to include emerging fields such as environmental engineering, agriculture, materials science, and biomedicine. In this regard, future research challenges and new potential applications in these areas, in the context of "the central science", are presented and discussed.
High speed photodiodes in standard nanometer scale CMOS technology: a comparative study.
Nakhkoob, Behrooz; Ray, Sagar; Hella, Mona M
2012-05-07
This paper compares various techniques for improving the frequency response of silicon photodiodes fabricated in mainstream CMOS technology for fully integrated optical receivers. The three presented photodiodes, Spatially Modulated Light detectors, Double, and Interrupted P-Finger photodiodes, aim at reducing the low speed diffusive component of the photo generated current. For the first photodiode, Spatially Modulated Light (SML) detectors, the low speed current component is canceled out by converting it to a common mode current driving a differential transimpedance amplifier. The Double Photodiode (DP) uses two depletion regions to increase the fast drift component, while the Interrupted-P Finger Photodiode (IPFPD) redirects the low speed component towards a different contact from the main fast terminal of the photodiode. Extensive device simulations using 130 nm CMOS technology-parameters are presented to compare their performance using the same technological platform. Finally a new type of photodiode that uses triple well CMOS technology is introduced that can achieve a bandwidth of roughly 10 GHz without any process modification or high reverse bias voltages that would jeopardize the photodetector and subsequent transimpedance amplifier reliability.
NASA Technical Reports Server (NTRS)
Brady, Tye; Bailey, Erik; Crain, Timothy; Paschall, Stephen
2011-01-01
NASA has embarked on a multiyear technology development effort to develop a safe and precise lunar landing capability. The Autonomous Landing and Hazard Avoidance Technology (ALHAT) Project is investigating a range of landing hazard detection methods while developing a hazard avoidance capability to best field test the proper set of relevant autonomous GNC technologies. Ultimately, the advancement of these technologies through the ALHAT Project will provide an ALHAT System capable of enabling next generation lunar lander vehicles to globally land precisely and safely regardless of lighting condition. This paper provides an overview of the ALHAT System and describes recent validation experiments that have advanced the highly capable GNC architecture.
SEI power source alternatives for rovers and other multi-kWe distributed surface applications
NASA Technical Reports Server (NTRS)
Bents, David J.; Kohout, L. L.; Mckissock, Barbara I.; Rodriguez, C. D.; Withrow, C. A.; Colozza, A.; Hanlon, James C.; Schmitz, Paul C.
1991-01-01
To support the Space Exploration Initiative (SEI), a study was performed to investigate power system alternatives for the rover vehicles and servicers that were subsequently generated for each of these rovers and servicers, candidate power sources incorporating various power generation and energy storage technologies were identified. The technologies were those believed most appropriate to the SEI missions, and included solar, electrochemical, and isotope systems. The candidates were characterized with respect to system mass, deployed area, and volume. For each of the missions a preliminary selection was made. Results of this study depict the available power sources in light of mission requirements as they are currently defined.
NASA-UVA light aerospace alloy and structures technology program (LA2ST)
NASA Technical Reports Server (NTRS)
Gangloff, Richard P.
1992-01-01
The NASA-UVa Light Aerospace Alloy and Structure Technology (LAST) Program continues to maintain a high level of activity, with projects being conducted by graduate students and faculty advisors in the Departments of Materials Science and Engineering, Civil Engineering and Applied Mechanics, and Mechanical and Aerospace Engineering at the University of Virginia. This work is funded by the NASA-Langley Research Center under Grant NAG-1-745. Here, we report on progress achieved between January 1 and June 30, 1992. The objectives of the LA2ST Program is to conduct interdisciplinary graduate student research on the performance of the next generation, light weight aerospace alloys, composites and thermal gradient structures in collaboration with Langley researchers. Technical objectives are established for each research project. We aim to produce relevant data and basic understanding of material mechanical response, corrosion behavior, and microstructure; new monolithic and composite alloys; advanced processing methods; new solid and fluid mechanics analyses; measurement advances; and critically, a pool of educated graduate students for aerospace technologies. The accomplishments presented in this report cover topics including: (1) Mechanical and Environmental Degradation Mechanisms in Advance Light Metals and Composites; (2) Aerospace Materials Science; (3) Mechanics of Materials and Composites for Aerospace Structures; and (4) Thermal Gradient Structures.
Kinect the dots: 3D control of optical tweezers
NASA Astrophysics Data System (ADS)
Shaw, Lucy; Preece, Daryl; Rubinsztein-Dunlop, Halina
2013-07-01
Holographically generated optical traps confine micron- and sub-micron sized particles close to the center of focused light beams. They also provide a way of trapping multiple particles and moving them in three dimensions. However, in many systems the user interface is not always advantageous or intuitive especially for collaborative work and when depth information is required. We discuss and evaluate a set of multi-beam optical tweezers that utilize off the shelf gaming technology to facilitate user interaction. We use the Microsoft Kinect sensor bar as a way of getting the user input required to generate arbitrary optical force fields and control optically trapped particles. We demonstrate that the system can also be used for dynamic light control.
Semiconductor Nanocrystals as Light Harvesters in Solar Cells
Etgar, Lioz
2013-01-01
Photovoltaic cells use semiconductors to convert sunlight into electrical current and are regarded as a key technology for a sustainable energy supply. Quantum dot-based solar cells have shown great potential as next generation, high performance, low-cost photovoltaics due to the outstanding optoelectronic properties of quantum dots and their multiple exciton generation (MEG) capability. This review focuses on QDs as light harvesters in solar cells, including different structures of QD-based solar cells, such as QD heterojunction solar cells, QD-Schottky solar cells, QD-sensitized solar cells and the recent development in organic-inorganic perovskite heterojunction solar cells. Mechanisms, procedures, advantages, disadvantages and the latest results obtained in the field are described. To summarize, a future perspective is offered. PMID:28809318
LYSO-based precision timing detectors with SiPM readout
NASA Astrophysics Data System (ADS)
Bornheim, A.; Hassanshahi, M. H.; Griffioen, M.; Mao, J.; Mangu, A.; Peña, C.; Spiropulu, M.; Xie, S.; Zhang, Z.
2018-07-01
Particle detectors based on scintillation light are particularly well suited for precision timing applications with resolutions of a few 10's of ps. The large primary signal and the initial rise time of the scintillation light result in very favorable signal-to-noise conditions with fast signals. In this paper we describe timing studies using a LYSO-based sampling calorimeter with wavelength-shifting capillary light extraction and silicon photomultipliers as photosensors. We study the contributions of various steps of the signal generation to the total time resolution, and demonstrate its feasibility as a radiation-hard technology for calorimeters at high intensity hadron colliders.
Liu, Xiao-Yuan; Chen, Hao; Wang, Ruili; Shang, Yuequn; Zhang, Qiong; Li, Wei; Zhang, Guozhen; Su, Juan; Dinh, Cao Thang; de Arquer, F Pelayo García; Li, Jie; Jiang, Jun; Mi, Qixi; Si, Rui; Li, Xiaopeng; Sun, Yuhan; Long, Yi-Tao; Tian, He; Sargent, Edward H; Ning, Zhijun
2017-06-01
Hydrogen generation via photocatalysis-driven water splitting provides a convenient approach to turn solar energy into chemical fuel. The development of photocatalysis system that can effectively harvest visible light for hydrogen generation is an essential task in order to utilize this technology. Herein, a kind of cadmium free Zn-Ag-In-S (ZAIS) colloidal quantum dots (CQDs) that shows remarkably photocatalytic efficiency in the visible region is developed. More importantly, a nanocomposite based on the combination of 0D ZAIS CQDs and 2D MoS 2 nanosheet is developed. This can leverage the strong light harvesting capability of CQDs and catalytic performance of MoS 2 simultaneously. As a result, an excellent external quantum efficiency of 40.8% at 400 nm is achieved for CQD-based hydrogen generation catalyst. This work presents a new platform for the development of high-efficiency photocatalyst based on 0D-2D nanocomposite. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
De Novo Adult Transcriptomes of Two European Brittle Stars: Spotlight on Opsin-Based Photoreception
Mallefet, Jérôme; Flammang, Patrick
2016-01-01
Next generation sequencing (NGS) technology allows to obtain a deeper and more complete view of transcriptomes. For non-model or emerging model marine organisms, NGS technologies offer a great opportunity for rapid access to genetic information. In this study, paired-end Illumina HiSeqTM technology has been employed to analyse transcriptomes from the arm tissues of two European brittle star species, Amphiura filiformis and Ophiopsila aranea. About 48 million Illumina reads were generated and 136,387 total unigenes were predicted from A. filiformis arm tissues. For O. aranea arm tissues, about 47 million reads were generated and 123,324 total unigenes were obtained. Twenty-four percent of the total unigenes from A. filiformis show significant matches with sequences present in reference online databases, whereas, for O. aranea, this percentage amounts to 23%. In both species, around 50% of the predicted annotated unigenes were significantly similar to transcripts from the purple sea urchin, the closest species to date that has undergone complete genome sequencing and annotation. GO, COG and KEGG analyses were performed on predicted brittle star unigenes. We focused our analyses on the phototransduction actors involved in light perception. Firstly, two new echinoderm opsins were identified in O. aranea: one rhabdomeric opsin (homologous to vertebrate melanopsin) and one RGR opsin. The RGR-opsin is supposed to be involved in retinal regeneration while the r-opsin is suspected to play a role in visual-like behaviour. Secondly, potential phototransduction actors were identified in both transcriptomes using the fly (rhabdomeric) and mammal (ciliary) classical phototransduction pathways as references. Finally, the sensitivity of O.aranea to monochromatic light was investigated to complement data available for A. filiformis. The presence of microlens-like structures at the surface of dorsal arm plate of O. aranea could potentially explain phototactic behaviour differences between the two species. The results confirm (i) the ability of these brittle stars to perceive light using opsin-based photoreception, (ii) suggest the co-occurrence of both rhabdomeric and ciliary photoreceptors, and (iii) emphasise the complexity of light perception in this echinoderm class. PMID:27119739
A preview of a modular surface light scattering instrument with autotracking optics
NASA Technical Reports Server (NTRS)
Meyer, William V.; Tin, Padetha; Mann, J. Adin, Jr.; Cheung, H. Michael; Rogers, Richard B.; Lading, Lars
1994-01-01
NASA's Advanced Technology Development (ATD) program is sponsoring the development of a new generation of surface light scattering hardware. This instrument is designed to non-invasively measure the surface response function of liquids over a wide range of operating conditions while automatically compensating for a sloshing surface. The surface response function can be used to compute surface tension, properties of monolayers present, viscosity, surface tension gradient and surface temperature. The instrument uses optical and electronic building blocks developed for the laser light scattering program at NASA Lewis along with several unique surface light scattering components. The emphasis of this paper is the compensation for bulk surface motion (slosh). Some data processing background information is also included.
Lacey, Steven E.; Vesper, Benjamin J.; Paradise, William A.; Radosevich, James A.; Colvard, Michael D.
2013-01-01
Abstract Objective: Photodynamic therapy (PDT) as a medical treatment for cancers is an increasing practice in clinical settings, as new photosensitizing chemicals and light source technologies are developed and applied. PDT involves dosing patients with photosensitizing drugs, and then exposing them to light using a directed energy device in order to manifest a therapeutic effect. Healthcare professionals providing PDT should be aware of potential occupational health and safety hazards posed by these treatment devices and photosensitizing agents administered to patients. Materials and methods: Here we outline and identify pertinent health and safety considerations to be taken by healthcare staff during PDT procedures. Results: Physical hazards (for example, non-ionizing radiation generated by the light-emitting device, with potential for skin and eye exposure) and chemical hazards (including the photosensitizing agents administered to patients that have the potential for exposure via skin, subcutaneous, ingestion, or inhalation routes) must be considered for safe use of PDT by the healthcare professional. Conclusions: Engineering, administrative, and personal protective equipment controls are recommendations for the safe use and handling of PDT agents and light-emitting technologies. PMID:23859750
NASA Astrophysics Data System (ADS)
Wang, Yao; Zhang, Qingtao; Sun, Yuan; Yang, Chengjia
2018-01-01
As a new generation biodiesel feedstock, microalgae have most potential to replace fossil fuel. However, the limited scale and high cost are two bottleneck problems. Efficient microwave-assisted lipid extraction technologies and suitable light conditions for Chlorella Sorokiniana need further study for lowering the cost. In this study, three photoperiod groups(24L:0D, 12L:12D, 0L:24D), three illumination intensity groups (1800 lux, 3600 lux, 5400 lux)and four light spectrum groups (Red, green, blue, and white) were used to culture Chlorella Sorokiniana to investigate those effects on algae growth rate and biomass accumulation. The suitable microwave treatment was also studied to achieve an optimizing quantum fracturing technology. 400 w, 750 w and 1000 w microwave power were set and 60 °C, 75 °C, 90 °C microwave conditions were investigated. The results showed that Chlorella Sorokiniana under 24L:0D photoperiod with 5400 lux white light can achieve better growth rate. The 90 °C / 1000w microwave treatment was identified as the most simple, easy, and effective way for lipid extraction from Chlorella Sorokiniana. As the raw material of biodiesel production, C18:1, C18:2 and C18:3 have accounted for important components of fatty acid in Chlorella Sorokiniana. Therefore, Chlorella Sorokiniana is a good raw material for the production of good quality biodiesel under suitable and efficient technologies.
TADIR: a second-generation 480 x 4 TDI FLIR
NASA Astrophysics Data System (ADS)
Sarusi, Gabby
1997-08-01
'TADIR' is an El-Op's new second generation thermal imager based on 480 by 4 TDI MCT detector operated in the 8 - 10.5 micrometer spectral range. Although the prototype configuration design of TADIR is aimed toward the light weight low volume applications, TADIR is a generic modular technology of which the future El-Op second generation FLIR applications will be derived from. Beside the detector, what put the system in the second generation category are the state of the art features implemented in every component. This paper describes the system concept and design consideration have been taken during the development of its components.
Bragg-Berry mirrors: reflective broadband q-plates.
Rafayelyan, Mushegh; Brasselet, Etienne
2016-09-01
We report on the experimental realization of flat mirrors enabling the broadband generation of optical vortices upon reflection. The effect is based on the geometric Berry phase associated with the circular Bragg reflection phenomenon from chiral uniaxial media. We show the reflective optical vortex generation from both diffractive and nondiffractive paraxial light beams using spatially patterned chiral liquid crystal films. The intrinsic spectrally broadband character of spin-orbit generation of optical phase singularities is demonstrated over the full visible domain. Our results do not rely on any birefringent retardation requirement and, consequently, foster the development of a novel generation of robust optical elements for spin-orbit photonic technologies.
NASA Astrophysics Data System (ADS)
Ma, Chaoyang; Cao, Yongge; Shen, Xiaofei; Wen, Zicheng; Ma, Ran; Long, Jiaqi; Yuan, Xuanyi
2017-07-01
Nowadays, major commercial w-LEDs fabricated by the traditionally gold-wire-welding packaging technology have undergone considerable development as indoor/outdoor lighting sources due to its high-energy utilization efficiency, long service life, environmental friendliness, and excellent chromatic stability. While, new generation applications in projections, automotive lighting, street lighting, plaza lighting, and high-end general lighting need further improvements in power handling and light extraction. Herein, transparent Ce:YAG glass-ceramics (GCs) phosphor was prepared by low-temperature co-sintering polycrystalline Ce:YAG phosphor powder and home-made PbO-B2O3-ZnO-SiO2 glass powder. Thereafter, the flip-chip (FC) w-LEDs were fabricated with the GCs phosphor plates and FC blue chips. The GCs-based FC w-LEDs show not only excellent heat- and humidity-resistance characteristics, but also superior optical performances with an LE of 112.8 lm/W, a CRI of 71.2, a CCT of 6103 K as well as a chromaticity coordinate of (0.3202, 0.3298), under a high operation current of 400 mA. The technology route will open a practically commercial feasible approach to achieve excellent performances for advanced high-power FC w-LEDs.
Carver-Brown, Rachel K.; Reis, Arthur H.; Rice, Lisa M.; Czajka, John W.; Wangh, Lawrence J.
2012-01-01
Aims. The goal of this study was to construct a single tube molecular diagnostic multiplex assay for the detection of microbial pathogens commonly associated with septicemia, using LATE-PCR and Lights-On/Lights-Off probe technology. Methods and Results. The assay described here identified pathogens associated with sepsis by amplification and analysis of the 16S ribosomal DNA gene sequence for bacteria and specific gene sequences for fungi. A sequence from an unidentified gene in Lactococcus lactis subsp. cremoris served as a positive control for assay function. LATE-PCR was used to generate single-stranded amplicons that were then analyzed at endpoint over a wide temperature range in a specific fluorescent color. Each bacterial target was identified by its pattern of hybridization to Lights-On/Lights-Off probes derived from molecular beacons. Complex mixtures of targets were also detected. Conclusions. All microbial targets were identified in samples containing low starting copy numbers of pathogen genomic DNA, both as individual targets and in complex mixtures. Significance and Impact of the Study. This assay uses new technology to achieve an advance in the field of molecular diagnostics: a single-tube multiplex assay for identification of pathogens commonly associated with sepsis. PMID:23326668
Federal Register 2010, 2011, 2012, 2013, 2014
2012-08-02
... for generating power for all the in-flight systems that run on electricity, including pumping breathable air into the fuselage, operating the lights, and running the navigation and communication... turning a propeller blade on a turboprop engine, a rotor shaft on a turboshaft engine, or a fan in front...
/Start technology conserves energy by shutting off the gasoline engine when the vehicle is at rest, such as at a traffic light, and automatically re-starting it when the driver pushes the gas pedal to go engine when pulling out from a stop and generating electricity which is stored in the battery. Main stage
PhotoMorphs™: A Novel Light-Activated Reagent for Controlling Gene Expression in Zebrafish
Tomasini, Amber J.; Schuler, Aaron D.; Zebala, John A.; Mayer, Alan N.
2009-01-01
Manipulating gene expression in zebrafish is critical for exploiting the full potential of this vertebrate model organism. Morpholino oligos are the most commonly employed antisense technology for knocking down gene expression. However, morpholinos suffer from a lack of control over the timing and location of knockdown. In this report, we describe a novel light-activatable knockdown reagent called PhotoMorph™. PhotoMorphs can be generated from existing morpholinos by hybridization with a complementary caging strand containing a photocleavable linkage. The caging strand neutralizes the morpholino activity until irradiation of the PhotoMorph with UV light releases the morpholino. We generated PhotoMorphs to target genes encoding enhanced green fluorescent protein (EGFP), No tail, and E-cadherin to illustrate the utility of this approach. Temporal control of gene expression with PhotoMorphs permitted us to circumvent the early lethal phenotype of E-cadherin knockdown. A splice-blocking PhotoMorph directed to the rheb gene showed light-dependent gene knockdown up to 72 hpf. PhotoMorphs thus offer a new class of laboratory reagents suitable for the spatiotemporal control of gene expression in the zebrafish. PMID:19644983
Taheri, M.; Darabyan, M.; Izadbakhsh, E.; Nouri, F.; Haghani, M.; Mortazavi, S.A.R.; Mortazavi, G.; Mortazavi, S.M.J.; Moradi, M.
2017-01-01
Background: Due to rapid advances in modern technologies such as telecommunication technology, the world has witnessed an exponential growth in the use of digital handheld devices (e.g. smartphones and tablets). This drastic growth has resulted in increased global concerns about the safety of these devices. Smartphones, tablets, laptops, and other digital screens emit high levels of short-wavelength visible light (i.e. blue color region in the visible light spectrum). Material and Methods: At a dark environment, Staphylococcus aureus bacteria were exposed to the light emitted from common tablets/smartphones. The control samples were exposed to the same intensity of light generated by a conventional incandescent light bulb. The growth rate of bacteria was examined by measuring the optical density (OD) at 625 nm by using a spectrophotometer before the light exposure and after 30 to 330 minutes of light exposure. Results: The growth rates of bacteria in both smartphone and tablet groups were higher than that of the control group and the maximum smartphone/control and tablet/control growth ratios were observed in samples exposed to digital screens’ light for 300 min (ratios of 3.71 and 3.95, respectively). Conclusion: To the best of our knowledge, this is the first study that investigates the effect of exposure to light emitted from digital screens on the proliferation of Staphylococcus aureus and its association with acne pathogenesis. Our findings show that exposure to short-wavelength visible light emitted from smartphones and tablets can increase the proliferation of Staphylococcus aureus. PMID:28580338
Next generation smart window display using transparent organic display and light blocking screen.
Kim, Gyeong Woo; Lampande, Raju; Choe, Dong Cheol; Ko, Ik Jang; Park, Jin Hwan; Pode, Ramchandra; Kwon, Jang Hyuk
2018-04-02
Transparent organic light emitting diodes (TOLED) have widespread applications in the next-generation display devices particularly in the large size transparent window and interactive displays. Herein, we report high performance and stable attractive smart window displays using facile process. Advanced smart window display is realized by integrating the high performance light blocking screen and highly transparent white OLED panel. The full smart window display reveals a maximum transmittance as high as 64.2% at the wavelength of 600 nm and extremely good along with tunable ambient contrast ratio (171.94:1) compared to that of normal TOLED (4.54:1). Furthermore, the performance decisive light blocking screen has demonstrated an excellent optical and electrical characteristics such as i) high transmittance (85.56% at 562nm) at light-penetrating state, ii) superior absorbance (2.30 at 562nm) in light interrupting mode, iii) high optical contrast (85.50 at 562 nm), iv) high optical stability for more than 25,000 cycle of driving, v) fast switching time of 1.9 sec, and vi) low driving voltage of 1.7 V. The experimental results of smart window display are also validated using optical simulation. The proposed smart window display technology allows us to adjust the intensity of daylight entering the system quickly and conveniently.
Tomb, Rachael M; Maclean, Michelle; Coia, John E; Graham, Elizabeth; McDonald, Michael; Atreya, Chintamani D; MacGregor, Scott J; Anderson, John G
2017-06-01
The requirement for novel decontamination technologies for use in hospitals is ever present. One such system uses 405 nm visible light to inactivate microorganisms via ROS-generated oxidative damage. Although effective for bacterial and fungal inactivation, little is known about the virucidal effects of 405 nm light. Norovirus (NoV) gastroenteritis outbreaks often occur in the clinical setting, and this study was designed to investigate potential inactivation effects of 405 nm light on the NoV surrogate, feline calicivirus (FCV). FCV was exposed to 405 nm light whilst suspended in minimal and organically-rich media to establish the virucidal efficacy and the effect biologically-relevant material may play in viral susceptibility. Antiviral activity was successfully demonstrated with a 4 Log 10 (99.99%) reduction in infectivity when suspended in minimal media evident after a dose of 2.8 kJ cm -2 . FCV exposed in artificial faeces, artificial saliva, blood plasma and other organically rich media exhibited an equivalent level of inactivation using between 50-85% less dose of the light, indicating enhanced inactivation when the virus is present in organically-rich biologically-relevant media. Further research in this area could aid in the development of 405 nm light technology for effective NoV decontamination within the hospital environment.
REVIEWS OF TOPICAL PROBLEMS: Spiral light beams
NASA Astrophysics Data System (ADS)
Abramochkin, Evgenii G.; Volostnikov, Vladimir G.
2004-12-01
This paper discusses theoretical and experimental results of the investigation of light beams that retain their intensity strusture during propagation and focusing. We describe a family of laser beams termed spiral whose intensity remains invariable, up to scale and rotation, during propagation. Several properties of spiral beams are of practical interest for laser technologies, medicine, and microbiology. The problem of synthesis of spiral beams with the intensity distribution given by an arbitrary planar curve is considered. We emphasize the feasibility, in principle, of making lasers that directly generate beams with desired properties without additional unconventional optics.
Optical design and development of a snapshot light-field laryngoscope
NASA Astrophysics Data System (ADS)
Zhu, Shuaishuai; Jin, Peng; Liang, Rongguang; Gao, Liang
2018-02-01
The convergence of recent advances in optical fabrication and digital processing yields a generation of imaging technology-light-field (LF) cameras which bridge the realms of applied mathematics, optics, and high-performance computing. Herein for the first time, we introduce the paradigm of LF imaging into laryngoscopy. The resultant probe can image the three-dimensional shape of vocal folds within a single camera exposure. Furthermore, to improve the spatial resolution, we developed an image fusion algorithm, providing a simple solution to a long-standing problem in LF imaging.
NASA Astrophysics Data System (ADS)
Buske, Ivo; Riede, Wolfgang
2006-09-01
We compare active optical elements based on different technologies to accomplish the requirements of a 2-dim. fine tracking control system. A cascaded optically and electrically addressable spatial light modulator (OASLM) based on liquid crystals (LC) is used for refractive beam steering. Spatial light modulators provide a controllable phase wedge to generate a beam deflection. Additionally, a tip/tilt mirror approach operating with piezo-electric actuators is investigated. A digital PID controller is implemented for closed-loop control. Beam tracking with a root-mean-squared accuracy of Δα=30 nrad has been laboratory-confirmed.
NASA Technical Reports Server (NTRS)
1986-01-01
The FluoroScan Imaging System is a high resolution, low radiation device for viewing stationary or moving objects. It resulted from NASA technology developed for x-ray astronomy and Goddard application to a low intensity x-ray imaging scope. FlouroScan Imaging Systems, Inc, (formerly HealthMate, Inc.), a NASA licensee, further refined the FluoroScan System. It is used for examining fractures, placement of catheters, and in veterinary medicine. Its major components include an x-ray generator, scintillator, visible light image intensifier and video display. It is small, light and maneuverable.
NASA Astrophysics Data System (ADS)
Huh, Jae-Won; Yu, Byeong-Hun; Shin, Dong-Myung; Yoon, Tae-Hoon
2015-03-01
Recently, a transparent display has got much attention as one of the next generation display devices. Especially, active studies on a transparent display using organic light-emitting diodes (OLEDs) are in progress. However, since it is not possible to obtain black color using a transparent OLED, it suffers from poor visibility. This inevitable problem can be solved by using a light shutter. Light shutter technology can be divided into two types; light absorption and scattering. However, a light shutter based on light absorption cannot block the background image perfectly and a light shutter based on light scattering cannot provide black color. In this work we demonstrate a light shutter using two liquid crystal (LC) layers, a light absorption layer and a light scattering layer. To realize a light absorption layer and a light scattering layer, we use the planar state of a dye-doped chiral nematic LC (CNLC) cell and the focal-conic state of a long-pitch CNLC cell, respectively. The proposed light shutter device can block the background image perfectly and show black color. We expect that the proposed light shutter can increase the visibility of a transparent display.
On-Chip Waveguide Coupling of a Layered Semiconductor Single-Photon Source.
Tonndorf, Philipp; Del Pozo-Zamudio, Osvaldo; Gruhler, Nico; Kern, Johannes; Schmidt, Robert; Dmitriev, Alexander I; Bakhtinov, Anatoly P; Tartakovskii, Alexander I; Pernice, Wolfram; Michaelis de Vasconcellos, Steffen; Bratschitsch, Rudolf
2017-09-13
Fully integrated quantum technology based on photons is in the focus of current research, because of its immense potential concerning performance and scalability. Ideally, the single-photon sources, the processing units, and the photon detectors are all combined on a single chip. Impressive progress has been made for on-chip quantum circuits and on-chip single-photon detection. In contrast, nonclassical light is commonly coupled onto the photonic chip from the outside, because presently only few integrated single-photon sources exist. Here, we present waveguide-coupled single-photon emitters in the layered semiconductor gallium selenide as promising on-chip sources. GaSe crystals with a thickness below 100 nm are placed on Si 3 N 4 rib or slot waveguides, resulting in a modified mode structure efficient for light coupling. Using optical excitation from within the Si 3 N 4 waveguide, we find nonclassicality of generated photons routed on the photonic chip. Thus, our work provides an easy-to-implement and robust light source for integrated quantum technology.
Separated carbon nanotube macroelectronics for active matrix organic light-emitting diode displays.
Zhang, Jialu; Fu, Yue; Wang, Chuan; Chen, Po-Chiang; Liu, Zhiwei; Wei, Wei; Wu, Chao; Thompson, Mark E; Zhou, Chongwu
2011-11-09
Active matrix organic light-emitting diode (AMOLED) display holds great potential for the next generation visual technologies due to its high light efficiency, flexibility, lightweight, and low-temperature processing. However, suitable thin-film transistors (TFTs) are required to realize the advantages of AMOLED. Preseparated, semiconducting enriched carbon nanotubes are excellent candidates for this purpose because of their excellent mobility, high percentage of semiconducting nanotubes, and room-temperature processing compatibility. Here we report, for the first time, the demonstration of AMOLED displays driven by separated nanotube thin-film transistors (SN-TFTs) including key technology components, such as large-scale high-yield fabrication of devices with superior performance, carbon nanotube film density optimization, bilayer gate dielectric for improved substrate adhesion to the deposited nanotube film, and the demonstration of monolithically integrated AMOLED display elements with 500 pixels driven by 1000 SN-TFTs. Our approach can serve as the critical foundation for future nanotube-based thin-film display electronics.
Separated Carbon Nanotube Macroelectronics for Active Matrix Organic Light-Emitting Diode Displays
NASA Astrophysics Data System (ADS)
Fu, Yue; Zhang, Jialu; Wang, Chuan; Chen, Pochiang; Zhou, Chongwu
2012-02-01
Active matrix organic light-emitting diode (AMOLED) display holds great potential for the next generation visual technologies due to its high light efficiency, flexibility, lightweight, and low-temperature processing. However, suitable thin-film transistors (TFTs) are required to realize the advantages of AMOLED. Pre-separated, semiconducting enriched carbon nanotubes are excellent candidates for this purpose because of their excellent mobility, high percentage of semiconducting nanotubes, and room-temperature processing compatibility. Here we report, for the first time, the demonstration of AMOLED displays driven by separated nanotube thin-film transistors (SN-TFTs) including key technology components such as large-scale high-yield fabrication of devices with superior performance, carbon nanotube film density optimization, bilayer gate dielectric for improved substrate adhesion to the deposited nanotube film, and the demonstration of monolithically integrated AMOLED display elements with 500 pixels driven by 1000 SN-TFTs. Our approach can serve as the critical foundation for future nanotube-based thin-film display electronics.
Joint Non-Lethal Weapons Program Science and Technology Strategic Plan
2016-03-31
compact technology for sound generation using advanced materials Active Denial Technology (ADT) Future active denial technology system concept...investment objectives in human effects research, conducted energy weapons (human electro‐muscular incapacitation), and sound and light that will advance...advancing the development of megawatt class waveguides and rotary joints, innovative dielectrics and insulators , and on the characterization of
An Overview of Space Power Systems for NASA Missions
NASA Technical Reports Server (NTRS)
Lyons, Valerie J.; Scott, John H.
2007-01-01
Power is a critical commodity for all engineering efforts and is especially challenging in the aerospace field. This paper will provide a broad brush overview of some of the immediate and important challenges to NASA missions in the field of aerospace power, for generation, energy conversion, distribution, and storage. NASA s newest vehicles which are currently in the design phase will have power systems that will be developed from current technology, but will have the challenges of being light-weight, energy-efficient, and space-qualified. Future lunar and Mars "outposts" will need high power generation units for life support and energy-intensive exploration efforts. An overview of the progress in concepts for power systems and the status of the required technologies are discussed.
NASA Astrophysics Data System (ADS)
Fu, Qiang; Gao, Duorui; Liu, Zhi; Chen, Chunyi; Lou, Yan; Jiang, Huilin
2014-11-01
Based on partially coherent polarized light transmission characteristics of the atmosphere, an intensity expression of completely coherent flashing light is derived from Andrews scale modulation method. According to the generalized Huygens-Fresnel principle and Rytov theory, the phase fluctuation structure function is obtained on condition that the refractive index profile in the atmosphere meet Von Karman spectrum, then get the arrival Angle fluctuation variance. Through the RMS beam width of gaussian beams in turbulent atmosphere, deviation angle formula of fully coherent gaussian beams in turbulence atmosphere is attained, then get the RMS beam width of partially coherent and derivation angle expression of GSM beam in turbulent atmosphere. Combined with transmission properties of radial polarized laser beam, cross spectral density matrix of partially coherent radially polarized light can be gained by using generalized huygens-fresnel principle. And light intensity and polarization after transmission can be known according to the unity of coherence and polarization theory. On the basis of the analysis model and numerical simulation, the simulation results show that: the light spot caused by atmospheric turbulence of partially coherent polarization will be superior to completely polarized light.Taking advantage of this feature, designed a new wireless suppression technology of atmospheric turbulence, that is the optimization criterion of initial degree of coherent light beam. The optimal initial degree of coherent light beam will change along with the change of atmospheric turbulence conditions,make control the beam's initial degree of coherence to realize the initial degree of coherence of light beam in real time and dynamic control. A spatial phase screen before emission aperture of fully coherent light is to generate the partially coherent light, liquid crystal spatial light modulator is is a preferable way to realize the dynamic random phase. Finally look future of the application research of partially coherent light.
Hardware-in-the-loop projector system for light detection and ranging sensor testing
NASA Astrophysics Data System (ADS)
Kim, Hajin J.; Naumann, Charles B.; Cornell, Michael C.
2012-08-01
Efforts in developing a synthetic environment for testing light detection and ranging (LADAR) sensors in a hardware-in-the-loop simulation are continuing at the Aviation and Missile Research, Engineering, and Development Center of the U.S. Army Research, Engineering and Development Command (RDECOM). Current activities have concentrated on evaluating the optical projection techniques for the LADAR synthetic environment. Schemes for generating the optical signals representing the individual pixels of the projection are of particular interest. Several approaches have been investigated and tested with emphasis on operating wavelength, intensity dynamic range and uniformity, and flexibility in pixel waveform generation. This paper will discuss some of the results from these current efforts at RDECOM's System Simulation and Development Directorate's Electro Optical Technology Development Laboratory.
X-ray detectors at the Linac Coherent Light Source.
Blaj, Gabriel; Caragiulo, Pietro; Carini, Gabriella; Carron, Sebastian; Dragone, Angelo; Freytag, Dietrich; Haller, Gunther; Hart, Philip; Hasi, Jasmine; Herbst, Ryan; Herrmann, Sven; Kenney, Chris; Markovic, Bojan; Nishimura, Kurtis; Osier, Shawn; Pines, Jack; Reese, Benjamin; Segal, Julie; Tomada, Astrid; Weaver, Matt
2015-05-01
Free-electron lasers (FELs) present new challenges for camera development compared with conventional light sources. At SLAC a variety of technologies are being used to match the demands of the Linac Coherent Light Source (LCLS) and to support a wide range of scientific applications. In this paper an overview of X-ray detector design requirements at FELs is presented and the various cameras in use at SLAC are described for the benefit of users planning experiments or analysts looking at data. Features and operation of the CSPAD camera, which is currently deployed at LCLS, are discussed, and the ePix family, a new generation of cameras under development at SLAC, is introduced.
X-ray detectors at the Linac Coherent Light Source
DOE Office of Scientific and Technical Information (OSTI.GOV)
Blaj, Gabriel; Caragiulo, Pietro; Carini, Gabriella
Free-electron lasers (FELs) present new challenges for camera development compared with conventional light sources. At SLAC a variety of technologies are being used to match the demands of the Linac Coherent Light Source (LCLS) and to support a wide range of scientific applications. In this paper an overview of X-ray detector design requirements at FELs is presented and the various cameras in use at SLAC are described for the benefit of users planning experiments or analysts looking at data. Features and operation of the CSPAD camera, which is currently deployed at LCLS, are discussed, and the ePix family, a newmore » generation of cameras under development at SLAC, is introduced.« less
X-ray detectors at the Linac Coherent Light Source
Blaj, Gabriel; Caragiulo, Pietro; Carini, Gabriella; ...
2015-04-21
Free-electron lasers (FELs) present new challenges for camera development compared with conventional light sources. At SLAC a variety of technologies are being used to match the demands of the Linac Coherent Light Source (LCLS) and to support a wide range of scientific applications. In this paper an overview of X-ray detector design requirements at FELs is presented and the various cameras in use at SLAC are described for the benefit of users planning experiments or analysts looking at data. Features and operation of the CSPAD camera, which is currently deployed at LCLS, are discussed, and the ePix family, a newmore » generation of cameras under development at SLAC, is introduced.« less
JPRS report: Science and technology. Central Eurasia: Physics and mathematics
NASA Astrophysics Data System (ADS)
1993-11-01
Translated articles cover the following topics: laser-acoustic cleaning of surfaces from mechanical microparticles; supersonic CO laser with HF excitation in combustion products; possibility of use of interaction between acoustic and light waves in fiber light conductors for generation of short light pulses; steady three-dimensional flow of viscous gas through channels and nozzles; current fluctuations in superconductor with superlattice in strong electric and magnetic fields; influence of strong electric field on conductivity of high-temperature superconductor ceramic of YBaCuO system; effect of electron bombardment on peak-effect in YBa2 Cu3Ox single crystals; and evolution of homogeneous isotropic universe, dark mass, and absence of monopoles.
X-ray detectors at the Linac Coherent Light Source
Blaj, Gabriel; Caragiulo, Pietro; Carini, Gabriella; Carron, Sebastian; Dragone, Angelo; Freytag, Dietrich; Haller, Gunther; Hart, Philip; Hasi, Jasmine; Herbst, Ryan; Herrmann, Sven; Kenney, Chris; Markovic, Bojan; Nishimura, Kurtis; Osier, Shawn; Pines, Jack; Reese, Benjamin; Segal, Julie; Tomada, Astrid; Weaver, Matt
2015-01-01
Free-electron lasers (FELs) present new challenges for camera development compared with conventional light sources. At SLAC a variety of technologies are being used to match the demands of the Linac Coherent Light Source (LCLS) and to support a wide range of scientific applications. In this paper an overview of X-ray detector design requirements at FELs is presented and the various cameras in use at SLAC are described for the benefit of users planning experiments or analysts looking at data. Features and operation of the CSPAD camera, which is currently deployed at LCLS, are discussed, and the ePix family, a new generation of cameras under development at SLAC, is introduced. PMID:25931071
Parallel Polarization State Generation
NASA Astrophysics Data System (ADS)
She, Alan; Capasso, Federico
2016-05-01
The control of polarization, an essential property of light, is of wide scientific and technological interest. The general problem of generating arbitrary time-varying states of polarization (SOP) has always been mathematically formulated by a series of linear transformations, i.e. a product of matrices, imposing a serial architecture. Here we show a parallel architecture described by a sum of matrices. The theory is experimentally demonstrated by modulating spatially-separated polarization components of a laser using a digital micromirror device that are subsequently beam combined. This method greatly expands the parameter space for engineering devices that control polarization. Consequently, performance characteristics, such as speed, stability, and spectral range, are entirely dictated by the technologies of optical intensity modulation, including absorption, reflection, emission, and scattering. This opens up important prospects for polarization state generation (PSG) with unique performance characteristics with applications in spectroscopic ellipsometry, spectropolarimetry, communications, imaging, and security.
NASA Astrophysics Data System (ADS)
Sun, Yongjian; Trieu, Simeon; Yu, Tongjun; Chen, Zhizhong; Qi, Shengli; Tian, Pengfei; Deng, Junjing; Jin, Xiaoming; Zhang, Guoyi
2011-08-01
Vertical structure LEDs have been fabricated with a novel light extraction composite surface structure composed of a micron grating and nano-structure. The composite surface structure was generated by using a modified YAG laser lift-off technique, separating the wafers from cone-shaped patterned sapphire substrates. LEDs thus fabricated showed the light output power increase about 1.7-2.5 times when compared with conventional vertical structure LEDs grown on plane sapphire substrates. A three-dimensional finite difference time domain method was used to simulate this new kind of LED device. It was determined that nano-structures in composite surface patterns play a key role in the improvement of light extraction efficiency of LEDs.
Evaluation of Gas Chromatography/Mini-IMS to Detect VOCs
NASA Technical Reports Server (NTRS)
Limero, Thomas; Reese, Eric; Peters, Randy; James, John T.; Billica, Roger (Technical Monitor)
1999-01-01
The Toxicology Laboratory at Johnson Space Center (JSC) has pioneered the use of gas chromatography-ion mobility spectrometry (GC/IMS) for measuring target volatile organic compounds (VOCs) aboard spacecraft. Graseby Dynamics, under contract to NASA/Wyle, has built several volatile organic analyzers (VOA) based on GC/IMS. Foremost among these have been the volatile organic analyzer-risk mitigation unit and the two flight VOA units for International Space Station (ISS). The development and evaluation of these instruments has been chronicled through presentations at the International Conference on Ion Mobility Spectrometry over the past three years. As the flight VOA from Graseby is prepared for operation on ISS at JSC, it is time to begin evaluations of technologies for the next generation VOA, Although the desired instrument characteristics for the next generation unit are the same as the current unit, the requirements are much more stringent. As NASA looks toward future missions beyond Earth environs, a premium will be placed upon small, light, reliable, autonomous hardware. It is with these visions in mind that the JSC Toxicology Laboratory began a search for the next generation VOA. One technology that is a candidate for the next generation VOA is GC/IMS. The recent miniaturization of IMS technology permits it to compete with other, inherently small, technologies such as chip-sized sensor arrays. This paper will discuss the lessons learned from the VOA experience and how that has shaped the design of a potential second generation VOA based upon GC/IMS technology. Data will be presented from preliminary evaluations of GC technology and the mini-IMS when exposed to VOCs likely to be detected aboard spacecraft. Results from the evaluation of an integrated GC/mini-IMS system will be shown if available.
Technology Pathway Partnership Final Scientific Report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hall, John C. Dr.; Godby, Larry A.
2012-04-26
This report covers the scientific progress and results made in the development of high efficiency multijunction solar cells and the light concentrating non-imaging optics for the commercial generation of renewable solar energy. During the contract period the efficiency of the multijunction solar cell was raised from 36.5% to 40% in commercially available fully qualified cells. In addition significant strides were made in automating production process for these cells in order to meet the costs required to compete with commercial electricity. Concurrent with the cells effort Boeing also developed a non imaging optical systems to raise the light intensity at themore » photovoltaic cell to the rage of 800 to 900 suns. Solar module efficiencies greater than 30% were consistently demonstrated. The technology and its manufacturing were maturated to a projected price of < $0.015 per kWh and demonstrated by automated assembly in a robotic factory with a throughput of 2 MWh/yr. The technology was demonstrated in a 100 kW power plant erected at California State University Northridge, CA.« less
Advanced optical instruments technology
NASA Technical Reports Server (NTRS)
Shao, Mike; Chrisp, Michael; Cheng, Li-Jen; Eng, Sverre; Glavich, Thomas; Goad, Larry; Jones, Bill; Kaarat, Philip; Nein, Max; Robinson, William
1992-01-01
The science objectives for proposed NASA missions for the next decades push the state of the art in sensitivity and spatial resolution over a wide range of wavelengths, including the x-ray to the submillimeter. While some of the proposed missions are larger and more sensitive versions of familiar concepts, such as the next generation space telescope, others use concepts, common on the Earth, but new to space, such as optical interferometry, in order to provide spatial resolutions impossible with other concepts. However, despite their architecture, the performance of all of the proposed missions depends critically on the back-end instruments that process the collected energy to produce scientifically interesting outputs. The Advanced Optical Instruments Technology panel was chartered with defining technology development plans that would best improve optical instrument performance for future astrophysics missions. At this workshop the optical instrument was defined as the set of optical components that reimage the light from the telescope onto the detectors to provide information about the spatial, spectral, and polarization properties of the light. This definition was used to distinguish the optical instrument technology issues from those associated with the telescope, which were covered by a separate panel. The panel identified several areas for optical component technology development: diffraction gratings; tunable filters; interferometric beam combiners; optical materials; and fiber optics. The panel also determined that stray light suppression instruments, such as coronagraphs and nulling interferometers, were in need of general development to support future astrophysics needs.
Advanced optical instruments technology
NASA Astrophysics Data System (ADS)
Shao, Mike; Chrisp, Michael; Cheng, Li-Jen; Eng, Sverre; Glavich, Thomas; Goad, Larry; Jones, Bill; Kaarat, Philip; Nein, Max; Robinson, William
1992-08-01
The science objectives for proposed NASA missions for the next decades push the state of the art in sensitivity and spatial resolution over a wide range of wavelengths, including the x-ray to the submillimeter. While some of the proposed missions are larger and more sensitive versions of familiar concepts, such as the next generation space telescope, others use concepts, common on the Earth, but new to space, such as optical interferometry, in order to provide spatial resolutions impossible with other concepts. However, despite their architecture, the performance of all of the proposed missions depends critically on the back-end instruments that process the collected energy to produce scientifically interesting outputs. The Advanced Optical Instruments Technology panel was chartered with defining technology development plans that would best improve optical instrument performance for future astrophysics missions. At this workshop the optical instrument was defined as the set of optical components that reimage the light from the telescope onto the detectors to provide information about the spatial, spectral, and polarization properties of the light. This definition was used to distinguish the optical instrument technology issues from those associated with the telescope, which were covered by a separate panel. The panel identified several areas for optical component technology development: diffraction gratings; tunable filters; interferometric beam combiners; optical materials; and fiber optics. The panel also determined that stray light suppression instruments, such as coronagraphs and nulling interferometers, were in need of general development to support future astrophysics needs.
Durrant, James R
2013-08-13
This review starts with a brief overview of the technological potential of molecular-based solar cell technologies. It then goes on to focus on the core scientific challenge associated with using molecular light-absorbing materials for solar energy conversion, namely the separation of short-lived, molecular-excited states into sufficiently long-lived, energetic, separated charges capable of generating an external photocurrent. Comparisons are made between different molecular-based solar cell technologies, with particular focus on the function of dye-sensitized photoelectrochemical solar cells as well as parallels with the function of photosynthetic reaction centres. The core theme of this review is that generating charge carriers with sufficient lifetime and a high quantum yield from molecular-excited states comes at a significant energetic cost-such that the energy stored in these charge-separated states is typically substantially less than the energy of the initially generated excited state. The role of this energetic loss in limiting the efficiency of solar energy conversion by such devices is emphasized, and strategies to minimize this energy loss are compared and contrasted.
Molecular optoelectronics: the interaction of molecular conduction junctions with light.
Galperin, Michael; Nitzan, Abraham
2012-07-14
The interaction of light with molecular conduction junctions is attracting growing interest as a challenging experimental and theoretical problem on one hand, and because of its potential application as a characterization and control tool on the other. It stands at the interface between two important fields, molecular electronics and molecular plasmonics and has attracted attention as a challenging scientific problem with potentially important technological consequences. Here we review the present state of the art of this field, focusing on several key phenomena and applications: using light as a switching device, using light to control junction transport in the adiabatic and non-adiabatic regimes, light generation in biased junctions and Raman scattering from such systems. This field has seen remarkable progress in the past decade, and the growing availability of scanning tip configurations that can combine optical and electrical probes suggests that further progress towards the goal of realizing molecular optoelectronics on the nanoscale is imminent.
Liang, Xiao; Chen, Mei; Guo, Shumeng; Zhang, Lanying; Li, Fasheng; Yang, Huai
2017-11-22
Smart windows with controllable visible and near-infrared light transmittance can significantly improve the building's energy efficiency and inhabitant comfort. However, most of the current smart window technology cannot achieve the target of ideal solar control. Herein, we present a novel all-solution-processed hybrid micronano composite smart material that have four optical states to separately modulate the visible and NIR light transmittance through voltage and temperature, respectively. This dual-band optical modulation was achieved by constructing a phase-separated polymer framework, which contains the microsized liquid crystals domains with a negative dielectric constant and tungsten-doped vanadium dioxide (W-VO 2 ) nanocrystals (NCs). The film with 2.5 wt % W-VO 2 NCs exhibits transparency at normal condition, and the passage of visible light can be reversibly and actively regulated between 60.8% and 1.3% by external applied voltage. Also, the transmittance of NIR light can be reversibly and passively modulated between 59.4% and 41.2% by temperature. Besides, the film also features easy all-solution processability, fast electro-optical (E-O) response time, high mechanical strength, and long-term stability. The as-prepared film provides new opportunities for next-generation smart window technology, and the proposed strategy is conductive to engineering novel hybrid inorganic-organic functional matters.
Fluorescent signatures for variable DNA sequences
Rice, John E.; Reis, Arthur H.; Rice, Lisa M.; Carver-Brown, Rachel K.; Wangh, Lawrence J.
2012-01-01
Life abounds with genetic variations writ in sequences that are often only a few hundred nucleotides long. Rapid detection of these variations for identification of genetic diseases, pathogens and organisms has become the mainstay of molecular science and medicine. This report describes a new, highly informative closed-tube polymerase chain reaction (PCR) strategy for analysis of both known and unknown sequence variations. It combines efficient quantitative amplification of single-stranded DNA targets through LATE-PCR with sets of Lights-On/Lights-Off probes that hybridize to their target sequences over a broad temperature range. Contiguous pairs of Lights-On/Lights-Off probes of the same fluorescent color are used to scan hundreds of nucleotides for the presence of mutations. Sets of probes in different colors can be combined in the same tube to analyze even longer single-stranded targets. Each set of hybridized Lights-On/Lights-Off probes generates a composite fluorescent contour, which is mathematically converted to a sequence-specific fluorescent signature. The versatility and broad utility of this new technology is illustrated in this report by characterization of variant sequences in three different DNA targets: the rpoB gene of Mycobacterium tuberculosis, a sequence in the mitochondrial cytochrome C oxidase subunit 1 gene of nematodes and the V3 hypervariable region of the bacterial 16 s ribosomal RNA gene. We anticipate widespread use of these technologies for diagnostics, species identification and basic research. PMID:22879378
Reliable high-power injection locked 6kHz 60W laser for ArF immersion lithography
NASA Astrophysics Data System (ADS)
Watanabe, Hidenori; Komae, Shigeo; Tanaka, Satoshi; Nohdomi, Ryoichi; Yamazaki, Taku; Nakarai, Hiroaki; Fujimoto, Junichi; Matsunaga, Takashi; Saito, Takashi; Kakizaki, Kouji; Mizoguchi, Hakaru
2007-03-01
Reliable high power 193nm ArF light source is desired for the successive growth of ArF-immersion technology for 45nm node generation. In 2006, Gigaphoton released GT60A, high power injection locked 6kHz/60W/0.5pm (E95) laser system, to meet the demands of semiconductor markets. In this paper, we report key technologies for reliable mass production GT laser systems and GT60A high durability performance test results up to 20 billion pulses.
Engineering of Semiconductor Nanocrystals for Light Emitting Applications
Todescato, Francesco; Fortunati, Ilaria; Minotto, Alessandro; Signorini, Raffaella; Jasieniak, Jacek J.; Bozio, Renato
2016-01-01
Semiconductor nanocrystals are rapidly spreading into the display and lighting markets. Compared with liquid crystal and organic LED displays, nanocrystalline quantum dots (QDs) provide highly saturated colors, wide color gamut, resolution, rapid response time, optical efficiency, durability and low cost. This remarkable progress has been made possible by the rapid advances in the synthesis of colloidal QDs and by the progress in understanding the intriguing new physics exhibited by these nanoparticles. In this review, we provide support to the idea that suitably engineered core/graded-shell QDs exhibit exceptionally favorable optical properties, photoluminescence and optical gain, while keeping the synthesis facile and producing QDs well suited for light emitting applications. Solid-state laser emitters can greatly profit from QDs as efficient gain materials. Progress towards fabricating low threshold, solution processed DFB lasers that are optically pumped using one- and two-photon absorption is reviewed. In the field of display technologies, the exploitation of the exceptional photoluminescence properties of QDs for LCD backlighting has already advanced to commercial levels. The next big challenge is to develop the electroluminescence properties of QD to a similar state. We present an overview of QLED devices and of the great perspectives for next generation display and lighting technologies. PMID:28773794
Recent developments in white light emitting diodes
NASA Astrophysics Data System (ADS)
Lohe, P. P.; Nandanwar, D. V.; Belsare, P. D.; Moharil, S. V.
2018-05-01
In the recent years solid state lighting based on LEDs has revolutionized lighting technology. LEDs have many advantages over the conventional lighting based on fluorescent and incandescent lamps such as mercury free, high conversion efficiency of electrical energy into light, long lifetime reliability and ability to use with many types of devices. LEDs have emerged as a new potentially revolutionary technology that could save up to half of energy used for lighting applications. White LEDs would be the most important light source in the future, so much so that this aspect had been highlighted by the Nobel committee during the award of 2014 Nobel Prize for Physics. Recent advancement in the fabrication of GaN chip capable of emitting in blue and near UV region paved way for fabrication of white LED lamps. Mainly there are two approaches used for preparing white emitting solid state lamp. In the first approach blue light (λ=450 nm) emitted from the InGaN LED chip is partially absorbed by the YAG:Ce3+ phosphor coated on it and re-emitted as yellow fluorescence. A white light can be generated by the combination of blue + yellow emission bands. These lamps are already available. But they are suffering from major drawback that their Colour Rendering Index (CRI) is low. In the second approach, white LEDs are made by coating near ultraviolet emitting (360 to 410nm) LED with a mixture of high efficiency red, green and blue emitting phosphors, analogous to the fluorescent lamp. This method yields lamps with better color rendition. Addition of a yellow emitting phosphor improves CRI further. However conversion efficiency is compromised to some extent. Further the cost of near UV emitting chip is very high compared to blue emitting chips. Thus cost and light output wise, near UV chips are much inferior to blue chips. Recently some rare earth activated oxynitrides, silicates, fluorides have emerged as an important family of luminescent materials for white LED application because they can emit visible light strongly under blue light irradiation. These are chemically, thermally and mechanically stable materials with high efficiency to down convert blue radiation into green and red. Efficient white light can be generated by coating these phosphors on blue LED.CRI of white emitting LED lamp can be improved significantly if green and red emitting phosphors are coated on efficient blue emitting LED chips. In this approach CRI will be maintained if appropriate combination of red, green along with blue emission is used. This article reviews some recent developments in phosphors for white light emitting diodes.
An infrared-driven flexible pyroelectric generator for non-contact energy harvester
NASA Astrophysics Data System (ADS)
Zhao, Tingting; Jiang, Weitao; Liu, Hongzhong; Niu, Dong; Li, Xin; Liu, Weihua; Li, Xuan; Chen, Bangdao; Shi, Yongsheng; Yin, Lei; Lu, Bingheng
2016-04-01
In recent years, energy harvesting technologies, which can scavenge many kinds of energies from our living environment to power micro/nanodevices, have attracted increasing attention. However, remote energy transmission, flexibility and electric waveform controllability remain the key challenges for wireless power supply by an energy harvester. In this paper, we design a new infrared-driven non-contact pyroelectric generator for harvesting heat energy, which avoids direct contact between the pyroelectric generator and heat source and realizes remote energy transfer exploiting the photothermal and penetrability of infrared light. The output voltage (under the input impedance of 100 MOhm) and short-circuit current of the pyroelectric generator consisting of a CNT/PVDF/CNT layer (20 mm × 5 mm × 100 μm) can be as large as 1.2 V and 9 nA, respectively, under a 1.45 W cm-2 near-infrared laser (808 nm). We also demonstrate the means by which the pyroelectric generator can modulate square waveforms with controllable periods through irradiation frequency, which is essential for signal sources and medical stimulators. The overshoot of square waveforms are in a range of 9.0%-13.1% with a rise time of 120 ms. The prepared pyroelectric generator can light a liquid crystal display (LCD) in a vacuum chamber from outside. This work paves the way for non-contact energy harvesting for some particular occasions where near-field energy control is not available.In recent years, energy harvesting technologies, which can scavenge many kinds of energies from our living environment to power micro/nanodevices, have attracted increasing attention. However, remote energy transmission, flexibility and electric waveform controllability remain the key challenges for wireless power supply by an energy harvester. In this paper, we design a new infrared-driven non-contact pyroelectric generator for harvesting heat energy, which avoids direct contact between the pyroelectric generator and heat source and realizes remote energy transfer exploiting the photothermal and penetrability of infrared light. The output voltage (under the input impedance of 100 MOhm) and short-circuit current of the pyroelectric generator consisting of a CNT/PVDF/CNT layer (20 mm × 5 mm × 100 μm) can be as large as 1.2 V and 9 nA, respectively, under a 1.45 W cm-2 near-infrared laser (808 nm). We also demonstrate the means by which the pyroelectric generator can modulate square waveforms with controllable periods through irradiation frequency, which is essential for signal sources and medical stimulators. The overshoot of square waveforms are in a range of 9.0%-13.1% with a rise time of 120 ms. The prepared pyroelectric generator can light a liquid crystal display (LCD) in a vacuum chamber from outside. This work paves the way for non-contact energy harvesting for some particular occasions where near-field energy control is not available. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr09290f
Engineering photonic and plasmonic light emission enhancement
NASA Astrophysics Data System (ADS)
Lawrence, Nathaniel
Semiconductor photonic devices are a rapidly maturing technology which currently occupy multi-billion dollar markets in the areas of LED lighting and optical data communication. LEDs currently demonstrate the highest luminous efficiency of any light source for general lighting. Long-haul optical data communication currently forms the backbone of the global communication network. Proper design of light management is required for photonic devices, which can increase the overall efficiency or add new device functionality. In this thesis, novel methods for the control of light propagation and confinement are developed for the use in integrated photonic devices. The first part of this work focuses on the engineering of field confinement within deep subwavelength plasmonic resonators for the enhancement of light-matter interaction. In this section, plasmonic ring nanocavities are shown to form gap plasmon modes confined to the dielectric region between two metal layers. The scattering properties, near-field enhancement and photonic density of states of nanocavity devices are studied using analytic theory and 3D finite difference time domain simulations. Plasmonic ring nanocavities are fabricated and characterized using photoluminescence intensity and decay rate measurements. A 25 times increase in the radiative decay rate of Er:Si02 is demonstrated in nanocavities where light is confined to volumes as small as 0.01( ln )3. The potential to achieve lasing, due to the enhancement of stimulated emission rate in ring nanocavities, is studied as a route to Si-compatible plasmon-enhanced nanolasers. The second part of this work focuses on the manipulation of light generated in planar semiconductor devices using arrays of dielectric nanopillars. In particular, aperiodic arrays of nanopillars are engineered for omnidirectional light extraction enhancement. Arrays of Er:SiNx, nanopillars are fabricated and a ten times increase in light extraction is experimentally demonstrated, while simultaneously controlling far-field radiation patterns in ways not possible with periodic arrays. Additionally, analytical scalar diffraction theory is used to study light propagation from Vogel spiral arrays and demonstrate generation of OAM. Using phase shifting interferometry, the presence of OAM is experimentally verified. The use of Vogel spirals presents a new method for the generation of OAM with applications for secure optical communications.
Pointer, William David; Baglietto, Emilio
2016-05-01
Here, in the effort to reinvigorate innovation in the way we design, build, and operate the nuclear power generating stations of today and tomorrow, nothing can be taken for granted. Not even the seemingly familiar physics of boiling water. The Consortium for the Advanced Simulation of Light Water Reactors, or CASL, is focused on the deployment of advanced modeling and simulation capabilities to enable the nuclear industry to reduce uncertainties in the prediction of multi-physics phenomena and continue to improve the performance of today’s Light Water Reactors and their fuel. An important part of the CASL mission is the developmentmore » of a next generation thermal hydraulics simulation capability, integrating the history of engineering models based on experimental experience with the computing technology of the future.« less
Fantino, Erika; Chiappone, Annalisa; Roppolo, Ignazio; Manfredi, Diego; Bongiovanni, Roberta; Pirri, Candido Fabrizio; Calignano, Flaviana
2016-05-01
On page 3712, E. Fantino, A. Chiappone, and co-workers fabricate conductive 3D hybrid structures by coupling the photo-reduction of metal precursors with 3D printing technology. The generated structures consist of metal nanoparticles embedded in a polymer matrix shaped into complex multilayered architectures. 3D conductive structures are fabricated with a digital light-processing printer incorporating silver salt into photocurable formulations. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Active implant for optoacoustic natural sound enhancement
NASA Astrophysics Data System (ADS)
Mohrdiek, S.; Fretz, M.; Jose James, R.; Spinola Durante, G.; Burch, T.; Kral, A.; Rettenmaier, A.; Milani, R.; Putkonen, M.; Noell, W.; Ortsiefer, M.; Daly, A.; Vinciguerra, V.; Garnham, C.; Shah, D.
2017-02-01
This paper summarizes the results of an EU project called ACTION: ACTive Implant for Optoacoustic Natural sound enhancement. The project is based on a recent discovery that relatively low levels of pulsed infrared laser light are capable of triggering activity in hair cells of the partially hearing (hearing impaired) cochlea and vestibule. The aim here is the development of a self-contained, smart, highly miniaturized system to provide optoacoustic stimuli directly from an array of miniature light sources in the cochlea. Optoacoustic compound action potentials (oaCAP) are generated by the light source fully inserted into the unmodified cochlea. Previously, the same could only be achieved with external light sources connected to a fiber optic light guide. This feat is achieved by integrating custom made VCSEL arrays at a wavelength of about 1550 nm onto small flexible substrates. The laser light is collimated by a specially designed silicon-based ultra-thin lens (165 um thick) to get the energy density required for the generation of oaCAP signals. A dramatic miniaturization of the packaging technology is also required. A long term biocompatible and hermetic sapphire housing with a size of less than a 1 cubic millimeter and miniature Pt/PtIr feedthroughs is developed, using a low temperature laser assisted process for sealing. A biofouling thin film protection layer is developed to avoid fibrinogen and cell growth on the system.
ChR2 transgenic animals in peripheral sensory system: Sensing light as various sensations.
Ji, Zhi-Gang; Wang, Hongxia
2016-04-01
Since the introduction of Channelrhodopsin-2 (ChR2) to neuroscience, optogenetics technology was developed, making it possible to activate specific neurons or circuits with spatial and temporal precision. Various ChR2 transgenic animal models have been generated and are playing important roles in revealing the mechanisms of neural activities, mapping neural circuits, controlling the behaviors of animals as well as exploring new strategy for treating the neurological diseases in both central and peripheral nervous system. An animal including humans senses environments through Aristotle's five senses (sight, hearing, smell, taste and touch). Usually, each sense is associated with a kind of sensory organ (eyes, ears, nose, tongue and skin). Is it possible that one could hear light, smell light, taste light and touch light? When ChR2 is targeted to different peripheral sensory neurons by viral vectors or generating ChR2 transgenic animals, the animals can sense the light as various sensations such as hearing, touch, pain, smell and taste. In this review, we focus on ChR2 transgenic animals in the peripheral nervous system. Firstly the working principle of ChR2 as an optogenetic actuator is simply described. Then the current transgenic animal lines where ChR2 was expressed in peripheral sensory neurons are presented and the findings obtained by these animal models are reviewed. Copyright © 2016 Elsevier Inc. All rights reserved.
Rotation State Evolution of Retired Geosynchronous Satellites
NASA Astrophysics Data System (ADS)
Benson, C.; Scheeres, D. J.; Ryan, W. H.; Ryan, E. V.; Moskovitz, N.
Non-periodic light curve rotation state analysis is conducted for the retired geosynchronous satellite GOES 8. This particular satellite has been observed periodically at the Maui Research and Technology Center as well as Magdalena Ridge and Lowell Observatories since 2013. To extract tumbling periods from the light curves, twodimensional Fourier series fits were used. Torque-free dynamics and the satellite’s known mass properties were then leveraged to constrain the candidate periods. Finally, simulated light curves were generated using a representative shape model for further validation. Analysis of the light curves suggests that GOES 8 transitioned from uniform rotation in 2014 to continually evolving tumbling motion by 2016. These findings are consistent with previous dynamical simulations and support the hypothesis that the Yarkovsky-O’Keefe-Radzievskii-Paddack (YORP) effect drives rotation state evolution of retired geosynchronous satellites.
A Simple Demonstration for Exploring the Radio Waves Generated by a Mobile Phone
ERIC Educational Resources Information Center
Hare, Jonathan
2010-01-01
Described is a simple low cost home-made device that converts the radio wave energy from a mobile phone signal into electricity for lighting an LED. No battery or complex circuitry is required. The device can form the basis of a range of interesting experiments on the physics and technology of mobile phones. (Contains 5 figures.)
Recent developments in luminescent solar concentrators
NASA Astrophysics Data System (ADS)
van Sark, W. G. J. H. M.
2014-10-01
High efficiency photovoltaic devices combine full solar spectrum absorption and effective generation and collection of charge carriers, while commercial success depends on cost effectiveness in manufacturing. Spectrum modification using down shifting has been demonstrated in luminescent solar concentrators (LSCs) since the 1970s, as a cheap alternative for standard c-Si technology. LSCs consist of a highly transparent plastic plate, in which luminescent species are dispersed, which absorb incident light and emit light at a red-shifted wavelength, with high quantum efficiency. Material issues have hampered efficiency improvements, in particular re-absorption of light emitted by luminescent species and stability of these species. In this contribution, approaches are reviewed on minimizing re-absorption, which should allow surpassing the 10% luminescent solar concentrator efficiency barrier.
ERIC Educational Resources Information Center
Maniccia, Dorine
2003-01-01
Explains that by using sustainable (green) building practices, schools and universities can make their lighting systems more efficient, noting that embracing green design principles can help schools attract students. Discusses lighting-control technologies (occupancy sensing technology, daylighting technology, and scheduling based technologies),…
Production of Biogas from wastes Blended with CowDung for Electricity generation-A Case study
NASA Astrophysics Data System (ADS)
Muthu, D.; Venkatasubramanian, C.; Ramakrishnan, K.; Sasidhar, Jaladanki
2017-07-01
The country’s production of solid waste generation is piling up year after year and the generation of Bio-Gas finds a fruitful solution to overcome this problem. This technology can contribute to energy conservation if the economic viability and social acceptance of this technology are favorable. Our campus has a number of hostel buildings which generates large quantum of kitchen waste and sewage per day. This research will have process ofcarrying out survey, characterization of kitchen waste from several kitchens & Canteens and knowing the potential for biogas production. The waste generated from kitchen and sewage from the hostels is given as feedstock to produce 600 m3 of biogas per day with cow dung as byproduct. The methane gas generated from Biogas is purified and this is used for power generation. Two biogas engine generators of 30 kVA and 50 kVA were installed. This power is used for backup power for girl’s hostel lighting load. From this study it is concluded that the generation of Biogas production and its usage for power production is the best option to handle these large quantum of sewage, kitchen waste generated from various buildings and also treated effluent from biogas plant and the biomass generated is a wealth for doing agriculture for any community ultimately it protects the environment.
The Performance Analysis of AN Indoor Mobile Mapping System with Rgb-D Sensor
NASA Astrophysics Data System (ADS)
Tsai, G. J.; Chiang, K. W.; Chu, C. H.; Chen, Y. L.; El-Sheimy, N.; Habib, A.
2015-08-01
Over the years, Mobile Mapping Systems (MMSs) have been widely applied to urban mapping, path management and monitoring and cyber city, etc. The key concept of mobile mapping is based on positioning technology and photogrammetry. In order to achieve the integration, multi-sensor integrated mapping technology has clearly established. In recent years, the robotic technology has been rapidly developed. The other mapping technology that is on the basis of low-cost sensor has generally used in robotic system, it is known as the Simultaneous Localization and Mapping (SLAM). The objective of this study is developed a prototype of indoor MMS for mobile mapping applications, especially to reduce the costs and enhance the efficiency of data collection and validation of direct georeferenced (DG) performance. The proposed indoor MMS is composed of a tactical grade Inertial Measurement Unit (IMU), the Kinect RGB-D sensor and light detection, ranging (LIDAR) and robot. In summary, this paper designs the payload for indoor MMS to generate the floor plan. In first session, it concentrates on comparing the different positioning algorithms in the indoor environment. Next, the indoor plans are generated by two sensors, Kinect RGB-D sensor LIDAR on robot. Moreover, the generated floor plan will compare with the known plan for both validation and verification.
Superconducting light generator for large offshore wind turbines
NASA Astrophysics Data System (ADS)
Sanz, S.; Arlaban, T.; Manzanas, R.; Tropeano, M.; Funke, R.; Kováč, P.; Yang, Y.; Neumann, H.; Mondesert, B.
2014-05-01
Offshore wind market demands higher power rate and reliable turbines in order to optimize capital and operational cost. These requests are difficult to overcome with conventional generator technologies due to a significant weight and cost increase with the scaling up. Thus superconducting materials appears as a prominent solution for wind generators, based on their capacity to held high current densities with very small losses, which permits to efficiently replace copper conductors mainly in the rotor field coils. However the state-of-the-art superconducting generator concepts still seem to be expensive and technically challenging for the marine environment. This paper describes a 10 MW class novel direct drive superconducting generator, based on MgB2 wires and a modular cryogen free cooling system, which has been specifically designed for the offshore wind industry needs.
Development of a near-infrared spectroscopy instrument for applications in urology.
Macnab, Andrew J; Stothers, Lynn
2008-10-01
Near infrared spectroscopy (NIRS) is an established technology using photons of light in the near infrared spectrum to monitor changes in tissue of naturally occurring chromophores, including oxygenated and deoxygenated hemoglobin. Technology and methodology have been validated for measurement of a range of physiologic parameters. NIRS has been applied successfully in urology research; however current instruments are designed principally for brain and muscle study. To describe development of a NIRS instrument specifically designed for monitoring changes in chromophore concentration in the bladder detrusor in real time, to facilitate research to establish the role of this non-invasive technology in the evaluation of patients with voiding dysfunction The portable continuous wave NIRS instrument has a 3 laser diode light source (785, 808 and 830 nanometers), fiber optic cables for light transmission, a self adhesive patient interface patch with an emitter and sensor, and software to detect the difference between the light transmitted and received by the instrument. Software incorporated auto-attenuates the optical signals and converts raw optical data into chromophore concentrations displayed graphically. The prototype was designed, tested, and iteratively developed to achieve optimal suprapubic transcutaneous monitoring of the detrusor in human subjects during bladder filling and emptying. Evaluation with simultaneous invasive urodynamic measurement in men and women indicates good specificity and sensitivity of NIRS chromophore concentration changes by receiver operator curve analysis, and correlation between NIRS data and urodynamic pressures. Urological monitoring with this NIRS instrument is feasible and generates data of potential diagnostic value.
NASA-UVA Light Aerospace Alloy and Structures Technology Program (LA2ST)
NASA Technical Reports Server (NTRS)
Gangloff, Richard P.; Scully, John R.; Stoner, Glenn E.; Thornton, Earl A.; Wawner, Franklin E., Jr.; Wert, John A.
1993-01-01
The NASA-UVA Light Aerospace Alloy and Structures Technology (LA2ST) Program continues a high level of activity. Progress achieved between 1 Jan. and 30 Jun. 1993 is reported. The objective of the LA2ST Program is to conduct interdisciplinary graduate student research on the performance of next generation, light weight aerospace alloys, composites, and thermal gradient structures in collaboration with NASA-Langley researchers. The following projects are addressed: environmental fatigue of Al-Li-Cu alloys; mechanisms of localized corrosion and environmental fracture in Al-Cu-Li-Mg-Ag alloy X2095 and compositional variations; the effect of zinc additions on the precipitation and stress corrosion cracking behavior of alloy 8090; hydrogen interactions with Al-Li-Cu alloy 2090 and model alloys; metastable pitting of aluminum alloys; cryogenic fracture toughness of Al-Cu-Li + In alloys; the fracture toughness of Weldalite (TM); elevated temperature cracking of advanced I/M aluminum alloys; response of Ti-1100/SCS-6 composites to thermal exposure; superplastic forming of Weldalite (TM); research to incorporate environmental effects into fracture mechanics fatigue life prediction codes such as NASA FLAGRO; and thermoviscoplastic behavior.
Synthetic Vision Systems - Operational Considerations Simulation Experiment
NASA Technical Reports Server (NTRS)
Kramer, Lynda J.; Williams, Steven P.; Bailey, Randall E.; Glaab, Louis J.
2007-01-01
Synthetic vision is a computer-generated image of the external scene topography that is generated from aircraft attitude, high-precision navigation information, and data of the terrain, obstacles, cultural features, and other required flight information. A synthetic vision system (SVS) enhances this basic functionality with real-time integrity to ensure the validity of the databases, perform obstacle detection and independent navigation accuracy verification, and provide traffic surveillance. Over the last five years, NASA and its industry partners have developed and deployed SVS technologies for commercial, business, and general aviation aircraft which have been shown to provide significant improvements in terrain awareness and reductions in the potential for Controlled-Flight-Into-Terrain incidents/accidents compared to current generation cockpit technologies. It has been hypothesized that SVS displays can greatly improve the safety and operational flexibility of flight in Instrument Meteorological Conditions (IMC) to a level comparable to clear-day Visual Meteorological Conditions (VMC), regardless of actual weather conditions or time of day. An experiment was conducted to evaluate SVS and SVS-related technologies as well as the influence of where the information is provided to the pilot (e.g., on a Head-Up or Head-Down Display) for consideration in defining landing minima based upon aircraft and airport equipage. The "operational considerations" evaluated under this effort included reduced visibility, decision altitudes, and airport equipage requirements, such as approach lighting systems, for SVS-equipped aircraft. Subjective results from the present study suggest that synthetic vision imagery on both head-up and head-down displays may offer benefits in situation awareness; workload; and approach and landing performance in the visibility levels, approach lighting systems, and decision altitudes tested.
Synthetic vision systems: operational considerations simulation experiment
NASA Astrophysics Data System (ADS)
Kramer, Lynda J.; Williams, Steven P.; Bailey, Randall E.; Glaab, Louis J.
2007-04-01
Synthetic vision is a computer-generated image of the external scene topography that is generated from aircraft attitude, high-precision navigation information, and data of the terrain, obstacles, cultural features, and other required flight information. A synthetic vision system (SVS) enhances this basic functionality with real-time integrity to ensure the validity of the databases, perform obstacle detection and independent navigation accuracy verification, and provide traffic surveillance. Over the last five years, NASA and its industry partners have developed and deployed SVS technologies for commercial, business, and general aviation aircraft which have been shown to provide significant improvements in terrain awareness and reductions in the potential for Controlled-Flight-Into-Terrain incidents / accidents compared to current generation cockpit technologies. It has been hypothesized that SVS displays can greatly improve the safety and operational flexibility of flight in Instrument Meteorological Conditions (IMC) to a level comparable to clear-day Visual Meteorological Conditions (VMC), regardless of actual weather conditions or time of day. An experiment was conducted to evaluate SVS and SVS-related technologies as well as the influence of where the information is provided to the pilot (e.g., on a Head-Up or Head-Down Display) for consideration in defining landing minima based upon aircraft and airport equipage. The "operational considerations" evaluated under this effort included reduced visibility, decision altitudes, and airport equipage requirements, such as approach lighting systems, for SVS-equipped aircraft. Subjective results from the present study suggest that synthetic vision imagery on both head-up and head-down displays may offer benefits in situation awareness; workload; and approach and landing performance in the visibility levels, approach lighting systems, and decision altitudes tested.
Light field imaging and application analysis in THz
NASA Astrophysics Data System (ADS)
Zhang, Hongfei; Su, Bo; He, Jingsuo; Zhang, Cong; Wu, Yaxiong; Zhang, Shengbo; Zhang, Cunlin
2018-01-01
The light field includes the direction information and location information. Light field imaging can capture the whole light field by single exposure. The four-dimensional light field function model represented by two-plane parameter, which is proposed by Levoy, is adopted in the light field. Acquisition of light field is based on the microlens array, camera array and the mask. We calculate the dates of light-field to synthetize light field image. The processing techniques of light field data include technology of refocusing rendering, technology of synthetic aperture and technology of microscopic imaging. Introducing the technology of light field imaging into THz, the efficiency of 3D imaging is higher than that of conventional THz 3D imaging technology. The advantages compared with visible light field imaging include large depth of field, wide dynamic range and true three-dimensional. It has broad application prospects.
Computational design of materials for solar hydrogen generation
NASA Astrophysics Data System (ADS)
Umezawa, Naoto
Photocatalysis has a great potential for the production of hydrogen from aquerous solution under solar light. In this talk, two different approaches toward the computational materials desing for solar hydrogen generation will be presented. Tin (Sn), which has two major oxidation states, Sn2+ and Sn4+, is abundant on the earth's crust. Recently, visible-light responsive photocatalytc H2 evolution reaction was identified over a mixed valence tin oxide Sn3O4. We have carried out crystal structure prediction for mixed valence tin oxides in different atomic compositions under ambient pressure condition using advanced computational methods based on the evolutionary crystal-structure search and density-functional theory. The predicted novel crystal structures realize the desirable band gaps and band edge positions for H2 evolution under visible light irradiation. It is concluded that multivalent tin oxides have a great potential as an abundant, cheap and environmentally-benign solar-energy conversion photofunctional materials. Transition metal doping is effective for sensitizing SrTiO3 under visible light. We have theoretically investigated the roles of the doped Cr in STO based on hybrid density-functional calculations. Cr atoms are preferably substituting for Ti under any equilibrium growth conditions. The lower oxidation state Cr3+, which is stabilized under an n-type condition of STO, is found to be advantageous for the photocatalytic performance. It is firther predicted that lanthanum is the best codopant for stabilizing the favorable oxidation state, Cr3+. The prediction was validated by our experiments that La and Cr co-doped STO shows the best performance among examined samples. This work was supported by the Japan Science and Technology Agency (JST) Precursory Research for Embryonic Science and Technology (PRESTO) and International Research Fellow program of Japan Society for the Promotion of Science (JSPS) through project P14207.
Massive MIMO-OFDM indoor visible light communication system downlink architecture design
NASA Astrophysics Data System (ADS)
Lang, Tian; Li, Zening; Chen, Gang
2014-10-01
Multiple-input multiple-output (MIMO) technique is now used in most new broadband communication system, and orthogonal frequency division multiplexing (OFDM) is also utilized within current 4th generation (4G) of mobile telecommunication technology. With MIMO and OFDM combined, visible light communication (VLC) system's diversity gain is increase, yet system capacity for dispersive channels is also enhanced. Moreover, with the emerging massive MIMO-OFDM VLC system, there are significant advantages than smaller systems' such as channel hardening, further increasing of energy efficiency (EE) and spectral efficiency (SE) based on law of large number. This paper addresses one of the major technological challenges, system architecture design, which was solved by semispherical beehive structure (SBS) receiver and so that diversity gain can be identified and applied in Massive MIMO VLC system. Simulation results shows that the proposed design clearly presents a spatial diversity over conventional VLC systems.
Efficient conceptual design for LED-based pixel light vehicle headlamps
NASA Astrophysics Data System (ADS)
Held, Marcel Philipp; Lachmayer, Roland
2017-12-01
High-resolution vehicle headlamps represent a future-oriented technology that can be used to increase traffic safety and driving comfort. As a further development to the current Matrix Beam headlamps, LED-based pixel light systems enable ideal lighting functions (e.g. projection of navigation information onto the road) to be activated in any given driving scenario. Moreover, compared to other light-modulating elements such as DMDs and LCDs, instantaneous LED on-off toggling provides a decisive advantage in efficiency. To generate highly individualized light distributions for automotive applications, a number of approaches using an LED array may be pursued. One approach is to vary the LED density in the array so as to output the desired light distribution. Another notable approach makes use of an equidistant arrangement of the individual LEDs together with distortion optics to formulate the desired light distribution. The optical system adjusts the light distribution in a manner that improves resolution and increases luminous intensity of the desired area. An efficient setup for pixel generation calls for one lens per LED. Taking into consideration the limited space requirements of the system, this implies that the luminous flux, efficiency and resolution image parameters are primarily controlled by the lens dimensions. In this paper a concept for an equidistant LED array arrangement utilizing distortion optics is presented. The paper is divided into two parts. The first part discusses the influence of lens geometry on the system efficiency whereas the second part investigates the correlation between resolution and luminous flux based on the lens dimensions.
Compact 2100 nm laser diode module for next-generation DIRCM
NASA Astrophysics Data System (ADS)
Dvinelis, Edgaras; Greibus, Mindaugas; TrinkÅ«nas, Augustinas; NaujokaitÄ--, Greta; Vizbaras, Augustinas; Vizbaras, Dominykas; Vizbaras, Kristijonas
2017-10-01
Compact high-power 2100 nm laser diode module for next-generation directional infrared countermeasure (DIRCM) systems is presented. Next-generation DIRCM systems require compact, light-weight and robust laser modules which could provide intense IR light emission capable of disrupting the tracking sensor of heat-seeking missile. Currently used solid-state and fiber laser solutions for mid-IR band are bulky and heavy making them difficult to implement in smaller form-factor DIRCM systems. Recent development of GaSb laser diode technology greatly improved optical output powers and efficiencies of laser diodes working in 1900 - 2450 nm band [1] while also maintaining very attractive size, weight, power consumption and cost characteristics. 2100 nm laser diode module presented in this work performance is based on high-efficiency broad emitting area GaSb laser diode technology. Each laser diode emitter is able to provide 1 W of CW output optical power with working point efficiency up to 20% at temperature of 20 °C. For output beam collimation custom designed fast-axis collimator and slow-axis collimator lenses were used. These lenses were actively aligned and attached using UV epoxy curing. Total 2 emitters stacked vertically were used in 2100 nm laser diode module. Final optical output power of the module goes up to 2 W at temperature of 20 °C. Total dimensions of the laser diode module are 35 x 25 x 16 mm (L x W x H) with a weight of 28 grams. Finally output beam is bore-sighted to mechanical axes of the module housing allowing for easy integration into next-generation DIRCM systems.
Using the ISS as a testbed to prepare for the next generation of space-based telescopes
NASA Astrophysics Data System (ADS)
Postman, Marc; Sparks, William B.; Liu, Fengchuan; Ess, Kim; Green, Joseph; Carpenter, Kenneth G.; Thronson, Harley; Goullioud, Renaud
2012-09-01
The infrastructure available on the ISS provides a unique opportunity to develop the technologies necessary to assemble large space telescopes. Assembling telescopes in space is a game-changing approach to space astronomy. Using the ISS as a testbed enables a concentration of resources on reducing the technical risks associated with integrating the technologies, such as laser metrology and wavefront sensing and control (WFS&C), with the robotic assembly of major components including very light-weight primary and secondary mirrors and the alignment of the optical elements to a diffraction-limited optical system in space. The capability to assemble the optical system and remove and replace components via the existing ISS robotic systems such as the Special Purpose Dexterous Manipulator (SPDM), or by the ISS Flight Crew, allows for future experimentation as well as repair if necessary. In 2015, first light will be obtained by the Optical Testbed and Integration on ISS eXperiment (OpTIIX), a small 1.5-meter optical telescope assembled on the ISS. The primary objectives of OpTIIX include demonstrating telescope assembly technologies and end-to-end optical system technologies that will advance future large optical telescopes.
Integrated process modeling for the laser inertial fusion energy (LIFE) generation system
NASA Astrophysics Data System (ADS)
Meier, W. R.; Anklam, T. M.; Erlandson, A. C.; Miles, R. R.; Simon, A. J.; Sawicki, R.; Storm, E.
2010-08-01
A concept for a new fusion-fission hybrid technology is being developed at Lawrence Livermore National Laboratory. The primary application of this technology is base-load electrical power generation. However, variants of the baseline technology can be used to "burn" spent nuclear fuel from light water reactors or to perform selective transmutation of problematic fission products. The use of a fusion driver allows very high burn-up of the fission fuel, limited only by the radiation resistance of the fuel form and system structures. As a part of this process, integrated process models have been developed to aid in concept definition. Several models have been developed. A cost scaling model allows quick assessment of design changes or technology improvements on cost of electricity. System design models are being used to better understand system interactions and to do design trade-off and optimization studies. Here we describe the different systems models and present systems analysis results. Different market entry strategies are discussed along with potential benefits to US energy security and nuclear waste disposal. Advanced technology options are evaluated and potential benefits from additional R&D targeted at the different options is quantified.
Horlick-Jones, Tom; Prades, Ana; Espluga, Josep
2012-07-01
The extent to which nuclear energy technologies are, in some sense, "stigmatised" by historical environmental and military associations is of particular interest in contemporary debates about sustainable energy policy. Recent claims in the literature suggest that despite such stigmatisation, lay views on such technologies may be shifting towards a "reluctant acceptance," in the light of concerns about issues like anthropogenic climate change. In this paper, we report on research into learning and reasoning processes concerned with a largely unknown nuclear energy technology; namely fusion power. We focus on the role of the nuclear label, or "brand," in informing how lay citizens make sense of the nature of this technology. Our findings derive from a comparative analysis of data generated in Spain and Britain, using the same methodology.
Discussion on Application of Space Materials and Technological Innovation in Dynamic Fashion Show
NASA Astrophysics Data System (ADS)
Huo, Meilin; Kim, Chul Soo; Zhao, Wenhan
2018-03-01
In modern dynamic fashion show, designers often use the latest ideas and technology, and spend their energy in stage effect and overall environment to make audience’s watching a fashion show like an audio-visual feast. With rapid development of China’s science and technology, it has become a design trend to strengthen the relationship between new ideas, new trends and technology in modern art. With emergence of new technology, new methods and new materials, designers for dynamic fashion show stage art can choose the materials with an increasingly large scope. Generation of new technology has also made designers constantly innovate the stage space design means, and made the stage space design innovated constantly on the original basis of experiences. The dynamic clothing display space is on design of clothing display space, layout, platform decoration style, platform models, performing colors, light arrangement, platform background, etc.
NASA Technical Reports Server (NTRS)
Postman, Marc; Brown, Tom; Sembach, Kenneth; Giavalisco, Mauro; Traub, Wesley; Stapelfeldt, Karl; Calzetti, Daniela; Oegerle, William; Rich, R. Michael; Stahl, H. Phillip;
2011-01-01
The Advanced Technology Large-Aperture Space Telescope (ATLAST) is a concept for an 8-meter to 16-meter UVOIR space observatory for launch in the 2025-2030 era. ATLAST will allow astronomers to answer fundamental questions at the forefront of modern astrophysics, including "Is there life elsewhere in the Galaxy?" We present a range of science drivers and the resulting performance requirements for ATLAST (8 to 16 milliarcsecond angular resolution, diffraction limited imaging at 0.5 m wavelength, minimum collecting area of 45 square meters, high sensitivity to light wavelengths from 0.1 m to 2.4 m, high stability in wavefront sensing and control). We also discuss the priorities for technology development needed to enable the construction of ATLAST for a cost that is comparable to current generation observatory-class space missions. Keywords: Advanced Technology Large-Aperture Space Telescope (ATLAST); ultraviolet/optical space telescopes; astrophysics; astrobiology; technology development.
Electrical and Optical Enhancement in Internally Nanopatterned Organic Light-Emitting Diodes
NASA Astrophysics Data System (ADS)
Fina, Michael Dane
Organic light-emitting diodes (OLEDs) have made tremendous technological progress in the past two decades and have emerged as a top competitor for next generation light-emitting displays and lighting. State-of-the-art OLEDs have been reported in literature to approach, and even surpass, white fluorescent tube efficiency. However, despite rapid technological progress, efficiency metrics must be improved to compete with traditional inorganic light-emitting diode (LED) technology. Organic materials possess specialized traits that permit manipulations to the light-emitting cavity. Overall, as demonstrated within, these modifications can be used to improve electrical and optical device efficiencies. This work is focused at analyzing the effects that nanopatterned geometric modifications to the organic active layers play on device efficiency. In general, OLED efficiency is complicated by the complex, coupled processes which contribute to spontaneous dipole emission. A composite of three sub-systems (electrical, exciton and optical) ultimately dictate the OLED device efficiency. OLED electrical operation is believed to take place via a low-mobility-modified Schottky injection process. In the injection-limited regime, geometric effects are expected to modify the local electric field leading to device current enhancement. It is shown that the patterning effect can be used to enhance charge carrier parity, thereby enhancing overall recombination. Current density and luminance characteristics are shown to be improved by OLED nanopatterning from both the model developed within and experimental techniques. Next, the optical enhancement effects produced by the nanopatterned array are considered. Finite-difference time-domain (FDTD) simulations are used to determine positional, spectral optical enhancement for the nanopatterned device. The results show beneficial effects to the device performance. The optical enhancements are related to the reduction in internal radiative quenching (improved internal quantum efficiency) and improvement in light extraction (improved outcoupling efficiency). Furthermore, the electrical model is used to construct a positional radiative efficiency map that when combined with the optical enhancement reveals the overall external quantum efficiency enhancement.
Developing the Next Generation Shell Buckling Design Factors and Technologies
NASA Technical Reports Server (NTRS)
Hilburger, Mark W.
2012-01-01
NASA s Shell Buckling Knockdown Factor (SBKF) Project was established in the spring of 2007 by the NASA Engineering and Safety Center (NESC) in collaboration with the Constellation Program and Exploration Systems Mission Directorate. The SBKF project has the current goal of developing less-conservative, robust shell buckling design factors (a.k.a. knockdown factors) and design and analysis technologies for light-weight stiffened metallic launch vehicle (LV) structures. Preliminary design studies indicate that implementation of these new knockdown factors can enable significant reductions in mass and mass-growth in these vehicles and can help mitigate some of NASA s LV development and performance risks. In particular, it is expected that the results from this project will help reduce the reliance on testing, provide high-fidelity estimates of structural performance, reliability, robustness, and enable increased payload capability. The SBKF project objectives and approach used to develop and validate new design technologies are presented, and provide a glimpse into the future of design of the next generation of buckling-critical launch vehicle structures.
NASA Astrophysics Data System (ADS)
Frankowski, G.; Hainich, R.
2009-02-01
Since the mid-eighties, a fundamental idea for achieving measuring accuracy in projected fringe technology was to consider the projected fringe pattern as an interferogram and evaluate it on the basis of advanced algorithms widely used for phase measuring in real-time interferometry. A fundamental requirement for obtaining a sufficiently high degree of measuring accuracy with this so-called "phase measuring projected fringe technology" is that the projected fringes, analogous to interference fringes, must have a cos2-shaped intensity distribution. Until the mid-nineties, this requirement for the projected fringe pattern measurement technology presented a basic handicap for its wide application in 3D metrology. This situation changed abruptly, when in the nineties Texas Instruments introduced to the market advanced digital light projection on the basis of micro mirror based projection systems, socalled DLP technology, which also facilitated the generation and projection of cos2-shaped intensity and/or fringe patterns. With this DLP technology, which from its original approach was actually oriented towards completely different applications such as multimedia projection, Texas Instruments boosted phase-measuring fringe projection in optical 3D metrology to a worldwide breakthrough both for medical as well as industrial applications. A subject matter of the lecture will be to present the fundamental principles and the resulting advantages of optical 3D metrology based on phase-measuring fringe projection using DLP technology. Further will be presented and discussed applications of the measurement technology in medical engineering and industrial metrology.
Projecting light beams with 3D waveguide arrays
NASA Astrophysics Data System (ADS)
Crespi, Andrea; Bragheri, Francesca
2017-01-01
Free-space light beams with complex intensity patterns, or non-trivial phase structure, are demanded in diverse fields, ranging from classical and quantum optical communications, to manipulation and imaging of microparticles and cells. Static or dynamic spatial light modulators, acting on the phase or intensity of an incoming light wave, are the conventional choices to produce beams with such non-trivial characteristics. However, interfacing these devices with optical fibers or integrated optical circuits often requires difficult alignment or cumbersome optical setups. Here we explore theoretically and with numerical simulations the potentialities of directly using the output of engineered three-dimensional waveguide arrays, illuminated with linearly polarized light, to project light beams with peculiar structures. We investigate through a collection of illustrative configurations the far field distribution, showing the possibility to achieve orbital angular momentum, or to produce elaborate intensity or phase patterns with several singularity points. We also simulate the propagation of the projected beam, showing the possibility to concentrate light. We note that these devices should be at reach of current technology, thus perspectives are open for the generation of complex free-space optical beams from integrated waveguide circuits.
Doppler Global Velocimetry Measurements for Supersonic Flow Fields
NASA Technical Reports Server (NTRS)
Meyers, James F.
2005-01-01
The application of Doppler Global Velocimetry (DGV) to high-speed flows has its origins in the original development of the technology by Komine et al (1991). Komine used a small shop-air driven nozzle to generate a 200 m/s flow. This flow velocity was chosen since it produced a fairly large Doppler shift in the scattered light, resulting in a significant transmission loss as the light passed through the Iodine vapor. This proof-of-concept investigation showed that the technology was capable of measuring flow velocity within a measurement plane defined by a single-frequency laser light sheet. The effort also proved that velocity measurements could be made without resolving individual seed particles as required by other techniques such as Fringe- Type Laser Velocimetry and Particle Image Velocimetry. The promise of making planar velocity measurements with the possibility of using 0.1-micron condensation particles for seeding, Dibble et al (1989), resulted in the investigation of supersonic jet flow fields, Elliott et al (1993) and Smith and Northam (1995) - Mach 2.0 and 1.9 respectively. Meyers (1993) conducted a wind tunnel investigation above an inclined flat plate at Mach 2.5 and above a delta wing at Mach 2.8 and 4.6. Although these measurements were crude from an accuracy viewpoint, they did prove that the technology could be used to study supersonic flows using condensation as the scattering medium. Since then several research groups have studied the technology and developed solutions and methodologies to overcome most of the measurement accuracy limitations:
On the Properties and Design of Organic Light-Emitting Devices
NASA Astrophysics Data System (ADS)
Erickson, Nicholas C.
Organic light-emitting devices (OLEDs) are attractive for use in next-generation display and lighting technologies. In display applications, OLEDs offer a wide emission color gamut, compatibility with flexible substrates, and high power efficiencies. In lighting applications, OLEDs offer attractive features such as broadband emission, high-performance, and potential compatibility with low-cost manufacturing methods. Despite recent demonstrations of near unity internal quantum efficiencies (photons out per electron in), OLED adoption lags conventional technologies, particularly in large-area displays and general lighting applications. This thesis seeks to understand the optical and electronic properties of OLED materials and device architectures which lead to not only high peak efficiency, but also reduced device complexity, high efficiency under high excitation, and optimal white-light emission. This is accomplished through the careful manipulation of organic thin film compositions fabricated via vacuum thermal evaporation, and the introduction of a novel device architecture, the graded-emissive layer (G-EML). This device architecture offers a unique platform to study the electronic properties of varying compositions of organic semiconductors and the resulting device performance. This thesis also introduces an experimental technique to measure the spatial overlap of electrons and holes within an OLED's emissive layer. This overlap is an important parameter which is affected by the choice of materials and device design, and greatly impacts the operation of the OLED at high excitation densities. Using the G-EML device architecture, OLEDs with improved efficiency characteristics are demonstrated, achieving simultaneously high brightness and high efficiency.
Replacement policy of residential lighting optimized for cost, energy, and greenhouse gas emissions
NASA Astrophysics Data System (ADS)
Liu, Lixi; Keoleian, Gregory A.; Saitou, Kazuhiro
2017-11-01
Accounting for 10% of the electricity consumption in the US, artificial lighting represents one of the easiest ways to cut household energy bills and greenhouse gas (GHG) emissions by upgrading to energy-efficient technologies such as compact fluorescent lamps (CFL) and light emitting diodes (LED). However, given the high initial cost and rapidly improving trajectory of solid-state lighting today, estimating the right time to switch over to LEDs from a cost, primary energy, and GHG emissions perspective is not a straightforward problem. This is an optimal replacement problem that depends on many determinants, including how often the lamp is used, the state of the initial lamp, and the trajectories of lighting technology and of electricity generation. In this paper, multiple replacement scenarios of a 60 watt-equivalent A19 lamp are analyzed and for each scenario, a few replacement policies are recommended. For example, at an average use of 3 hr day-1 (US average), it may be optimal both economically and energetically to delay the adoption of LEDs until 2020 with the use of CFLs, whereas purchasing LEDs today may be optimal in terms of GHG emissions. In contrast, incandescent and halogen lamps should be replaced immediately. Based on expected LED improvement, upgrading LED lamps before the end of their rated lifetime may provide cost and environmental savings over time by taking advantage of the higher energy efficiency of newer models.
Impact of multi-focused images on recognition of soft biometric traits
NASA Astrophysics Data System (ADS)
Chiesa, V.; Dugelay, J. L.
2016-09-01
In video surveillance semantic traits estimation as gender and age has always been debated topic because of the uncontrolled environment: while light or pose variations have been largely studied, defocused images are still rarely investigated. Recently the emergence of new technologies, as plenoptic cameras, yields to deal with these problems analyzing multi-focus images. Thanks to a microlens array arranged between the sensor and the main lens, light field cameras are able to record not only the RGB values but also the information related to the direction of light rays: the additional data make possible rendering the image with different focal plane after the acquisition. For our experiments, we use the GUC Light Field Face Database that includes pictures from the First Generation Lytro camera. Taking advantage of light field images, we explore the influence of defocusing on gender recognition and age estimation problems. Evaluations are computed on up-to-date and competitive technologies based on deep learning algorithms. After studying the relationship between focus and gender recognition and focus and age estimation, we compare the results obtained by images defocused by Lytro software with images blurred by more standard filters in order to explore the difference between defocusing and blurring effects. In addition we investigate the impact of deblurring on defocused images with the goal to better understand the different impacts of defocusing and standard blurring on gender and age estimation.
Radioisotope Electric Propulsion for Fast Outer Planetary Orbiters
NASA Technical Reports Server (NTRS)
Oleson, Steven; Benson, Scott; Gefert, Leon; Patterson, Michael; Schreiber, Jeffrey
2002-01-01
Recent interest in outer planetary targets by the Office of Space Science has spurred the search for technology options to enable relatively quick missions to outer planetary targets. Several options are being explored including solar electric propelled stages combined with aerocapture at the target and nuclear electric propulsion. Another option uses radioisotope powered electric thrusters to reach the outer planets. Past work looked at using this technology to provide faster flybys. A better use for this technology is for outer planet orbiters. Combined with medium class launch vehicles and a new direct trajectory these small, sub-kilowatt ion thrusters and Stirling radioisotope generators were found to allow missions as fast as 5 to 12 years for objects from Saturn to Pluto, respectively. Key to the development is light spacecraft and science payload technologies.
Inertial energy storage for advanced space station applications
NASA Technical Reports Server (NTRS)
Van Tassel, K. E.; Simon, W. E.
1985-01-01
Because the NASA Space Station will spend approximately one-third of its orbital time in the earth's shadow, depriving it of solar energy and requiring an energy storage system to meet system demands, attention has been given to flywheel energy storage systems. These systems promise high mechanical efficiency, long life, light weight, flexible design, and easily monitored depth of discharge. An assessment is presently made of three critical technology areas: rotor materials, magnetic suspension bearings, and motor-generators for energy conversion. Conclusions are presented regarding the viability of inertial energy storage systems and of problem areas requiring further technology development efforts.
Mask technology for EUV lithography
NASA Astrophysics Data System (ADS)
Bujak, M.; Burkhart, Scott C.; Cerjan, Charles J.; Kearney, Patrick A.; Moore, Craig E.; Prisbrey, Shon T.; Sweeney, Donald W.; Tong, William M.; Vernon, Stephen P.; Walton, Christopher C.; Warrick, Abbie L.; Weber, Frank J.; Wedowski, Marco; Wilhelmsen, Karl C.; Bokor, Jeffrey; Jeong, Sungho; Cardinale, Gregory F.; Ray-Chaudhuri, Avijit K.; Stivers, Alan R.; Tejnil, Edita; Yan, Pei-yang; Hector, Scott D.; Nguyen, Khanh B.
1999-04-01
Extreme UV Lithography (EUVL) is one of the leading candidates for the next generation lithography, which will decrease critical feature size to below 100 nm within 5 years. EUVL uses 10-14 nm light as envisioned by the EUV Limited Liability Company, a consortium formed by Intel and supported by Motorola and AMD to perform R and D work at three national laboratories. Much work has already taken place, with the first prototypical cameras operational at 13.4 nm using low energy laser plasma EUV light sources to investigate issues including the source, camera, electro- mechanical and system issues, photoresists, and of course the masks. EUV lithograph masks are fundamentally different than conventional photolithographic masks as they are reflective instead of transmissive. EUV light at 13.4 nm is rapidly absorbed by most materials, thus all light transmission within the EUVL system from source to silicon wafer, including EUV reflected from the mask, is performed by multilayer mirrors in vacuum.
Single-pixel computational ghost imaging with helicity-dependent metasurface hologram.
Liu, Hong-Chao; Yang, Biao; Guo, Qinghua; Shi, Jinhui; Guan, Chunying; Zheng, Guoxing; Mühlenbernd, Holger; Li, Guixin; Zentgraf, Thomas; Zhang, Shuang
2017-09-01
Different optical imaging techniques are based on different characteristics of light. By controlling the abrupt phase discontinuities with different polarized incident light, a metasurface can host a phase-only and helicity-dependent hologram. In contrast, ghost imaging (GI) is an indirect imaging modality to retrieve the object information from the correlation of the light intensity fluctuations. We report single-pixel computational GI with a high-efficiency reflective metasurface in both simulations and experiments. Playing a fascinating role in switching the GI target with different polarized light, the metasurface hologram generates helicity-dependent reconstructed ghost images and successfully introduces an additional security lock in a proposed optical encryption scheme based on the GI. The robustness of our encryption scheme is further verified with the vulnerability test. Building the first bridge between the metasurface hologram and the GI, our work paves the way to integrate their applications in the fields of optical communications, imaging technology, and security.
Single-pixel computational ghost imaging with helicity-dependent metasurface hologram
Liu, Hong-Chao; Yang, Biao; Guo, Qinghua; Shi, Jinhui; Guan, Chunying; Zheng, Guoxing; Mühlenbernd, Holger; Li, Guixin; Zentgraf, Thomas; Zhang, Shuang
2017-01-01
Different optical imaging techniques are based on different characteristics of light. By controlling the abrupt phase discontinuities with different polarized incident light, a metasurface can host a phase-only and helicity-dependent hologram. In contrast, ghost imaging (GI) is an indirect imaging modality to retrieve the object information from the correlation of the light intensity fluctuations. We report single-pixel computational GI with a high-efficiency reflective metasurface in both simulations and experiments. Playing a fascinating role in switching the GI target with different polarized light, the metasurface hologram generates helicity-dependent reconstructed ghost images and successfully introduces an additional security lock in a proposed optical encryption scheme based on the GI. The robustness of our encryption scheme is further verified with the vulnerability test. Building the first bridge between the metasurface hologram and the GI, our work paves the way to integrate their applications in the fields of optical communications, imaging technology, and security. PMID:28913433
NASA Astrophysics Data System (ADS)
Palagi, Stefano; Mark, Andrew G.; Reigh, Shang Yik; Melde, Kai; Qiu, Tian; Zeng, Hao; Parmeggiani, Camilla; Martella, Daniele; Sanchez-Castillo, Alberto; Kapernaum, Nadia; Giesselmann, Frank; Wiersma, Diederik S.; Lauga, Eric; Fischer, Peer
2016-06-01
Microorganisms move in challenging environments by periodic changes in body shape. In contrast, current artificial microrobots cannot actively deform, exhibiting at best passive bending under external fields. Here, by taking advantage of the wireless, scalable and spatiotemporally selective capabilities that light allows, we show that soft microrobots consisting of photoactive liquid-crystal elastomers can be driven by structured monochromatic light to perform sophisticated biomimetic motions. We realize continuum yet selectively addressable artificial microswimmers that generate travelling-wave motions to self-propel without external forces or torques, as well as microrobots capable of versatile locomotion behaviours on demand. Both theoretical predictions and experimental results confirm that multiple gaits, mimicking either symplectic or antiplectic metachrony of ciliate protozoa, can be achieved with single microswimmers. The principle of using structured light can be extended to other applications that require microscale actuation with sophisticated spatiotemporal coordination for advanced microrobotic technologies.
NASA Astrophysics Data System (ADS)
Kawashima, Hayato; Yamaji, Masahiro; Suzuki, Jun'ichi; Tanaka, Shuhei
2011-03-01
We report an invisible two-dimensional (2D) barcode embedded into a synthetic fused silica by femtosecond laser processing using a computer-generated hologram (CGH) that generates a spatially extended femtosecond pulse beam in the depth direction. When we illuminate the irradiated 2D barcode pattern with a 254 nm ultraviolet (UV) light, a strong red photoluminescence (PL) is observed, and we can read it by using a complementary metal oxide semiconductor (CMOS) camera and image processing technology. This work provides a novel barcode fabrication method by femtosecond laser processing using a CGH and a barcode reading method by a red PL.
Motility, Force Generation, and Energy Consumption of Unicellular Parasites.
Hochstetter, Axel; Pfohl, Thomas
2016-07-01
Motility is a key factor for pathogenicity of unicellular parasites, enabling them to infiltrate and evade host cells, and perform several of their life-cycle events. State-of-the-art methods of motility analysis rely on a combination of optical tweezers with high-resolution microscopy and microfluidics. With this technology, propulsion forces, energies, and power generation can be determined so as to shed light on the motion mechanisms, chemotactic behavior, and specific survival strategies of unicellular parasites. With these new tools in hand, we can elucidate the mechanisms of motility and force generation of unicellular parasites, and identify ways to manipulate and eventually inhibit them. Copyright © 2016 Elsevier Ltd. All rights reserved.
Engineering Strain for Improved III-Nitride Optoelectronic Device Performance
NASA Astrophysics Data System (ADS)
Van Den Broeck, Dennis Marnix
Due to growing environmental and economic concerns, renewable energy generation and high-efficiency lighting are becoming even more important in the scientific community. III-Nitride devices have been essential in production of high-brightness light-emitting diodes (LEDs) and are now entering the photovoltaic (PV) realm as the technology advances. InGaN/GaN multiple quantum well LEDs emitting in the blue/green region have emerged as promising candidates for next-generation lighting technologies. Due to the large lattice mismatch between InN and GaN, large electric fields exist within the quantum well layers and result in low rates of radiative recombination, especially for the green spectral region. This is commonly referred to as the "green gap" and results in poor external quantum efficiencies for light-emitting diodes and laser diodes. In order to mitigate the compressive stress of InGaN QWs, a novel growth technique is developed in order to grown thick, strain-relaxed In yGa1-yN templates for 0.08 < y < 0.11. By inserting 2 nm GaN interlayers into the growing InyGa1-yN film, and subsequently annealing the structure, "semibulk" InGaN templates were achieved with vastly superior crystal and optical properties than bulk InGaN films. These semibulk InGaN templates were then utilized as new templates for multiple quantum well active layers, effectively reducing the compressive strain in the InGaN wells due to the larger lattice constant of the InGaN template with respect to a GaN template. A zero-stress balance method was used in order to realize a strain-balanced multiple quantum well structure, which again showed improved optical characteristics when compared to fully-strain active regions. The semibulk InGaN template was then implemented into "strain-compensated" LED structures, where light emission was achieved with very little leakage current. Discussion of these strain-compensated devices compared to conventional LEDs is detailed.
Tunc, Elif Pak
2007-06-01
Exothermic composite resin chemical reactions and visible light generators can produce heat during a restorative polymerization process. These thermal changes in restored teeth may cause pain and irreversible pulpitis. The purpose of this study was to analyze the temperature distribution and heat flow patterns of a crowned mandibular second premolar tooth model using 3 different light-polymerization technologies and a finite element technique. A 2-dimensional finite element model was used to simulate a clinical condition. Heat flow and thermal stress distribution in a tooth during cementation of an all-ceramic crown using 4 commercially available light-polymerization units (LPUs), each with different wavelengths (Elipar TriLight, Elipar Freelight, Apollo 95 E, and ADT 1000 PAC), were investigated. The temperature values were measured at 3, 10, 12, and 40 seconds for each light-polymerizing unit (LPU) at 6 different finite element nodes. Two-dimensional temporal and spatial distribution of the thermal stress within the tooth, including the thermal coefficients and boundary conditions of the dental materials, were obtained and evaluated. The temperature at the nodal points did not exceed 42 degrees C, which is a threshold value for tissue vitality within the recommended operating periods at the dentin and pulp surface for all LPUs, except for Elipar TriLight. In the case of Elipar TriLlight, the temperatures at the dentin and pulp surfaces were 47 degrees C and 42 degrees C, respectively. When the light-polymerization units were used according to the manufacturers' operating procedures and without prolonged operating periods, with the exception of Elipar TriLight, the investigated LPUs did not produce significant heat. However, when the operating periods were prolonged, unacceptable temperature increases were observed, especially with the high-intensity LPUs.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gust, Devens; Moore, Thomas A.; Moore, Ana L.
OAK B188 The goal of this project is to mimic the energy transduction processes by which photosynthetic organisms harvest sunlight and convert it to forms of energy that are more easily used and stored. The results may lead to new technologies for solar energy harvesting based on the natural photosynthetic process. They may also enrich our understanding and control of photosynthesis in living organisms, and lead to methods for increasing natural biomass production, carbon dioxide removal, and oxygen generation. In our work to date, we have learned how to make synthetic antenna and reaction center molecules that absorb light andmore » undergo photoinduced electron transfer to generate long-lived, energetic charge-separated states. We have assembled a prototype system in which artificial reaction centers are inserted into liposomes (artificial cell-like constructs), where they carry out light-driven transmembrane translocation of hydrogen ions to generate proton motive force. By insertion of natural ATP synthase into the liposomal bilayer, this proton motive force has been used to power the synthesis of ATP. ATP is a natural biological energy currency. We are carrying out a systematic investigation of these artificial photosynthetic energy harvesting constructs in order to understand better how they operate. In addition, we are exploring strategies for reversing the direction of the light-powered proton pumping. Most recently, we have extended these studies to develop a light-powered transmembrane calcium ion pump that converts sunlight into energy stored as a calcium ion concentration gradient across a lipid bilayer.« less
MEMS Microshutter Arrays for James Webb Space Telescope
NASA Technical Reports Server (NTRS)
Li, Mary J.; Beamesderfer, Michael; Babu, Sachi; Bajikar, Sateesh; Ewin, Audrey; Franz, Dave; Hess, Larry; Hu, Ron; Jhabvala, Murzy; Kelly, Dan;
2006-01-01
MEMS microshutter arrays are being developed at NASA Goddard Space Flight Center for use as an aperture array for a Near-Infrared Spectrometer (NirSpec). The instruments will be carried on the James Webb Space Telescope (JWST), the next generation of space telescope after Hubble Space Telescope retires. The microshutter arrays are designed for the selective transmission of light with high efficiency and high contrast, Arrays are close-packed silicon nitride membranes with a pixel size of 100x200 microns. Individual shutters are patterned with a torsion flexure permitting shutters to open 90 degrees with a minimized mechanical stress concentration. Light shields are made on to each shutter for light leak prevention so to enhance optical contrast, Shutters are actuated magnetically, latched and addressed electrostatically. The shutter arrays are fabricated using MEMS technologies.
OLED integrated silicon membranes for light-modulation devices
NASA Astrophysics Data System (ADS)
Cheneler, David; Vervaeke, Michael; Thienpont, Hugo; Lambertini, Vito G.; Brignone, Mauro
2014-05-01
Organic light-emitting diodes (OLEDs) are most frequently used for display purposes and while they have also been utilized in sensing applications, their innate compliance has not previously been exploited for these applications. However, in this manuscript it is shown that OLEDs are compatible with microfabrication methods used in the production of micro mechanical devices. In particular it is shown that the compliance of OLEDs can be utilized in, and not limited to, a new generation of opto-mechanical pressure sensors. A fabrication process for a light-modulating pressure sensor is described. Prototypes were fabricated and tested and the response compared to an analytical theory developed by the authors. It is shown with simple circuitry, a resolution of 11.4 Pa up to 350 kPa is attainable using this technology.
Evaluation of OLED and edge-lit LED lighting panels
NASA Astrophysics Data System (ADS)
Mou, Xi; Narendran, Nadarajah; Zhu, Yiting; Freyssinier, Jean Paul
2016-09-01
Solid-state lighting (SSL) offers a new technology platform for lighting designers and end-users to illuminate spaces with low energy demand. Two types of SSL sources include organic light-emitting diodes (OLEDs) and light-emitting diodes (LEDs). OLED is an area light source, and its primary competing technology is the edge-lit LED panel. Generally, both of these technologies are considered similar in shape and appearance, but there is little understanding of how people perceive discomfort glare from large area light sources. The objective of this study was to evaluate discomfort glare for the two lighting technologies under similar operating conditions by gathering observers' reactions. The human factors study results showed no statistically significant difference in human response to discomfort glare between OLED and edge-lit LED panels when the two light sources produced the same lighting stimulus. This means both technologies appeared equally glary beyond a certain luminance.
Prospective communications research to support fly by light/power by wire
NASA Technical Reports Server (NTRS)
Game, David
1994-01-01
A NASA Research Grant NAG-1-1309, Distributed Fiber Optic Systems for Commercial Aircraft, was awarded during July 1991. This report primarily constitutes a summary of findings of the original background research done at that time. NASA is embarking on a research project to design the next generation of commercial aircraft, fly by light/power by wire. The objectives of this effort are to improve commercial aircraft design by (1) reducing the weight of the aircraft to improve efficiency and (2) improving the fault tolerance and safety of the aircraft by enhancing current systems with new technologies or introducing new systems into the aircraft.
Phase sensitive amplification in integrated waveguides (Conference Presentation)
NASA Astrophysics Data System (ADS)
Schroeder, Jochen B.; Zhang, Youngbin; Husko, Chad A.; LeFrancois, Simon; Eggleton, Benjamin J.
2017-02-01
Phase sensitive amplification (PSA) is an attractive technology for integrated all-optical signal processing, due to it's potential for noiseless amplification, phase regeneration and generation of squeezed light. In this talk I will review our results on implementing four-wave-mixing based PSA inside integrated photonic devices. In particular I will discuss PSA in chalcogenide ridge waveguides and silicon slow-light photonic crystals. We achieve PSA in both pump- and signal-degenerate schemes with maximum extinction ratios of 11 (silicon) and 18 (chalcogenide) dB. I will further discuss the influence of two-photon absorption and free carrier effects on the performance of silicon-based PSAs.
A compact 500 MHz 4 kW Solid-State Power Amplifier for accelerator applications
NASA Astrophysics Data System (ADS)
Gaspar, M.; Pedrozzi, M.; Ferreira, L. F. R.; Garvey, T.
2011-05-01
We present the development of a compact narrow-band Solid-State Power Amplifier (SSPA). We foresee a promising application of solid-state amplifiers specifically in accelerators for new generation synchrotron light sources. Such a new technology has reached a competitive price/performance ratio and expected lifetime in comparison with klystron and IOT amplifiers. The increasing number of synchrotron light sources using 500 MHz as base frequency justifies the effort in the development of the proposed amplifier. Two different techniques are also proposed to improve the control and performance of these new distributed amplification systems which we call, respectively, complete distributed system and forced compression.
Solar transformation: Sun on the reservation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Epstein, R.T.
1994-01-01
To most Americans, the simple act of flicking on the light is as taken for granted as breathing air-without so much as a thought about its possible environmental consequences. But to Sylvia Brownskill and hundreds on the New Mexico Navajo Indian reservation, accessing electricity without harming the environment is of the utmost importance-and until recently, virtually impossible. Four years ago, however, practical technology for producing {open_quotes}clean{close_quotes} energy became available, and now even in the most remote locations of the reservation can flick on a light switch, knowing that the electricity generated is produced in its entirety by the power ofmore » the sun.« less
Entanglement and asymmetric steering over two octaves of frequency difference
NASA Astrophysics Data System (ADS)
Olsen, M. K.
2017-12-01
The development of quantum technologies which use quantum states of the light field interacting with other systems creates a demand for entangled states spanning wide frequency ranges. In this work we analyze a parametric scheme of cascaded harmonic generation which promises to deliver bipartite entangled states in which the two modes are separated by two octaves in frequency. This scheme is potentially very useful for applications in quantum communication and computation networks as well as providing for quantum interfaces between a wider range of light and atomic ensembles than is presently practicable. It doubles the frequency range over which entanglement is presently available.
Osorio-Vargas, Paula A; Pulgarin, Cesar; Sienkiewicz, Andrzej; Pizzio, Luis R; Blanco, Mirta N; Torres-Palma, Ricardo A; Pétrier, Christian; Rengifo-Herrera, Julián A
2012-05-01
Low-frequency ultrasound (LFUS) irradiation induces morphological, optical and surface changes in the commercial nano-TiO(2)-based photocatalyst, Evonik-Degussa P-25. Low-temperature electron spin resonance (ESR) measurements performed on this material provided the first experimental evidence for the formation of oxygen vacancies (V(o)), which were also found responsible for the visible-light absorption. The V(o) surface defects might result from high-speed inter-particle collisions and shock waves generated by LFUS sonication impacting the TiO(2) particles. This is in contrast to a number of well-established technologies, where the formation of oxygen vacancies on the TiO(2) surface often requires harsh technological conditions and complicated procedures, such as annealing at high temperatures, radio-frequency-induced plasma or ion sputtering. Thus, this study reports for the first time the preparation of visible-light responsive TiO(2)-based photocatalysts by using a simple LFUS-based approach to induce oxygen vacancies at the nano-TiO(2) surface. These findings might open new avenues for synthesis of novel nano-TiO(2)-based photocatalysts capable of destroying water or airborne pollutants and microorganisms under visible light illumination. Copyright © 2011 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Kakinuma, Koichiro
2006-05-01
The development of light-emitting diode (LED) backlight a wide-color-gamut and mercury-free has become active in liquid crystal display (LCD) industry. Reports on the development of backlights, such as a direct illumination-type back-light and a guided light illumination-type LED backlight were published. The fabrication of an actual commercial product has been progressing under this active development. Sony Corporation launched an LED-backlit LCD television (TV) model, dubbed QUALIA 005, the world’s first home-use television featuring LED backlighting. This product offers a very wide color reproduction range, delivering a color gamut of 150% of that typically achieved by conventional televisions. In this paper, the background of the development of the LED backlight system “TriluminosTM” and the technologies used to realize the wide color gamut are discussed. The main issues to be solved for the commercialization were how to reduce the brightness/color non uniformity of the backlight and how to treat heat generation from the LED. The standardization of wide color space definition xvYCC and LED backlight LCD television combination is expected to result in a more vivid and correct color expression, and a forecast that extends to the market in the future.
Invisible Light: a global infotainment community based on augmented reality technologies
NASA Astrophysics Data System (ADS)
Israel, Kai; Wozniak, Peter; Vauderwange, Oliver; Curticapean, Dan
2015-10-01
Theoretical details about optics and photonics are not common knowledge nowadays. Physicists are keen to scientifically explain `light,' which has a huge impact on our lives. It is necessary to examine it from multiple perspectives and to make the knowledge accessible to the public in an interdisciplinary, scientifically well-grounded and appealing medial way. To allow an information exchange on a global scale, our project "Invisible Light" establishes a worldwide accessible platform. Its contents will not be created by a single instance, but user-generated, with the help of the global community. The article describes the infotainment portal "Invisible Light," which stores scientific articles about light and photonics and makes them accessible worldwide. All articles are tagged with geo-coordinates, so they can be clearly identified and localized. A smartphone application is used for visualization, transmitting the information to users in real time by means of an augmented reality application. Scientific information is made accessible for a broad audience and in an attractive manner.
Hubenova, Yolina; Mitov, Mario
2012-10-01
In the present study we demonstrate for the first time the possibility for conversion of solar energy into electricity on the principles of Direct Photosynthetic Plant Fuel Cell (DPPFC) technology by using aquatic higher plants. Lemna minuta duckweed was grown autotrophically in specially constructed fuel cells under sunlight irradiation and laboratory lighting. Current and power density up to 1.62±0.10 A.m(-2) and 380±19 mW.m(-2), respectively, were achieved under sunlight conditions. The influence of the temperature, light intensity and day/night sequencing on the current generation was investigated. The importance of the light intensity was demonstrated by the higher values of generated current (at permanently connected resistance) during daytime than those through the nights, indicating the participation of light-dependent photosynthetic processes. The obtained DPPFC outputs in the night show the contribution of light-independent reactions (respiration). The electron transfer in the examined DPPFCs is associated with a production of endogenous mediator, secreted by the duckweed. The plants' adaptive response to the applied polarization is also connected with an enhanced metabolism resulting in an increase of the protein and carbohydrate intracellular content. Further investigations aiming at improvement of the DPPFC outputs and elucidation of the electron transfer mechanism are required for practical application. Copyright © 2012 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Hofmann, James A.
An increasing threat to the aviation industry is laser light illumination on airplanes during critical phases of flight. If a laser hits the cockpit, it not only distracts the pilots, but it can cause flash blindness or permanently damage the vision of the pilots. This research attempts to mitigate these lasers illuminations through the application of both liquid crystal (LC's) technologies and dye sensitized solar cell (DSSC) technologies. The LC of choice is N-(4-Methoxybenzylidene)-4-butylaniline, or MBBA, because it has special optical properties including the ability to undergo phase transitions when exposed to an electric field. By applying an external electric field, MBBA switches from its transparent nematic phase, to its non-transparent crystalline phase, blocking the laser light. This research optimized the application of MBBA by reducing the triggering voltage and relaxation time of the LC using spacer thicknesses and scratching techniques. The liquid to solid phase transition was reduced to a 3V differential, and the time required for the crystals to relax into its transparent liquid phase was reduced to less than ten seconds. The phase transition was studied using an external electric field generated by DSSCs constructed from a titanium dioxide (TiO2) nanocomposite layer coated with dye. To maximize the voltage output by the DSSCs, layer thickness and dye sensitizer were studied to investigate their impact on the performance of the DSSC when illuminated by solar lamps and green light (532nm). Three different layer thicknesses and five different dyes were tested: Eosin Y, Eriochrome Black, Congo Red, Fast Green, and Alizarine Yellow. The experimental results showed a thin layer of nanocomposite sensitized with Eosin Y dye produced the most efficient DSSCs for the scope of this research. Experimental testing showed the DSSCs can generate 381 +/- 10mV under solar lamp exposure, 356 +/- 10mV under laser light exposure, and a voltage increase of 60 +/- 16mV when exposed to both light sources. Additionally, the performance of the DSSCs were correlated to molecular modeling predictions using Spartan software. The stability of TiO2-dye interactions indicated that dye adsorption to the surface of the nanocomposite directly impacted the performance of the DSSCs. Implementation of a LC and DSSC system forces the LCs to transition between its nematic and crystalline phases depending on the wavelength of light that is illuminating the DSSC. This research explores the practicality of using LCs and DSSCs as a preliminary approach to mitigating green laser light illumination on aircraft. Experimental results have shown that DSSCs alone are not capable of forcing a phase transitions in LCs which can entirely mitigate incoming laser light. The intense laser light required to generate substantial voltage (3V) from the DSSCs penetrates the crystalline phase of the LC with minimal attenuation of 5%.
Generation of a spiral wave using amplitude masks
NASA Astrophysics Data System (ADS)
Anguiano-Morales, Marcelino; Salas-Peimbert, Didia P.; Trujillo-Schiaffino, Gerardo
2011-09-01
Optical beams of Bessel-type whose transverse intensity profile remains unchanged under free-space propagation are called nondiffracting beams. Experimentally, Durnin used an annular slit on the focal plane of a convergent lens to generate a Bessel beam. However, this configuration is only one of many that can be used to generate nondiffracting beams. The method can be modified in order to generate a required phase distribution in the beam. In this work, we propose a simple and effective method to generate spiral beams whose intensity remains invariant during propagation using amplitude masks. Laser beams with spiral phase, i.e., vortex beams have attracted great interest because of their possible use in different applications for areas ranging from laser technologies, medicine, and microbiology to the production of light tweezers and optical traps. We present a study of spiral structures generated by the interference between two incomplete annular beams.
Miller, L. B.; Donohoe, S. P.; Jones, M. H.; ...
2015-04-22
This article reports on the testing and comparison of a prototype hydrogen fuel cell light tower (H2LT) and a conventional diesel-powered metal halide light trailer for use in road maintenance and construction activities. The prototype was originally outfitted with plasma lights and then with light-emitting diode (LED) luminaires. Light output and distribution, lighting energy efficiency (i.e., efficacy), power source thermal efficiency, and fuel costs are compared. The metal halide luminaires have 2.2 and 3.1 times more light output than the plasma and LED luminaires, respectively, but they require more power/lumen to provide that output. The LED luminaires have 1.6 timesmore » better light efficacy than either the metal halide or plasma luminaires. The light uniformity ratios produced by the plasma and LED towers are acceptable. The fuel cell thermal efficiency at the power required to operate the plasma lights is 48%, significantly higher than the diesel generator efficiency of 23% when operating the metal halide lights. Due to the increased efficiency of the fuel cell and the LED lighting, the fuel cost per lumen-hour of the H2LT is 62% of the metal halide diesel light tower assuming a kilogram of hydrogen is twice the cost of a gallon of diesel fuel.« less
White LEDs and modules in chip-on-board technology for general lighting
NASA Astrophysics Data System (ADS)
Hartmann, Paul; Wenzl, Franz P.; Sommer, Christian; Pachler, Peter; Hoschopf, Hans; Schweighart, Marko; Hartmann, Martin; Kuna, Ladislav; Jakopic, Georg; Leising, Guenther; Tasch, Stefan
2006-08-01
At present, light-emitting diode (LED) modules in various shapes are developed and designed for the general lighting, advertisement, emergency lighting, design and architectural markets. To compete with and to surpass the performance of traditional lighting systems, enhancement of Lumen output and the white light quality as well as the thermal management and the luminary integration are key factors for success. Regarding these issues, white LEDs based on the chip-on-board (COB) technology show pronounced advantages. State-of-the-art LEDs exploiting this technology are now ready to enter the general lighting segments. We introduce and discuss the specific properties of the Tridonic COB technology dedicated for general lighting. This technology, in combination with a comprehensive set of tools to improve and to enhance the Lumen output and the white light quality, including optical simulation, is the scaffolding for the application of white LEDs in emerging areas, for which an outlook will be given.
Photolytically driven generation of dissolved oxygen and increased oxyhemoglobin in whole blood.
Monzyk, Bruce F; Burckle, Eric C; Carleton, Linda M; Busch, James; Dasse, Kurt A; Martin, Peter M; Gilbert, Richard J
2006-01-01
The severely debilitating nature of chronic lung disease has long provided the impetus for the development of technologies to supplement the respiratory capacity of the human lung. Although conventional artificial lung technologies function by delivering pressurized oxygen to the blood through a system of hollow fibers or tubes, our approach uses photolytic energy to generate dissolved oxygen (DO) from the water already present in blood, thus eliminating the need for gas delivery. We have previously demonstrated that it is feasible to generate dissolved oxygen from water based on UVA illumination of a highly absorbent TiO2 thin film. In the current study, we extend this work by using photolytic energy to generate DO from whole blood, thus resulting in an increase of oxyhemoglobin as a function of back side TiO2 surface film illumination. Initial experiments, performed with Locke's Ringer solution, demonstrated effective film thickness and material selection for the conductive layer. The application of a small bias voltage was used to conduct photogenerated electrons from the aqueous phase to minimize electron recombination with the DO.Mixed arterial-venous bovine blood was flowed in a recirculating loop over TiO2 nanocrystalline films illuminated on the side opposite the blood (or "back side") to eliminate the possibility of any direct exposure of blood to light. After light exposure of the TiO2 film, the fraction of oxyhemoglobin in the blood rapidly increased to near saturation and remained stable throughout the trial period. Last, we evaluated potential biofouling of the DO generating surface by scanning electron microscopy, after photolytically energized DO generation in whole blood, and observed no white or red blood cell surface deposition, nor the accumulation of any other material at this magnification. We conclude that it is feasible to photolytically oxygenate the hemoglobin contained in whole blood with oxygen derived from the blood's own water content without involving a gaseous phase.
Bae, Kyuyoung; Kang, Gumin; Cho, Suehyun K; Park, Wounjhang; Kim, Kyoungsik; Padilla, Willie J
2015-12-14
Solar steam generation has been achieved by surface plasmon heating with metallic nanoshells or nanoparticles, which have inherently narrow absorption bandwidth. For efficient light-to-heat conversion from a wider solar spectrum, we employ adiabatic plasmonic nanofocusing to attain both polarization-independent ultrabroadband light absorption and high plasmon dissipation loss. Here we demonstrate large area, flexible thin-film black gold membranes, which have multiscale structures of varying metallic nanoscale gaps (0-200 nm) as well as microscale funnel structures. The adiabatic nanofocusing of self-aggregated metallic nanowire bundle arrays produces average absorption of 91% at 400-2,500 nm and the microscale funnel structures lead to average reflection of 7% at 2.5-17 μm. This membrane allows heat localization within the few micrometre-thick layer and continuous water provision through micropores. We efficiently generate water vapour with solar thermal conversion efficiency up to 57% at 20 kW m(-2). This new structure has a variety of applications in solar energy harvesting, thermoplasmonics and related technologies.
NASA Astrophysics Data System (ADS)
Tsai, Chun-Wei; Lyu, Bo-Han; Wang, Chen; Hung, Cheng-Chieh
2017-05-01
We have already developed multi-function and easy-to-use modulation software that was based on LabVIEW system. There are mainly four functions in this modulation software, such as computer generated holograms (CGH) generation, CGH reconstruction, image trimming, and special phase distribution. Based on the above development of CGH modulation software, we could enhance the performance of liquid crystal on silicon - spatial light modulator (LCoSSLM) as similar as the diffractive optical element (DOE) and use it on various adaptive optics (AO) applications. Through the development of special phase distribution, we are going to use the LCoS-SLM with CGH modulation software into AO technology, such as optical microscope system. When the LCOS-SLM panel is integrated in an optical microscope system, it could be placed on the illumination path or on the image forming path. However, LCOS-SLM provides a program-controllable liquid crystal array for optical microscope. It dynamically changes the amplitude or phase of light and gives the obvious advantage, "Flexibility", to the system
Bae, Kyuyoung; Kang, Gumin; Cho, Suehyun K.; Park, Wounjhang; Kim, Kyoungsik; Padilla, Willie J.
2015-01-01
Solar steam generation has been achieved by surface plasmon heating with metallic nanoshells or nanoparticles, which have inherently narrow absorption bandwidth. For efficient light-to-heat conversion from a wider solar spectrum, we employ adiabatic plasmonic nanofocusing to attain both polarization-independent ultrabroadband light absorption and high plasmon dissipation loss. Here we demonstrate large area, flexible thin-film black gold membranes, which have multiscale structures of varying metallic nanoscale gaps (0–200 nm) as well as microscale funnel structures. The adiabatic nanofocusing of self-aggregated metallic nanowire bundle arrays produces average absorption of 91% at 400–2,500 nm and the microscale funnel structures lead to average reflection of 7% at 2.5–17 μm. This membrane allows heat localization within the few micrometre-thick layer and continuous water provision through micropores. We efficiently generate water vapour with solar thermal conversion efficiency up to 57% at 20 kW m−2. This new structure has a variety of applications in solar energy harvesting, thermoplasmonics and related technologies. PMID:26657535
New-generation radiofrequency technology.
Krueger, Nils; Sadick, Neil S
2013-01-01
Radiofrequency (RF) technology has become a standard treatment in aesthetic medicine with many indications due to its versatility, efficacy, and safety. It is used worldwide for cellulite reduction; acne scar revision; and treatment of hypertrophic scars and keloids, rosacea, and inflammatory acne in all skin types. However, the most common indication for RF technology is the nonablative tightening of tissue to improve skin laxity and reduce wrinkles. Radiofrequency devices are classified as unipolar, bipolar, or multipolar depending on the number of electrodes used. Additional modalities include fractional RF; sublative RF; phase-controlled RF; and combination RF therapies that apply light, massage, or pulsed electromagnetic fields (PEMFs). This article reviews studies and case series on these devices. Radiofrequency technology for aesthetic medicine has seen rapid advancements since it was used for skin tightening in 2003. Future developments will continue to keep RF technology at the forefront of the dermatologist's armamentarium for skin tightening and rejuvenation.
Advanced lighting guidelines: 1993. Final report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Eley, C.; Tolen, T.M.; Benya, J.R.
1993-12-31
The 1993 Advanced Lighting Guidelines document consists of twelve guidelines that provide an overview of specific lighting technologies and design application techniques utilizing energy-efficient lighting practice. Lighting Design Practice assesses energy-efficient lighting strategies, discusses lighting issues, and explains how to obtain quality lighting design and consulting services. Luminaires and Lighting Systems surveys luminaire equipment designed to take advantage of advanced technology lamp products and includes performance tables that allow for accurate estimation of luminaire light output and power input. The additional ten guidelines -- Computer-Aided Lighting Design, Energy-Efficient Fluorescent Ballasts, Full-Size Fluorescent Lamps, Compact Fluorescent Lamps, Tungsten-Halogen Lamps, Metal Halidemore » and HPS Lamps, Daylighting and Lumen Maintenance, Occupant Sensors, Time Scheduling Systems, and Retrofit Control Technologies -- each provide a product technology overview, discuss current products on the lighting equipment market, and provide application techniques. This document is intended for use by electric utility personnel involved in lighting programs, lighting designers, electrical engineers, architects, lighting manufacturers` representatives, and other lighting professionals.« less
A critical reflection on the technological development of deep brain stimulation (DBS)
Ineichen, Christian; Glannon, Walter; Temel, Yasin; Baumann, Christian R.; Sürücü, Oguzkan
2014-01-01
Since the translational research findings of Benabid and colleagues which partly led to their seminal paper regarding the treatment of mainly tremor-dominant Parkinson patients through thalamic high-frequency-stimulation (HFS) in 1987, we still struggle with identifying a satisfactory mechanistic explanation of the underlying principles of deep brain stimulation (DBS). Furthermore, the technological advance of DBS devices (electrodes and implantable pulse generators, IPG’s) has shown a distinct lack of dynamic progression. In light of this we argue that it is time to leave the paleolithic age and enter hellenistic times: the device-manufacturing industry and the medical community together should put more emphasis on advancing the technology rather than resting on their laurels. PMID:25278864
Holographic spectrum-splitting optical systems for solar photovoltaics
NASA Astrophysics Data System (ADS)
Zhang, Deming
Solar energy is the most abundant source of renewable energy available. The relatively high cost prevents solar photovoltaic (PV) from replacing fossil fuel on a larger scale. In solar PV power generation the cost is reduced with more efficient PV technologies. In this dissertation, methods to improve PV conversion efficiency with holographic optical components are discussed. The tandem multiple-junction approach has achieved very high conversion efficiency. However it is impossible to manufacture tandem PV cells at a low cost due to stringent fabrication standards and limited material types that satisfy lattice compatibility. Current produced by the tandem multi-junction PV cell is limited by the lowest junction due to series connection. Spectrum-splitting is a lateral multi-junction concept that is free of lattice and current matching constraints. Each PV cell can be optimized towards full absorption of a spectral band with tailored light-trapping schemes. Holographic optical components are designed to achieve spectrum-splitting PV energy conversion. The incident solar spectrum is separated onto multiple PV cells that are matched to the corresponding spectral band. Holographic spectrum-splitting can take advantage of existing and future low-cost technologies that produces high efficiency thin-film solar cells. Spectrum-splitting optical systems are designed and analyzed with both transmission and reflection holographic optical components. Prototype holograms are fabricated and high optical efficiency is achieved. Light-trapping in PV cells increases the effective optical path-length in the semiconductor material leading to improved absorption and conversion efficiency. It has been shown that the effective optical path length can be increased by a factor of 4n2 using diffusive surfaces. Ultra-light-trapping can be achieved with optical filters that limit the escape angle of the diffused light. Holographic reflection gratings have been shown to act as angle-wavelength selective filters that can function as ultra-light-trapping filters. Results from an experimental reflection hologram are used to model the absorption enhancement factor for a silicon solar cell and light-trapping filter. The result shows a significant improvement in current generation for thin-film silicon solar cells under typical operating conditions.
Air Force Science & Technology Issues & Opportunities Regarding High Performance Embedded Computing
2009-09-23
Challenges by Domain * Air: Persistent air dominance is at risk * Increasingly effective air defenses * Proliferation of 5th generation fighters, cheap cruise missiles, and UASs * Light-speed war possibilities are terrifying * Space: Now a contested domain * Increasingly important * Increasingly vulnerable * Cyber: Cyber warfare has begun * We don’t control the battlespace * We rely on it more and more * We can’t find the enemy.
Interface of Science, Technology and Security: Areas of Most Concern, Now and Ahead
2017-03-28
connectivity is creating new forms of security threats and exploitable instabilities. There is a need to develop secure software to reduce vulnerabilities...implications in the light of global population growth, industrialization and limited fossil fuel supplies. The continued improvement of generation, storage...national strategic concern is when the S&T-security nexus creates opportunities for misunderstanding. These opportunities assume two forms , rooted in
Elman, Monica; Vider, Itzhak; Harth, Yoram; Gottfried, Varda; Shemer, Avner
2010-04-01
Abstract The last few years have shown an increased demand for non-invasive skin tightening to improve body contour. Since light (lasers or intense pulsed light sources) has a limited ability to penetrate deep into the tissue, radio frequency (RF) modalities were introduced for the reduction of lax skin to achieve skin tightening and body circumference reduction. This study presents the use of the novel 3DEEP technology for body contouring. 3DEEP is a next generation RF technology that provides targeted heating to deeper skin layers without pain or other local or systemic side effects associated with the use of the earlier generation RF systems available today. The study included 30 treatment areas on 23 healthy volunteers at two sites. The treatment protocol included four weekly and two bi-weekly (n= 6) treatments on different body areas. Results were evaluated by standardized photography and by circumference measurements at the treatment area, and were compared to changes in body weight. Significant improvement could be observed in wrinkles and skin laxity, and in the appearance of stretch marks and cellulite. Some changes appeared as early as after a single treatment. Circumference changes of up to 4.3 cm were measured.
Near-infrared (NIR) optogenetics using up-conversion system
NASA Astrophysics Data System (ADS)
Hososhima, Shoko; Yuasa, Hideya; Ishizuka, Toru; Yawo, Hiromu
2015-03-01
Non-invasive remote control technologies designed to manipulate neural functions for a comprehensive and quantitative understanding of the neuronal network in the brain as well as for the therapy of neurological disorders have long been awaited. Recently, it has become possible to optically manipulate the neuronal activity using biological photo-reactive molecules such as channelrhodopsin-2 (ChR2). However, ChR2 and its relatives are mostly reactive to visible light which does not effectively penetrate through biological tissues. In contrast, near-infrared (NIR) light penetrates deep into the tissues because biological systems are almost transparent to light within this so-called `imaging window'. Here we used lanthanide nanoparticles (LNPs), which are composed of rare-earth elements, as luminous bodies to activate channelrhodopsins (ChRs) since they absorb low-energy NIR light to emit high-energy visible light (up-conversion). Neuron-glioma-hybrid ND-7/23 cells were cultured with LNP(NaYF4:Sc/Yb/Er) particles (peak emission, 543 nm) and transfected to express C1V1 (peak absorbance, 539 nm), a chimera of ChR1 and VChR1. The photocurrents were generated in response to NIR laser light (976 nm) to a level comparable to that evoked by a filtered Hg lamp (530-550 nm). NIR light pulses also evoked action potentials in the cultured neurons that expressed C1V1. It is suggested that the green luminescent light emitted from LNPs effectively activated C1V1 to generate the photocurrent. With the optimization of LNPs, acceptor photo-reactive biomolecules and optics, this system could be applied to non-invasively actuate neurons deep in the brain.
EDITORIAL: LED light sources (light for the future) LED light sources (light for the future)
NASA Astrophysics Data System (ADS)
Grandjean, N.
2010-09-01
Generating white light from electricity with maximum efficacy has been a long quest since the first incandescent lamp was invented by Edison at the end of the 19th century. Nowadays, semiconductors are making reality the holy grail of converting electrons into photons with 100% efficiency and with colours that can be mixed for white light illumination. The revolution in solid-state lighting (SSL) dates to 1994 when Nakamura reported the first high-brightness blue LED based on GaN semiconductors. Then, white light was produced by simply combining a blue dye with a yellow phosphor. After more than a decade of intensive research the performance of white LEDs is quite impressive, beating by far the luminous efficacy of compact fluorescent lamps. We are likely close to replacing our current lighting devices by SSL lamps. However, there are still technological and fabrication cost issues that could delay large market penetration of white LEDs. Interestingly, SSL may create novel ways of using light that could potentially limit electricity saving. Whatever the impact of SSL, it will be significant on our daily life. The purpose of this special cluster issue is to produce a snapshot of the current situation of SSL from different viewing angles. In an introductory paper, Tsao and co-workers from Sandia National Laboratories, present an energy-economics perspective of SSL considering societal changes and SSL technology evolution. In a second article, Narukawa et al working at Nichia Corporation—the pioneer and still the leading company in SSL—describe the state of the art of current research products. They demonstrate record performance with white LEDs exhibiting luminous efficacy of 183 lm W-1 at high-current injection. Then, a series of topical papers discuss in detail various aspects of the physics and technology of white LEDs Carrier localization in InGaN quantum wells has been considered the key to white LEDs' success despite the huge density of defects. A comprehensive review of the different localization mechanisms and their implication for internal quantum efficiency (IQE) is proposed by Oliver and co-workers from Cambridge University. When discussing IQE in InGaN-based LEDs, the efficiency droop at high-current injection always emerges, which is a major concern for the future of SSL technology. Here, a collaborative work between Samsung and the Gwangju Institute of Science and Technology (Korea) proves that a specific design of the active region can limit this detrimental effect. Once the issue of the IQE is solved, one still has to let the photons out of the chip. Matioli and Weisbuch from the University of California at Santa Barbara introduce the use of photonic crystals (PhCs) to improve light extraction efficiency. They describe different approaches to overcoming the main limitation of LEDs when implementing surface PhCs. The technology of SSL, and in particular of colour rendering, is tackled by Zukauskas et al who studied in detail different white light sources. They show that extreme colour-fidelity indices need to cover the entire spectrum, with a broad-band at 530-610 nm and a component beyond 610 nm. Then, the reliability of GaN-based LEDs is discussed in the paper of Meneghesso and co-workers. The authors consider the most important physical mechanisms that are (i) the degradation of the active layer of LEDs, (ii) the degradation of the package/phosphor system, (iii) the failure of GaN-based LEDs against electrostatic discharge. Finally, GaN LEDs on silicon developed in the group of Egawa at the Nagoya Institute of Technology are presented. This technology could allow a significant decrease in the fabrication cost of white LEDs.
Ultraviolet Radiation in Wound Care: Sterilization and Stimulation
Gupta, Asheesh; Avci, Pinar; Dai, Tianhong; Huang, Ying-Ying; Hamblin, Michael R.
2013-01-01
Significance Wound care is an important area of medicine considering the increasing age of the population who may have diverse comorbidities. Light-based technology comprises a varied set of modalities of increasing relevance to wound care. While low-level laser (or light) therapy and photodynamic therapy both have wide applications in wound care, this review will concentrate on the use of ultraviolet (UV) radiation. Recent Advances UVC (200–280 nm) is highly antimicrobial and can be directly applied to acute wound infections to kill pathogens without unacceptable damage to host tissue. UVC is already widely applied for sterilization of inanimate objects. UVB (280–315 nm) has been directly applied to the wounded tissue to stimulate wound healing, and has been widely used as extracorporeal UV radiation of blood to stimulate the immune system. UVA (315–400 nm) has distinct effects on cell signaling, but has not yet been widely applied to wound care. Critical Issues Penetration of UV light into tissue is limited and optical technology may be employed to extend this limit. UVC and UVB can damage DNA in host cells and this risk must be balanced against beneficial effects. Chronic exposure to UV can be carcinogenic and this must be considered in planning treatments. Future Directions New high-technology UV sources, such as light-emitting diodes, lasers, and microwave-generated UV plasma are becoming available for biomedical applications. Further study of cellular signaling that occurs after UV exposure of tissue will allow the benefits in wound healing to be better defined. PMID:24527357
NASA Astrophysics Data System (ADS)
Zissis, Georges; Haverlag, Marco
2010-06-01
Light sources play an indispensable role in the daily life of any human being. Quality of life, health and urban security related to traffic and crime prevention depend on light and on its quality. In fact, every day approximately 30 billion electric light sources operate worldwide. These electric light sources consume almost 19% of worldwide electricity production. Finding new ways to light lamps is a challenge where the stakes are scientific, technological, economic and environmental. The production of more efficient light sources is a sustainable solution for humanity. There are many opportunities for not only enhancing the efficiency and reliability of lighting systems but also for improving the quality of light as seen by the end user. This is possible through intelligent use of new technologies, deep scientific understanding of the operating principles of light sources and knowledge of the varied human requirements for different types of lighting in different settings. A revolution in the domain of light source technology is on the way: high brightness light emitting diodes arriving in the general lighting market, together with organic LEDs (OLEDs), are producing spectacular advances. However, unlike incandescence, electrical discharge lamps are far from disappearing from the market. In addition, new generations of discharge lamps based on molecular radiators are becoming a reality. There are still many scientific and technological challenges to be raised in this direction. Diagnostics are important for understanding the fundamental mechanisms taking place in the discharge plasma. This understanding is an absolute necessity for system optimization leading to more efficient and high quality light sources. The studied medium is rather complex, but new diagnostic techniques coupled to innovative ideas and powerful tools have been developed in recent years. This cluster issue of seven papers illustrates these efforts. The selected papers cover all domains, from high to low pressure and dielectric barrier lamps, from breakdown to acoustic resonance. Especially in the domain of high pressure lamps, J J Curry shows how coherent and incoherent x-ray scattering can be used as an imaging technique adapted to lamps. J Hirsch et al treat the acoustic resonance phenomenon that seriously limits the frequency domain for high pressure lamp operation. M Jinno et al illustrate a method that allows for measuring Xe buffer gas pressure in Hg-free metal halide lamps for automotive applications. In the domain of low pressure lamps, M Gendre et al investigate the breakdown phase by means of optical and electrical diagnostic tools. The similarity rules used a long time ago for simulating plasma behaviour based on invariants are now serving as diagnostic tools, as shown in the paper by D Michael et al. N Dagang et al show how impurities can be detected in Hg-free electrodeless lamps and more particularly in dielectric barrier discharges emitting excimer radiation. The quality of light is illustrated by a final example by R Kozakov et al on how to qualify the light output from the lamp with respect to biological effects on humans.
Yoo, Gang Yeol; Jeong, Jae-Seung; Lee, Soyoung; Lee, Youngki; Yoon, Hee Chang; Chu, Van Ben; Park, Gi Soon; Hwang, Yun Jeong; Kim, Woong; Min, Byoung Koun; Do, Young Rag
2017-05-03
There are four prerequisites when applying all types of thin-film solar cells to power-generating window photovoltaics (PVs): high power-generation efficiency, longevity and high durability, semitransparency or partial-light transmittance, and colorful and aesthetic value. Solid-type thin-film Cu(In,Ga)S 2 (CIGS) or Cu(In,Ga)(S,Se) 2 (CIGSSe) PVs nearly meet the first two criteria, making them promising candidates for power-generating window applications if they can transmit light to some degree and generate color with good aesthetic value. In this study, the mechanical scribing process removes 10% of the window CIGSSe thin-film solar cell with vacant line patterns to provide a partial-light-transmitting CIGSSe PV module to meet the third requirement. The last concept of creating distinct colors could be met by the addition of reflectance colors of one-dimensional (1D) photonic crystal (PC) dichroic film on the black part of a partial-light-transmitting CIGSSe PV module. Beautiful violets and blues were created on the cover glass of a black CIGSSe PV module via the addition of 1D PC blue-mirror-yellow-pass dichroic film to improve the aesthetic value of the outside appearance. As a general result from the low external quantum efficiency (EQE) and absorption of CIGSSe PVs below a wavelength of 400 nm, the harvesting efficiency and short-circuit photocurrent of CIGSSe PVs were reduced by only ∼10% without reducing the open-circuit voltage (V OC ) because of the reduced overlap between the absorption spectrum of CIGSSe PV and the reflectance spectrum of the 1D PC blue-mirror-yellow-pass dichroic film. The combined technology of partial-vacancy-scribed CIGSSe PV modules and blue 1D PC dichroic film can provide a simple strategy to be applied to violet/blue power-generating window applications, as such a strategy can improve the transparency and aesthetic value without significantly sacrificing the harvesting efficiency of the CIGSSe PV modules.
Perspectives of 30 English Patients on Call Light Technology, Eloquence Revisited.
Montie, Mary; Shuman, Clayton; Galinato, Jose; Patak, Lance; Titler, Marita
2018-01-01
Call light technology is important because it serves as a direct link for patients to get their healthcare needs fulfilled by their healthcare providers. As primary users of call light technology, patient perspectives are important and warranted. Despite this fact, there is a lack of published literature regarding patient perspectives and call light technology. The present study examined a technologically advanced call light system (Eloquence) by incorporating 30 patient participants' perspectives regarding its usefulness, effectiveness, and appropriateness gathered from individual interviews. Using qualitative descriptive research methods, five major themes and multiple minor themes emerged from the data.
Advanced Technology Large-Aperture Space Telescope: Science Drivers and Technology Developments
NASA Technical Reports Server (NTRS)
Postman, Marc; Brown, Tom; Sembach, Kenneth; Glavallsco, Mauro; Traub, Wesley; Stapelfeldt, Karl; Calzetti, Daniela; Oegerle, William; Rich, R. Michael; Stahl, H. Philip;
2012-01-01
The Advanced Technology Large-Aperture Space Telescope (ATLAST) is a concept for an 8- to 16-m ultraviolet optical near Infrared space observatory for launch in the 2025 to 2030 era. ATLAST will allow astronomers to answer fundamental questions at the forefront of modern astrophysics, including: Is there life elsewhere in the Galaxy? We present a range of science drivers and the resulting performance requirements for ATLAST (8- to 16-marcsec angular resolution, diffraction limited imaging at 0.5 micron wavelength, minimum collecting area of 45 sq m, high sensitivity to light wavelengths from 0.1 to 2.4 micron, high stability in wavefront sensing and control). We also discuss the priorities for technology development needed to enable the construction of ATLAST for a cost that is comparable to that of current generation observatory-class space missions.
PACS storage technology update: holographic storage.
Colang, John E; Johnston, James N
2006-01-01
This paper focuses on the emerging technology of holographic storage and its effect on picture archiving and communication systems (PACS). A review of the emerging technology is presented, which includes a high level description of holographic drives and the associated substrate media, the laser and optical technology, and the spatial light modulator. The potential advantages and disadvantages of holographic drive and storage technology are evaluated. PACS administrators face myriad complex and expensive storage solutions and selecting an appropriate system is time-consuming and costly. Storage technology may become obsolete quickly because of the exponential nature of the advances in digital storage media. Holographic storage may turn out to be a low cost, high speed, high volume storage solution of the future; however, data is inconclusive at this early stage of the technology lifecycle. Despite the current lack of quantitative data to support the hypothesis that holographic technology will have a significant effect on PACS and standards of practice, it seems likely from the current information that holographic technology will generate significant efficiencies. This paper assumes the reader has a fundamental understanding of PACS technology.
Full resolution hologram-like autostereoscopic display
NASA Technical Reports Server (NTRS)
Eichenlaub, Jesse B.; Hutchins, Jamie
1995-01-01
Under this program, Dimension Technologies Inc. (DTI) developed a prototype display that uses a proprietary illumination technique to create autostereoscopic hologram-like full resolution images on an LCD operating at 180 fps. The resulting 3D image possesses a resolution equal to that of the LCD along with properties normally associated with holograms, including change of perspective with observer position and lack of viewing position restrictions. Furthermore, this autostereoscopic technique eliminates the need to wear special glasses to achieve the parallax effect. Under the program a prototype display was developed which demonstrates the hologram-like full resolution concept. To implement such a system, DTI explored various concept designs and enabling technologies required to support those designs. Specifically required were: a parallax illumination system with sufficient brightness and control; an LCD with rapid address and pixel response; and an interface to an image generation system for creation of computer graphics. Of the possible parallax illumination system designs, we chose a design which utilizes an array of fluorescent lamps. This system creates six sets of illumination areas to be imaged behind an LCD. This controlled illumination array is interfaced to a lenticular lens assembly which images the light segments into thin vertical light lines to achieve the parallax effect. This light line formation is the foundation of DTI's autostereoscopic technique. The David Sarnoff Research Center (Sarnoff) was subcontracted to develop an LCD that would operate with a fast scan rate and pixel response. Sarnoff chose a surface mode cell technique and produced the world's first large area pi-cell active matrix TFT LCD. The device provided adequate performance to evaluate five different perspective stereo viewing zones. A Silicon Graphics' Iris Indigo system was used for image generation which allowed for static and dynamic multiple perspective image rendering. During the development of the prototype display, we identified many critical issues associated with implementing such a technology. Testing and evaluation enabled us to prove that this illumination technique provides autostereoscopic 3D multi perspective images with a wide range of view, smooth transition, and flickerless operation given suitable enabling technologies.
NASA Astrophysics Data System (ADS)
Whelan, Harry T.; Houle, John M.; Bajic, Dawn M.; Schmidt, Meic H.; Reichert, Kenneth W.; Meyer, Glenn A.
1998-01-01
Photodynamic therapy (PDT) is a cancer treatment modality that recently has been applied as adjuvant therapy for brain tumors. PDT consists of intravenously injecting a photosensitizer, which preferentially accumulates in tumor cells, into a patient and then activating the photosensitizer with a light source. This results in free radical generation followed by cell death. The development of more effective light sources for PDT of brain tumors has been facilitated by applications of space light-emitting diode array technology; thus permitting deeper tumor penetration of light and use of better photosensitizers. Currently, the most commonly used photosensitizer for brain tumor PDT is Photofrin®. Photofrin® is a heterogeneous mixture of compounds derived from hematoporphyrin. Photofrin® is activated with a 630 nm laser light and does destroy tumor cells in animal models and humans. However, treatment failure does occur using this method. Most investigators attribute this failure to the limited penetration of brain tissue by a 630 nm laser light and to the fact that Photofrin® has only a minor absorption peak at 630 nm, meaning that only a small fraction of the chemical is activated. Benzoporphyrin Derivative Monoacid Ring A (BPD) is a new, second generation photosensitizer that can potentially improve PDT for brain tumors. BPD has a major absorption peak at 690 nm, which gives it two distinct advantages over Photofrin®. First, longer wavelengths of light penetrate brain tissue more easily so that larger tumors could be treated, and second, the major absorption peak means that a larger fraction of the drug is activated upon exposure to light. In the first part of this project we have studied the tumoricidal effects of BPD in vitro using 2A9 canine glioma and U373 human glioblastoma cell cultures. Using light emitting diodes (LED) with a peak emission of 688 nm as a light source, cell kill of up to 86 percent was measured in these cell lines by tumor DNA synthesis reduction. The effectiveness of BPD against tumor cells in vitro thus established, we have taken the first step toward determining its effectiveness in vivo. The second part of this project consisted of experiments performed to determine the maximum tolerated dose (MTD) of both BPD and LED light. At a light dose of 100 J/cm2, skin damage and neurotoxicity were seen at a BPD dose of 1.0 mg/kg, but not at a dose of 0.75 mg/kg. When BPD remained constant at 0.75 mg/kg, skin damage was seen at light dosages of 125 J/cm2, 150 J/cm2 and 175 J/cm2. One dog also died at a light dose of 175 J/cm2. Further studies will be needed to determine the effectiveness of BPD against tumor cells in vivo.
Concentrated solar power in the built environment
NASA Astrophysics Data System (ADS)
Montenon, Alaric C.; Fylaktos, Nestor; Montagnino, Fabio; Paredes, Filippo; Papanicolas, Costas N.
2017-06-01
Solar concentration systems are usually deployed in large open spaces for electricity generation; they are rarely used to address the pressing energy needs of the built environment sector. Fresnel technology offers interesting and challenging CSP energy pathways suitable for the built environment, due to its relatively light weight (<30 kg.m-2) and low windage. The Cyprus Institute (CyI) and Consorzio ARCA are cooperating in such a research program; we report here the construction and integration of a 71kW Fresnel CSP system into the HVAC (Heating, Ventilation, and Air Conditioning) system of a recently constructed office & laboratory building, the Novel Technologies Laboratory (NTL). The multi-generative system will support cooling, heating and hot water production feeding the system of the NTL building, as a demonstration project, part of the STS-MED program (Small Scale Thermal Solar District Units for Mediterranean Communities) financed by the European Commission under the European Neighbourhood and Partnership Instrument (ENPI), CBCMED program.
A multi-channel tunable source for atomic sensors
NASA Astrophysics Data System (ADS)
Bigelow, Matthew S.; Roberts, Tony D.; McNeil, Shirley A.; Hawthorne, Todd; Battle, Phil
2015-09-01
We have designed and completed initial testing on a laser source suitable for atomic interferometry from compact, robust, integrated components. Our design is enabled by capitalizing on robust, well-commercialized, low-noise telecom components with high reliability and declining costs which will help to drive the widespread deployment of this system. The key innovation is the combination of current telecom-based fiber laser and modulator technology with periodicallypoled waveguide technology to produce tunable laser light at rubidium D1 and D2 wavelengths (and expandable to other alkalis) using second harmonic generation (SHG). Unlike direct-diode sources, this source is immune to feedback at the Rb line eliminating the need for bulky high-power isolators in the system. In addition, the source has GHz-level frequency agility and in our experiments was found to only be limited by the agility of our RF generator. As a proof-of principle, the source was scanned through the Doppler-broadened Rb D2 absorption line. With this technology, multiple channels can be independently tuned to produce the fields needed for addressing atomic states in atom interferometers and clocks. Thus, this technology could be useful in the development cold-atom inertial sensors and gyroscopes.
Technologies for Upgrading Light Water Reactor Outlet Temperature
DOE Office of Scientific and Technical Information (OSTI.GOV)
Daniel S. Wendt; Piyush Sabharwall; Vivek Utgikar
Nuclear energy could potentially be utilized in hybrid energy systems to produce synthetic fuels and feedstocks from indigenous carbon sources such as coal and biomass. First generation nuclear hybrid energy system (NHES) technology will most likely be based on conventional light water reactors (LWRs). However, these LWRs provide thermal energy at temperatures of approximately 300°C, while the desired temperatures for many chemical processes are much higher. In order to realize the benefits of nuclear hybrid energy systems with the current LWR reactor fleets, selection and development of a complimentary temperature upgrading technology is necessary. This paper provides an initial assessmentmore » of technologies that may be well suited toward LWR outlet temperature upgrading for powering elevated temperature industrial and chemical processes during periods of off-peak power demand. Chemical heat transformers (CHTs) are a technology with the potential to meet LWR temperature upgrading requirements for NHESs. CHTs utilize chemical heat of reaction to change the temperature at which selected heat sources supply or consume thermal energy. CHTs could directly utilize LWR heat output without intermediate mechanical or electrical power conversion operations and the associated thermodynamic losses. CHT thermal characteristics are determined by selection of the chemical working pair and operating conditions. This paper discusses the chemical working pairs applicable to LWR outlet temperature upgrading and the CHT operating conditions required for providing process heat in NHES applications.« less
NASA Astrophysics Data System (ADS)
Agus, Viviana; Di Silvio, Alberto; Rolland, Jean Francois; Mondini, Anna; Tremolada, Sara; Montag, Katharina; Scarabottolo, Lia; Redaelli, Loredana; Lohmer, Stefan
2015-03-01
The use of light-activated proteins represents a powerful tool to control biological processes with high spatial and temporal precision. These so called "optogenetic" technologies have been successfully validated in many recombinant systems, and have been widely applied to the study of cellular mechanisms in intact tissues or behaving animals; to do that, complex, high-intensity, often home-made instrumentations were developed to achieve the optimal power and precision of light stimulation. In our study we sought to determine if this optical modulation can be obtained also in a miniaturized format, such as a 384-well plate, using the instrumentations normally dedicated to fluorescence analysis in High Throughput Screening (HTS) activities, such as for example the FLIPR (Fluorometric Imaging Plate Reader) instrument. We successfully generated optogenetic assays for the study of different ion channel targets: the CaV1.3 calcium channel was modulated by the light-activated Channelrhodopsin-2, the HCN2 cyclic nucleotide gated (CNG) channel was modulated by the light activated bPAC adenylyl cyclase, and finally the genetically encoded voltage indicator ArcLight was efficiently used to measure potassium, sodium or chloride channel activity. Our results showed that stable, robust and miniaturized cellular assays can be developed using different optogenetic tools, and efficiently modulated by the FLIPR instrument LEDs in a 384-well format. The spatial and temporal resolution delivered by this technology might enormously advantage the early stages of drug discovery, leading to the identification of more physiological and effective drug molecules.
Quantum cryptography over underground optical fibers
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hughes, R.J.; Luther, G.G.; Morgan, G.L.
1996-05-01
Quantum cryptography is an emerging technology in which two parties may simultaneously generated shared, secret cryptographic key material using the transmission of quantum states of light whose security is based on the inviolability of the laws of quantum mechanics. An adversary can neither successfully tap the key transmissions, nor evade detection, owing to Heisenberg`s uncertainty principle. In this paper the authors describe the theory of quantum cryptography, and the most recent results from their experimental system with which they are generating key material over 14-km of underground optical fiber. These results show that optical-fiber based quantum cryptography could allow secure,more » real-time key generation over ``open`` multi-km node-to-node optical fiber communications links between secure ``islands.``« less
High-quality quantum-dot-based full-color display technology by pulsed spray method
NASA Astrophysics Data System (ADS)
Chen, Kuo-Ju; Chen, Hsin-Chu; Tsai, Kai-An; Lin, Chien-Chung; Tsai, Hsin-Han; Chien, Shih-Hsuan; Cheng, Bo-Siao; Hsu, Yung-Jung; Shih, Min-Hsiung; Kuo, Hao-Chung
2013-03-01
We fabricated the colloidal quantum-dot light-emitting diodes (QDLEDs) with the HfO2/SiO2-distributed Bragg reflector (DBR) structure using a pulsed spray coating method. Moreover, pixelated RGB arrays, 2-in. wafer-scale white light emission, and an integrated small footprint white light device were demonstrated. The experimental results showed that the intensity of red, blue, and green (RGB) emissions exhibited considerable enhancement because of the high reflectivity in the UV region by the DBR structure, which subsequently increased the use in the UV optical pumping of RGB QDs. In this experiment, a pulsed spray coating method was crucial in providing uniform RGB layers, and the polydimethylsiloxane (PDMS) film was used as the interface layer between each RGB color to avoid crosscontamination and self-assembly of QDs. Furthermore, the chromaticity coordinates of QDLEDs with the DBR structure remained constant under various pumping powers in the large area sample, whereas a larger shift toward high color temperatures was observed in the integrated device. The resulting color gamut of the proposed QDLEDs covered an area 1.2 times larger than that of the NTSC standard, which is favorable for the next generation of high-quality display technology.
Optical Characterization of Light-Bending Mechanisms in Photonic Crystals with Simple Cubic Symmetry
NASA Astrophysics Data System (ADS)
Frey, Brian James
For much of Earth's history, light was reputed to be an intangible, intractable, and transient quantity, but our understanding of light has since been revolutionized. The flow of electromagnetic energy through space can today be manipulated with a degree of precision and control once only dreamed of; rapidly developing technologies can create, guide, bend, and detect light to produce useful energy and information. One field where these technologies are most relevant is the field of light trapping, which concerns the harvesting of incident photons within a limited space by scattering, slowing, or otherwise prolonging and enhancing their interaction with matter. Over the past few decades, a class of materials, called photonic crystals (PCs), has emerged that is ideally suited for this task. This is because their wavelength-scale periodicity in one, two, or three dimensions can be designed to alter the dispersion relation and photonic density-of-states in a controllable manner. In this work, a TiO2 simple cubic PC with high dielectric contrast ( > 4:1) is fabricated with a lattice constant of 450 nm, and a newly discovered light-trapping mechanism is demonstrated, which bends light by 90 degrees and enhances optical absorption by one to two orders-of-magnitude over that in a reference film of the same thickness. It is shown that, for wavelengths from 450-950 nm, the achievable enhancement factor for this structure surpasses the theoretical limit of 4n2 derived under the assumption of ergodic system by multiple times. These results derive directly from the symmetry of the simple cubic lattice and are fundamental in nature, not depending on the material used or on the method of fabrication. The light trapping capability of these PCs has straight-forward applications that would be useful in a variety of areas where increased light-matter interaction is desirable, such as white-light generation, thin-film solar cells, photocatalytic pollutant degradation and hydrogen fuel production, and chemical sensing.
A retrospective analysis of funding and focus in US advanced fission innovation
NASA Astrophysics Data System (ADS)
Abdulla, A.; Ford, M. J.; Morgan, M. G.; Victor, D. G.
2017-08-01
Deep decarbonization of the global energy system will require large investments in energy innovation and the deployment of new technologies. While many studies have focused on the expenditure that will be needed, here we focus on how government has spent public sector resources on innovation for a key carbon-free technology: advanced nuclear. We focus on nuclear power because it has been contributing almost 20% of total US electric generation, and because the US program in this area has historically been the world’s leading effort. Using extensive data acquired through the Freedom of Information Act, we reconstruct the budget history of the Department of Energy’s program to develop advanced, non-light water nuclear reactors. Our analysis shows that—despite spending 2 billion since the late 1990s—no advanced design is ready for deployment. Even if the program had been well designed, it still would have been insufficient to demonstrate even one non-light water technology. It has violated much of the wisdom about the effective execution of innovative programs: annual funding varies fourfold, priorities are ephemeral, incumbent technologies and fuels are prized over innovation, and infrastructure spending consumes half the budget. Absent substantial changes, the possibility of US-designed advanced reactors playing a role in decarbonization by mid-century is low.
U.S. Department of Energy Accident Resistant SiC Clad Nuclear Fuel Development
DOE Office of Scientific and Technical Information (OSTI.GOV)
George W. Griffith
2011-10-01
A significant effort is being placed on silicon carbide ceramic matrix composite (SiC CMC) nuclear fuel cladding by Light Water Reactor Sustainability (LWRS) Advanced Light Water Reactor Nuclear Fuels Pathway. The intent of this work is to invest in a high-risk, high-reward technology that can be introduced in a relatively short time. The LWRS goal is to demonstrate successful advanced fuels technology that suitable for commercial development to support nuclear relicensing. Ceramic matrix composites are an established non-nuclear technology that utilizes ceramic fibers embedded in a ceramic matrix. A thin interfacial layer between the fibers and the matrix allows formore » ductile behavior. The SiC CMC has relatively high strength at high reactor accident temperatures when compared to metallic cladding. SiC also has a very low chemical reactivity and doesn't react exothermically with the reactor cooling water. The radiation behavior of SiC has also been studied extensively as structural fusion system components. The SiC CMC technology is in the early stages of development and will need to mature before confidence in the developed designs can created. The advanced SiC CMC materials do offer the potential for greatly improved safety because of their high temperature strength, chemical stability and reduced hydrogen generation.« less
Strategies to Achieve High-Performance White Organic Light-Emitting Diodes
Zhang, Lirong; Li, Xiang-Long; Luo, Dongxiang; Xiao, Peng; Xiao, Wenping; Song, Yuhong; Ang, Qinshu; Liu, Baiquan
2017-01-01
As one of the most promising technologies for next-generation lighting and displays, white organic light-emitting diodes (WOLEDs) have received enormous worldwide interest due to their outstanding properties, including high efficiency, bright luminance, wide viewing angle, fast switching, lower power consumption, ultralight and ultrathin characteristics, and flexibility. In this invited review, the main parameters which are used to characterize the performance of WOLEDs are introduced. Subsequently, the state-of-the-art strategies to achieve high-performance WOLEDs in recent years are summarized. Specifically, the manipulation of charges and excitons distribution in the four types of WOLEDs (fluorescent WOLEDs, phosphorescent WOLEDs, thermally activated delayed fluorescent WOLEDs, and fluorescent/phosphorescent hybrid WOLEDs) are comprehensively highlighted. Moreover, doping-free WOLEDs are described. Finally, issues and ways to further enhance the performance of WOLEDs are briefly clarified. PMID:29194426
Material platforms for spin-based photonic quantum technologies
NASA Astrophysics Data System (ADS)
Atatüre, Mete; Englund, Dirk; Vamivakas, Nick; Lee, Sang-Yun; Wrachtrup, Joerg
2018-05-01
A central goal in quantum optics and quantum information science is the development of quantum networks to generate entanglement between distributed quantum memories. Experimental progress relies on the quality and efficiency of the light-matter quantum interface connecting the quantum states of photons to internal states of quantum emitters. Quantum emitters in solids, which have properties resembling those of atoms and ions, offer an opportunity for realizing light-matter quantum interfaces in scalable and compact hardware. These quantum emitters require a material platform that enables stable spin and optical properties, as well as a robust manufacturing of quantum photonic circuits. Because no emitter system is yet perfect and different applications may require different properties, several light-matter quantum interfaces are being developed in various platforms. This Review highlights the progress in three leading material platforms: diamond, silicon carbide and atomically thin semiconductors.
Long-lived efficient delayed fluorescence organic light-emitting diodes using n-type hosts.
Cui, Lin-Song; Ruan, Shi-Bin; Bencheikh, Fatima; Nagata, Ryo; Zhang, Lei; Inada, Ko; Nakanotani, Hajime; Liao, Liang-Sheng; Adachi, Chihaya
2017-12-21
Organic light-emitting diodes have become a mainstream display technology because of their desirable features. Third-generation electroluminescent devices that emit light through a mechanism called thermally activated delayed fluorescence are currently garnering much attention. However, unsatisfactory device stability is still an unresolved issue in this field. Here we demonstrate that electron-transporting n-type hosts, which typically include an acceptor moiety in their chemical structure, have the intrinsic ability to balance the charge fluxes and broaden the recombination zone in delayed fluorescence organic electroluminescent devices, while at the same time preventing the formation of high-energy excitons. The n-type hosts lengthen the lifetimes of green and blue delayed fluorescence devices by > 30 and 1000 times, respectively. Our results indicate that n-type hosts are suitable to realize stable delayed fluorescence organic electroluminescent devices.
Advanced sensors and instrumentation
NASA Technical Reports Server (NTRS)
Calloway, Raymond S.; Zimmerman, Joe E.; Douglas, Kevin R.; Morrison, Rusty
1990-01-01
NASA is currently investigating the readiness of Advanced Sensors and Instrumentation to meet the requirements of new initiatives in space. The following technical objectives and technologies are briefly discussed: smart and nonintrusive sensors; onboard signal and data processing; high capacity and rate adaptive data acquisition systems; onboard computing; high capacity and rate onboard storage; efficient onboard data distribution; high capacity telemetry; ground and flight test support instrumentation; power distribution; and workstations, video/lighting. The requirements for high fidelity data (accuracy, frequency, quantity, spatial resolution) in hostile environments will continue to push the technology developers and users to extend the performance of their products and to develop new generations.
A design of LED adaptive dimming lighting system based on incremental PID controller
NASA Astrophysics Data System (ADS)
He, Xiangyan; Xiao, Zexin; He, Shaojia
2010-11-01
As a new generation energy-saving lighting source, LED is applied widely in various technology and industry fields. The requirement of its adaptive lighting technology is more and more rigorous, especially in the automatic on-line detecting system. In this paper, a closed loop feedback LED adaptive dimming lighting system based on incremental PID controller is designed, which consists of MEGA16 chip as a Micro-controller Unit (MCU), the ambient light sensor BH1750 chip with Inter-Integrated Circuit (I2C), and constant-current driving circuit. A given value of light intensity required for the on-line detecting environment need to be saved to the register of MCU. The optical intensity, detected by BH1750 chip in real time, is converted to digital signal by AD converter of the BH1750 chip, and then transmitted to MEGA16 chip through I2C serial bus. Since the variation law of light intensity in the on-line detecting environment is usually not easy to be established, incremental Proportional-Integral-Differential (PID) algorithm is applied in this system. Control variable obtained by the incremental PID determines duty cycle of Pulse-Width Modulation (PWM). Consequently, LED's forward current is adjusted by PWM, and the luminous intensity of the detection environment is stabilized by self-adaptation. The coefficients of incremental PID are obtained respectively after experiments. Compared with the traditional LED dimming system, it has advantages of anti-interference, simple construction, fast response, and high stability by the use of incremental PID algorithm and BH1750 chip with I2C serial bus. Therefore, it is suitable for the adaptive on-line detecting applications.
Xie, Ming-Hua; Shao, Rong; Xi, Xin-Guo; Hou, Gui-Hua; Guan, Rong-Feng; Dong, Peng-Yu; Zhang, Qin-Fang; Yang, Xiu-Li
2017-03-17
A 3D metal-organic framework (ADA-Cd=[Cd 2 L 2 (DMF) 2 ]⋅3 H 2 O where H 2 L is (2E,2'E)-3,3'-(anthracene-9,10-diyl)diacrylic acid) constructed from diacrylate substituted anthracene, sharing structural characteristics with some frequently employed anthraquinone-type dye sensitizers, was introduced as an effective sensitizer for anatase TiO 2 to achieve enhanced visible light photocatalytic performance. A facile mechanical mixing procedure was adopted to prepare the co-catalyst denoted as ADA-Cd/TiO 2 , which showed enhanced photodegradation ability, as well as sustainability, towards several dyes under visible light irradiation. Mechanistic studies revealed that ADA-Cd acted as the antenna to harvest visible light energy, generating excited electrons, which were injected to the conduction band (CB) of TiO 2 , facilitating the separation efficiency of charge carriers. As suggested by the results of control experiments, combined with the corresponding redox potential of possible oxidative species, . O 2 - , generated from the oxygen of ambient air at the CB of TiO 2 was believed to play a dominant role over . OH and h + . UV/Vis and photoluminescence technologies were adopted to monitor the generation of . O 2 - and . OH, respectively. This work presents a facile strategy to achieve a visible light photocatalyst with enhanced catalytic activity and sustainability; the simplicity, efficiency, and stability of this strategy may provide a promising way to achieve environmental remediation. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Broadband sensitized photon up-conversion at subsolar irradiance (Conference Presentation)
NASA Astrophysics Data System (ADS)
Pedrini, Jacopo; Monguzzi, Angelo; Meinardi, Francesco
2016-09-01
A crucial limit of solar devices is their inability to harvest the full solar spectrum. Currently, sensitized up-conversion based on triplet-tripled annihilation (STTA-UC) in bi-component organic systems is the most promising technique to recover sub-bandgap photons, showing good efficiencies also at excitation intensities comparable to the solar irradiance. In STTA-UC, high-energy light is generated through annihilation of metastable triplet states of molecules acting as emitters, which are populated via resonant energy transfer from a light-harvesting sensitizer. However, suitable sensitizers show narrow absorption bands, limiting the fraction of recoverable photons, therefore preventing the application of STTA-UC to real-world devices. Here we demonstrate how to overcome the described limit by using multiple sensitizers that work cooperatively to broaden the overall system absorption band. This is obtained using an additional sensitizer that transfers the extra harvested energy to the main one (sensitization of the sensitizer), or a set of properly designed complementary absorbing sensitizers all able to excite simultaneously the same emitter (multi-sensitizers). In both cases STTA-UC performances result strongly enhanced compared to the corresponding mono-sensitizer system, increasing the up-converted light intensity generated at AM 1.5 up to two times. Remarkably, by coupling our light converters to a DSSC we prove its operation by exploiting exclusively sub-bandgap photons. A detailed modeling of the photophysical processes involved in these complex systems allows us to draw the guidelines for the design of the next generation STTA-UC materials, encouraging their application to photovoltaic technologies.
Kovalev, S; Green, B; Golz, T; Maehrlein, S; Stojanovic, N; Fisher, A S; Kampfrath, T; Gensch, M
2017-03-01
Understanding dynamics on ultrafast timescales enables unique and new insights into important processes in the materials and life sciences. In this respect, the fundamental pump-probe approach based on ultra-short photon pulses aims at the creation of stroboscopic movies. Performing such experiments at one of the many recently established accelerator-based 4th-generation light sources such as free-electron lasers or superradiant THz sources allows an enormous widening of the accessible parameter space for the excitation and/or probing light pulses. Compared to table-top devices, critical issues of this type of experiment are fluctuations of the timing between the accelerator and external laser systems and intensity instabilities of the accelerator-based photon sources. Existing solutions have so far been only demonstrated at low repetition rates and/or achieved a limited dynamic range in comparison to table-top experiments, while the 4th generation of accelerator-based light sources is based on superconducting radio-frequency technology, which enables operation at MHz or even GHz repetition rates. In this article, we present the successful demonstration of ultra-fast accelerator-laser pump-probe experiments performed at an unprecedentedly high repetition rate in the few-hundred-kHz regime and with a currently achievable optimal time resolution of 13 fs (rms). Our scheme, based on the pulse-resolved detection of multiple beam parameters relevant for the experiment, allows us to achieve an excellent sensitivity in real-world ultra-fast experiments, as demonstrated for the example of THz-field-driven coherent spin precession.
Monolayer Transition Metal Dichalcogenides as Light Sources.
Pu, Jiang; Takenobu, Taishi
2018-06-13
Reducing the dimensions of materials is one of the key approaches to discovering novel optical phenomena. The recent emergence of 2D transition metal dichalcogenides (TMDCs) has provided a promising platform for exploring new optoelectronic device applications, with their tunable electronic properties, structural controllability, and unique spin valley-coupled systems. This progress report provides an overview of recent advances in TMDC-based light-emitting devices discussed from several aspects in terms of device concepts, material designs, device fabrication, and their diverse functionalities. First, the advantages of TMDCs used in light-emitting devices and their possible functionalities are presented. Second, conventional approaches for fabricating TMDC light-emitting devices are emphasized, followed by introducing a newly established, versatile method for generating light emission in TMDCs. Third, current growing technologies for heterostructure fabrication, in which distinct TMDCs are vertically stacked or laterally stitched, are explained as a possible means for designing high-performance light-emitting devices. Finally, utilizing the topological features of TMDCs, the challenges for controlling circularly polarized light emission and its device applications are discussed from both theoretical and experimental points of view. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Growth and development of Arabidopsis thaliana under single-wavelength red and blue laser light.
Ooi, Amanda; Wong, Aloysius; Ng, Tien Khee; Marondedze, Claudius; Gehring, Christoph; Ooi, Boon S
2016-09-23
Indoor horticulture offers a sensible solution for sustainable food production and is becoming increasingly widespread. However, it incurs high energy and cost due to the use of artificial lighting such as high-pressure sodium lamps, fluorescent light or increasingly, the light-emitting diodes (LEDs). The energy efficiency and light quality of currently available horticultural lighting is suboptimal, and therefore less than ideal for sustainable and cost-effective large-scale plant production. Here, we demonstrate the use of high-powered single-wavelength lasers for indoor horticulture. They are highly energy-efficient and can be remotely guided to the site of plant growth, thus reducing on-site heat accumulation. Furthermore, laser beams can be tailored to match the absorption profiles of different plant species. We have developed a prototype laser growth chamber and demonstrate that plants grown under laser illumination can complete a full growth cycle from seed to seed with phenotypes resembling those of plants grown under LEDs reported previously. Importantly, the plants have lower expression of proteins diagnostic for light and radiation stress. The phenotypical, biochemical and proteome data show that the single-wavelength laser light is suitable for plant growth and therefore, potentially able to unlock the advantages of this next generation lighting technology for highly energy-efficient horticulture.
Growth and development of Arabidopsis thaliana under single-wavelength red and blue laser light
Ooi, Amanda; Wong, Aloysius; Ng, Tien Khee; Marondedze, Claudius; Gehring, Christoph; Ooi, Boon S.
2016-01-01
Indoor horticulture offers a sensible solution for sustainable food production and is becoming increasingly widespread. However, it incurs high energy and cost due to the use of artificial lighting such as high-pressure sodium lamps, fluorescent light or increasingly, the light-emitting diodes (LEDs). The energy efficiency and light quality of currently available horticultural lighting is suboptimal, and therefore less than ideal for sustainable and cost-effective large-scale plant production. Here, we demonstrate the use of high-powered single-wavelength lasers for indoor horticulture. They are highly energy-efficient and can be remotely guided to the site of plant growth, thus reducing on-site heat accumulation. Furthermore, laser beams can be tailored to match the absorption profiles of different plant species. We have developed a prototype laser growth chamber and demonstrate that plants grown under laser illumination can complete a full growth cycle from seed to seed with phenotypes resembling those of plants grown under LEDs reported previously. Importantly, the plants have lower expression of proteins diagnostic for light and radiation stress. The phenotypical, biochemical and proteome data show that the single-wavelength laser light is suitable for plant growth and therefore, potentially able to unlock the advantages of this next generation lighting technology for highly energy-efficient horticulture. PMID:27659906
Multiple-target tracking implementation in the ebCMOS camera system: the LUSIPHER prototype
NASA Astrophysics Data System (ADS)
Doan, Quang Tuyen; Barbier, Remi; Dominjon, Agnes; Cajgfinger, Thomas; Guerin, Cyrille
2012-06-01
The domain of the low light imaging systems progresses very fast, thanks to detection and electronic multiplication technology evolution, such as the emCCD (electron multiplying CCD) or the ebCMOS (electron bombarded CMOS). We present an ebCMOS camera system that is able to track every 2 ms more than 2000 targets with a mean number of photons per target lower than two. The point light sources (targets) are spots generated by a microlens array (Shack-Hartmann) used in adaptive optics. The Multiple-Target-Tracking designed and implemented on a rugged workstation is described. The results and the performances of the system on the identification and tracking are presented and discussed.
Photon Science for Renewable Energy
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hussain, Zahid; Tamura, Lori; Padmore, Howard
2010-03-31
Our current fossil-fuel-based system is causing potentially catastrophic changes to our planet. The quest for renewable, nonpolluting sources of energy requires us to understand, predict, and ultimately control matter and energy at the electronic, atomic, and molecular levels. Light-source facilities - the synchrotrons of today and the next-generation light sources of tomorrow - are the scientific tools of choice for exploring the electronic and atomic structure of matter. As such, these photon-science facilities are uniquely positioned to jump-start a global revolution in renewable and carbonneutral energy technologies. In these pages, we outline and illustrate through examples from our nation's lightmore » sources possible scientific directions for addressing these profound yet urgent challenges.« less
A study on Aerosol jet printing technology in LED module manufacturing
NASA Astrophysics Data System (ADS)
Rudorfer, Andreas; Tscherner, Martin; Palfinger, Christian; Reil, Frank; Hartmann, Paul; Seferis, Ioannis E.; Zych, Eugeniusz; Wenzl, Franz P.
2016-09-01
State of the art fabrication of LED modules based on chip-on-board (COB) technology comprises some shortcomings both with respect to the manufacturing process itself but also with regard to potential sources of failures and manufacturing impreciseness. One promising alternative is additive manufacturing, a technology which has gained a lot of attention during the last years due to its materials and cost saving capabilities. Especially direct-write technologies like Aerosol jet printing have demonstrated advantages compared to other technological approaches when printing high precision layers or high precision electronic circuits on substrates which, as an additional advantage, also can be flexible and 3D shaped. Based on test samples and test structures manufactured by Aerosol jet printing technology, in this context we discuss the potentials of additive manufacturing in various aspects of LED module fabrication, ranging from the deposition of the die-attach material, wire bond replacement by printed electrical connects as well as aspects of high-precision phosphor layer deposition for color conversion and white light generation.
Development of Structural Health Management Technology for Aerospace Vehicles
NASA Technical Reports Server (NTRS)
Prosser, W. H.
2003-01-01
As part of the overall goal of developing Integrated Vehicle Health Management (IVHM) systems for aerospace vehicles, NASA has focused considerable resources on the development of technologies for Structural Health Management (SHM). The motivations for these efforts are to increase the safety and reliability of aerospace structural systems, while at the same time decreasing operating and maintenance costs. Research and development of SHM technologies has been supported under a variety of programs for both aircraft and spacecraft including the Space Launch Initiative, X-33, Next Generation Launch Technology, and Aviation Safety Program. The major focus of much of the research to date has been on the development and testing of sensor technologies. A wide range of sensor technologies are under consideration including fiber-optic sensors, active and passive acoustic sensors, electromagnetic sensors, wireless sensing systems, MEMS, and nanosensors. Because of their numerous advantages for aerospace applications, most notably being extremely light weight, fiber-optic sensors are one of the leading candidates and have received considerable attention.
NASA Programs in Advanced Sensors and Measurement Technology for Aeronautical Applications
NASA Technical Reports Server (NTRS)
Conway, Bruce A.
2004-01-01
There are many challenges facing designers and operators of our next-generation aircraft in meeting the demands for efficiency, safety, and reliability which are will be imposed. This paper discusses aeronautical sensor requirements for a number of research and applications areas pertinent to the demands listed above. A brief overview will be given of aeronautical research measurements, along with a discussion of requirements for advanced technology. Also included will be descriptions of emerging sensors and instrumentation technology which may be exploited for enhanced research and operational capabilities. Finally, renewed emphasis of the National Aeronautics and Space Administration in advanced sensor and instrumentation technology development will be discussed, including project of technology advances over the next 5 years. Emphasis on NASA efforts to more actively advance the state-of-the-art in sensors and measurement techniques is timely in light of exciting new opportunities in airspace development and operation. An up-to-date summary of the measurement technology programs being established to respond to these opportunities is provided.
2006-04-15
was amplified by injection locking of a high power diode laser and further amplified to -300 mW with a semiconductor optical amplifier. This light...amplifiers at 793nm, cascaded injection locked amplifiers at 793nm, and frequency chirped lasers at 793nm. 15. SUBJECT TERMS Optical Coherent Transients...injection- locking for broadband optical signal amplification ................. 34 2.10. Tapered semiconductor optical amplifier
Photoaligning and photopatterning technology: applications in displays and photonics
NASA Astrophysics Data System (ADS)
Chigrinov, Vladimir
2016-03-01
The advantages of LC photoalignment technology in comparison with common "rubbing" alignment methods tend to the continuation of the research in this field. Almost all the criteria of perfect LC alignment are met in case of azo-dye layers. Nowadays azo-dye alignment materials can be already used in LCD manufacturing, e.g. for the alignment of monomers in LCP films for new generations of photonics and optics devices. Recently the new application of photoaligned technology for the tunable LC lenses with a variable focal distance was proposed. New optically rewritable (ORW) liquid crystal display and photonics devices with a light controllable structure may include LC E-paper screens, LC lenses with a variable focal distance etc. Fast ferroelectric liquid crystal devices (FLCD) are achieved through the application of nano-scale photo aligning (PA) layers in FLC cells. The novel photoaligned FLC devices may include field sequential color (FSC) FLC with a high resolution, high brightness, low power consumption and extended color gamut to be used for PCs, PDAs, switchable goggles, and new generation of switchable 2D/3D LCD TVs, as well as photonics elements.
A novel application for concentrator photovoltaic in the field of agriculture photovoltaics
NASA Astrophysics Data System (ADS)
Liu, Luqing; Guan, Chenggang; Zhang, Fangxin; Li, Ming; Lv, Hui; Liu, Yang; Yao, Peijun; Ingenhoff, Jan; Liu, Wen
2017-09-01
Agriculture photovoltaics is a trend setting area which has already led to a new industrial revolution. Shortage of land in some countries and desertification of land where regular solar panels are deployed are some of the major problems in the photovoltaic industry. Concentrator photovoltaics experienced a decline in applicability after the cost erosion of regular solar panels at the end of the last decade. We demonstrate a novel and unique application for concentrator photovoltaics tackling at a same time the issue of conventional photovoltaics preventing the land being used for agricultural purpose where ever solar panels are installed. We leverage the principle of diffractive and interference technology to split the sun light into transmitted wavelengths necessary for plant growth and reflected wavelengths useful for solar energy generation. The technology has been successfully implemented in field trials and sophisticated scientific studies have been undertaken to evaluate the suitability of this technology for competitive solar power generation and simultaneous high-quality plant growth. The average efficiency of the agriculture photovoltaic system has reached more than 8% and the average efficiency of the CPV system is 6.80%.
Jiang, Qiang; Chen, Bo; Zhang, Kewei; Yang, Ya
2017-12-20
Li-ion batteries are a green energy storage technology with advantages of high energy density, long lifetime, and sustainability, but they cannot generate electric energy by themselves. As a novel energy-harvesting technology, triboelectric nanogenerators (TENGs) are a promising power source for supplying electronic devices, however it is difficult to directly use their high output voltage and low output current. Here, we designed a Ag nanoparticle-based TENG for scavenging wind energy. After including a transformer and a power management circuit into the system, constant output voltages such as 3.6 V and a pulsed current of about 100 mA can be obtained, which can be used to directly light up a light-emitting diode. Furthermore, the produced electric energy can be effectively stored in a WO 3 /LiMn 2 O 4 electrode based Li-ion battery. Our present work provides a new approach to effectively scavenge wind energy and store the obtained electric energy, which is significant for exploring self-charging power units.
Life-finding detector development at NASA GSFC using a custom H4RG test bed
NASA Astrophysics Data System (ADS)
Mosby, Gregory; Rauscher, Bernard; Kutyrev, Alexander
2018-01-01
Chemical species associated with life, called biosignatures, should be visible in exoplanet atmospheres with larger space telescopes. These signals will be faint and require very low noise (~e-) detectors to robustly measure. At NASA Goddard we are developing a single detector H4RG test bed to characterize and identify potential technology developments needed for the next generation's large space telescopes. The vacuum and cryogenic test bed will include near infrared light sources from integrating spheres using a motorized shutter. The detector control and readout will be handled by a Leach controller. Detector cables have been manufactured and test planning has begun. Planned tests include testing minimum read noise capabilities, persistence mitigation strategies using long wavelength light, and measuring intrapixel variation which might affect science goals of future missions. In addition to providing a means to identify areas of improvement in detector technology, we hope to use this test bed to probe some fundamental physics of these infrared arrays.
Functionalized nanostructures for enhanced photocatalytic performance under solar light.
Guo, Liejin; Jing, Dengwei; Liu, Maochang; Chen, Yubin; Shen, Shaohua; Shi, Jinwen; Zhang, Kai
2014-01-01
Photocatalytic hydrogen production from water has been considered to be one of the most promising solar-to-hydrogen conversion technologies. In the last decade, various functionalized nanostructures were designed to address the primary requirements for an efficient photocatalytic generation of hydrogen by using solar energy: visible-light activity, chemical stability, appropriate band-edge characteristics, and potential for low-cost fabrication. Our aim is to present a short review of our recent attempts that center on the above requirements. We begin with a brief introduction of photocatalysts coupling two or more semiconductors, followed by a further discussion of the heterostructures with improved matching of both band structures and crystal lattices. We then elaborate on the heterostructure design of the targeted materials from macroscopic regulation of compositions and phases, to the more precise control at the nanoscale, i.e., materials with the same compositions but different phases with certain band alignment. We conclude this review with perspectives on nanostructure design that might direct future research of this technology.
NASA Astrophysics Data System (ADS)
Liu, Lin; Choi, Seokheun
2017-04-01
Among many energy harvesting techniques with great potential, microbial fuel cell (MFC) technology is arguably the most underdeveloped. Even so, excitement is building, as microorganisms can harvest electrical power from any biodegradable organic source (e.g. wastewater) that is readily available in resource-limited settings. Nevertheless, the requirement for endless introduction of organic matter imposes a limiting factor to this technology, demanding an active feeding system and additional power. Here, we demonstrated self-sustaining bioelectricity generation from a microliter-scale microbial fuel cell (MFC) by using the syntrophic interaction between heterotrophic exoelectrogenic bacteria and phototrophs. The MFC continuously generated light-responsive electricity from the heterotrophic bacterial metabolic respiration with the organic substrates produced by photosynthetic bacteria. Without additional organic fuel, the mixed culture in a 90-μL-chamber MFC generated self-sustained current for more than 13 days, while the heterotrophic culture produced current that decreased dramatically within a few hours. The current from the mixed culture was about 70 times greater than that of the device with only photosynthetic bacteria. The miniaturization provided a short start-up time, a well-controlled environment, and small internal resistance. Those advantages will become the general design platform for micropower generation.
Solar photovoltaics: current state and trends
NASA Astrophysics Data System (ADS)
Milichko, V. A.; Shalin, A. S.; Mukhin, I. S.; Kovrov, A. E.; Krasilin, A. A.; Vinogradov, A. V.; Belov, P. A.; Simovski, C. R.
2016-08-01
Basic aspects of current solar photovoltaics (PVs) are reviewed, starting from the recently developed already-on-the-market first-generation solar cells and ending with promising but not yet commercialized third-generation cells and materials possibly leading to new cell designs. The emphasis is on the physical principles of operation of various solar cells, which are divided into several groups according to our classification scheme. To make the picture complete, some technological and economic aspects of the field are discussed. A separate chapter considers antireflection coatings and light-trapping textures — structures which, while not having appeared yet in the PV review literature, are an integral part of the solar cells.
Stone, Emma Louise; Wakefield, Andrew; Harris, Stephen; Jones, Gareth
2015-01-01
Artificial light at night is a major feature of anthropogenic global change and is increasingly recognized as affecting biodiversity, often negatively. On a global scale, newer technology white lights are replacing orange sodium lights to reduce energy waste. In 2009, Cornwall County Council (UK) commenced replacement of existing low-pressure sodium (LPS) high intensity discharge (HID) street lights with new Phillips CosmoPolis white ceramic metal halide street lights to reduce energy wastage. This changeover provided a unique collaborative opportunity to implement a before-after-control-impact field experiment to investigate the ecological effects of newly installed broad spectrum light technologies. Activity of the bat species Pipistrellus pipistrellus, P. pygmaeus and Nyctalus/Eptesicus spp. was significantly higher at metal halide than LPS lights, as found in other studies of bat activity at old technology (i.e. mercury vapour) white light types. No significant difference was found in feeding attempts per bat pass between light types, though more passes overall were recorded at metal halide lights. Species-specific attraction of bats to the metal halide lights could have cascading effects at lower trophic levels. We highlight the need for further research on possible ecosystem-level effects of light technologies before they are installed on a wide scale. PMID:25780239
The research of knitting needle status monitoring setup
NASA Astrophysics Data System (ADS)
Liu, Lu; Liao, Xiao-qing; Zhu, Yong-kang; Yang, Wei; Zhang, Pei; Zhao, Yong-kai; Huang, Hui-jie
2013-09-01
In textile production, quality control and testing is the key to ensure the process and improve the efficiency. Defect of the knitting needles is the main factor affecting the quality of the appearance of textiles. Defect detection method based on machine vision and image processing technology is universal. This approach does not effectively identify the defect generated by damaged knitting needles and raise the alarm. We developed a knitting needle status monitoring setup using optical imaging, photoelectric detection and weak signal processing technology to achieve real-time monitoring of weaving needles' position. Depending on the shape of the knitting needle, we designed a kind of Glass Optical Fiber (GOF) light guides with a rectangular port used for transmission of the signal light. To be able to capture the signal of knitting needles accurately, we adopt a optical 4F system which has better imaging quality and simple structure and there is a rectangle image on the focal plane after the system. When a knitting needle passes through position of the rectangle image, the reflected light from needle surface will back to the GOF light guides along the same optical system. According to the intensity of signals, the computer control unit distinguish that the knitting needle is broken or curving. The experimental results show that this system can accurately detect the broken needles and the curving needles on the knitting machine in operating condition.
Energy scavenging sources for biomedical sensors.
Romero, E; Warrington, R O; Neuman, M R
2009-09-01
Energy scavenging has increasingly become an interesting option for powering electronic devices because of the almost infinite lifetime and the non-dependence on fuels for energy generation. Moreover, the rise of wireless technologies promises new applications in medical monitoring systems, but these still face limitations due to battery lifetime and size. A trade-off of these two factors has typically governed the size, useful life and capabilities of an autonomous system. Energy generation from sources such as motion, light and temperature gradients has been established as commercially viable alternatives to batteries for human-powered flashlights, solar calculators, radio receivers and thermal-powered wristwatches, among others. Research on energy harvesting from human activities has also addressed the feasibility of powering wearable or implantable systems. Biomedical sensors can take advantage of human-based activities as the energy source for energy scavengers. This review describes the state of the art of energy scavenging technologies for powering sensors and instrumentation of physiological variables. After a short description of the human power and the energy generation limits, the different transduction mechanisms, recent developments and challenges faced are reviewed and discussed.
Permanent transparent color-warming glazes for dimmable and non-dimmable LED bulbs
NASA Astrophysics Data System (ADS)
Spanard, Jan-Marie A.
2014-02-01
Illuminant metameric failure is frequently experienced when viewing material samples under LED generated light vs. traditional incandescent light. LED light temperatures can be improved with phosphor coatings, but long-wave red light is still generally absent in LED "warm-white" light, resulting in metameric failure of orange-to-red objects. Drawing on techniques developed for the architectural restoration of stained glass, we find that transparent, heat-resistant, permanent, pigmented coatings can be applied to any glass, aluminum or plastic surface of an LED bulb, including the phosphor plate, dome or envelope, to produce warmer visible light than in current warm-light LED bulbs. These glazes can be applied in combination with existing technologies to better tune the LED emitted light or they may be used alone. These pigmented coatings include, but are not limited to, those made by suspending inorganic materials in potassium silicates or durable transparent pigmented resins. The pigmented resin glazes may be produced in either a clear gloss vehicle or an iridescent, light diffusing transparent base. Further, a graduated density of the tinted glazes on dimmable bulbs allow the light to change color as wattage is diminished. The glazes may be applied in the manufacturing of the bulb or marketed to current bulb owners as an after-market product to better tune the thousands of LED light bulbs currently in use.
NASA Astrophysics Data System (ADS)
Monavarian, Morteza
Despite enormous efforts and investments, the efficiency of InGaN-based green and yellow-green light emitters remains relatively low, and that limits progress in developing full color display, laser diodes, and bright light sources for general lighting. The low efficiency of light emitting devices in the green-to-yellow spectral range, also known as the "Green Gap", is considered a global concern in the LED industry. The polar c-plane orientation of GaN, which is the mainstay in the LED industry, suffers from polarization-induced separation of electrons and hole wavefunctions (also known as the "quantum confined Stark effect") and low indium incorporation efficiency that are the two main factors that contribute to the Green Gap phenomenon. One possible approach that holds promise for a new generation of green and yellow light emitting devices with higher efficiency is the deployment of nonpolar and semi-polar crystallographic orientations of GaN to eliminate or mitigate polarization fields. In theory, the use of other GaN planes for light emitters could also enhance the efficiency of indium incorporation compared to c-plane. In this thesis, I present a systematic exploration of the suitable GaN orientation for future lighting technologies. First, in order to lay the groundwork for further studies, it is important to discuss the analysis of processes limiting LED efficiency and some novel designs of active regions to overcome these limitations. Afterwards, the choice of nonpolar orientations as an alternative is discussed. For nonpolar orientation, the (1100)-oriented (mo-plane) structures on patterned Si (112) and freestanding m-GaN are studied. The semi-polar orientations having substantially reduced polarization field are found to be more promising for light-emitting diodes (LEDs) owing to high indium incorporation efficiency predicted by theoretical studies. Thus, the semi-polar orientations are given close attention as alternatives for future LED technology. (Abstract shortened by ProQuest.).
NASA Astrophysics Data System (ADS)
Shaaban, Rana; Faruque, Saleh
2018-01-01
Light emitting diodes - LEDs are modernizing the indoor illumination and replacing current incandescent and fluorescent lamps rapidly. LEDs have multiple advantages such as extremely high energy efficient, longer lifespan, and lower heat generation. Due to the ability to switch to different light intensity at a very fast rate, LED has given rise to a unique communication technology (visible light communication - VLC) used for high speed data transmission. By studying various kinds of commonly used VLC channel analysis: diffuse and line of sight channels, we presented a simply improved indoor and intra-vehicle visible light communication transmission model. Employing optical wireless communications within the vehicle, not only enhance user mobility, but also alleviate radio frequency interference, and increase efficiency by lowering the complexity of copper cabling. Moreover, a solution to eliminate ambient noise caused by environmental conditions is examined by using optical differential receiver. The simulation results show the improved received power distribution and signal to noise ratio - SNR.
Gamma-ray vortices from nonlinear inverse Thomson scattering of circularly polarized light.
Taira, Yoshitaka; Hayakawa, Takehito; Katoh, Masahiro
2017-07-10
Inverse Thomson scattering is a well-known radiation process that produces high-energy photons both in nature and in the laboratory. Nonlinear inverse Thomson scattering occurring inside an intense light field is a process which generates higher harmonic photons. In this paper, we theoretically show that the higher harmonic gamma-ray produced by nonlinear inverse Thomson scattering of circularly polarized light is a gamma-ray vortex, which means that it possesses a helical wave front and carries orbital angular momentum. Our work explains a recent experimental result regarding nonlinear inverse Thomson scattering that clearly shows an annular intensity distribution as a remarkable feature of a vortex beam. Our work implies that gamma-ray vortices should be produced in various situations in astrophysics in which high-energy electrons and intense circularly polarized light fields coexist. Nonlinear inverse Thomson scattering is a promising radiation process for realizing a gamma-ray vortex source based on currently available laser and accelerator technologies, which would be an indispensable tool for exploring gamma-ray vortex science.
Light Manipulation in Organic Photovoltaics
Ou, Qing‐Dong
2016-01-01
Organic photovoltaics (OPVs) hold great promise for next‐generation photovoltaics in renewable energy because of the potential to realize low‐cost mass production via large‐area roll‐to‐roll printing technologies on flexible substrates. To achieve high‐efficiency OPVs, one key issue is to overcome the insufficient photon absorption in organic photoactive layers, since their low carrier mobility limits the film thickness for minimized charge recombination loss. To solve the inherent trade‐off between photon absorption and charge transport in OPVs, the optical manipulation of light with novel micro/nano‐structures has become an increasingly popular strategy to boost the light harvesting efficiency. In this Review, we make an attempt to capture the recent advances in this area. A survey of light trapping schemes implemented to various functional components and interfaces in OPVs is given and discussed from the viewpoint of plasmonic and photonic resonances, addressing the external antireflection coatings, substrate geometry‐induced trapping, the role of electrode design in optical enhancement, as well as optically modifying charge extraction and photoactive layers. PMID:27840805
Synthetic Graphene Oxide Leaf for Solar Desalination with Zero Liquid Discharge.
Finnerty, Casey; Zhang, Lei; Sedlak, David L; Nelson, Kara L; Mi, Baoxia
2017-10-17
Water vapor generation through sunlight harvesting and heat localization by carbon-based porous thin film materials holds great promise for sustainable, energy-efficient desalination and water treatment. However, the applicability of such materials in a high-salinity environment emphasizing zero-liquid-discharge brine disposal has not been studied. This paper reports the characterization and evaporation performance of a nature-inspired synthetic leaf made of graphene oxide (GO) thin film material, which exhibited broadband light absorption and excellent stability in high-salinity water. Under 0.82-sun illumination (825 W/m 2 ), a GO leaf floating on water generated steam at a rate of 1.1 L per m 2 per hour (LMH) with a light-to-vapor energy conversion efficiency of 54%, while a GO leaf lifted above water in a tree-like configuration generated steam at a rate of 2.0 LMH with an energy efficiency of 78%. The evaporation rate increased with increasing light intensity and decreased with increasing salinity. During a long-term evaporation experiment with a 15 wt % NaCl solution, the GO leaf demonstrated stable performance despite gradual and eventually severe accumulation of salt crystals on the leaf surface. Furthermore, the GO leaf can be easily restored to its pristine condition by simply scraping off salt crystals from its surface and rinsing with water. Therefore, the robust high performance and relatively low fabrication cost of the synthetic GO leaf could potentially unlock a new generation of desalination technology that can be entirely solar-powered and achieve zero liquid discharge.
NASA Astrophysics Data System (ADS)
Kristensen, Anders; Yang, Joel K. W.; Bozhevolnyi, Sergey I.; Link, Stephan; Nordlander, Peter; Halas, Naomi J.; Mortensen, N. Asger
2017-01-01
Plasmonic colours are structural colours that emerge from resonant interactions between light and metallic nanostructures. The engineering of plasmonic colours is a promising, rapidly emerging research field that could have a large technological impact. We highlight basic properties of plasmonic colours and recent nanofabrication developments, comparing technology-performance indicators for traditional and nanophotonic colour technologies. The structures of interest include diffraction gratings, nanoaperture arrays, thin films, and multilayers and structures that support Mie resonances and whispering-gallery modes. We discuss plasmonic colour nanotechnology based on localized surface plasmon resonances, such as gap plasmons and hybridized disk-hole plasmons, which allow for colour printing with sub-diffraction resolution. We also address a range of fabrication approaches that enable large-area printing and nanoscale lithography compatible with complementary metal-oxide semiconductor technologies, including nanoimprint lithography and self-assembly. Finally, we review recent developments in dynamically reconfigurable plasmonic colours and in the laser-induced post-processing of plasmonic colour surfaces.
Advancing Plug-In Hybrid Technology and Flex Fuel Application on a Chrysler Minivan
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bazzi, Abdullah; Barnhart, Steven
2014-12-31
FCA US LLC viewed this DOE funding as a historic opportunity to begin the process of achieving required economies of scale on technologies for electric vehicles. The funding supported FCA US LLC’s light-duty electric drive vehicle and charging infrastructure-testing activities and enabled FCA US LLC to utilize the funding on advancing Plug-in Hybrid Electric Vehicle (PHEV) technologies to future programs. FCA US LLC intended to develop the next generations of electric drive and energy batteries through a properly paced convergence of standards, technology, components, and common modules, as well as first-responder training and battery recycling. To support the development ofmore » a strong, commercially viable supplier base, FCA US LLC also used this opportunity to evaluate various designated component and sub-system suppliers. The original project proposal was submitted in December 2009 and selected in January 2010. The project ended in December 2014.« less
ICT Learning by Older Adults and Their Attitudes toward Computer Use
González, Antonio; Ramírez, María Paz; Viadel, Vicente
2015-01-01
Information and communication technologies have proven to be an effective way of helping older adults improve independence outcomes, but such technologies are yet not widely used by this segment of the population. This paper aims to study computer use and senior citizens' attitudes toward computer technology in the context of a 20-hour course in basic skills. A questionnaire was used to conduct pre- and postcourse analyses with a sample of 191 adults over the age of 60. The findings show that direct contact with computers generates more positive attitudes toward computer use and also positive relationships with attitudes, user behavior, training expectations, and self-confidence. Results are discussed in the light of need-to-know attitudes toward computer use and training in new technologies as an opportunity for life-long learning and for improving quality of life in old age. PMID:26346158
NASA Technical Reports Server (NTRS)
Postman, Marc; Brown, Tom; Sembach, Kenneth; Giavalisco, Mauro; Traub, Wesley; Stapelfeldt, Karl; Calzetti, Daniela; Oegerle, William; Rich, R. Michael; Stahl, H. Philip;
2011-01-01
The Advanced Technology Large-Aperture Space Telescope (ATLAST) is a concept for an 8-meter to 16-meter UVOIR space observatory for launch in the 2025-2030 era. ATLAST will allow astronomers to answer fundamental questions at the forefront of modern astrophysics, including "Is there life elsewhere in the Galaxy?" We present a range of science drivers that define the main performance requirements for ATLAST (8 to 16 milliarcsec angular resolution, diffraction limited imaging at 0.5 m wavelength, minimum collecting area of 45 square meters, high sensitivity to light wavelengths from 0.1 m to 2.4 m, high stability in wavefront sensing and control). We will also discuss the synergy between ATLAST and other anticipated future facilities (e.g., TMT, EELT, ALMA) and the priorities for technology development that will enable the construction for a cost that is comparable to current generation observatory-class space missions.
El-Sharkawy, Yasser H; Elbasuney, Sherif
2017-08-01
Laser photoacoustic spectroscopy (LPAS) is an attractive technology in terms of simplicity, ruggedness, and overall sensitivity; it detects the time dependent heat generated (thermo-elastic effect) in the target via interaction with pulsed optical radiation. This study reports on novel LPAS technique that offers instant and standoff detection capabilities of trace explosives. Over the current study, light is generated using pulsed Q-switched Nd:YAG laser; the generated photoacoustic response in stimulated explosive material offers signature values that depend on the optical, thermal, and acoustical properties. The generated acoustic waves were captured using piezoelectric transducer as well as novel customized optical sensor with remotely laser interferometer probe. A digital signal processing algorithm was employed to identify explosive material signatures via calculation of characteristic optical properties (absorption coefficient), sound velocity, and frequency response of the generated photoacoustic signal. Customized LPAS technique was employed for instantaneous trace detection of three main different high explosive materials including TNT, RDX, and HMX. The main outcome of this study is that the novel customized optical sensor signals were validated with traditional piezoelectric transducer. Furthermore, the customized optical sensor offered standoff detection capabilities (10cm), fast response, high sensitivity, and enhanced signal to noise ratio. This manuscript shaded the light on the instant detection of trace explosive materials from significant standoffs using novel customized LPAS technique. Copyright © 2017 Elsevier B.V. All rights reserved.
DPSSL for direct dicing and drilling of dielectrics
NASA Astrophysics Data System (ADS)
Ashkenasi, David; Schwagmeier, M.
2007-02-01
New strategies in laser micro processing of glasses and other optically transparent materials are being developed with increasing interest and intensity using diode pumped solid state laser (DPSSL) systems generating short or ultra-short pulses in the optical spectra at good beam quality. Utilizing non-linear absorption channels, it can be demonstrated that ns green (532 nm) laser light can scribe, dice, full body cut and drill (flat) borofloat and borosilicate glasses at good quality. Outside of the correct choice in laser parameters, an intelligent laser beam management plays an important role in successful micro processing of glass. This application characterizes a very interesting alternative where standard methods demonstrate severe limitations such as diamond dicing, CO2 laser treatment or water jet cutting, especially for certain type of optical materials and/or geometric conditions. Application near processing examples using different DPSSL systems generating ns pulsed light at 532 nm in TEM 00 at average powers up to 10 W are presented and discussed in respect to potential applications in display technology, micro electronics and optics.
Parameters affecting the photocatalytic degradation of dyes using TiO2: a review
NASA Astrophysics Data System (ADS)
Reza, Khan Mamun; Kurny, ASW; Gulshan, Fahmida
2017-07-01
Traditional chemical, physical and biological processes for treating wastewater containing textile dye have such disadvantages as high cost, high energy requirement and generation of secondary pollution during treatment process. The advanced oxidation processes technology has been attracting growing attention for the decomposition of organic dyes. Such processes are based on the light-enhanced generation of highly reactive hydroxyl radicals, which oxidize the organic matter in solution and convert it completely into water, CO2 and inorganic compounds. In this presentation, the photocatalytic degradation of dyes in aqueous solution using TiO2 as photocatalyst under solar and UV irradiation has been reviewed. It is observed that the degradation of dyes depends on several parameters such as pH, catalyst concentration, substrate concentration and the presence of oxidants. Reaction temperature and the intensity of light also affect the degradation of dyes. Particle size, BET-surface area and different mineral forms of TiO2 also have influence on the degradation rate.
Status and Aims of the DUMAND Neutrino Project: the Ocean as a Neutrino Detector
DOE R&D Accomplishments Database
Roberts, A.; Blood, H.; Learned, J.; Reines, F.
1976-07-01
The possibility of using the ocean as a neutrino detector is considered. Neutrino-produced interactions result in charged particles that generate Cherenkov radiation in the water, which can be detected by light-gathering equipment and photomultipliers. The properties of the ocean as seen from this standpoint are critically examined, and the advantages and disadvantages pointed out. Possible uses for such a neutrino detector include (1) the detection of neutrinos emitted in gravitational collapse of stars (supernova production), not only in our own galaxy, but in other galaxies up to perhaps twenty-million light-years away, (2) the extension of high-energy neutrino physics, as currently practiced up to 200 GeV at high-energy accelerators, to energies up to 50 times higher, using neutrinos generated in the atmosphere by cosmic rays, and (3) the possible detection of neutrinos produced by cosmic-ray interactions outside the earth`s atmosphere. The technology for such an undertaking seems to be within reach.
NASA Astrophysics Data System (ADS)
Qu, Yuanyuan; Li, Feng; Zhou, Hongcai; Zhao, Mingwen
2016-01-01
Light isotopes separation, such as 3He/4He, H2/D2, H2/T2, etc., is crucial for various advanced technologies including isotope labeling, nuclear weapons, cryogenics and power generation. However, their nearly identical chemical properties made the separation challenging. The low productivity of the present isotopes separation approaches hinders the relevant applications. An efficient membrane with high performance for isotopes separation is quite appealing. Based on first-principles calculations, we theoretically demonstrated that highly efficient light isotopes separation, such as 3He/4He, can be reached in a porous graphene-like carbon nitride material via quantum sieving effect. Under moderate tensile strain, the quantum sieving of the carbon nitride membrane can be effectively tuned in a continuous way, leading to a temperature window with high 3He/4He selectivity and permeance acceptable for efficient isotopes harvest in industrial application. This mechanism also holds for separation of other light isotopes, such as H2/D2, H2/T2. Such tunable quantum sieving opens a promising avenue for light isotopes separation for industrial application.
Visible emission from bismuth-doped yttrium oxide thin films for lighting and display applications.
Scarangella, Adriana; Fabbri, Filippo; Reitano, Riccardo; Rossi, Francesca; Priolo, Francesco; Miritello, Maria
2017-12-11
Due to the great development of light sources for several applications from displays to lighting, great efforts are devoted to find stable and efficient visible emitting materials. Moreover, the requirement of Si compatibility could enlarge the range of applications inside microelectronic chips. In this scenario, we have studied the emission properties of bismuth doped yttrium oxide thin films grown on crystalline silicon. Under optical pumping at room temperature a stable and strong visible luminescence has been observed. In particular, by the involvement of Bi ions in the two available lattice sites, the emission can be tuned from violet to green by changing the excitation wavelength. Moreover, under electron beam at low accelerating voltages (3 keV) a blue emission with high efficiency and excellent stability has been recorded. The color is generated by the involvement of Bi ions in both the lattice sites. These peculiarities make this material interesting as a luminescent medium for applications in light emitting devices and field emission displays by opening new perspectives for the realization of silicon-technology compatible light sources operating at room temperature.
Casali, N.; Vignati, Marco; Beeman, J. W.; ...
2015-01-14
CUORE, an array of 988 TeOmore » $$_2$$ bolometers, is about to be one of the most sensitive experiments searching for neutrinoless double-beta decay. Its sensitivity could be further improved by removing the background from α radioactivity. A few years ago it was pointed out that the signal from βs can be tagged by detecting the emitted Cherenkov light, which is not produced by αs. In this paper we confirm this possibility. For the first time we measured the Cherenkov light emitted by a CUORE crystal, and found it to be 100 eV at the Q-value of the decay. To completely reject the α background, we compute that one needs light detectors with baseline noise below 20 eV RMS, a value which is 3–4 times smaller than the average noise of the bolometric light detectors we are using. We point out that an improved light detector technology must be developed to obtain TeO$$_2$$ bolometric experiments able to probe the inverted hierarchy of neutrino masses.« less
Micro-combs: A novel generation of optical sources
NASA Astrophysics Data System (ADS)
Pasquazi, Alessia; Peccianti, Marco; Razzari, Luca; Moss, David J.; Coen, Stéphane; Erkintalo, Miro; Chembo, Yanne K.; Hansson, Tobias; Wabnitz, Stefan; Del'Haye, Pascal; Xue, Xiaoxiao; Weiner, Andrew M.; Morandotti, Roberto
2018-01-01
The quest towards the integration of ultra-fast, high-precision optical clocks is reflected in the large number of high-impact papers on the topic published in the last few years. This interest has been catalysed by the impact that high-precision optical frequency combs (OFCs) have had on metrology and spectroscopy in the last decade [1-5]. OFCs are often referred to as optical rulers: their spectra consist of a precise sequence of discrete and equally-spaced spectral lines that represent precise marks in frequency. Their importance was recognised worldwide with the 2005 Nobel Prize being awarded to T.W. Hänsch and J. Hall for their breakthrough in OFC science [5]. They demonstrated that a coherent OFC source with a large spectrum - covering at least one octave - can be stabilised with a self-referenced approach, where the frequency and the phase do not vary and are completely determined by the source physical parameters. These fully stabilised OFCs solved the challenge of directly measuring optical frequencies and are now exploited as the most accurate time references available, ready to replace the current standard for time. Very recent advancements in the fabrication technology of optical micro-cavities [6] are contributing to the development of OFC sources. These efforts may open up the way to realise ultra-fast and stable optical clocks and pulsed sources with extremely high repetition-rates, in the form of compact and integrated devices. Indeed, the fabrication of high-quality factor (high-Q) micro-resonators, capable of dramatically amplifying the optical field, can be considered a photonics breakthrough that has boosted not only the scientific investigation of OFC sources [7-13] but also of optical sensors and compact light modulators [6,14]. In this framework, the demonstration of planar high-Q resonators, compatible with silicon technology [10-14], has opened up a unique opportunity for these devices to provide entirely new capabilities for photonic-integrated technologies. Indeed, it is well acknowledged by the electronics industry that future generations of computer processing chips will inevitably require an extremely high density of copper-based interconnections, significantly increasing the chip power dissipation to beyond practical levels [15-17]; hence, conventional approaches to chip design must undergo radical changes. On-chip optical networks, or optical interconnects, can offer high speed and low energy per-transferred-bit, and micro-resonators are widely seen as a key component to interface the electronic world with photonics. Many information technology industries have recently focused on the development of integrated ring resonators to be employed for electrically-controlled light modulators [14-17], greatly advancing the maturity of micro-resonator technology as a whole. Recently [11-13], the demonstration of OFC sources in micro-resonators fabricated in electronic (i.e. in complementary metal oxide semiconductor (CMOS)) compatible platforms has given micro-cavities an additional appeal, with the possibility of exploiting them as light sources in microchips. This scenario is creating fierce competition in developing highly efficient OFC generators based on micro-cavities which can radically change the nature of information transport and processing. Even in telecommunications, perhaps a more conventional environment for optical technologies, novel time-division multiplexed optical systems will require extremely stable optical clocks at ultra-high pulse repetition-rates towards the THz scale. Furthermore, arbitrary pulse generators based on OFC [18,19] are seen as one of the most promising solutions for this next generation of high-capacity optical coherent communication systems. This review will summarise the recent exciting achievements in the field of micro-combs, namely optical frequency combs based on high-Q micro-resonators, with a perspective on both the potential of this technology, as well as the open questions and challenges that remain.
Active Matrix Organic Light Emitting Diode (AMOLED) Environmental Test Report
NASA Technical Reports Server (NTRS)
Salazar, George A.
2013-01-01
This report focuses on the limited environmental testing of the AMOLED display performed as an engineering evaluation by The NASA Johnson Space Center (JSC)-specifically. EMI. Thermal Vac, and radiation tests. The AMOLED display is an active-matrix Organic Light Emitting Diode (OLED) technology. The testing provided an initial understanding of the technology and its suitability for space applications. Relative to light emitting diode (LED) displays or liquid crystal displays (LCDs), AMOLED displays provide a superior viewing experience even though they are much lighter and smaller, produce higher contrast ratio and richer colors, and require less power to operate than LCDs. However, AMOLED technology has not been demonstrated in a space environment. Therefore, some risks with the technology must be addressed before they can be seriously considered for human spaceflight. The environmental tests provided preliminary performance data on the ability of the display technology to handle some of the simulated induced space/spacecraft environments that an AMOLED display will see during a spacecraft certification test program. This engineering evaluation is part of a Space Act Agreement (SM) between The NASA/JSC and Honeywell International (HI) as a collaborative effort to evaluate the potential use of AMOLED technology for future human spaceflight missions- both government-led and commercial. Under this SM, HI is responsible for doing optical performance evaluation, as well as temperature and touch screen studies. The NASA/JSC is responsible for performing environmental testing comprised of EMI, Thermal Vac, and radiation tests. Additionally, as part of the testing, limited optical data was acquired to assess performance as the display was subjected to the induced environments. The NASA will benefit from this engineering evaluation by understanding AMOLED suitability for future use in space as well as becoming a smarter buyer (or developer) of the technology. HI benefits from the environmental testing results by understanding its performance limitations/shortcomings to improve subsequent generations of AMOLED technology. Note that the AMOLED used in this test was not deSigned for the space environment but rather for commercial/industrial terrestrial applications.
Two-mode squeezed light source for quantum illumination and quantum imaging
NASA Astrophysics Data System (ADS)
Masada, Genta
2015-09-01
We started to research quantum illumination radar and quantum imaging by utilizing high quality continuous-wave two-mode squeezed light source as a quantum entanglement resource. Two-mode squeezed light is a macroscopic quantum entangled state of the electro-magnetic field and shows strong correlation between quadrature phase amplitudes of each optical field. One of the most effective methods to generate two-mode squeezed light is combining two independent single-mode squeezed lights by using a beam splitter with relative phase of 90 degrees between each optical field. As a first stage of our work we are developing two-mode squeezed light source for exploring the possibility of quantum illumination radar and quantum imaging. In this article we introduce current development of experimental investigation of single-mode squeezed light. We utilize a sub-threshold optical parametric oscillator with bow-tie configuration which includes a periodically-polled potassium titanyl phosphate crystal as a nonlinear optical medium. We observed the noise level of squeezed quadrature -3.08+/-0.13 dB and anti-squeezed quadrature at 9.29+/-0.13 dB, respectively. We also demonstrated the remote tuning of squeezing level of the light source which leads to the technology for tuning the quantum entanglement in order to adapt to the actual environmental condition.
NASA Astrophysics Data System (ADS)
Ryu, Donghyeon; Castaño, Nicolas; Bhakta, Raj; Kimberley, Jamie
2017-08-01
The objective of this study is to understand light emission characteristics of fracto-mechanoluminescent (FML) europium tetrakis(dibenzoylmethide)-triethylammonium (EuD4TEA) crystals under high strain-rate compressive loading. As a sensing material that can play a pivotal role for the self-powered impact sensor technology, it is important to understand transformative light emission characteristics of the FML EuD4TEA crystals under high strain-rate compressive loading. First, EuD4TEA crystals were synthesized and embedded into polydimethylsiloxane (PDMS) elastomer to fabricate EuD4TEA-PDMS composite test specimens. Second, the prepared EuD4TEA-PDMS composites were tested using the modified Kolsky bar setup equipped with a high-speed camera. Third, FML light emission was captured to yield 12 bit grayscale video footage, which was processed to quantify the FML light emission. Finally, quantitative parameters were generated by taking into account pixel values and population of pixels of the 12 bit grayscale images to represent FML light intensity. The FML light intensity was correlated with high strain-rate compressive strain and strain rate to understand the FML light emission characteristics under high strain-rate compressive loading that can result from impact occurrences.
Colour gamut enhancement with remote light conversion mechanism
NASA Astrophysics Data System (ADS)
Koseoglu, D.; Sezer, Y. S.; Karsli, K.
2018-01-01
The backlight unit spectrum of liquid crystal displays (LCD) directly affects the colour gamut. With the invention of GaN based blue light emitting diodes (LED), phosphors and quantum dots (QD) have gained considerable scientific interest due to their broad range of applications especially in lighting and display technologies. These phosphors and QDs are used to convert the blue light of the LEDs into white in general lighting. On the other hand, in display systems, they are used to generate red and green bands. There are different application methods such as on-chip and remote configurations. In this study, we concentrate on remote phosphor and QD backlight configurations where the light conversion is done away from the chips. In our display designs, we used GaN based blue LED lateral chips as an excitation source, on the other hand, light conversion layers were placed in backlight units as a thin film for the emission of green and red bands. The mixing ratios of these composite layers were arranged to match the emission spectrum of the blue LEDs and the light conversion layer to the colour filters of the LCD, so that the green, blue, and red bands efficiently widens the colour space. The results were also compared with the on-chip phosphor arrangements.
Organic electronics on fibers for energy conversion applications
NASA Astrophysics Data System (ADS)
O'Connor, Brendan T.
Currently, there is great demand for pollution-free and renewable sources of electricity. Solar cells are particularly attractive from the standpoint of sunlight abundance. However, truly widespread adoption of solar cells is impeded by the high cost and poor scalability of existing technologies. For example, while 53,000 mi2 of 10% efficient solar cell modules would be required to supply the current U.S. energy demand, only about 50 mi2 have been installed worldwide. Organic semiconductors potentially offer a route to realizing low-cost solar cell modules, but currently suffer from low conversion efficiency. For organic-based solar cells to become commercially viable, further research is required to improve device performance, develop scalable manufacturing methods, and reduce installation costs via, for example, novel device form factors. This thesis makes several contributions to the field of organic solar cells, including the replacement of costly and brittle indium tin oxide (ITO) electrodes by inexpensive and malleable, thin metal films, and the application of external dielectric coatings to improve power conversion efficiency. Furthermore, we show that devices with non-planar geometries (e.g. organic solar cells deposited onto long fibers) can have higher efficiencies than conventional planar devices. Building on these results, we demonstrate novel fiber-based organic light emitting devices (OLEDs) that offer substantially improved color quality and manufacturability as a next-generation solid-state lighting technology. An intriguing possibility afforded by the fiber-based device architectures is the ability to integrate energy conversion and lighting functionalities with textiles, a mature, commodity-scale technology.
Guzzinati, Giulio; Béché, Armand; Lourenço-Martins, Hugo; Martin, Jérôme; Kociak, Mathieu; Verbeeck, Jo
2017-04-12
Plasmonics, the science and technology of the interaction of light with metallic objects, is fundamentally changing the way we can detect, generate and manipulate light. Although the field is progressing swiftly, thanks to the availability of nanoscale manufacturing and analysis methods, fundamental properties such as the plasmonic excitations' symmetries cannot be accessed directly, leading to a partial, sometimes incorrect, understanding of their properties. Here we overcome this limitation by deliberately shaping the wave function of an electron beam to match a plasmonic excitations' symmetry in a modified transmission electron microscope. We show experimentally and theoretically that this offers selective detection of specific plasmon modes within metallic nanoparticles, while excluding modes with other symmetries. This method resembles the widespread use of polarized light for the selective excitation of plasmon modes with the advantage of locally probing the response of individual plasmonic objects and a far wider range of symmetry selection criteria.
Noncritical generation of nonclassical frequency combs via spontaneous rotational symmetry breaking
NASA Astrophysics Data System (ADS)
Navarrete-Benlloch, Carlos; Patera, Giuseppe; de Valcárcel, Germán J.
2017-10-01
Synchronously pumped optical parametric oscillators (SPOPOs) are optical cavities driven by mode-locked lasers, and containing a nonlinear crystal capable of down-converting a frequency comb to lower frequencies. SPOPOs have received a lot of attention lately because their intrinsic multimode nature makes them compact sources of quantum correlated light with promising applications in modern quantum information technologies. In this work we show that SPOPOs are also capable of accessing the challenging and interesting regime where spontaneous symmetry breaking confers strong nonclassical properties to the emitted light, which has eluded experimental observation so far. Apart from opening the possibility of studying experimentally this elusive regime of dissipative phase transitions, our predictions will have a practical impact, since we show that spontaneous symmetry breaking provides a specific spatiotemporal mode with large quadrature squeezing for any value of the system parameters, turning SPOPOs into robust sources of highly nonclassical light above threshold.
Electrical characteristics of silicon nanowire CMOS inverters under illumination.
Yoo, Jeuk; Kim, Yoonjoong; Lim, Doohyeok; Kim, Sangsig
2018-02-05
In this study, we examine the electrical characteristics of complementary metal-oxide-semiconductor (CMOS) inverters with silicon nanowire (SiNW) channels on transparent substrates under illumination. The electrical characteristics vary with the wavelength and power of light due to the variation in the generation rates of the electric-hole pairs. Compared to conventional optoelectronic devices that sense the on/off states by the variation in the current, our device achieves the sensing of the on/off states with more precision by using the voltage variation induced by the wavelength or intensity of light. The device was fabricated on transparent substrates to maximize the light absorption using conventional CMOS technologies. The key difference between our SiNW CMOS inverters and conventional optoelectronic devices is the ability to control the flow of charge carriers more effectively. The improved sensitivity accomplished with the use of SiNW CMOS inverters allows better control of the on/off states.
Modular design of the LED vehicle projector headlamp system.
Hsieh, Chi-Chang; Li, Yan-Huei; Hung, Chih-Ching
2013-07-20
A well designed headlamp for a vehicle lighting system is very important as it provides drivers with safe and comfortable driving conditions at night or in dark places. With the advances of the semiconductor technology, the LED has become the fourth generation lighting source in the auto industry. In this study, we will propose a LED vehicle projector headlamp system. This headlamp system contains several LED headlamp modules, and every module of it includes four components: focused LEDs, asymmetric metal-based plates, freeform surfaces, and condenser lenses. By optimizing the number of LED headlamp modules, the proposed LED vehicle projector headlamp system has only five LED headlamp modules. It not only provides the low-beam cutoff without a shield, but also meets the requirements of the ECE R112 regulation. Finally, a prototype of the LED vehicle projector headlamp system was assembled and fabricated to create the correct light pattern.
Phase Sensitive Demodulation in Multiphoton Microscopy
NASA Astrophysics Data System (ADS)
Fisher, Walt G.; Piston, David W.; Wachter, Eric A.
2002-06-01
Multiphoton laser scanning microscopy offers advantages in depth of penetration into intact samples over other optical sectioning techniques. To achieve these advantages it is necessary to detect the emitted light without spatial filtering. In this nondescanned (nonconfocal) approach, ambient room light can easily contaminate the signal, forcing experiments to be performed in absolute darkness. For multiphoton microscope systems employing mode-locked lasers, signal processing can be used to reduce such problems by taking advantage of the pulsed characteristics of such lasers. Specifically, by recovering fluorescence generated at the mode-locked frequency, interference from stray light and other ambient noise sources can be significantly reduced. This technology can be adapted to existing microscopes by inserting demodulation circuitry between the detector and data collection system. The improvement in signal-to-noise ratio afforded by this approach yields a more robust microscope system and opens the possibility of moving multiphoton microscopy from the research lab to more demanding settings, such as the clinic.
CALDER: Cryogenic light detectors for background-free searches
NASA Astrophysics Data System (ADS)
Di Domizio, S.; Bellini, F.; Cardani, L.; Casali, N.; Castellano, M. G.; Colantoni, I.; Cosmelli, C.; Cruciani, A.; D'Addabbo, A.; Martinez, M.; Minutolo, L.; Tomei, C.; Vignati, M.
2018-01-01
CALDER is a R&D project for the development of cryogenic light detectors with an active surface of 5x5cm2 and an energy resolution of 20 eV RMS for visible and UV photons. These devices can enhance the sensitivity of next generation large mass bolometric detectors for rare event searches, providing an active background rejection method based on particle discrimination. A CALDER detector is composed by a large area Si absorber substrate with superconducting kinetic inductance detectors (KIDs) deposited on it. The substrate converts the incoming light into athermal phonons, that are then sensed by the KIDs. KID technology combine fabrication simplicity with natural attitude to frequency-domain multiplexing, making it an ideal candidate for a large scale bolometric experiments. We will give an overview of the CALDER project and show the performances obtained with prototype detectors both in terms of energy resolution and efficiency.
NASA Astrophysics Data System (ADS)
Ilias, Samir; Picard, Francis; Larouche, Carl; Kruzelecky, Roman; Jamroz, Wes
2017-11-01
16x1 programmable microshutter arrays allowing control of the light transmitted through a transparent substrate supporting the array were successfully fabricated using surface micromachining technology. Each microshutter is basically an electrostatic zipping actuator having a curved shape induced by a stress gradient through the actuator thickness. When a sufficient voltage is applied between the microshutter and the actuation electrode surrounding the associated microslit area, the generated electrostatic force pulls the actuator down to the substrate which closes the microslit. Opening the slit relies on the restoring force. High light transmission through the slit area is obtained with the actuator in the open position and excellent light blocking is observed when the shutter is closed. Static and dynamic responses of the device were determined. The pull-in voltage to close the microslit was about 110 V and the response times to close and open the microslit were about 2 ms and 7 ms, respectively.
Stone, Emma Louise; Wakefield, Andrew; Harris, Stephen; Jones, Gareth
2015-05-05
Artificial light at night is a major feature of anthropogenic global change and is increasingly recognized as affecting biodiversity, often negatively. On a global scale, newer technology white lights are replacing orange sodium lights to reduce energy waste. In 2009, Cornwall County Council (UK) commenced replacement of existing low-pressure sodium (LPS) high intensity discharge (HID) street lights with new Phillips CosmoPolis white ceramic metal halide street lights to reduce energy wastage. This changeover provided a unique collaborative opportunity to implement a before-after-control-impact field experiment to investigate the ecological effects of newly installed broad spectrum light technologies. Activity of the bat species Pipistrellus pipistrellus, P. pygmaeus and Nyctalus/Eptesicus spp. was significantly higher at metal halide than LPS lights, as found in other studies of bat activity at old technology (i.e. mercury vapour) white light types. No significant difference was found in feeding attempts per bat pass between light types, though more passes overall were recorded at metal halide lights. Species-specific attraction of bats to the metal halide lights could have cascading effects at lower trophic levels. We highlight the need for further research on possible ecosystem-level effects of light technologies before they are installed on a wide scale. © 2015 The Author(s) Published by the Royal Society. All rights reserved.
Knowing Generation Y: a new generation of nurses in practice.
Chung, Stephanie M
Generation Y is commonly defined as those people born between 1980 and 2000, now aged in their 20s and 30s. Their grandparents experienced post-World War II reconstruction, their parents the economic boom of the 1980s. There are currently 81 million individuals in the Generation Y cohort in the USA, making it the second-largest, and possibly most influential, cohort since World War II (Manion, 2009). Members of Generation Y are diverse, technologically advanced and vocal about their opinions. They tend to resist traditional hierarchy, want recognition/reward for achievements and distrust institutions. Knowing these characteristics is useful for nurse managers, preceptors and team members working with members of Generation Y. Studies have proven that Generation Y is challenging the nursing workforce through rapid turnover (Cogin, 2012). This article explores a theoretical model that predicts retention and/or turnover of nurses in light of Generation Y behaviours and motivators-for example, moving from agency to agency rather than devoting many years to a single practice. Further research is needed to find out whether these behaviours and motivators are unique to Generation Y alone.
Emissions impacts and benefits of plug-in hybrid electric vehicles and vehicle-to-grid services
Sioshansi, Ramteen; Denholm, Paul
2009-01-22
Plug-in hybrid electric vehicles (PHEVs) have been promoted as a potential technology to reduce emissions of greenhouse gases and other pollutants by using electricity instead of petroleum, and by improving electric system efficiency by providing vehicle-to-grid (V2G) services. We use an electric power system model to explicitly evaluate the change in generator dispatches resulting from PHEV deployment in the Texas grid, and apply fixed and non-parametric estimates of generator emissions rates, to estimate the resulting changes in generation emissions. Here, we find that by using the flexibility of when vehicles may be charged, generator efficiency can be increased substantially. Bymore » changing generator dispatch, a PHEV fleet of up to 15% of light-duty vehicles can actually decrease net generator NO x emissions during the ozone season, despite the additional charging load. By adding V2G services, such as spinning reserves and energy storage, CO 2, SO 2, and NO x emissions can be reduced even further.« less
Emissions impacts and benefits of plug-in hybrid electric vehicles and vehicle-to-grid services.
Sioshansi, Ramteen; Denholm, Paul
2009-02-15
Plug-in hybrid electric vehicles (PHEVs) have been promoted as a potential technology to reduce emissions of greenhouse gases and other pollutants by using electricity instead of petroleum, and byimproving electric system efficiency by providing vehicle-to-grid (V2G) services. We use an electric power system model to explicitly evaluate the change in generator dispatches resulting from PHEV deployment in the Texas grid, and apply fixed and non-parametric estimates of generator emissions rates, to estimate the resulting changes in generation emissions. We find that by using the flexibility of when vehicles may be charged, generator efficiency can be increased substantially. By changing generator dispatch, a PHEVfleet of up to 15% of light-duty vehicles can actually decrease net generator NOx emissions during the ozone season, despite the additional charging load. By adding V2G services, such as spinning reserves and energy storage, CO2, SO2, and NOx emissions can be reduced even further.
An introduction to the Astro Edge solar array
NASA Technical Reports Server (NTRS)
Spence, B. R.; Marks, G. W.
1994-01-01
The Astro Edge solar array is a new and innovative low concentrator power generating system which has been developed for applications requiring high specific power, high stiffness, low risk, light modular construction which utilizes conventional materials and technology, and standard photovoltaic solar cells and laydown processes. Mechanisms, restraint/release devices, wiring harnesses, substrates, and support structures are designed to be simple, functional, lightweight, and modular. A brief overview of the Astro Edge solar array is discussed.
Packaging and Embedded Electronics for the Next Generation
NASA Technical Reports Server (NTRS)
Sampson, Michael J.
2010-01-01
This viewgraph presentation describes examples of electronic packaging that protects an electronic element from handling, contamination, shock, vibration and light penetration. The use of Hermetic and non-hermetic packaging is also discussed. The topics include: 1) What is Electronic Packaging? 2) Why Package Electronic Parts? 3) Evolution of Packaging; 4) General Packaging Discussion; 5) Advanced non-hermetic packages; 6) Discussion of Hermeticity; 7) The Class Y Concept and Possible Extensions; 8) Embedded Technologies; and 9) NEPP Activities.
Applications of Light Emitting Diodes in Health Care.
Dong, Jianfei; Xiong, Daxi
2017-11-01
Light emitting diodes (LEDs) have become the main light sources for general lighting, due to their high lumen efficiency and long life time. Moreover, their high bandwidth and the availability of diverse wavelength contents ranging from ultraviolet to infrared empower them with great controllability in tuning brightness, pulse durations and spectra. These parameters are the essential ingredients of the applications in medical imaging and therapies. Despite the fast advances in both LED technologies and their applications, few reviews have been seen to link the controllable emission properties of LEDs to these applications. The objective of this paper is to bridge this gap by reviewing the main control techniques of LEDs that enable creating enhanced lighting patterns for imaging and generating effective photon doses for photobiomodulation. This paper also provides the basic mechanisms behind the effective LED therapies in treating cutaneous and neurological diseases. The emerging field of optogenetics is also discussed with a focus on the application of LEDs. The multidisciplinary topics reviewed in this paper can help the researchers in LEDs, imaging, light therapy and optogenetics better understand the basic principles in each other's field; and hence to stimulate the application of LEDs in health care.
Organic Light-Emitting Transistors: Materials, Device Configurations, and Operations.
Zhang, Congcong; Chen, Penglei; Hu, Wenping
2016-03-09
Organic light-emitting transistors (OLETs) represent an emerging class of organic optoelectronic devices, wherein the electrical switching capability of organic field-effect transistors (OFETs) and the light-generation capability of organic light-emitting diodes (OLEDs) are inherently incorporated in a single device. In contrast to conventional OFETs and OLEDs, the planar device geometry and the versatile multifunctional nature of OLETs not only endow them with numerous technological opportunities in the frontier fields of highly integrated organic electronics, but also render them ideal scientific scaffolds to address the fundamental physical events of organic semiconductors and devices. This review article summarizes the recent advancements on OLETs in light of materials, device configurations, operation conditions, etc. Diverse state-of-the-art protocols, including bulk heterojunction, layered heterojunction and laterally arranged heterojunction structures, as well as asymmetric source-drain electrodes, and innovative dielectric layers, which have been developed for the construction of qualified OLETs and for shedding new and deep light on the working principles of OLETs, are highlighted by addressing representative paradigms. This review intends to provide readers with a deeper understanding of the design of future OLETs. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
None
2017-12-09
Learn what it will take to create tomorrow's net-zero energy home as scientists reveal the secrets of cool roofs, smart windows, and computer-driven energy control systems. The net-zero energy home: Scientists are working to make tomorrow's homes more than just energy efficient -- they want them to be zero energy. Iain Walker, a scientist in the Lab's Energy Performance of Buildings Group, will discuss what it takes to develop net-zero energy houses that generate as much energy as they use through highly aggressive energy efficiency and on-site renewable energy generation. Talking back to the grid: Imagine programming your house to use less energy if the electricity grid is full or price are high. Mary Ann Piette, deputy director of Berkeley Lab's building technology department and director of the Lab's Demand Response Research Center, will discuss how new technologies are enabling buildings to listen to the grid and automatically change their thermostat settings or lighting loads, among other demands, in response to fluctuating electricity prices. The networked (and energy efficient) house: In the future, your home's lights, climate control devices, computers, windows, and appliances could be controlled via a sophisticated digital network. If it's plugged in, it'll be connected. Bruce Nordman, an energy scientist in Berkeley Lab's Energy End-Use Forecasting group, will discuss how he and other scientists are working to ensure these networks help homeowners save energy.
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
Learn what it will take to create tomorrow's net-zero energy home as scientists reveal the secrets of cool roofs, smart windows, and computer-driven energy control systems. The net-zero energy home: Scientists are working to make tomorrow's homes more than just energy efficient -- they want them to be zero energy. Iain Walker, a scientist in the Lab's Energy Performance of Buildings Group, will discuss what it takes to develop net-zero energy houses that generate as much energy as they use through highly aggressive energy efficiency and on-site renewable energy generation. Talking back to the grid: Imagine programming your house tomore » use less energy if the electricity grid is full or price are high. Mary Ann Piette, deputy director of Berkeley Lab's building technology department and director of the Lab's Demand Response Research Center, will discuss how new technologies are enabling buildings to listen to the grid and automatically change their thermostat settings or lighting loads, among other demands, in response to fluctuating electricity prices. The networked (and energy efficient) house: In the future, your home's lights, climate control devices, computers, windows, and appliances could be controlled via a sophisticated digital network. If it's plugged in, it'll be connected. Bruce Nordman, an energy scientist in Berkeley Lab's Energy End-Use Forecasting group, will discuss how he and other scientists are working to ensure these networks help homeowners save energy.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liu, Geyuan
My research projects are focused on application of photonics, optics and micro- fabrication technology in energy related fields. Photonic crystal fabrication research has the potential to help us generate and use light more efficiently. In order to fabricate active 3D woodpile photonic structure devices, a woodpile template is needed to enable the crystal growth process. We developed a silica woodpile template fabrication process based on two polymer transfer molding technique. A silica woodpile template is demonstrated to work with temperature up to 900 C. It provides a more economical way to explore making better 3D active woodpile photonic devices likemore » 3D photonic light emitting diodes (LED). Optical research on solar cell testing has the potential to make our energy generation more e cient and greener. PL imaging and LBIC mapping are used to measure CdTe solar cells with different back contacts. A strong correlation between PL image defects and LBIC map defects is observed. This opens up potential application for PL imaging in fast solar cell inspection. 2D laser IV scan shows its usage in 2D parameter mapping. We show its ability to generate important information about solar cell performance locally around PL image defects.« less
Ultraviolet light-an FDA approved technology
USDA-ARS?s Scientific Manuscript database
Ultraviolet Light (254 nm) is a U.S. Food and Drug Administration approved nonthermal intervention technology that can be used for decontamination of food and food contact surfaces. Ultraviolet light is a green technology that leaves no chemical residues. Results from our laboratory indicate that ex...
Assessment of the performance of light-emitting diode roadway lighting technology.
DOT National Transportation Integrated Search
2015-10-01
This study, championed by the Virginia Department of Transportation (VDOT) Traffic Engineering : Division, involved a thorough investigation of light-emitting diode (LED) roadway lighting technology by : testing six types of roadway luminaires (inclu...
White LED visible light communication technology research
NASA Astrophysics Data System (ADS)
Yang, Chao
2017-03-01
Visible light communication is a new type of wireless optical communication technology. White LED to the success of development, the LED lighting technology is facing a new revolution. Because the LED has high sensitivity, modulation, the advantages of good performance, large transmission power, can make it in light transmission light signal at the same time. Use white LED light-emitting characteristics, on the modulation signals to the visible light transmission, can constitute a LED visible light communication system. We built a small visible optical communication system. The system composition and structure has certain value in the field of practical application, and we also research the key technology of transmitters and receivers, the key problem has been resolved. By studying on the optical and LED the characteristics of a high speed modulation driving circuit and a high sensitive receiving circuit was designed. And information transmission through the single chip microcomputer test, a preliminary verification has realized the data transmission function.
Photoinduced RNA interference.
Matsushita-Ishiodori, Yuka; Ohtsuki, Takashi
2012-07-17
Because RNA interference (RNAi) can be applied to any gene, this technique has been widely used for studying gene functions. In addition, many researchers are attempting to use RNAi technology in RNAi-based therapies. However, several challenging and controversial issues have arisen during the widespread application of RNAi including target gene specificity, target cell specificity, and spatiotemporal control of gene silencing. To address these issues, several groups have utilized photochemistry to control the RNA release, both spatially and temporally. In this Account, we focus on recent studies using photocleavable protecting groups, photosensitizers, Hand gold nanoparticles for photoinduced RNAi. In 2005 the first report of photoinduced RNAi used a caged short interfering RNA (siRNA), an siRNA carrying a photocleavable protecting group. Caging groups block the bioactivities of target molecules, but allow for complete recovery of these functions via photoactivation. However, some RNAi activity can occur in these caged siRNAs, so it will be necessary to decrease this "leakage" and raise the RNAi activity restored after irradiation. This technique also uses UV light around 350 nm, which is cytotoxic, but in the near future we expect that it will be possible to use visible and near-infrared light We also examine the application of photochemical internalization (PCI) to RNAi technology, which involves a combination of photosensitizers and light. Instead of inducing RNAi using light, the strategy behind this method was to enhance RNAi using RNA carriers. Many wellknown RNA carriers deliver siRNAs into cells by endocytosis. The siRNAs are trapped in endocytic vesicles and have to be released into the cytoplasm in order to express their activity. To achieve the endosomal escape of siRNAs, PCI technology employed photosensitizers to generate light-dependent reactive oxygen species (ROS) that disrupted the endocytic vesicles. In most studies, RNAi-mediated knockdown of the target gene was detected even without PCI. Recently, a polymer capable of trapping the siRNA in endocytic vesicles controlled RNAi almost entirely by light. CLIP-RNAi uses photosensitizing carrier proteins that can be activated over a wide range of visible light wavelengths. With this method RNA carrier/siRNA complexes are completely trapped within endosomes, and RNAi is controlled strictly by light. Such precise, light-dependent control will open up new possibilities for cellular and molecular biology and therapy. Most recently, gold nanoparticles (AuNPs) conjugated to siRNA have provided temporal and spatial control of RNAi. The light-dependent melting of AuNPs accompanied by a shape transformation induces the release of thiolated siRNAs from AuNPs. In this method, the unique optical properties of the AuNP enable deep penetration of the excitation light into tissues at nearinfrared wavelengths. The development of photoinduced RNAi technology will lead to novel insights into gene functions and selective drug delivery, and many other scientific fields will continue to influence its progress.
Free Flight Rotorcraft Flight Test Vehicle Technology Development
NASA Technical Reports Server (NTRS)
Hodges, W. Todd; Walker, Gregory W.
1994-01-01
A rotary wing, unmanned air vehicle (UAV) is being developed as a research tool at the NASA Langley Research Center by the U.S. Army and NASA. This development program is intended to provide the rotorcraft research community an intermediate step between rotorcraft wind tunnel testing and full scale manned flight testing. The technologies under development for this vehicle are: adaptive electronic flight control systems incorporating artificial intelligence (AI) techniques, small-light weight sophisticated sensors, advanced telepresence-telerobotics systems and rotary wing UAV operational procedures. This paper briefly describes the system's requirements and the techniques used to integrate the various technologies to meet these requirements. The paper also discusses the status of the development effort. In addition to the original aeromechanics research mission, the technology development effort has generated a great deal of interest in the UAV community for related spin-off applications, as briefly described at the end of the paper. In some cases the technologies under development in the free flight program are critical to the ability to perform some applications.
Concept and design of the 2.0-m NGAT: the new generation of astronomical telescopes
NASA Astrophysics Data System (ADS)
Mansfield, Anthony G.
1998-08-01
The Royal Greenwich Observatory and Liverpool John Moores University, United Kingdom, have joined in a collaboration to produce high quality, ground based robotic telescopes (2.0 to 5.0 m), for use with optical, infrared and interferometric astronomy. This venture has taken the form of a commercial company, Telescope Technologies Limited, to produce the range of Alt-azimuth telescopes. The reliability of the low cost, advanced technology, telescope design will enable remote observing over the Internet. The first two telescopes, currently under production, will see first light in La Palma and India in 1999. This paper covers the concept, design and capability range of the NGAT telescopes.
NASA Astrophysics Data System (ADS)
Du, Zhidong; Chen, Chen; Pan, Liang
2017-04-01
Maskless lithography using parallel electron beamlets is a promising solution for next generation scalable maskless nanolithography. Researchers have focused on this goal but have been unable to find a robust technology to generate and control high-quality electron beamlets with satisfactory brightness and uniformity. In this work, we will aim to address this challenge by developing a revolutionary surface-plasmon-enhanced-photoemission (SPEP) technology to generate massively-parallel electron beamlets for maskless nanolithography. The new technology is built upon our recent breakthroughs in plasmonic lenses, which will be used to excite and focus surface plasmons to generate massively-parallel electron beamlets through photoemission. Specifically, the proposed SPEP device consists of an array of plasmonic lens and electrostatic micro-lens pairs, each pair independently producing an electron beamlet. During lithography, a spatial optical modulator will dynamically project light onto individual plasmonic lenses to control the switching and brightness of electron beamlets. The photons incident onto each plasmonic lens are concentrated into a diffraction-unlimited spot as localized surface plasmons to excite the local electrons to near their vacuum levels. Meanwhile, the electrostatic micro-lens extracts the excited electrons to form a focused beamlet, which can be rastered across a wafer to perform lithography. Studies showed that surface plasmons can enhance the photoemission by orders of magnitudes. This SPEP technology can scale up the maskless lithography process to write at wafers per hour. In this talk, we will report the mechanism of the strong electron-photon couplings and the locally enhanced photoexcitation, design of a SPEP device, overview of our proof-of-concept study, and demonstrated parallel lithography of 20-50 nm features.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kovalev, S.; Green, B.; Golz, T.
Here, understanding dynamics on ultrafast timescales enables unique and new insights into important processes in the materials and life sciences. In this respect, the fundamental pump-probe approach based on ultra-short photon pulses aims at the creation of stroboscopic movies. Performing such experiments at one of the many recently established accelerator-based 4th-generation light sources such as free-electron lasers or superradiant THz sources allows an enormous widening of the accessible parameter space for the excitation and/or probing light pulses. Compared to table-top devices, critical issues of this type of experiment are fluctuations of the timing between the accelerator and external laser systemsmore » and intensity instabilities of the accelerator-based photon sources. Existing solutions have so far been only demonstrated at low repetition rates and/or achieved a limited dynamic range in comparison to table-top experiments, while the 4th generation of accelerator-based light sources is based on superconducting radio-frequency technology, which enables operation at MHz or even GHz repetition rates. In this article, we present the successful demonstration of ultra-fast accelerator-laser pump-probe experiments performed at an unprecedentedly high repetition rate in the few-hundred-kHz regime and with a currently achievable optimal time resolution of 13 fs (rms). Our scheme, based on the pulse-resolved detection of multiple beam parameters relevant for the experiment, allows us to achieve an excellent sensitivity in real-world ultra-fast experiments, as demonstrated for the example of THz-field-driven coherent spin precession.« less
Stöcher, Markus; Leb, Victoria; Hölzl, Gabriele; Berg, Jörg
2002-12-01
The real-time PCR technology allows convenient detection and quantification of virus derived DNA. This approach is used in many PCR based assays in clinical laboratories. Detection and quantification of virus derived DNA is usually performed against external controls or external standards. Thus, adequacy within a clinical sample is not monitored for. This can be achieved using internal controls that are co-amplified with the specific target within the same reaction vessel. We describe a convenient way to prepare heterologous internal controls as competitors for real-time PCR based assays. The internal controls were devised as competitors in real-time PCR, e.g. LightCycler-PCR. The bacterial neomycin phosphotransferase gene (neo) was used as source for heterologous DNA. Within the neo gene a box was chosen containing sequences for four differently spaced forward primers, one reverse primer, and a pair of neo specific hybridization probes. Pairs of primers were constructed to compose of virus-specific primer sequences and neo box specific primer sequences. Using those composite primers in conventional preparative PCR four types of internal controls were amplified from the neo box and subsequently cloned. A panel of the four differently sized internal controls was generated and tested by LightCycler PCR using their virus-specific primers. All four different PCR products were detected with the single pair of neo specific FRET-hybridization probes. The presented approach to generate competitive internal controls for use in LightCycler PCR assays proved convenient und rapid. The obtained internal controls match most PCR product sizes used in clinical routine molecular assays and will assist to discriminate true from false negative results.
Kovalev, S.; Green, B.; Golz, T.; ...
2017-03-06
Here, understanding dynamics on ultrafast timescales enables unique and new insights into important processes in the materials and life sciences. In this respect, the fundamental pump-probe approach based on ultra-short photon pulses aims at the creation of stroboscopic movies. Performing such experiments at one of the many recently established accelerator-based 4th-generation light sources such as free-electron lasers or superradiant THz sources allows an enormous widening of the accessible parameter space for the excitation and/or probing light pulses. Compared to table-top devices, critical issues of this type of experiment are fluctuations of the timing between the accelerator and external laser systemsmore » and intensity instabilities of the accelerator-based photon sources. Existing solutions have so far been only demonstrated at low repetition rates and/or achieved a limited dynamic range in comparison to table-top experiments, while the 4th generation of accelerator-based light sources is based on superconducting radio-frequency technology, which enables operation at MHz or even GHz repetition rates. In this article, we present the successful demonstration of ultra-fast accelerator-laser pump-probe experiments performed at an unprecedentedly high repetition rate in the few-hundred-kHz regime and with a currently achievable optimal time resolution of 13 fs (rms). Our scheme, based on the pulse-resolved detection of multiple beam parameters relevant for the experiment, allows us to achieve an excellent sensitivity in real-world ultra-fast experiments, as demonstrated for the example of THz-field-driven coherent spin precession.« less
Progress of OLED devices with high efficiency at high luminance
NASA Astrophysics Data System (ADS)
Nguyen, Carmen; Ingram, Grayson; Lu, Zhenghong
2014-03-01
Organic light emitting diodes (OLEDs) have progressed significantly over the last two decades. For years, OLEDs have been promoted as the next generation technology for flat panel displays and solid-state lighting due to their potential for high energy efficiency and dynamic range of colors. Although high efficiency can readily be obtained at low brightness levels, a significant decline at high brightness is commonly observed. In this report, we will review various strategies for achieving highly efficient phosphorescent OLED devices at high luminance. Specifically, we will provide details regarding the performance and general working principles behind each strategy. We will conclude by looking at how some of these strategies can be combined to produce high efficiency white OLEDs at high brightness.
NASA Astrophysics Data System (ADS)
Xu, Chang-Qing; Gan, Yi; Sun, Jian
2012-03-01
Laser displays require red, green and blue (RGB) laser sources each with a low-cost, a high wall-plug efficiency, and a small size. However, semiconductor chips that directly emit green light with sufficient power and efficiency are not currently available on the market. A practical solution to the "green" bottleneck is to employ diode pumped solid state laser (DPSSL) technology, in which a frequency doubling crystal is used. In this paper, recent progress of MgO doped periodically poled lithium niobate (MgO:PPLN) frequency doubling optical chips will be presented. It is shown that MgO:PPLN can satisfy all of the requirements for laser displays and is ready for mass production.
Light scattering techniques for the characterization of optical components
NASA Astrophysics Data System (ADS)
Hauptvogel, M.; Schröder, S.; Herffurth, T.; Trost, M.; von Finck, A.; Duparré, A.; Weigel, T.
2017-11-01
The rapid developments in optical technologies generate increasingly higher and sometimes completely new demands on the quality of materials, surfaces, components, and systems. Examples for such driving applications are the steadily shrinking feature sizes in semiconductor lithography, nanostructured functional surfaces for consumer optics, and advanced optical systems for astronomy and space applications. The reduction of surface defects as well as the minimization of roughness and other scatter-relevant irregularities are essential factors in all these areas of application. Quality-monitoring for analysing and improving those properties must ensure that even minimal defects and roughness values can be detected reliably. Light scattering methods have a high potential for a non-contact, rapid, efficient, and sensitive determination of roughness, surface structures, and defects.
Sadick, Neil; Sorhaindo, Lian
2005-05-01
Radiofrequency (RF) and combined RF light source technologies have established themselves as safe and effective treatment modalities for several dermatologic procedures, including skin tightening, hair and leg vein removal, acne scarring, skin rejuvenation, and wrinkle reduction. This article reviews the technology, clinical applications, and recent advances of RF and combined RF light/laser source technologies in aesthetic medicine.
LightAssembler: fast and memory-efficient assembly algorithm for high-throughput sequencing reads.
El-Metwally, Sara; Zakaria, Magdi; Hamza, Taher
2016-11-01
The deluge of current sequenced data has exceeded Moore's Law, more than doubling every 2 years since the next-generation sequencing (NGS) technologies were invented. Accordingly, we will able to generate more and more data with high speed at fixed cost, but lack the computational resources to store, process and analyze it. With error prone high throughput NGS reads and genomic repeats, the assembly graph contains massive amount of redundant nodes and branching edges. Most assembly pipelines require this large graph to reside in memory to start their workflows, which is intractable for mammalian genomes. Resource-efficient genome assemblers combine both the power of advanced computing techniques and innovative data structures to encode the assembly graph efficiently in a computer memory. LightAssembler is a lightweight assembly algorithm designed to be executed on a desktop machine. It uses a pair of cache oblivious Bloom filters, one holding a uniform sample of [Formula: see text]-spaced sequenced [Formula: see text]-mers and the other holding [Formula: see text]-mers classified as likely correct, using a simple statistical test. LightAssembler contains a light implementation of the graph traversal and simplification modules that achieves comparable assembly accuracy and contiguity to other competing tools. Our method reduces the memory usage by [Formula: see text] compared to the resource-efficient assemblers using benchmark datasets from GAGE and Assemblathon projects. While LightAssembler can be considered as a gap-based sequence assembler, different gap sizes result in an almost constant assembly size and genome coverage. https://github.com/SaraEl-Metwally/LightAssembler CONTACT: sarah_almetwally4@mans.edu.egSupplementary information: Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
Light-emitting diode technology status and directions: Opportunities for horticultural lighting
Tsao, Jeffrey Y.; Pattison, P. Morgan; Krames, Michael R.
2016-01-01
Here, light-emitting diode (LED) technology has advanced rapidly over the last decade, primarily driven by display and general illumination applications ("solid-state lighting (SSL) for humans"). These advancements have made LED lighting technically and economically advantageous not only for these applications, but also, as an indirect benefit, for adjacent applications such as horticultural lighting ("SSL for plants"). Moreover, LED technology has much room for continued improvement. In the near-term, these improvements will continue to be driven by SSL for humans (with indirect benefit to SSL for plants), the most important of which can be anticipated.
A visible light-curable yet visible wavelength-transparent resin for stereolithography 3D printing
NASA Astrophysics Data System (ADS)
Park, Hong Key; Shin, Mikyung; Kim, Bongkyun; Park, Jin Woo; Lee, Haeshin
2018-04-01
Herein, a new polymeric resin for stereolithography (SLA) three-dimensional printing (SLA-3DP) is reported. An ultraviolet (UV) or visible (VIS) light source is critical for SLA printing technology. UV light can be used to manufacture 3D objects in SLA-3DP, but there are significant occupational safety and health issues (particularly for eyes). These issues prevent the widespread use of SLA-3DP at home or in the office. Through the use of VIS light, the safety and health issues can largely be solved, but only non-transparent 3D objects can be manufactured, which prevents the application of 3DP to the production of various common transparent consumer products. For these reasons, we developed a VIS light-curable yet visibly transparent resin for SLA-3DP, which also retains UV curability. The key was to identify the photoinitiator diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (DPTBP). DPTBP was originally designed as a UV photoinitiator, but we found that VIS light irradiation is sufficient to split DPTBP and generate radicals due to its slight VIS light absorption up to 420 nm. The cured resin displays high transparency and beautiful transparent colors by incorporating various dyes; additionally, its mechanical properties are superior to those of commercial resins (Arario 410) and photoinitiators (Irgacure 2959).
Effective Light Directed Assembly of Building Blocks with Microscale Control.
Dinh, Ngoc-Duy; Luo, Rongcong; Christine, Maria Tankeh Asuncion; Lin, Weikang Nicholas; Shih, Wei-Chuan; Goh, James Cho-Hong; Chen, Chia-Hung
2017-06-01
Light-directed forces have been widely used to pattern micro/nanoscale objects with precise control, forming functional assemblies. However, a substantial laser intensity is required to generate sufficient optical gradient forces to move a small object in a certain direction, causing limited throughput for applications. A high-throughput light-directed assembly is demonstrated as a printing technology by introducing gold nanorods to induce thermal convection flows that move microparticles (diameter = 40 µm to several hundreds of micrometers) to specific light-guided locations, forming desired patterns. With the advantage of effective light-directed assembly, the microfluidic-fabricated monodispersed biocompatible microparticles are used as building blocks to construct a structured assembly (≈10 cm scale) in ≈2 min. The control with microscale precision is approached by changing the size of the laser light spot. After crosslinking assembly of building blocks, a novel soft material with wanted pattern is approached. To demonstrate its application, the mesenchymal stem-cell-seeded hydrogel microparticles are prepared as functional building blocks to construct scaffold-free tissues with desired structures. This light-directed fabrication method can be applied to integrate different building units, enabling the bottom-up formation of materials with precise control over their internal structure for bioprinting, tissue engineering, and advanced manufacturing. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Performance of 100-W HVM LPP-EUV source
NASA Astrophysics Data System (ADS)
Mizoguchi, Hakaru; Nakarai, Hiroaki; Abe, Tamotsu; Nowak, Krzysztof M.; Kawasuji, Yasufumi; Tanaka, Hiroshi; Watanabe, Yukio; Hori, Tsukasa; Kodama, Takeshi; Shiraishi, Yutaka; Yanagida, Tatsuya; Soumagne, Georg; Yamada, Tsuyoshi; Yamazaki, Taku; Okazaki, Shinji; Saitou, Takashi
2015-08-01
At Gigaphoton Inc., we have developed unique and original technologies for a carbon dioxide laser-produced tin plasma extreme ultraviolet (CO2-Sn-LPP EUV) light source, which is the most promising solution for high-power high-volume manufacturing (HVM) EUV lithography at 13.5 nm. Our unique technologies include the combination of a pulsed CO2 laser with Sn droplets, the application of dual-wavelength laser pulses for Sn droplet conditioning, and subsequent EUV generation and magnetic field mitigation. Theoretical and experimental data have clearly shown the advantage of our proposed strategy. Currently, we are developing the first HVM light source, `GL200E'. This HVM light source will provide 250-W EUV power based on a 20-kW level pulsed CO2 laser. The preparation of a high average-power CO2 laser (more than 20 kW output power) has been completed in cooperation with Mitsubishi Electric Corporation. Recently, we achieved 140 W at 50 kHz and 50% duty cycle operation as well as 2 h of operation at 100 W of power level. Further improvements are ongoing. We will report the latest status and the challenge to reach stable system operation of more than 100 W at about 4% conversion efficiency with 20-μm droplets and magnetic mitigation.
Applications of Fluorogens with Rotor Structures in Solar Cells.
Ong, Kok-Haw; Liu, Bin
2017-05-29
Solar cells are devices that convert light energy into electricity. To drive greater adoption of solar cell technologies, higher cell efficiencies and reductions in manufacturing cost are necessary. Fluorogens containing rotor structures may be helpful in addressing some of these challenges due to their unique twisted structures and photophysics. In this review, we discuss the applications of rotor-containing molecules as dyes for luminescent down-shifting layers and luminescent solar concentrators, where their aggregation-induced emission properties and large Stokes shifts are highly desirable. We also discuss the applications of molecules containing rotors in third-generation solar cell technologies, namely dye-sensitized solar cells and organic photovoltaics, where the twisted 3-dimensional rotor structures are used primarily for aggregation control. Finally, we discuss perspectives on the future role of molecules containing rotor structures in solar cell technologies.
Kozai, Takashi D.Y.; Vazquez, Alberto L.
2015-01-01
Bioelectronics, electronic technologies that interface with biological systems, are experiencing rapid growth in terms of technology development and applications, especially in neuroscience and neuroprosthetic research. The parallel growth with optogenetics and in vivo multi-photon microscopy has also begun to generate great enthusiasm for simultaneous applications with bioelectronic technologies. However, emerging research showing artefact contaminated data highlight the need for understanding the fundamental physical principles that critically impact experimental results and complicate their interpretation. This review covers four major topics: 1) material dependent properties of the photoelectric effect (conductor, semiconductor, organic, photoelectric work function (band gap)); 2) optic dependent properties of the photoelectric effect (single photon, multiphoton, entangled biphoton, intensity, wavelength, coherence); 3) strategies and limitations for avoiding/minimizing photoelectric effects; and 4) advantages of and applications for light-based bioelectronics (photo-bioelectronics). PMID:26167283
Object-oriented recognition of high-resolution remote sensing image
NASA Astrophysics Data System (ADS)
Wang, Yongyan; Li, Haitao; Chen, Hong; Xu, Yuannan
2016-01-01
With the development of remote sensing imaging technology and the improvement of multi-source image's resolution in satellite visible light, multi-spectral and hyper spectral , the high resolution remote sensing image has been widely used in various fields, for example military field, surveying and mapping, geophysical prospecting, environment and so forth. In remote sensing image, the segmentation of ground targets, feature extraction and the technology of automatic recognition are the hotspot and difficulty in the research of modern information technology. This paper also presents an object-oriented remote sensing image scene classification method. The method is consist of vehicles typical objects classification generation, nonparametric density estimation theory, mean shift segmentation theory, multi-scale corner detection algorithm, local shape matching algorithm based on template. Remote sensing vehicles image classification software system is designed and implemented to meet the requirements .
DOE Office of Scientific and Technical Information (OSTI.GOV)
D.M. McEligot; K. G. Condie; G. E. McCreery
2005-10-01
Background: The ultimate goal of the study is the improvement of predictive methods for safety analyses and design of Generation IV reactor systems such as supercritical water reactors (SCWR) for higher efficiency, improved performance and operation, design simplification, enhanced safety and reduced waste and cost. The objective of this Korean / US / laboratory / university collaboration of coupled fundamental computational and experimental studies is to develop the supporting knowledge needed for improved predictive techniques for use in the technology development of Generation IV reactor concepts and their passive safety systems. The present study emphasizes SCWR concepts in the Generationmore » IV program.« less
Selective THz control of magnetic order: new opportunities from superradiant undulator sources
NASA Astrophysics Data System (ADS)
Kovalev, S.; Wang, Zhe; Deinert, J.-C.; Awari, N.; Chen, M.; Green, B.; Germanskiy, S.; de Oliveira, T. V. A. G.; Lee, J. S.; Deac, A.; Turchinovich, D.; Stojanovic, N.; Eisebitt, S.; Radu, I.; Bonetti, S.; Kampfrath, T.; Gensch, M.
2018-03-01
Recent advancements of accelerator technology enable the generation of carrier-envelope-phase stable THz pulses with high fields at adjustable high repetition rates. The appropriate choice of THz radiator allows generation of narrow-band, spectrally dense, multicycle THz transients of tunable THz frequency which are ideally suited to selectively excite low-energy excitations such as magnons or phonons. They also allow one to study the frequency dependence of nonresonant THz-field interactions with various order parameters with high dynamic range. In this paper, we discuss the future prospects of this new type of THz light source for studying the coherent control of magnetic order based on recent results.
NASA Astrophysics Data System (ADS)
Hellrigel, Mary Ann
This dissertation is a social, business, and technological history of electrification in the United States. It examines the origins of the electric utility industry, the development of light, heat and power technology, the marketing of electric service, and the adoption of electricity and domestic appliances in the late nineteenth and early twentieth centuries in two communities: Harrisburg and West Chester, Pennsylvania. Beginning in the 1880s, manufactured gas and electric utilities waged an intense and lengthy battle for the urban energy marketplace. Many villages, small towns and big cities had multiple gas and electric companies, driving technological change as they worked to increase reliability, lower costs, and improve lamps, lighting fixtures, and appliances. Producers as well as consumers grappled with these new sources of energy, looking for profitable and practical ways to incorporate them into everyday life. Gas and utility executives, locked in head-to-head competition, realized that marketing their invisible product was an uncertain process. Utilities redefined the concepts of "tradition" and "modernity" to attract investors and offer appliances and installation in addition to selling energy. Upper and middle class households seeking a modern comfortable home could use gas or electricity (and often both), while working classes made do with kerosene, coal and wood. Mixed technologies, based on consumer preference, access, product availability, price, and service greatly influenced the creation of "modern" America. Initially, Pennsylvania law mandated local energy systems-electricity and gas had to be consumed within the same town. Only in the early twentieth century were these laws amended to permit inter-connections, allowing merger and consolidation of utilities to serve a wider geographic area. By the 1910s, law, technology, and capital made it possible to abandon local central stations. In only a few decades, the industry shifted from locally-owned small scale generation plants to larger regional systems capable of long distance transmission and directed by a cadre of engineering, financial, and managerial experts. In 1928, Harrisburg's electric utility merged into the Pennsylvania Power & Light Company and the next year West Chester's electric and gas companies became part of the Philadelphia Electric Company, marking the beginning of a new era.
European road lighting technologies
DOT National Transportation Integrated Search
2001-09-01
The objective of this scanning tour was to gather information from European transportation ministries and lighting professionals regarding cutting-edge research and technologies in highway and roadway lighting systems, including tunnel illumination, ...
NASA Astrophysics Data System (ADS)
Franken, R. H.-J.
2006-09-01
With the growing population and the increasing environmental problems of the 'common' fossil and nuclear energy production, the need for clean and sustainable energy sources is evident. Solar energy conversion, such as in photovoltaic (PV) systems, can play a major role in the urgently needed energy transition in electricity production. At the present time PV module production is dominated by the crystalline wafer technology. Thin film silicon technology is an alternative solar energy technology that operates at lower efficiencies, however, it has several significant advantages, such as the possibility of deposition on cheap (flexible) substrates and the much smaller silicon material consumption. Because of the small thickness of the solar cells, light trapping schemes are needed in order to obtain enough light absorption and current generation. This thesis describes the research on thin film silicon solar cells with the focus on the optimization of the transparent conducting oxide (TCO) layers and textured metal Ag substrate layers for the use as enhanced light scattering back reflectors in n-i-p type of solar cells. First we analyzed ZnO:Al (TCO) layers deposited in an radio frequent (rf) magnetron deposition system equipped with a 7 inch target. We have focused on the improvement of the electrical properties without sacrificing the optical properties by increasing the mobility and decreasing the grain boundary density. Furthermore, we described some of the effects on light trapping of ZnO:Al enhanced back reflectors. The described effects are able to explain the observed experimental data. Furthermore, we present a relation between the surface morphology of the Ag back contact and the current enhancement in microcrystalline (muc-Si:H) solar cells. We show the importance of the lateral feature sizes of the Ag surface on the light scattering and introduce a method to characterize the quality of the back reflector by combining the vertical and lateral feature sizes at this surface. Additionally, we show that we can control the lateral feature sizes and obtain an optimized roughness for light scattering. With this new knowledge we were able to indicate the influence of the surface plasmon absorption of the textured Ag layers on the current enhancement and recognize this effect as one of the limiting factors to the current increase in thin film solar cells. Finally we present the dark and light current voltage (J-V) parameters of muc-Si:H solar cells as a function of the rms roughness of the substrate. We show that increased roughness can result in an increased defect density of the absorbing silicon layer (i layer), which limits the current collection in the solar cell. The presented research gives better understanding of the effect of TCOs and textured interfaces on light trapping and current enhancement in thin film silicon solar cells. The thesis explains some fundamental insights in light scattering and reveals some material and morphology features that are dominantly limiting the current generation in muc-Si:H solar cells deposited on light scattering back reflectors. Furthermore, it presents a method to obtain optimized back scattering contacts at deposition temperatures below 300 oC, which opens the possibility for the use of heat resistant plastic substrates. We improved the muc-Si:H solar cell efficiency with flat back reflectors from 4.5 % and 14.6 mA/cm2 to 8.5 % and 23.4 mA/cm2 with the use of optimized back reflectors.
The need for lighting education
NASA Astrophysics Data System (ADS)
Julian, Warren G.
2002-05-01
It is amazing that in a world now dominated by light - a world that is absolutely dependent upon light - that there is almost no lighting education. In a few countries of the world there exist tertiary level lighting programs but these can be counted on the fingers of two hands. Developments in lighting technology have produced a range of design tools that can lead to improved and energy-efficient lighting. However, most of this technology is 'harder' to use than traditional technology, emphasizing the need for not only improved lighting education but for its initiation. This paper discusses the need for education and uses the example of the University of Sydney program as a possible basis for others to use. It also examines how it is being delivered in Singapore.
Molecular diodes in optical rectennas
NASA Astrophysics Data System (ADS)
Duché, David; Palanchoke, Ujwol; Terracciano, Luigi; Dang, Florian-Xuan; Patrone, Lionel; Le Rouzo, Judikael; Balaban, Téodore Silviu; Alfonso, Claude; Charai, Ahmed; Margeat, Olivier; Ackermann, Jorg; Gourgon, Cécile; Simon, Jean-Jacques; Escoubas, Ludovic
2016-09-01
The photo conversion efficiencies of the 1st and 2nd generat ion photovoltaic solar cells are limited by the physical phenomena involved during the photo-conversion processes. An upper limit around 30% has been predicted for a monojunction silicon solar cell. In this work, we study 3rd generation solar cells named rectenna which could direct ly convert visible and infrared light into DC current. The rectenna technology is at odds with the actual photovoltaic technologies, since it is not based on the use of semi-conducting materials. We study a rectenna architecture consist ing of plasmonic nano-antennas associated with rectifying self assembled molecular diodes. We first opt imized the geometry of plasmonic nano-antennas using an FDTD method. The optimal antennas are then realized using a nano-imprint process and associated with self assembled molecular diodes in 11- ferrocenyl-undecanethiol. Finally, The I(V) characterist ics in darkness of the rectennas has been carried out using an STM. The molecular diodes exhibit averaged rect ification ratios of 5.
NASA Astrophysics Data System (ADS)
Zhang, Xueliang; Meng, Zhou; Hu, Zhengliang; Yang, Huayong; Song, Zhangqi; Hu, Yongming
2008-12-01
A polarization maintaining fiber (PMF) magnetic field sensor based on a digital phase generated carrier (PGC) technology is presented. A magnetic sensor constructed with two magnetostrictive strips attached on the sensing fiber is joined in the sensing arm of a fiber Michelson interferometer. The fiber optic interferometric system is made of all PMF, which inhibits the polarization-induced signal fading. The light source is a fiber laser which can be modulated directly. The PGC metnod is used to demodulate magnetic field signal avoiding phase induced interferometric signal fading, and ensure the sensing partto be all fiber structure. A fiber optic magnetic field sensor with appreciate size for the fiber optic hydrophone towed array is obtained, which can be used to sense the enviromental magnetic field along the sensing direction.This sensor is a good choice for the directional angle measurement through sensing the Earth magnetic field in the array shape measurement of a fiber optic hydrophone towed array.
NASA Astrophysics Data System (ADS)
Bechis, K.; Pitruzzello, A.
2014-09-01
This presentation describes our ongoing research into using a ground-based light field camera to obtain passive, single-aperture 3D imagery of LEO objects. Light field cameras are an emerging and rapidly evolving technology for passive 3D imaging with a single optical sensor. The cameras use an array of lenslets placed in front of the camera focal plane, which provides angle of arrival information for light rays originating from across the target, allowing range to target and 3D image to be obtained from a single image using monocular optics. The technology, which has been commercially available for less than four years, has the potential to replace dual-sensor systems such as stereo cameras, dual radar-optical systems, and optical-LIDAR fused systems, thus reducing size, weight, cost, and complexity. We have developed a prototype system for passive ranging and 3D imaging using a commercial light field camera and custom light field image processing algorithms. Our light field camera system has been demonstrated for ground-target surveillance and threat detection applications, and this paper presents results of our research thus far into applying this technology to the 3D imaging of LEO objects. The prototype 3D imaging camera system developed by Northrop Grumman uses a Raytrix R5 C2GigE light field camera connected to a Windows computer with an nVidia graphics processing unit (GPU). The system has a frame rate of 30 Hz, and a software control interface allows for automated camera triggering and light field image acquisition to disk. Custom image processing software then performs the following steps: (1) image refocusing, (2) change detection, (3) range finding, and (4) 3D reconstruction. In Step (1), a series of 2D images are generated from each light field image; the 2D images can be refocused at up to 100 different depths. Currently, steps (1) through (3) are automated, while step (4) requires some user interaction. A key requirement for light field camera operation is that the target must be within the near-field (Fraunhofer distance) of the collecting optics. For example, in visible light the near-field of a 1-m telescope extends out to about 3,500 km, while the near-field of the AEOS telescope extends out over 46,000 km. For our initial proof of concept, we have integrated our light field camera with a 14-inch Meade LX600 advanced coma-free telescope, to image various surrogate ground targets at up to tens of kilometers range. Our experiments with the 14-inch telescope have assessed factors and requirements that are traceable and scalable to a larger-aperture system that would have the near-field distance needed to obtain 3D images of LEO objects. The next step would be to integrate a light field camera with a 1-m or larger telescope and evaluate its 3D imaging capability against LEO objects. 3D imaging of LEO space objects with light field camera technology can potentially provide a valuable new tool for space situational awareness, especially for those situations where laser or radar illumination of the target objects is not feasible.
Living on the Edge: Re-shaping the Interface of Synthetic Biology and Nanotechnology.
Wu, Shang-Jung; Boghossian, Ardemis A
2016-11-30
A new team of researchers at EPFL is taking an 'anti-disciplinary' approach to creating optical devices. These devices take advantage of the synergy in tuning both nano- and bio-material properties, coupling the advantages of two growing, albeit traditionally distinct, fields. With applications spanning from biosensing and microarray assays to living photovoltaics, the Laboratory of NanoBiotechnology (LNB) is uncovering an unexplored space for the next generation of chemical analytics and light-harvesting technologies.
Anthropometric considerations for a 4-axis side-arm flight controller
NASA Technical Reports Server (NTRS)
Debellis, W. B.
1986-01-01
A data base on multiaxis side-arm flight controls was generated. The rapid advances in fly-by-light technology, automatic stability systems, and onboard computers have combined to create flexible flight control systems which could reduce the workload imposed on the operator by complex new equipment. This side-arm flight controller combines four controls into one unit and should simplify the pilot's task. However, the use of a multiaxis side-arm flight controller without complete cockpit integration may tend to increase the pilot's workload.
3D Printing of Conductive Complex Structures with In Situ Generation of Silver Nanoparticles.
Fantino, Erika; Chiappone, Annalisa; Roppolo, Ignazio; Manfredi, Diego; Bongiovanni, Roberta; Pirri, Candido Fabrizio; Calignano, Flaviana
2016-05-01
Coupling the photoreduction of a metal precursor with 3D-printing technology is shown to allow the fabrication of conductive 3D hybrid structures consisting of metal nanoparticles and organic polymers shaped in complex multilayered architectures. 3D conductive structures are fabricated incorporating silver nitrate into a photocurable oligomer in the presence of suitable photoinitiators and exposing them to a digital light system. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Finite element analysis of a micromechanical deformable mirror device
NASA Technical Reports Server (NTRS)
Sheerer, T. J.; Nelson, W. E.; Hornbeck, L. J.
1989-01-01
A monolithic spatial light modulator chip was developed consisting of a large number of micrometer-scale mirror cells which can be rotated through an angle by application of an electrostatic field. The field is generated by electronics integral to the chip. The chip has application in photoreceptor based non-impact printing technologies. Chips containing over 16000 cells were fabricated, and were tested to several billions of cycles. Finite Element Analysis (FEA) of the device was used to model both the electrical and mechanical characteristics.
Plasmonic Sensor Based on Dielectric Nanoprisms
NASA Astrophysics Data System (ADS)
Elshorbagy, Mahmoud H.; Cuadrado, Alexander; Alda, Javier
2017-11-01
A periodic array of extruded nanoprisms is proposed to generate surface plasmon resonances for sensing applications. Nanoprisms guide and funnel light towards the metal-dielectric interface where the dielectric acts as the medium under test. The system works under normal incidence conditions and is spectrally interrogated. The performance is better than the classical Kretschmann configurations, and the values of sensitivity and figure of merit are competitive with other plasmonic sensor technologies. The geometry and the choice of materials have been made taking into account applicable fabrication constraints.
A cross-platform solution for light field based 3D telemedicine.
Wang, Gengkun; Xiang, Wei; Pickering, Mark
2016-03-01
Current telehealth services are dominated by conventional 2D video conferencing systems, which are limited in their capabilities in providing a satisfactory communication experience due to the lack of realism. The "immersiveness" provided by 3D technologies has the potential to promote telehealth services to a wider range of applications. However, conventional stereoscopic 3D technologies are deficient in many aspects, including low resolution and the requirement for complicated multi-camera setup and calibration, and special glasses. The advent of light field (LF) photography enables us to record light rays in a single shot and provide glasses-free 3D display with continuous motion parallax in a wide viewing zone, which is ideally suited for 3D telehealth applications. As far as our literature review suggests, there have been no reports of 3D telemedicine systems using LF technology. In this paper, we propose a cross-platform solution for a LF-based 3D telemedicine system. Firstly, a novel system architecture based on LF technology is established, which is able to capture the LF of a patient, and provide an immersive 3D display at the doctor site. For 3D modeling, we further propose an algorithm which is able to convert the captured LF to a 3D model with a high level of detail. For the software implementation on different platforms (i.e., desktop, web-based and mobile phone platforms), a cross-platform solution is proposed. Demo applications have been developed for 2D/3D video conferencing, 3D model display and edit, blood pressure and heart rate monitoring, and patient data viewing functions. The demo software can be extended to multi-discipline telehealth applications, such as tele-dentistry, tele-wound and tele-psychiatry. The proposed 3D telemedicine solution has the potential to revolutionize next-generation telemedicine technologies by providing a high quality immersive tele-consultation experience. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
NASA Technical Reports Server (NTRS)
Smith, David D.
2015-01-01
Next-generation space missions are currently constrained by existing spacecraft navigation systems which are not fully autonomous. These systems suffer from accumulated dead-reckoning errors and must therefore rely on periodic corrections provided by supplementary technologies that depend on line-of-sight signals from Earth, satellites, or other celestial bodies for absolute attitude and position determination, which can be spoofed, incorrectly identified, occluded, obscured, attenuated, or insufficiently available. These dead-reckoning errors originate in the ring laser gyros themselves, which constitute inertial measurement units. Increasing the time for standalone spacecraft navigation therefore requires fundamental improvements in gyroscope technologies. One promising solution to enhance gyro sensitivity is to place an anomalous dispersion or fast light material inside the gyro cavity. The fast light essentially provides a positive feedback to the gyro response, resulting in a larger measured beat frequency for a given rotation rate as shown in figure 1. Game Changing Development has been investing in this idea through the Fast Light Optical Gyros (FLOG) project, a collaborative effort which began in FY 2013 between NASA Marshall Space Flight Center (MSFC), the U.S. Army Aviation and Missile Research, Development, and Engineering Center (AMRDEC), and Northwestern University. MSFC and AMRDEC are working on the development of a passive FLOG (PFLOG), while Northwestern is developing an active FLOG (AFLOG). The project has demonstrated new benchmarks in the state of the art for scale factor sensitivity enhancement. Recent results show cavity scale factor enhancements of approx.100 for passive cavities.
Point to point multispectral light projection applied to cultural heritage
NASA Astrophysics Data System (ADS)
Vázquez, D.; Alvarez, A.; Canabal, H.; Garcia, A.; Mayorga, S.; Muro, C.; Galan, T.
2017-09-01
Use of new of light sources based on LED technology should allow the develop of systems that combine conservation and exhibition requirements and allow to make these art goods available to the next generations according to sustainability principles. The goal of this work is to develop light systems and sources with an optimized spectral distribution for each specific point of the art piece. This optimization process implies to maximize the color fidelity reproduction and the same time to minimize the photochemical damage. Perceived color under these sources will be similar (metameric) to technical requirements given by the restoration team uncharged of the conservation and exhibition of the goods of art. Depending of the fragility of the exposed art objects (i.e. spectral responsivity of the material) the irradiance must be kept under a critical level. Therefore, it is necessary to develop a mathematical model that simulates with enough accuracy both the visual effect of the illumination and the photochemical impact of the radiation. Spectral reflectance of a reference painting The mathematical model is based on a merit function that optimized the individual intensity of the LED-light sources taking into account the damage function of the material and color space coordinates. Moreover the algorithm used weights for damage and color fidelity in order to adapt the model to a specific museal application. In this work we show a sample of this technology applied to a picture of Sorolla (1863-1923) an important Spanish painter title "woman walking at the beach".
Energetic Combustion Devices for Aerospace Propulsion and Power
NASA Technical Reports Server (NTRS)
Litchford, Ron J.
2000-01-01
Chemical reactions have long been the mainstay thermal energy source for aerospace propulsion and power. Although it is widely recognized that the intrinsic energy density limitations of chemical bonds place severe constraints on maximum realizable performance, it will likely be several years before systems based on high energy density nuclear fuels can be placed into routine service. In the mean time, efforts to develop high energy density chemicals and advanced combustion devices which can utilize such energetic fuels may yield worthwhile returns in overall system performance and cost. Current efforts in this vein are being carried out at NASA MSFC under the direction of the author in the areas of pulse detonation engine technology development and light metals combustion devices. Pulse detonation engines are touted as a low cost alternative to gas turbine engines and to conventional rocket engines, but actual performance and cost benefits have yet to be convincingly demonstrated. Light metal fueled engines also offer potential benefits in certain niche applications such as aluminum/CO2 fueled engines for endo-atmospheric Martian propulsion. Light metal fueled MHD generators also present promising opportunities with respect to electric power generation for electromagnetic launch assist. This presentation will discuss the applications potential of these concepts with respect to aero ace propulsion and power and will review the current status of the development efforts.
NASA Astrophysics Data System (ADS)
Olsen, M. K.
2018-03-01
The development of quantum technologies which use quantum states of the light field interacting with other systems creates a demand for such states over wide frequency ranges. In this work we compare the bipartite entanglement and Einstein-Podolsky-Rosen (EPR) -steering properties of the two different parametric schemes which produce third-harmonic optical fields from an input field at the fundamental frequency. The first scheme uses second harmonic cascaded with sum-frequency generation, while the second uses triply degenerate four- wave mixing, also known as direct third-harmonic generation. We find that both schemes produce continuous-variable bipartite entanglement and EPR steering over a frequency range which has previously been unobtainable. The direct scheme produces a greater degree of EPR steering, while the cascaded scheme allows for greater flexibility in having three available bipartitions, thus allowing for greater flexibility in the tailoring of light matter interfaces. There are also parameter regimes in both for which classical mean-field analyses fail to predict the mean-field solutions. Both schemes may be very useful for applications in quantum communication and computation networks, as well as providing for quantum interfaces between a wider range of light and atomic ensembles than is presently practicable.
Henry, Kevin A
2018-01-01
Immunogenetic analyses of expressed antibody repertoires are becoming increasingly common experimental investigations and are critical to furthering our understanding of autoimmunity, infectious disease, and cancer. Next-generation DNA sequencing (NGS) technologies have now made it possible to interrogate antibody repertoires to unprecedented depths, typically by sequencing of cDNAs encoding immunoglobulin variable domains. In this chapter, we describe simple, fast, and reliable methods for producing and sequencing multiplex PCR amplicons derived from the variable regions (V H , V H H or V L ) of rearranged immunoglobulin heavy and light chain genes using the Illumina MiSeq platform. We include complete protocols and primer sets for amplicon sequencing of V H /V H H/V L repertoires directly from human, mouse, and llama lymphocytes as well as from phage-displayed V H /V H H/V L libraries; these can be easily be adapted to other types of amplicons with little modification. The resulting amplicons are diverse and representative, even using as few as 10 3 input B cells, and their generation is relatively inexpensive, requiring no special equipment and only a limited set of primers. In the absence of heavy-light chain pairing, single-domain antibodies are uniquely amenable to NGS analyses. We present a number of applications of NGS technology useful in discovery of single-domain antibodies from phage display libraries, including: (i) assessment of library functionality; (ii) confirmation of desired library randomization; (iii) estimation of library diversity; and (iv) monitoring the progress of panning experiments. While the case studies presented here are of phage-displayed single-domain antibody libraries, the principles extend to other types of in vitro display libraries.
Roadmap on optical energy conversion
NASA Astrophysics Data System (ADS)
Boriskina, Svetlana V.; Green, Martin A.; Catchpole, Kylie; Yablonovitch, Eli; Beard, Matthew C.; Okada, Yoshitaka; Lany, Stephan; Gershon, Talia; Zakutayev, Andriy; Tahersima, Mohammad H.; Sorger, Volker J.; Naughton, Michael J.; Kempa, Krzysztof; Dagenais, Mario; Yao, Yuan; Xu, Lu; Sheng, Xing; Bronstein, Noah D.; Rogers, John A.; Alivisatos, A. Paul; Nuzzo, Ralph G.; Gordon, Jeffrey M.; Wu, Di M.; Wisser, Michael D.; Salleo, Alberto; Dionne, Jennifer; Bermel, Peter; Greffet, Jean-Jacques; Celanovic, Ivan; Soljacic, Marin; Manor, Assaf; Rotschild, Carmel; Raman, Aaswath; Zhu, Linxiao; Fan, Shanhui; Chen, Gang
2016-07-01
For decades, progress in the field of optical (including solar) energy conversion was dominated by advances in the conventional concentrating optics and materials design. In recent years, however, conceptual and technological breakthroughs in the fields of nanophotonics and plasmonics combined with a better understanding of the thermodynamics of the photon energy-conversion processes reshaped the landscape of energy-conversion schemes and devices. Nanostructured devices and materials that make use of size quantization effects to manipulate photon density of states offer a way to overcome the conventional light absorption limits. Novel optical spectrum splitting and photon-recycling schemes reduce the entropy production in the optical energy-conversion platforms and boost their efficiencies. Optical design concepts are rapidly expanding into the infrared energy band, offering new approaches to harvest waste heat, to reduce the thermal emission losses, and to achieve noncontact radiative cooling of solar cells as well as of optical and electronic circuitries. Light-matter interaction enabled by nanophotonics and plasmonics underlie the performance of the third- and fourth-generation energy-conversion devices, including up- and down-conversion of photon energy, near-field radiative energy transfer, and hot electron generation and harvesting. Finally, the increased market penetration of alternative solar energy-conversion technologies amplifies the role of cost-driven and environmental considerations. This roadmap on optical energy conversion provides a snapshot of the state of the art in optical energy conversion, remaining challenges, and most promising approaches to address these challenges. Leading experts authored 19 focused short sections of the roadmap where they share their vision on a specific aspect of this burgeoning research field. The roadmap opens up with a tutorial section, which introduces major concepts and terminology. It is our hope that the roadmap will serve as an important resource for the scientific community, new generations of researchers, funding agencies, industry experts, and investors.
Liquid Crystal Spatial Light Modulators for Simulating Zonal Multifocal Lenses.
Li, Yiyu; Bradley, Arthur; Xu, Renfeng; Kollbaum, Pete S
2017-09-01
To maximize efficiency of the normally lengthy and costly multizone lens design and testing process, it is advantageous to evaluate the potential efficacy of a design as thoroughly as possible prior to lens fabrication and on-eye testing. The current work describes an ex vivo approach of optical design testing. The aim of this study was to describe a system capable of examining the optical characteristics of multizone bifocal and multifocal optics by subaperture stitching using liquid crystal technologies. A liquid crystal spatial light modulator (SLM) was incorporated in each of two channels to generate complementary subapertures by amplitude modulation. Additional trial lenses and phase plates were placed in pupil conjugate planes of either channel to integrate the desired bifocal and multifocal optics once the two optical paths were recombined. A high-resolution Shack-Hartmann aberrometer was integrated to measure the optics of the dual-channel system. Power and wavefront error maps as well as point spread functions were measured and computed for each of three multizone multifocal designs. High transmission modulation was achieved by introducing half-wavelength optical path differences to create two- and five-zone bifocal apertures. Dual-channel stitching revealed classic annular rings in the point spread functions generated from two-zone designs when the outer annular optic was defocused. However, low efficiency of the SLM prevented us from simultaneously measuring the eye + simulator aberrations, and the higher-order diffraction patterns generated by the cellular structure of the liquid crystal arrays limited the visual field to ±0.45 degrees. The system successfully simulated bifocal and multifocal simultaneous lenses allowing for future evaluation of both objective and subjective evaluation of complex optical designs. However, low efficiency and diffraction phenomena of the SLM limit the utility of this technology for simulating multizone and multifocal optics.
Efficient Multiphoton Generation in Waveguide Quantum Electrodynamics.
González-Tudela, A; Paulisch, V; Kimble, H J; Cirac, J I
2017-05-26
Engineering quantum states of light is at the basis of many quantum technologies such as quantum cryptography, teleportation, or metrology among others. Though, single photons can be generated in many scenarios, the efficient and reliable generation of complex single-mode multiphoton states is still a long-standing goal in the field, as current methods either suffer from low fidelities or small probabilities. Here we discuss several protocols which harness the strong and long-range atomic interactions induced by waveguide QED to efficiently load excitations in a collection of atoms, which can then be triggered to produce the desired multiphoton state. In order to boost the success probability and fidelity of each excitation process, atoms are used to both generate the excitations in the rest, as well as to herald the successful generation. Furthermore, to overcome the exponential scaling of the probability of success with the number of excitations, we design a protocol to merge excitations that are present in different internal atomic levels with a polynomial scaling.
TOWARD THE DEVELOPMENT OF A CONSENSUS MATERIALS DATABASE FOR PRESSURE TECHNOLGY APPLICATIONS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Swindeman, Robert W; Ren, Weiju
The ASME construction code books specify materials and fabrication procedures that are acceptable for pressure technology applications. However, with few exceptions, the materials properties provided in the ASME code books provide no statistics or other information pertaining to material variability. Such information is central to the prediction and prevention of failure events. Many sources of materials data exist that provide variability information but such sources do not necessarily represent a consensus of experts with respect to the reported trends that are represented. Such a need has been identified by the ASME Standards Technology, LLC and initial steps have been takenmore » to address these needs: however, these steps are limited to project-specific applications only, such as the joint DOE-ASME project on materials for Generation IV nuclear reactors. In contrast to light-water reactor technology, the experience base for the Generation IV nuclear reactors is somewhat lacking and heavy reliance must be placed on model development and predictive capability. The database for model development is being assembled and includes existing code alloys such as alloy 800H and 9Cr-1Mo-V steel. Ownership and use rights are potential barriers that must be addressed.« less
Synthetic Vision Displays for Planetary and Lunar Lander Vehicles
NASA Technical Reports Server (NTRS)
Arthur, Jarvis J., III; Prinzel, Lawrence J., III; Williams, Steven P.; Shelton, Kevin J.; Kramer, Lynda J.; Bailey, Randall E.; Norman, Robert M.
2008-01-01
Aviation research has demonstrated that Synthetic Vision (SV) technology can substantially enhance situation awareness, reduce pilot workload, improve aviation safety, and promote flight path control precision. SV, and related flight deck technologies are currently being extended for application in planetary exploration vehicles. SV, in particular, holds significant potential for many planetary missions since the SV presentation provides a computer-generated view for the flight crew of the terrain and other significant environmental characteristics independent of the outside visibility conditions, window locations, or vehicle attributes. SV allows unconstrained control of the computer-generated scene lighting, terrain coloring, and virtual camera angles which may provide invaluable visual cues to pilots/astronauts, not available from other vision technologies. In addition, important vehicle state information may be conformally displayed on the view such as forward and down velocities, altitude, and fuel remaining to enhance trajectory control and vehicle system status. The paper accompanies a conference demonstration that introduced a prototype NASA Synthetic Vision system for lunar lander spacecraft. The paper will describe technical challenges and potential solutions to SV applications for the lunar landing mission, including the requirements for high-resolution lunar terrain maps, accurate positioning and orientation, and lunar cockpit display concepts to support projected mission challenges.
Diffraction spectral filter for use in extreme-UV lithography condenser
Sweatt, William C.; Tichenor, Daniel A.; Bernardez, Luis J.
2002-01-01
A condenser system for generating a beam of radiation includes a source of radiation light that generates a continuous spectrum of radiation light; a condenser comprising one or more first optical elements for collecting radiation from the source of radiation light and for generating a beam of radiation; and a diffractive spectral filter for separating first radiation light having a particular wavelength from the continuous spectrum of radiation light. Cooling devices can be employed to remove heat generated. The condenser system can be used with a ringfield camera in projection lithography.
NASA Astrophysics Data System (ADS)
Santhosh, C.; Dharmadhikari, A. K.; Alti, K.; Dharmadhikari, J. A.; Mathur, D.
2007-02-01
Propagation of ultrashort pulses of intense, infrared light through transparent medium gives rise to a visually spectacular phenomenon known as supercontinuum (white light) generation wherein the spectrum of transmitted light is very considerably broader than that of the incident light. We have studied the propagation of ultrafast (<45 fs) pulses of intense infrared light through biological media (water, and water doped with salivary proteins) which reveal that white light generation is severely suppressed in the presence of a major salivary protein, α-amylase.
The International Year of Light and Light-based Technologies
NASA Astrophysics Data System (ADS)
Pendrill, Ann-Marie
2015-05-01
I report on the opening ceremony of the International Year of Light and Light-based Technologies 2015 (IYL2015), which took place at the UNESCO headquarters in Paris, France, on 19-20 January 2015. Over the two days, more than 1000 participants from all over the world learned more about the fundamental properties of light and advanced photonics applications, the history of optics and its applications through the centuries, light poverty and light pollution, and light for everyday life, health and research.
Sonoluminescence: A Galaxy of Nanostars Created in a Beaker
NASA Technical Reports Server (NTRS)
Wrbanek, John D.; Fralick, Gustave C.; Wrbanek, Susan Y.; Weiland, Kenneth E.
2005-01-01
As part of basic and applied research on advanced instrumentation technologies, the NASA Glenn Research Center is examining applications for sonoluminescence: ultrasonically produced glowing bubbles that are hotter than the Sun. In the last decade, those outside of the ultrasonic community have become interested in understanding sonoluminescence and in using some of its more interesting properties. First discovered in the 1930s as a byproduct of early work on sonar, the phenomenon is defined as the generation of light energy from sound waves. This glow, which was originally thought to be a form of static electricity, was found to be generated in flashes of much less than a billionth of a second that result when microscopic bubbles of air collapse. The temperature generated in the collapsing bubbles is at least 4 times that of the surface of the Sun.
Generalized receptor law governs phototaxis in the phytoplankton Euglena gracilis
Giometto, Andrea; Altermatt, Florian; Maritan, Amos; Stocker, Roman; Rinaldo, Andrea
2015-01-01
Phototaxis, the process through which motile organisms direct their swimming toward or away from light, is implicated in key ecological phenomena (including algal blooms and diel vertical migration) that shape the distribution, diversity, and productivity of phytoplankton and thus energy transfer to higher trophic levels in aquatic ecosystems. Phototaxis also finds important applications in biofuel reactors and microbiopropellers and is argued to serve as a benchmark for the study of biological invasions in heterogeneous environments owing to the ease of generating stochastic light fields. Despite its ecological and technological relevance, an experimentally tested, general theoretical model of phototaxis seems unavailable to date. Here, we present accurate measurements of the behavior of the alga Euglena gracilis when exposed to controlled light fields. Analysis of E. gracilis’ phototactic accumulation dynamics over a broad range of light intensities proves that the classic Keller–Segel mathematical framework for taxis provides an accurate description of both positive and negative phototaxis only when phototactic sensitivity is modeled by a generalized “receptor law,” a specific nonlinear response function to light intensity that drives algae toward beneficial light conditions and away from harmful ones. The proposed phototactic model captures the temporal dynamics of both cells’ accumulation toward light sources and their dispersion upon light cessation. The model could thus be of use in integrating models of vertical phytoplankton migrations in marine and freshwater ecosystems, and in the design of bioreactors. PMID:25964338
Generalized receptor law governs phototaxis in the phytoplankton Euglena gracilis.
Giometto, Andrea; Altermatt, Florian; Maritan, Amos; Stocker, Roman; Rinaldo, Andrea
2015-06-02
Phototaxis, the process through which motile organisms direct their swimming toward or away from light, is implicated in key ecological phenomena (including algal blooms and diel vertical migration) that shape the distribution, diversity, and productivity of phytoplankton and thus energy transfer to higher trophic levels in aquatic ecosystems. Phototaxis also finds important applications in biofuel reactors and microbiopropellers and is argued to serve as a benchmark for the study of biological invasions in heterogeneous environments owing to the ease of generating stochastic light fields. Despite its ecological and technological relevance, an experimentally tested, general theoretical model of phototaxis seems unavailable to date. Here, we present accurate measurements of the behavior of the alga Euglena gracilis when exposed to controlled light fields. Analysis of E. gracilis' phototactic accumulation dynamics over a broad range of light intensities proves that the classic Keller-Segel mathematical framework for taxis provides an accurate description of both positive and negative phototaxis only when phototactic sensitivity is modeled by a generalized "receptor law," a specific nonlinear response function to light intensity that drives algae toward beneficial light conditions and away from harmful ones. The proposed phototactic model captures the temporal dynamics of both cells' accumulation toward light sources and their dispersion upon light cessation. The model could thus be of use in integrating models of vertical phytoplankton migrations in marine and freshwater ecosystems, and in the design of bioreactors.
Non-invasive activation of optogenetic actuators
NASA Astrophysics Data System (ADS)
Birkner, Elisabeth; Berglund, Ken; Klein, Marguerita E.; Augustine, George J.; Hochgeschwender, Ute
2014-03-01
The manipulation of genetically targeted neurons with light (optogenetics) continues to provide unprecedented avenues into studying the function of the mammalian brain. However, potential translation into the clinical arena faces a number of significant hurdles, foremost among them the need for insertion of optical fibers into the brain to deliver light to opsins expressed on neuronal membranes. In order to overcome these hardware-related problems, we have developed an alternative strategy for delivering light to opsins which does not involve fiber implants. Rather, the light is produced by a protein, luciferase, which oxidizes intravenously applied substrate, thereby emitting bioluminescence. In proof-ofprinciple studies employing a fusion protein of a light-generating luciferase to a light-sensing opsin (luminopsin), we showed that light emitted by Gaussia luciferase is indeed able to activate channelrhodopsin, allowing modulation of neuronal activity when expressed in cultured neurons. Here we assessed applicability of the concept in vivo in mice expressing luminopsins from viral vectors and from genetically engineered transgenes. The experiments demonstrate that intravenously applied substrate reaches neurons in the brain, causing the luciferase to produce bioluminescence which can be imaged in vivo, and that activation of channelrhodopsin by bioluminescence is sufficient to affect behavior. Further developments of such technology based on combining optogenetics with bioluminescence - i.e. combining lightsensing molecules with biologically produced light through luciferases - should bring optogenetics closer to clinical applications.
NASA-UVA Light Aerospace Alloy and Structures Technology Program (LA2ST)
NASA Technical Reports Server (NTRS)
Gangloff, Richard P.
1994-01-01
The NASA-UVA Light Aerospace Alloy and Structures Technology (LA2ST) Program was initiated in 1986 and continues with a high level of activity. Projects are being conducted by graduate students and faculty advisors in the Department of Materials Science and Engineering, as well as in the Department of Civil Engineering and Applied Mechanics, at the University of Virginia. This work is funded by the NASA-Langley Research Center under Grant NAG-1-745. Here, we report on progress achieved between January 1 and June 30, 1994. These results were presented at the Fifth Annual NASA LA2ST Grant Review Meeting held at the Langley Research Center in July of 1994. The objective of the LA2ST Program is to conduct interdisciplinary graduate student research on the performance of next generation, lightweight aerospace alloys, composites, and thermal gradient structures in collaboration with NASA-Langley researchers. Specific technical objectives are presented for each research project. We generally aim to produce relevant data and basic understanding of material mechanical response, environmental/corrosion behavior, and microstructure; new monolithic and composite alloys; advanced processing methods; new solid and fluid mechanics analyses; measurement and modeling advances; and a pool of educated graduate students for aerospace technologies.
Mena, Ismael F; Cotillas, Salvador; Díaz, Elena; Sáez, Cristina; Mohedano, Ángel F; Rodrigo, Manuel A
2017-12-06
In this work, sono- and photoelectrolysis of synthetic wastewaters polluted with the ionic liquids 1-Butyl-3-methylimidazolium acetate (BmimAc) and chloride (BmimCl) were investigated with diamond anodes. The results were compared to those attained by enhancing bare electrolysis with irradiation by UV light or with the application of high-frequency ultrasound (US). Despite its complex heterocyclic structure, the Bmim + cation was successfully depleted with the three technologies that were tested and was mainly transformed into four different organic intermediates, an inorganic nitrogen species and carbon dioxide. Regardless of the technology that was evaluated, removal of the heterocyclic ring is much less efficient (and much slower) than oxidation of the counter ion. In turn, the counter ion influences the rate of removal of the ionic liquid cation. Thus, the electrolysis and photoelectrolysis of BmimAc are much less efficient than sonoelectrolysis, but their differences become much less important in the case of BmimCl. In this later case, the most efficient technology is photoelectrolysis. This result is directly related to the generation of free radicals in the solution by irradiation of the electrochemical system with UV light, which contributes significantly to the removal of Bmim + . Copyright © 2017 Elsevier B.V. All rights reserved.
Altered Perspectives: Immersive Environments
NASA Astrophysics Data System (ADS)
Shipman, J. S.; Webley, P. W.
2016-12-01
Immersive environments provide an exciting experiential technology to visualize the natural world. Given the increasing accessibility of 360o cameras and virtual reality headsets we are now able to visualize artistic principles and scientific concepts in a fully immersive environment. The technology has become popular for photographers as well as designers, industry, educational groups, and museums. Here we show a sci-art perspective on the use of optics and light in the capture and manipulation of 360o images and video of geologic phenomena and cultural heritage sites in Alaska, England, and France. Additionally, we will generate intentionally altered perspectives to lend a surrealistic quality to the landscapes. Locations include the Catacombs of Paris, the Palace of Versailles, and the Northern Lights over Fairbanks, Alaska. Some 360o view cameras now use small portable dual lens technology extending beyond the 180o fish eye lens previously used, providing better coverage and image quality. Virtual reality headsets range in level of sophistication and cost, with the most affordable versions using smart phones and Google Cardboard viewers. The equipment used in this presentation includes a Ricoh Theta S spherical imaging camera. Here we will demonstrate the use of 360o imaging with attendees being able to be part of the immersive environment and experience our locations as if they were visiting themselves.
Structured light optical microscopy for three-dimensional reconstruction of technical surfaces
NASA Astrophysics Data System (ADS)
Kettel, Johannes; Reinecke, Holger; Müller, Claas
2016-04-01
In microsystems technology quality control of micro structured surfaces with different surface properties is playing an ever more important role. The process of quality control incorporates three-dimensional (3D) reconstruction of specularand diffusive reflecting technical surfaces. Due to the demand on high measurement accuracy and data acquisition rates, structured light optical microscopy has become a valuable solution to solve this problem providing high vertical and lateral resolution. However, 3D reconstruction of specular reflecting technical surfaces still remains a challenge to optical measurement principles. In this paper we present a measurement principle based on structured light optical microscopy which enables 3D reconstruction of specular- and diffusive reflecting technical surfaces. It is realized using two light paths of a stereo microscope equipped with different magnification levels. The right optical path of the stereo microscope is used to project structured light onto the object surface. The left optical path is used to capture the structured illuminated object surface with a camera. Structured light patterns are generated by a Digital Light Processing (DLP) device in combination with a high power Light Emitting Diode (LED). Structured light patterns are realized as a matrix of discrete light spots to illuminate defined areas on the object surface. The introduced measurement principle is based on multiple and parallel processed point measurements. Analysis of the measured Point Spread Function (PSF) by pattern recognition and model fitting algorithms enables the precise calculation of 3D coordinates. Using exemplary technical surfaces we demonstrate the successful application of our measurement principle.
3. Credit PEM. Interior of Martinsburg plant showing two MacIntousch ...
3. Credit PEM. Interior of Martinsburg plant showing two MacIntousch Seymore steam engines and one Taylor steam engine belt driving (from let to right) a sperry 30 light, 220 Volt generator, a Westinghouse 900 light, 2200 Volt generator, a Ball 80 light are generator, and two Edison, 900 light, 220 Volt generators. Note switchboard to left. Photo c. 1896. - Dam No. 4 Hydroelectric Plant, Potomac River, Martinsburg, Berkeley County, WV
NASA Astrophysics Data System (ADS)
Li, Qingli; Liu, Hongying; Wang, Yiting; Sun, Zhen; Guo, Fangmin; Zhu, Jianzhong
2014-12-01
Histological observation of dual-stained colon sections is usually performed by visual observation under a light microscope, or by viewing on a computer screen with the assistance of image processing software in both research and clinical settings. These traditional methods are usually not sufficient to reliably differentiate spatially overlapping chromogens generated by different dyes. Hyperspectral microscopic imaging technology offers a solution for these constraints as the hyperspectral microscopic images contain information that allows differentiation between spatially co-located chromogens with similar but different spectra. In this paper, a hyperspectral microscopic imaging (HMI) system is used to identify methyl green and nitrotetrazolium blue chloride in dual-stained colon sections. Hyperspectral microscopic images are captured and the normalized score algorithm is proposed to identify the stains and generate the co-expression results. Experimental results show that the proposed normalized score algorithm can generate more accurate co-localization results than the spectral angle mapper algorithm. The hyperspectral microscopic imaging technology can enhance the visualization of dual-stained colon sections, improve the contrast and legibility of each stain using their spectral signatures, which is helpful for pathologist performing histological analyses.
Estimating global per-capita carbon emissions with VIIRS nighttime lights satellite data
NASA Astrophysics Data System (ADS)
Jasmin, T.; Desai, A. R.; Pierce, R. B.
2015-12-01
With the launch of the Suomi National Polar-orbiting Partnership (NPP) satellite in November 2011, we now have nighttime lights remote sensing capability vastly improved over the predecessor Defense Meteorological Satellite Program (DMSP), owing to improved spatial and radiometric resolution provided by the Visible Infrared Imaging Radiometer Suite (VIIRS) Day Night Band (DNB) along with technology improvements in data transfer, processing, and storage. This development opens doors for improving novel scientific applications utilizing remotely sensed low-level visible light, for purposes ranging from estimating population to inferring factors relating to economic development. For example, the success of future international agreements to reduce greenhouse gas emissions will be dependent on mechanisms to monitor remotely for compliance. Here, we discuss implementation and evaluation of the VRCE system (VIIRS Remote Carbon Estimates), developed at the University of Wisconsin-Madison, which provides monthly independent, unbiased estimates of per-capita carbon emissions. Cloud-free global composites of Earth nocturnal lighting are generated from VIIRS DNB at full spatial resolution (750 meter). A population equation is derived from a linear regression of DNB radiance sums at state level to U.S. Census data. CO2 emissions are derived from a linear regression of VIIRS DNB radiance sums to U.S. Department of Energy emission estimates. Regional coefficients for factors such as percentage of energy use from renewable sources are factored in, and together these equations are used to generate per-capita CO2 emission estimates at the country level.
Gharaibeh, Almutez M.; Villanueva, Asier; Mas, David; Espinosa, Julian
2018-01-01
Purpose To assess anterior corneal surface stability 12 months following hyperopic LASIK correction with a light propagation algorithm. Setting Vissum Instituto Oftalmológico de Alicante, Universidad Miguel Hernández, Alicante, Spain. Methods This retrospective consecutive observational study includes 37 eyes of 37 patients treated with 6th-generation excimer laser platform (Schwind Amaris). Hyperopic LASIK was performed in all of them by the same surgeon (JLA) and completed 12-month follow-up. Corneal topography was analyzed with a light propagation algorithm, to assess the stability of the corneal outcomes along one year of follow-up. Results Between three and twelve months postoperatively, an objective corneal power (OCP) regression of 0.39 D and 0.41 D was found for 6 mm and 9 mm central corneal zone, respectively. Subjective outcomes at the end of the follow-up period were as follows: 65% of eyes had spherical equivalent within ±0.50 D. 70% of eyes had an uncorrected distance visual acuity 20/20 or better. 86% of eyes had the same or better corrected distance visual acuity. In terms of stability, 0.14 D of regression was found. No statistically significant differences were found for all the study parameters evaluated at different postoperative moments over the 12-month period. Conclusions Light propagation analysis confirms corneal surface stability following modern hyperopic LASIK with a 6th-generation excimer laser technology over a 12-month period. PMID:29785300
DOE Office of Scientific and Technical Information (OSTI.GOV)
Henry, C.P.; Marsh, E.J.
1997-06-01
In 1990, the Governor of New York State issued Executive Order No. 132, directing all state agencies to reduce energy consumption by 20% from the base year of 1988/89 by the year 2000. To assist in meeting this goal, the New York State Office of Mental Health (OMH) established the Lighting Revitalization Program in 1992. State facilities are divided into five regions, each served by existing Environmental Revitalization Teams. OMH supplemented these teams with lighting technicians in this new program. The program`s goal was to rehabilitate outdated, inefficient lighting systems throughout 28 OMH facilities, totaling 28 million square feet inmore » area. OMH requested the former Facility Development Corporation (FDC), now the Dormitory Authority of the State of New York (DASNY), to contract with Novus Engineering to evaluate the relative efficiency of T8 and T12 ballasts. Novus contracted an independent laboratory, Eastern Testing Laboratories (ETL), for performance testing. ETL tested four ballast/lamp configurations for light Output and input power, and Novus analyzed the results for relative efficiency and also calculated 25-year life cycle costs. The test results indicated that the efficiencies of the T12/34W and T8/32W ballast/lamp technologies were nearly identical. The input power and light output of these systems were similar. The lumens per Watt ratings for the two systems were nearly equal, with the T8 technology being only about two percent more efficient, generating more light with similar input power. The life cycle costs for the two systems were nearly identical, with the T12 system providing a slightly lower life cycle cost. Given the above considerations, the agency has been installing T12 electronic ballasts and 34W lamps in buildings where fluorescent fixtures warranted upgrading. This type of retrofit goes against current trends, but the use of T8 system could not be justified in buildings undergoing minor retrofitting.« less
Apparatus, system, and method for laser-induced breakdown spectroscopy
Effenberger, Jr., Andrew J; Scott, Jill R; McJunkin, Timothy R
2014-11-18
In laser-induced breakdown spectroscopy (LIBS), an apparatus includes a pulsed laser configured to generate a pulsed laser signal toward a sample, a constructive interference object and an optical element, each located in a path of light from the sample. The constructive interference object is configured to generate constructive interference patterns of the light. The optical element is configured to disperse the light. A LIBS system includes a first and a second optical element, and a data acquisition module. The data acquisition module is configured to determine an isotope measurement based, at least in part, on light received by an image sensor from the first and second optical elements. A method for performing LIBS includes generating a pulsed laser on a sample to generate light from a plasma, generating constructive interference patterns of the light, and dispersing the light into a plurality of wavelengths.
A Feasibility Study on Generation of Acoustic Waves Utilizing Evanescent Light
NASA Astrophysics Data System (ADS)
Matsuya, I.; Matozaki, K.; Kosugi, A.; Ihara, I.
2014-06-01
A new approach of generating acoustic waves utilizing evanescent light is presented. The evanescent light is a non-propagating electromagnetic wave that exhibits exponential decay with distance from the surface at which the total internal reflection of light is formed. In this research, the evanescent light during total internal reflection at prism surface is utilized for generating acoustic waves in aluminium and the feasibility for ultrasonic measurements is discussed. Pulsed Nd:YAG laser with 0.36 J/cm2 power density is used and the incident angle during the total internal reflection is arranged to be 69.0° for generating the evanescent light. It has been demonstrated that the amplitude of the acoustic waves by means of evanescent light is about 1/14 as large as the one generated by the conventional pulsed laser. This reveals the possibility of using a laser ultrasonic technique with near-field optics.
Femtosecond timing distribution and control for next generation accelerators and light sources
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, Li -Jin
Femtosecond Timing Distribution At LCLS Free-electron-lasers (FEL) have the capability of producing high photon flux from the IR to the hard x-ray wavelength range and to emit femtosecond and eventually even attosecond pulses. This makes them an ideal tool for fundamental as well as applied re-search. Timing precision at the Stanford Linear Coherent Light Source (LCLS) between the x-ray FEL (XFEL) and ultrafast optical lasers is currently no better than 100 fs RMS. Ideally this precision should be much better and could be limited only by the x-ray pulse duration, which can be as short as a few femtoseconds. Anmore » increasing variety of science problems involving electron and nuclear dynamics in chemical and material systems will become accessible as the timing improves to a few femtoseconds. Advanced methods of electron beam conditioning or pulse injection could allow the FEL to achieve pulse durations less than one femtosecond. The objective of the work described in this proposal is to set up an optical timing distribution system based on mode locked Erbium doped fiber lasers at LCLS facility to improve the timing precision in the facility and allow time stamping with a 10 fs precision. The primary commercial applications for optical timing distributions systems are seen in the worldwide accelerator facilities and next generation light sources community. It is reasonable to expect that at least three major XFELs will be built in the next decade. In addition there will be up to 10 smaller machines, such as FERMI in Italy and Maxlab in Sweden, plus the market for upgrading already existing facilities like Jefferson Lab. The total market is estimated to be on the order of a 100 Million US Dollars. The company owns the exclusive rights to the IP covering the technology enabling sub-10 fs synchronization systems. Testing this technology, which has set records in a lab environment, at LCLS, hence in a real world scenario, is an important corner stone of bringing the technology to market.« less
Integrated photocatalytic filtration array for indoor air quality control.
Denny, Frans; Permana, Eric; Scott, Jason; Wang, Jing; Pui, David Y H; Amal, Rose
2010-07-15
Photocatalytic and filtration technologies were integrated to develop a hybrid system capable of removing and oxidizing organic pollutants from an air stream. A fluidized bed aerosol generator (FBAG) was adapted to prepare TiO(2)-loaded ventilation filters for the photodegradation of gas phase ethanol. Compared to a manually loaded filter, the ethanol photodegradation rate constant for the FBAG coated filter increased by 361%. Additionally, the presence of the photogenerated intermediate product, acetaldehyde, was reduced and the time for mineralization to CO(2) was accelerated. These improvements were attributed to the FBAG system providing a more uniform distribution of TiO(2) particles across the filter surface leading to greater accessibility by the UV light. A dual-UV-lamp system, as opposed to a single-lamp system, enhanced photocatalytic filter performance demonstrating the importance of high light irradiance and light distribution across the filter surface. Substituting the blacklight blue lamps with a UV-light-emitting-diode (UV-LED) array led to further improvement as well as suppressed the electrical energy per order (EE/O) by a factor of 6. These improvements derived from the more uniform distribution of light irradiance as well as the higher efficiency of UV-LEDs in converting electrical energy to photons.
Wang, Zhibin; Cheng, Tai; Wang, Fuzhi; Bai, Yiming; Bian, Xingming; Zhang, Bing; Hayat, Tasawar; Alsaedi, Ahmed; Tan, Zhan'ao
2018-05-31
Stable and efficient red (R), green (G), and blue (B) light sources based on solution-processed quantum dots (QDs) play important roles in next-generation displays and solid-state lighting technologies. The brightness and efficiency of blue QDs-based light-emitting diodes (LEDs) remain inferior to their red and green counterparts, due to the inherently unfavorable energy levels of different colors of light. To solve these problems, a device structure should be designed to balance the injection holes and electrons into the emissive QD layer. Herein, through a simple autoxidation strategy, pure blue QD-LEDs which are highly bright and efficient are demonstrated, with a structure of ITO/PEDOT:PSS/Poly-TPD/QDs/Al:Al2O3. The autoxidized Al:Al2O3 cathode can effectively balance the injected charges and enhance radiative recombination without introducing an additional electron transport layer (ETL). As a result, high color-saturated blue QD-LEDs are achieved with a maximum luminance over 13,000 cd m -2 , and a maximum current efficiency of 1.15 cd A -1 . The easily controlled autoxidation procedure paves the way for achieving high-performance blue QD-LEDs.
Simultaneous entanglement swapping of multiple orbital angular momentum states of light.
Zhang, Yingwen; Agnew, Megan; Roger, Thomas; Roux, Filippus S; Konrad, Thomas; Faccio, Daniele; Leach, Jonathan; Forbes, Andrew
2017-09-21
High-bit-rate long-distance quantum communication is a proposed technology for future communication networks and relies on high-dimensional quantum entanglement as a core resource. While it is known that spatial modes of light provide an avenue for high-dimensional entanglement, the ability to transport such quantum states robustly over long distances remains challenging. To overcome this, entanglement swapping may be used to generate remote quantum correlations between particles that have not interacted; this is the core ingredient of a quantum repeater, akin to repeaters in optical fibre networks. Here we demonstrate entanglement swapping of multiple orbital angular momentum states of light. Our approach does not distinguish between different anti-symmetric states, and thus entanglement swapping occurs for several thousand pairs of spatial light modes simultaneously. This work represents the first step towards a quantum network for high-dimensional entangled states and provides a test bed for fundamental tests of quantum science.Entanglement swapping in high dimensions requires large numbers of entangled photons and consequently suffers from low photon flux. Here the authors demonstrate entanglement swapping of multiple spatial modes of light simultaneously, without the need for increasing the photon numbers with dimension.
NASA Astrophysics Data System (ADS)
Ye, Linchao; Belloni, Paola; Möller, Knut
2011-10-01
Within the framework of a project conducted together with an industrial partner, a self-disinfecting operation interface with a glass panel is being developed. The concept of self-disinfection is based on the exploitation of the photocatalytical effect induced by a TiO2-coating on the glass surface under UV(A) light, which would make the touch screen antimicrobial. High-power UV-LEDs instead of conventional UV-lamps have been employed as light source. The main goal and challenge of the optical design is to generate an efficient and preferably homogeneous UV field on the TiO2-coated side while keeping the UV-LEDs concealed, i.e. invisible to the user. Therefore common backlighting systems have been used as reference and modified to meet the concrete requirements. Primary analysis and optical simulations have been performed with the software LightTools®. Several patterns for light redirection (i.e. 3D-spherical texture, 3D-rectangular texture and 2D-circular serigraph) have been investigated, compared and evaluated. Finally the pattern design which both fulfills all the predefined boundary conditions and simultaneously reduces the costs has been chosen.
NASA Astrophysics Data System (ADS)
Tsai, Chun-Wei; Wang, Chen; Lyu, Bo-Han; Chu, Chen-Hsien
2017-08-01
Digital Electro-optics Platform is the main concept of Jasper Display Corp. (JDC) to develop various applications. These applications are based on our X-on-Silicon technologies, for example, X-on-Silicon technologies could be used on Liquid Crystal on Silicon (LCoS), Micro Light-Emitting Diode on Silicon (μLEDoS), Organic Light-Emitting Diode on Silicon (OLEDoS), and Cell on Silicon (CELLoS), etc. LCoS technology is applied to Spatial Light Modulator (SLM), Dynamic Optics, Wavelength Selective Switch (WSS), Holographic Display, Microscopy, Bio-tech, 3D Printing and Adaptive Optics, etc. In addition, μLEDoS technology is applied to Augmented Reality (AR), Head Up Display (HUD), Head-mounted Display (HMD), and Wearable Devices. Liquid Crystal on Silicon - Spatial Light Modulator (LCoSSLM) based on JDC's On-Silicon technology for both amplitude and phase modulation, have an expanding role in several optical areas where light control on a pixel-by-pixel basis is critical for optimum system performance. Combination of the advantage of hardware and software, we can establish a "dynamic optics" for the above applications or more. Moreover, through the software operation, we can control the light more flexible and easily as programmable light processor.
Complete solid state lighting (SSL) line at CEA LETI
NASA Astrophysics Data System (ADS)
Robin, I. C.; Ferret, P.; Dussaigne, A.; Bougerol, C.; Salomon, D.; Chen, X. J.; Charles, M.; Tchoulfian, P.; Gasse, A.; Lagrange, A.; Consonni, M.; Bono, H.; Levy, F.; Desieres, Y.; Aitmani, A.; Makram-Matta, S.; Bialic, E.; Gorrochategui, P.; Mendizabal, L.
2014-09-01
With a long experience in optoelectronics, CEA-LETI has focused on Light Emitting Diode (LED) lighting since 2006. Today, all the technical challenges in the implementation of GaN LED based solid state lighting (SSL) are addressed at CEA-LETI who is now an RandD player throughout the entire value chain of LED lighting. The SSL Line at CEA-LETI first deals with the simulation of the active structures and LED devices. Then the growth is addressed in particular 2D growth on 200 mm silicon substrates. Then, technological steps are developed for the fabrication of LED dies with innovative architectures. For instance, Versatile LED Array Devices are currently being developed with a dedicated μLED technology. The objective in this case is to achieve monolithical LED arrays reported and interconnected through a silicon submount. In addition to the required bonding and 3D integration technologies, new solutions for LED chip packaging, thermal management of LED lamps and luminaires are also addressed. LETI is also active in Smart Lighting concepts which offer the possibility of new application fields for SSL technologies. An example is the recent development at CEA LETI of Visible Light Communication Technology also called LiFi. With this technology, we demonstrated a transmission rate up to 10 Mb/s and real time HD-Video transmission.
Manipulation of long-term dynamics in a colloidal active matter system using speckle light fields
NASA Astrophysics Data System (ADS)
Pince, Ercag; Velu, Sabareesh K. P.; Callegari, Agnese; Elahi, Parviz; Gigan, Sylvain; Volpe, Giovanni; Volpe, Giorgio
Particles undergoing a stochastic motion within a disordered medium is a ubiquitous physical and biological phenomena. Examples can be given from organelles performing tasks in the cytoplasm to large animals moving in patchy environment. Here, we use speckle light fields to study the anomalous diffusion in an active matter system consisting of micron-sized silica particles(diameter 5 μm) and motile bacterial cells (E. coli). The speckle light fields are generated by mode mixing inside a multimode optical fiber where a small amount of incident laser power is needed to obtain an effective disordered optical landscape for the purpose of optical manipulation. We experimentally show how complex potentials contribute to the long-term dynamics of the active matter system and observed an enhanced diffusion of particles interacting with the active bacterial bath in the speckle light fields. We showed that this effect can be tuned and controlled by varying the intensity and the statistical properties of the speckle pattern. Potentially, these results could be of interest for many technological applications, such as the manipulation of microparticles inside optically disordered media of biological interest.
High definition surface micromachining of LiNbO 3 by ion implantation
NASA Astrophysics Data System (ADS)
Chiarini, M.; Bentini, G. G.; Bianconi, M.; De Nicola, P.
2010-10-01
High Energy Ion Implantation (HEII) of both medium and light mass ions has been successfully applied for the surface micromachining of single crystal LiNbO 3 (LN) substrates. It has been demonstrated that the ion implantation process generates high differential etch rates in the LN implanted areas, when suitable implantation parameters, such as ion species, fluence and energy, are chosen. In particular, when traditional LN etching solutions are applied to suitably ion implanted regions, etch rates values up to three orders of magnitude higher than the typical etching rates of the virgin material, are registered. Further, the enhancement in the etching rate has been observed on x, y and z-cut single crystalline material, and, due to the physical nature of the implantation process, it is expected that it can be equivalently applied also to substrates with different crystallographic orientations. This technique, associated with standard photolithographic technologies, allows to generate in a fast and accurate way very high aspect ratio relief micrometric structures on LN single crystal surface. In this work a description of the developed technology is reported together with some examples of produced micromachined structures: in particular very precisely defined self sustaining suspended structures, such as beams and membranes, generated on LN substrates, are presented. The developed technology opens the way to actual three dimensional micromachining of LN single crystals substrates and, due to the peculiar properties characterising this material, (pyroelectric, electro-optic, acousto-optic, etc.), it allows the design and the production of complex integrated elements, characterised by micrometric features and suitable for the generation of advanced Micro Electro Optical Systems (MEOS).
The Use of AlphaScreen Technology in HTS: Current Status
Eglen, Richard M; Reisine, Terry; Roby, Philippe; Rouleau, Nathalie; Illy, Chantal; Bossé, Roger; Bielefeld, Martina
2008-01-01
AlphaScreen (Amplified Luminescent Proximity Homogeneous Assay Screen) is versatile assay technology developed to measuring analytes using a homogenous protocol. This technology is an example of a bead-based proximity assay and was developed from a diagnostic assay technology known as LOCI (Luminescent Oxygen Channeling Assay). Here, singlet oxygen molecules, generated by high energy irradiation of Donor beads, travel over a constrained distance (approx. 200 nm) to Acceptor beads. This results in excitation of a cascading series of chemical reactions, ultimately causing generation of a chemiluminescent signal. In the past decade, a wide variety of applications has been reported, ranging from detection of analytes involved in cell signaling, including protein:protein, protein:peptide, protein:small molecule or peptide:peptide interactions. Numerous homogeneous HTS-optimized assays have been reported using the approach, including generation of second messengers (such as accumulation of cyclic AMP, cyclic GMP, inositol [1, 4, 5] trisphosphate or phosphorylated ERK) from liganded GPCRs or tyrosine kinase receptors, post-translational modification of proteins (such as proteolytic cleavage, phosphorylation, ubiquination and sumoylation) as well as protein-protein and protein-nucleic acid interactions. Recently, the basic AlphaScreen technology was extended in that the chemistry of the Acceptor bead was modified such that emitted light is more intense and spectrally defined, thereby markedly reducing interference from biological fluid matrices (such as trace hemolysis in serum and plasma). In this format, referred to as AlphaLISA, it provides an alternative technology to classical ELISA assays and is suitable for high throughput automated fluid dispensing and detection systems. Collectively, AlphaScreen and AlphaLISA technologies provide a facile assay platform with which one can quantitate complex cellular processes using simple no-wash microtiter plate based assays. They provide the means by which large compound libraries can be screened in a high throughput fashion at a diverse range of therapeutically important targets, often not readily undertaken using other homogeneous assay technologies. This review assesses the current status of the technology in drug discovery, in general, and high throughput screening (HTS), in particular. PMID:20161822
A GPU-based mipmapping method for water surface visualization
NASA Astrophysics Data System (ADS)
Li, Hua; Quan, Wei; Xu, Chao; Wu, Yan
2018-03-01
Visualization of water surface is a hot topic in computer graphics. In this paper, we presented a fast method to generate wide range of water surface with good image quality both near and far from the viewpoint. This method utilized uniform mesh and Fractal Perlin noise to model water surface. Mipmapping technology was enforced to the surface textures, which adjust the resolution with respect to the distance from the viewpoint and reduce the computing cost. Lighting effect was computed based on shadow mapping technology, Snell's law and Fresnel term. The render pipeline utilizes a CPU-GPU shared memory structure, which improves the rendering efficiency. Experiment results show that our approach visualizes water surface with good image quality at real-time frame rates performance.
The cryogenic dark matter search low ionization-threshold experiment
NASA Astrophysics Data System (ADS)
Basu Thakur, Ritoban
Over 80 years ago we discovered the presence of Dark Matter in our universe. Endeavors in astronomy and cosmology are in consensus with ever improving precision that Dark Matter constitutes an essential 27% of our universe. The Standard Model of Particle Physics does not provide any answers to the Dark Matter problem. It is imperative that we understand Dark Matter and discover its fundamental nature. This is because, alongside other important factors, Dark Matter is responsible for formation of structure in our universe. The very construct in which we sit is defined by its abundance. The Milky Way galaxy, hence life, wouldn't have formed if small over densities of Dark Matter had not caused sufficient accretion of stellar material. Marvelous experiments have been designed based on basic notions to directly and indirectly study Dark Matter, and the Cryogenic Dark Matter Search (CDMS) experiment has been a pioneer and forerunner in the direct detection field. Generations of the CDMS experiment were designed with advanced scientific upgrades to detect Dark Matter particles of mass O(100) GeV/c2. This mass-scale was set primarily by predictions from Super Symmetry. Around 2013 the canonical SUSY predictions were losing some ground and several observations (rather hints of signals) from various experiments indicated to the possibility of lighter Dark Matter of mass O(10) GeV/c2. While the SuperCDMS experiment was probing the regular parameter space, the CDMSlite experiment was conceived to dedicatedly search for light Dark Matter using a novel technology. "CDMSlite" stands for CDMS - low ionization threshold experiment. Here we utilize a unique electron phonon coupling mechanism to measure ionization generated by scattering of light particles. Typically signals from such low energy recoils would be washed under instrumental noise.In CDMSlite via generation of Luke-Neganov phonons we can detect the small ionization energies, amplified in phonon modes during charge transport. This technology allows us to reach very low thresholds and reliably measure and investigate low energy recoils from light Dark Matter particles. This thesis describes the physics behind CDMSlite, the experimenta design and the first science results from CDMSlite operated at the Soudan Underground Laboratory.
The Cryogenic Dark Matter Search low ionization-threshold experiment
DOE Office of Scientific and Technical Information (OSTI.GOV)
Basu Thakur, Ritoban
2014-01-01
Over 80 years ago we discovered the presence of Dark Matter in our universe. Endeavors in astronomy and cosmology are in consensus with ever improving precision that Dark Matter constitutes an essential 27% of our universe. The Standard Model of Particle Physics does not provide any answers to the Dark Matter problem. It is imperative that we understand Dark Matter and discover its fundamental nature. This is because, alongside other important factors, Dark Matter is responsible for formation of structure in our universe. The very construct in which we sit is defined by its abundance. The Milky Way galaxy, hencemore » life, wouldn't have formed if small over densities of Dark Matter had not caused sufficient accretion of stellar material. Marvelous experiments have been designed based on basic notions to directly and in-directly study Dark Matter, and the Cryogenic Dark Matter Search (CDMS) experiment has been a pioneer and forerunner in the direct detection field. Generations of the CDMS experiment were designed with advanced scientific upgrades to detect Dark Matter particles of mass O(100) GeV/c 2. This mass-scale was set primarily by predictions from Super Symmetry. Around 2013 the canonical SUSY predictions were losing some ground and several observations (rather hints of signals) from various experiments indicated to the possibility of lighter Dark Matter of mass O(10) GeV/c 2. While the SuperCDMS experiment was probing the regular parameter space, the CDMSlite experiment was conceived to dedicatedly search for light Dark Matter using a novel technology. "CDMSlite" stands for CDMS - low ionization threshold experiment. Here we utilize a unique electron phonon coupling mechanism to measure ionization generated by scattering of light particles. Typically signals from such low energy recoils would be washed under instrumental noise. In CDMSlite via generation of Luke-Neganov phonons we can detect the small ionization energies, amplified in phonon modes during charge transport. This technology allows us to reach very low thresholds and reliably measure and investigate low energy recoils from light Dark Matter particles. This thesis describes the physics behind CDMSlite, the experimental design and the first science results from CDMSlite operated at the Soudan Underground Laboratory.« less
Particle measurement systems and methods
Steele, Paul T [Livermore, CA
2011-10-04
A system according to one embodiment includes a light source for generating light fringes; a sampling mechanism for directing a particle through the light fringes; and at least one light detector for detecting light scattered by the particle as the particle passes through the light fringes. A method according to one embodiment includes generating light fringes using a light source; directing a particle through the light fringes; and detecting light scattered by the particle as the particle passes through the light fringes using at least one light detector.
Namikawa, Tsutomu; Fujisawa, Kazune; Munekage, Eri; Iwabu, Jun; Uemura, Sunao; Tsujii, Shigehiro; Maeda, Hiromichi; Kitagawa, Hiroyuki; Fukuhara, Hideo; Inoue, Keiji; Sato, Takayuki; Kobayashi, Michiya; Hanazaki, Kazuhiro
2018-04-04
The natural amino acid 5-aminolevulinic acid (ALA) is a protoporphyrin IX (PpIX) precursor and a new-generation photosensitive substance that accumulates specifically in cancer cells. When indocyanine green (ICG) is irradiated with near-infrared (NIR) light, it shifts to a higher energy state and emits infrared light with a longer wavelength than the irradiated NIR light. Photodynamic diagnosis (PDD) using ALA and ICG-based NIR fluorescence imaging has emerged as a new diagnostic technique. Specifically, in laparoscopic examinations for serosa-invading advanced gastric cancer, peritoneal metastases could be detected by ALA-PDD, but not by conventional visible-light imaging. The HyperEye Medical System (HEMS) can visualize ICG fluorescence as color images simultaneously projected with visible light in real time. This ICG fluorescence method is widely applicable, including for intraoperative identification of sentinel lymph nodes, visualization of blood vessels in organ resection, and blood flow evaluation during surgery. Fluorescence navigation by ALA-PDD and NIR using ICG imaging provides good visualization and detection of the target lesions that is not possible with the naked eye. We propose that this technique should be used in fundamental research on the relationship among cellular dynamics, metabolic enzymes, and tumor tissues, and to evaluate clinical efficacy and safety in multicenter cooperative clinical trials.
Color speckle in laser displays
NASA Astrophysics Data System (ADS)
Kuroda, Kazuo
2015-07-01
At the beginning of this century, lighting technology has been shifted from discharge lamps, fluorescent lamps and electric bulbs to solid-state lighting. Current solid-state lighting is based on the light emitting diodes (LED) technology, but the laser lighting technology is developing rapidly, such as, laser cinema projectors, laser TVs, laser head-up displays, laser head mounted displays, and laser headlamps for motor vehicles. One of the main issues of laser displays is the reduction of speckle noise1). For the monochromatic laser light, speckle is random interference pattern on the image plane (retina for human observer). For laser displays, RGB (red-green-blue) lasers form speckle patterns independently, which results in random distribution of chromaticity, called color speckle2).
Corrugated Textile based Triboelectric Generator for Wearable Energy Harvesting
Choi, A Young; Lee, Chang Jun; Park, Jiwon; Kim, Dogyun; Kim, Youn Tae
2017-01-01
Triboelectric energy harvesting has been applied to various fields, from large-scale power generation to small electronics. Triboelectric energy is generated when certain materials come into frictional contact, e.g., static electricity from rubbing a shoe on a carpet. In particular, textile-based triboelectric energy-harvesting technologies are one of the most promising approaches because they are not only flexible, light, and comfortable but also wearable. Most previous textile-based triboelectric generators (TEGs) generate energy by vertically pressing and rubbing something. However, we propose a corrugated textile-based triboelectric generator (CT-TEG) that can generate energy by stretching. Moreover, the CT-TEG is sewn into a corrugated structure that contains an effective air gap without additional spacers. The resulting CT-TEG can generate considerable energy from various deformations, not only by pressing and rubbing but also by stretching. The maximum output performances of the CT-TEG can reach up to 28.13 V and 2.71 μA with stretching and releasing motions. Additionally, we demonstrate the generation of sufficient energy from various activities of a human body to power about 54 LEDs. These results demonstrate the potential application of CT-TEGs for self-powered systems. PMID:28349928
Corrugated Textile based Triboelectric Generator for Wearable Energy Harvesting
NASA Astrophysics Data System (ADS)
Choi, A. Young; Lee, Chang Jun; Park, Jiwon; Kim, Dogyun; Kim, Youn Tae
2017-03-01
Triboelectric energy harvesting has been applied to various fields, from large-scale power generation to small electronics. Triboelectric energy is generated when certain materials come into frictional contact, e.g., static electricity from rubbing a shoe on a carpet. In particular, textile-based triboelectric energy-harvesting technologies are one of the most promising approaches because they are not only flexible, light, and comfortable but also wearable. Most previous textile-based triboelectric generators (TEGs) generate energy by vertically pressing and rubbing something. However, we propose a corrugated textile-based triboelectric generator (CT-TEG) that can generate energy by stretching. Moreover, the CT-TEG is sewn into a corrugated structure that contains an effective air gap without additional spacers. The resulting CT-TEG can generate considerable energy from various deformations, not only by pressing and rubbing but also by stretching. The maximum output performances of the CT-TEG can reach up to 28.13 V and 2.71 μA with stretching and releasing motions. Additionally, we demonstrate the generation of sufficient energy from various activities of a human body to power about 54 LEDs. These results demonstrate the potential application of CT-TEGs for self-powered systems.
Ju, Sanghyun; Li, Jianfeng; Liu, Jun; Chen, Po-Chiang; Ha, Young-Geun; Ishikawa, Fumiaki; Chang, Hsiaokang; Zhou, Chongwu; Facchetti, Antonio; Janes, David B; Marks, Tobin J
2008-04-01
Optically transparent, mechanically flexible displays are attractive for next-generation visual technologies and portable electronics. In principle, organic light-emitting diodes (OLEDs) satisfy key requirements for this application-transparency, lightweight, flexibility, and low-temperature fabrication. However, to realize transparent, flexible active-matrix OLED (AMOLED) displays requires suitable thin-film transistor (TFT) drive electronics. Nanowire transistors (NWTs) are ideal candidates for this role due to their outstanding electrical characteristics, potential for compact size, fast switching, low-temperature fabrication, and transparency. Here we report the first demonstration of AMOLED displays driven exclusively by NW electronics and show that such displays can be optically transparent. The displays use pixel dimensions suitable for hand-held applications, exhibit 300 cd/m2 brightness, and are fabricated at temperatures suitable for integration on plastic substrates.
Small Molecule Organic Optoelectronic Devices
NASA Astrophysics Data System (ADS)
Bakken, Nathan
Organic optoelectronics include a class of devices synthesized from carbon containing 'small molecule' thin films without long range order crystalline or polymer structure. Novel properties such as low modulus and flexibility as well as excellent device performance such as photon emission approaching 100% internal quantum efficiency have accelerated research in this area substantially. While optoelectronic organic light emitting devices have already realized commercial application, challenges to obtain extended lifetime for the high energy visible spectrum and the ability to reproduce natural white light with a simple architecture have limited the value of this technology for some display and lighting applications. In this research, novel materials discovered from a systematic analysis of empirical device data are shown to produce high quality white light through combination of monomer and excimer emission from a single molecule: platinum(II) bis(methyl-imidazolyl)toluene chloride (Pt-17). Illumination quality achieved Commission Internationale de L'Eclairage (CIE) chromaticity coordinates (x = 0.31, y = 0.38) and color rendering index (CRI) > 75. Further optimization of a device containing Pt-17 resulted in a maximum forward viewing power efficiency of 37.8 lm/W on a plain glass substrate. In addition, accelerated aging tests suggest high energy blue emission from a halogen-free cyclometalated platinum complex could demonstrate degradation rates comparable to known stable emitters. Finally, a buckling based metrology is applied to characterize the mechanical properties of small molecule organic thin films towards understanding the deposition kinetics responsible for an elastic modulus that is both temperature and thickness dependent. These results could contribute to the viability of organic electronic technology in potentially flexible display and lighting applications. The results also provide insight to organic film growth kinetics responsible for optical, mechanical, and water uptake properties relevant to engineering the next generation of optoelectronic devices.
Kirst, Henning; Melis, Anastasios
2014-01-01
The concept of the Truncated Light-harvesting chlorophyll Antenna (TLA) size, as a tool by which to maximize sunlight utilization and photosynthetic productivity in microalgal mass cultures or high-density plant canopies, is discussed. TLA technology is known to improve sunlight-to-product energy conversion efficiencies and is hereby exemplified by photosynthetic productivity estimates of wild type and a TLA strain under simulated mass culture conditions. Recent advances in the generation of TLA-type mutants by targeting genes of the chloroplast signal-recognition particle (CpSRP) pathway, affecting the thylakoid membrane assembly of light-harvesting proteins, are also summarized. Two distinct CpSRP assembly pathways are recognized, one entailing post-translational, the other a co-translational mechanism. Differences between the post-translational and co-translational integration mechanisms are outlined, as these pertain to the CpSRP-mediated assembly of thylakoid membrane protein complexes in higher plants and green microalgae. The applicability of the CpSRP pathway genes in efforts to generate TLA-type strains with enhanced solar energy conversion efficiency in photosynthesis is evaluated. © 2013.
NASA Astrophysics Data System (ADS)
Solarz, R. W.
1985-02-01
Atomic vapor laster isotope separation (AVLIS) represents the largest-scale potential application of tunable lasers that has received serious attention. The underlying physical principles were identified and optimized, the major technology components were developed, and the integrated enrichment performance of the process was tested. The central physical processes are outlined, progress to date on the technology elements is reviewed, and scaling laws are fomulated. Two primary applications are the production of light-water reactor fuel and the conversion of fuel-grade plutonium to weapons-grade material. A variety of applications exist that all potentially use a common base of AVLIS technology. These include missions such as the enrichment of mercury isotopes to improve fluorescent lamp efficiency, the enrichment of iodine isotopes for medical isotope use, and the cleanup of strontium from defense waste for recovering strontium isotopes for radiothermal mechanical generators. The ability to radidly assess the economic and technical feasibility of each mission is derived from the general applicability of AVLIS physics and AVLIS technology.
Laser-driven electron beam acceleration and future application to compact light sources
NASA Astrophysics Data System (ADS)
Hafz, N.; Jeong, T. M.; Lee, S. K.; Pae, K. H.; Sung, J. H.; Choi, I. W.; Yu, T. J.; Jeong, Y. U.; Lee, J.
2009-07-01
Laser-driven plasma accelerators are gaining much attention by the advanced accelerator community due to the potential these accelerators hold in miniaturizing future high-energy and medium-energy machines. In the laser wakefield accelerator (LWFA), the ponderomotive force of an ultrashort high intensity laser pulse excites a longitudinal plasma wave or bubble. Due to huge charge separation, electric fields created in the plasma bubble can be several orders of magnitude higher than those available in conventional microwave and RF-based accelerator facilities which are limited (up to ˜100 MV/m) by material breakdown. Therefore, if an electron bunch is injected into the bubble in phase with its field, it will gain relativistic energies within an extremely short distance. Here, in the LWFA we show the generation of high-quality and high-energy electron beams up to the GeV-class within a few millimeters of gas-jet plasmas irradiated by tens of terawatt ultrashort laser pulses. Thus we realize approximately four orders of magnitude acceleration gradients higher than available by conventional technology. As a practical application of the stable high-energy electron beam generation, we are planning on injecting the electron beams into a few-meters long conventional undulator in order to realize compact X-ray synchrotron (immediate) and FEL (future) light sources. Stable laser-driven electron beam and radiation devices will surely open a new era in science, medicine and technology and will benefit a larger number of users in those fields.
Thin-Film Solar Cells on Polymer Substrates for Space Power
NASA Technical Reports Server (NTRS)
Hepps, A. F.; McNatt, Jeremiah; Morel, D. L.; Ferckides, C. S.; Jin, M. H.; Orbey, N.; Cushman, M.; Birkmire, R. W.; Shafarman, W. N.; Newton, R.
2004-01-01
Photovoltaic arrays have played a key role in power generation in space. The current technology will continue to evolve but is limited in the important mass specific power metric (MSP or power/weight ratio) because it is based on bulk crystal technology. Solar cells based on thin-film materials offer the promise of much higher MSP and much lower cost. However, for many space applications, a 20% or greater AM0 efficiency (eta) may be required. The leading thin-film materials, amorphous Si, CuInSe, and CdTe have seen significant advances in efficiency over the last decade but will not achieve the required efficiency in the near future. Several new technologies are herein described to maximize both device eta and MSP. We will discuss these technologies in the context of space exploration and commercialization. One novel approach involves the use of very lightweight polyimide substrates. We describe efforts to enable this advance including materials processing and device fabrication and characterization. Another approach involves stacking two cells on top of each other. These tandem devices more effectively utilize solar radiation by passing through non-absorbed longer wavelength light to a narrow-bandgap bottom cell material. Modeling of current devices in tandem format indicates that AM0 efficiencies near 20% can be achieved with potential for 25% in the near future. Several important technical issues need to be resolved to realize the benefits of lightweight technologies for solar arrays, such as: monolithic interconnects, lightweight array structures, and new ultra-light support and deployment mechanisms. Recent advances will be stressed.
CPV plants data analysis. ISFOC and NACIR projects results
NASA Astrophysics Data System (ADS)
Martínez, M.; Rubio, F.; Sala, G.; Pachón, D.; Bett, A.; Siefer, G.; Vetter, M.; Schies, A.; Wachtel, J.; Gombert, A.; Wüllner, J.; Díaz, V.; Vázquez, M. A.; Abulfotuh, F.; Fetyan, K.; el Moussaoui, A.; Mansouri, S.; Loudiyi, K.; Darhmaoui, H.; Mrabti, T.
2012-10-01
Now it is the moment for CPV to become a reliable solution for large scale electricity generation, because it is one of the technologies with higher efficiency, and moreover, it has still margin for improvement. In order to continue with this development, it is important to introduce, in the design of the installations, all the lessons learned during the operation of pilot plants. This paper presents the operation results obtained at the ISFOC pilot plants, during the first three and a half years of operation, and the NACIR project. The CPV technology is not demonstrating signs of degradation which could reduce its high capability of transforming light into electricity. From the operation issues, valuable information is obtained in order to improve the design, turning CPV prototypes into an industrialized product ready to compete with other technologies, making a great effort in the reduction of the installation costs.
[Mental health care technologies for treating crack users].
Nasi, Cintia; de Oliveira, Gustavo Costa; Lacchini, Annie Jeanninne Bisso; Schneider, Jacó Fernando; de Pinho, Leandro Barbosa
2015-03-01
The aim of this study was to identify mental health care technologies for treating crack users in a Psychosocial Care Center for Alcohol and other Drugs (CAPsad, as per its acronym in Portuguese). A qualitative, evaluative case study was developed in a CAPSad, using fourth generation evaluation. Data collection occurred from January to March 2013 by means of semi-structured interviews applied to 36 subjects, these being health care professionals, patients, patients' relatives and managers. Data analysis identified the category strategies in mental health work. Results showed that recovery programs should provide spaces for dialogue, aiming to clarify the process of psychiatric internment to the user and family, and involve these in the therapy, implementing educational practices and ongoing consideration of mental health activities. In conclusion, it is important to discuss the technologies used in everyday care services, in light of the complexity of crack use.
He, Yu-Ming; Liu, Jin; Maier, Sebastian; Emmerling, Monika; Gerhardt, Stefan; Davanço, Marcelo; Srinivasan, Kartik; Schneider, Christian; Höfling, Sven
2017-07-20
Deterministic techniques enabling the implementation and engineering of bright and coherent solid-state quantum light sources are key for the reliable realization of a next generation of quantum devices. Such a technology, at best, should allow one to significantly scale up the number of implemented devices within a given processing time. In this work, we discuss a possible technology platform for such a scaling procedure, relying on the application of nanoscale quantum dot imaging to the pillar microcavity architecture, which promises to combine very high photon extraction efficiency and indistinguishability. We discuss the alignment technology in detail, and present the optical characterization of a selected device which features a strongly Purcell-enhanced emission output. This device, which yields an extraction efficiency of η = (49 ± 4) %, facilitates the emission of photons with (94 ± 2.7) % indistinguishability.
Advancing Transportation through Vehicle Electrification - PHEV
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bazzi, Abdullah; Barnhart, Steven
2014-12-31
FCA US LLC viewed the American Recovery and Reinvestment Act (ARRA) as an historic opportunity to learn about and develop PHEV technologies and create the FCA US LLC engineering center for Electrified Powertrains. The ARRA funding supported FCA US LLC’s light-duty electric drive vehicle and charging infrastructure-testing activities and enabled FCA US LLC to utilize the funding on advancing Plug-in Hybrid Electric Vehicle (PHEV) technologies for production on future programs. FCA US LLC intended to develop the next-generations of electric drive and energy batteries through a properly paced convergence of standards, technology, components and common modules. To support the developmentmore » of a strong, commercially viable supplier base, FCA US LLC also utilized this opportunity to evaluate various designated component and sub-system suppliers. The original proposal of this project was submitted in May 2009 and selected in August 2009. The project ended in December 2014.« less
Anderson, Misti Ault; Giordano, James
2013-04-23
The importance of strong science, technology, engineering, and mathematics education continues to grow as society, medicine, and the economy become increasingly focused and dependent upon bioscientific and technological innovation. New advances in frontier sciences (e.g., genetics, neuroscience, bio-engineering, nanoscience, cyberscience) generate ethical issues and questions regarding the use of novel technologies in medicine and public life. In light of current emphasis upon science, technology, engineering, and mathematics education (at the pre-collegiate, undergraduate, graduate, and professional levels), the pace and extent of advancements in science and biotechnology, the increasingly technological orientation and capabilities of medicine, and the ways that medicine - as profession and practice - can engage such scientific and technological power upon the multi-cultural world-stage to affect the human predicament, human condition, and perhaps nature of the human being, we argue that it is critical that science, technology, engineering, and mathematics education go beyond technical understanding and directly address ethical, legal, social, and public policy implications of new innovations. Toward this end, we propose a paradigm of integrative science, technology, ethics, and policy studies that meets these needs through early and continued educational exposure that expands extant curricula of science, technology, engineering, and mathematics programs from the high school through collegiate, graduate, medical, and post-graduate medical education. We posit a synthetic approach that elucidates the historical, current, and potential interaction of scientific and biotechnological development in addition to the ethico-legal and social issues that are important to educate and sustain the next generation of medical and biomedical professionals who can appreciate, articulate, and address the realities of scientific and biotechnological progress given the shifting architectonics of the global social milieu. We assert that current trends in science, technology, medicine, and global politics dictate that these skills will be necessary to responsibly guide ethically sound employment of science, technology, and engineering advancements in medicine so as to enable more competent and humanitarian practice within an increasingly pluralistic world culture.
New light field camera based on physical based rendering tracing
NASA Astrophysics Data System (ADS)
Chung, Ming-Han; Chang, Shan-Ching; Lee, Chih-Kung
2014-03-01
Even though light field technology was first invented more than 50 years ago, it did not gain popularity due to the limitation imposed by the computation technology. With the rapid advancement of computer technology over the last decade, the limitation has been uplifted and the light field technology quickly returns to the spotlight of the research stage. In this paper, PBRT (Physical Based Rendering Tracing) was introduced to overcome the limitation of using traditional optical simulation approach to study the light field camera technology. More specifically, traditional optical simulation approach can only present light energy distribution but typically lack the capability to present the pictures in realistic scenes. By using PBRT, which was developed to create virtual scenes, 4D light field information was obtained to conduct initial data analysis and calculation. This PBRT approach was also used to explore the light field data calculation potential in creating realistic photos. Furthermore, we integrated the optical experimental measurement results with PBRT in order to place the real measurement results into the virtually created scenes. In other words, our approach provided us with a way to establish a link of virtual scene with the real measurement results. Several images developed based on the above-mentioned approaches were analyzed and discussed to verify the pros and cons of the newly developed PBRT based light field camera technology. It will be shown that this newly developed light field camera approach can circumvent the loss of spatial resolution associated with adopting a micro-lens array in front of the image sensors. Detailed operational constraint, performance metrics, computation resources needed, etc. associated with this newly developed light field camera technique were presented in detail.
2016-11-29
AFRL-AFOSR-VA-TR-2016-0365 Long Wavelength Electromagnetic Light Bullets Generated by a 10.6 micron CO2 Ultrashort Pulsed Source Jerome Moloney...SUBTITLE "Long Wavelength Electromagnetic Light Bullets Generated by a 10.6 micron CO2 Ultrashort Pulsed Source 5a. CONTRACT NUMBER FA9550-15-1-0272 5b...afosr.reports.sgizmo.com/s3/> Subject: Final Report to Dr. Arje Nachman Contract/Grant Title: Long Wavelength Electromagnetic Light Bullets Generated by a 10.6
Fiber Sensor Systems Based on Fiber Laser and Microwave Photonic Technologies
Fu, Hongyan; Chen, Daru; Cai, Zhiping
2012-01-01
Fiber-optic sensors, especially fiber Bragg grating (FBG) sensors are very attractive due to their numerous advantages over traditional sensors, such as light weight, high sensitivity, cost-effectiveness, immunity to electromagnetic interference, ease of multiplexing and so on. Therefore, fiber-optic sensors have been intensively studied during the last several decades. Nowadays, with the development of novel fiber technology, more and more newly invented fiber technologies bring better and superior performance to fiber-optic sensing networks. In this paper, the applications of some advanced photonic technologies including fiber lasers and microwave photonic technologies for fiber sensing applications are reviewed. FBG interrogations based on several kinds of fiber lasers, especially the novel Fourier domain mode locking fiber laser, have been introduced; for the application of microwave photonic technology, examples of microwave photonic filtering utilized as a FBG sensing interrogator and microwave signal generation acting as a transversal loading sensor have been given. Both theoretical analysis and experimental demonstrations have been carried out. The comparison of these advanced photonic technologies for the applications of fiber sensing is carried out and important issues related to the applications have been addressed and the suitable and potential application examples have also been discussed in this paper. PMID:22778591
DOE Office of Scientific and Technical Information (OSTI.GOV)
Farooq, M.O.
1988-01-01
The failure of the standard Growth Approach to economic development to solve the problems of underdevelopment in LDCs has caused an alternative approach, Basic Needs Approach (BNA), to attain prominence in development thought. BNA emphasizes poverty-minimizing growth. Its strategy of direct attack on poverty has better potential for LDCs' development and fulfillment of their populations' basic needs than the trickle-down mechanism of the Growth Approach. BNA requires, among other things, (a) suitable rural financial markets (RFMs) as parts of the overall financial system, and (b) indigenous technological capabilities. The financial system, if it functions as a central element in anmore » institutionalized technology policy, can link technology-related institutions that generate, evaluate, and promote appropriate technologies (ATs) with RFMs that can support adoption and diffusion of ATs in the agro-rural sector. The above argument uses Bangladesh as a case for illustration. In the light of an institutional framework presented, examined, and extended in this dissertation, it is found that Bangladesh currently does not have an institutionalized technology policy. The current organizational framework and policies related to technological development are not conducive to BNA.« less
The NASA Advanced Space Power Systems Project
NASA Technical Reports Server (NTRS)
Mercer, Carolyn R.; Hoberecht, Mark A.; Bennett, William R.; Lvovich, Vadim F.; Bugga, Ratnakumar
2015-01-01
The goal of the NASA Advanced Space Power Systems Project is to develop advanced, game changing technologies that will provide future NASA space exploration missions with safe, reliable, light weight and compact power generation and energy storage systems. The development effort is focused on maturing the technologies from a technology readiness level of approximately 23 to approximately 56 as defined in the NASA Procedural Requirement 7123.1B. Currently, the project is working on two critical technology areas: High specific energy batteries, and regenerative fuel cell systems with passive fluid management. Examples of target applications for these technologies are: extending the duration of extravehicular activities (EVA) with high specific energy and energy density batteries; providing reliable, long-life power for rovers with passive fuel cell and regenerative fuel cell systems that enable reduced system complexity. Recent results from the high energy battery and regenerative fuel cell technology development efforts will be presented. The technical approach, the key performance parameters and the technical results achieved to date in each of these new elements will be included. The Advanced Space Power Systems Project is part of the Game Changing Development Program under NASAs Space Technology Mission Directorate.
Potential Benefits of Manmade Opals Demonstrated for First Time (Fact Sheet)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
NREL experiments show that disordered inverse opals significantly scatter and trap near-infrared light, with possible impact on optoelectronic materials. Inverse opals, familiar in the form of brilliantly colored opal gemstones, are a class of materials that has astounding optical properties. Scientists have been exploring the ability of inverse opals to manipulate light in the hopes of harnessing this capacity for advanced technologies such as displays, detectors, lasers, and photovoltaics. A research group at the National Renewable Energy Laboratory (NREL) discovered that man-made inverse opal films containing significant morphological disorder exhibit substantial light scattering, consequently trapping wavelengths in the near-infrared (NIR),more » which is important to a number of technologies. This discovery is the first experimental evidence to validate a 2005 theoretical model predicting the confinement of light in such structures, and it holds great promise for improving the performance of technologies that rely on careful light control. This breakthrough also makes possible optoelectronic technologies that use a range of low-cost molecular and semiconductor species that otherwise absorb light too weakly to be useful. The disordered inverse opal architecture validates the theoretical model that predicts the diffusion and confinement of light in such structures. Electrochemically deposited CdSe inverse opal films containing significant morphological disorder exhibit substantial light scattering and consequent NIR light trapping. This discovery holds promise for NIR light management in optoelectronic technologies, particularly those involving weakly absorbing molecular and semiconductor photomaterials.« less
Superluminescent light emitting diodes: the best out of two worlds
NASA Astrophysics Data System (ADS)
Rossetti, M.; Napierala, J.; Matuschek, N.; Achatz, U.; Duelk, M.; Vélez, C.; Castiglia, A.; Grandjean, N.; Dorsaz, J.; Feltin, E.
2012-03-01
Since pico-projectors were starting to become the next electronic "must-have" gadget, the experts were discussing which light-source technology seems to be the best for the existing three major projection approaches for the optical scanning module such as digital light processing, liquid crystal on silica and laser beam steering. Both so-far used light source technologies have distinct advantages and disadvantages. Though laser-based pico-projectors are focus-free and deliver a wider color gamut, their major disadvantages are speckle noise, cost and safety issues. In contrast, projectors based on cheaper Light Emitting Diodes (LEDs) as light source are criticized for a lack of brightness and for having limited focus. Superluminescent Light Emitting Diodes (SLEDs) are temporally incoherent and spatially coherent light sources merging in one technology the advantages of both Laser Diodes (LDs) and LEDs. With almost no visible speckle noise, focus-free operation and potentially the same color gamut than LDs, SLEDs could potentially answer the question which light source to use in future projector applications. In this quest for the best light source, we realized visible SLEDs emitting both in the red and blue spectral region. While the technology required for the realization of red emitters is already well established, III-nitride compounds required for blue emission have experienced a major development only in relatively recent times and the technology is still under development. The present paper is a review of the status of development reached for the blue superluminescent diodes based on the GaN material system.
Chowdhury, Pankaj; Gomaa, Hassan; Ray, Ajay K
2015-02-01
In this paper, we have studied Eosin Y-sensitized sacrificial hydrogen generation with triethanolamine as electron donor in UV, visible, and solar light irradiation. Aeroxide TiO2 was loaded with platinum metal via solar photo-deposition method to reduce the electron hole recombination process. Photocatalytic sacrificial hydrogen generation was influenced by several factors such as platinum loading (wt%) on TiO2, solution pH, Eosin Y to Pt/TiO2 mass ratio, triethanolamine concentration, and light (UV, visible and solar) intensities. Detailed reaction mechanisms in visible and solar light irradiation were established. Oxidation of triethanolamine and formaldehyde formation was correlated with hydrogen generation in both visible and solar lights. Hydrogen generation kinetics followed a Langmuir-type isotherm with reaction rate constant and adsorption constant of 6.77×10(-6) mol min(-1) and 14.45 M(-1), respectively. Sacrificial hydrogen generation and charge recombination processes were studied as a function of light intensities. Apparent quantum yields (QYs) were compared for UV, visible, and solar light at four different light intensities. Highest QYs were attained at lower light intensity because of trivial charge recombination. At 30 mW cm(-2) we achieved QYs of 10.82%, 12.23% and 11.33% in UV, visible and solar light respectively. Copyright © 2014 Elsevier Ltd. All rights reserved.
New power politics will determine generation's path
DOE Office of Scientific and Technical Information (OSTI.GOV)
Maize, K.; Neville, A.; Peltier, R.
2009-01-15
The US power industry's story in 2009 will be all about change, to borrow a now-familiar theme. Though the new administration's policy specifics had not been revealed as this report was prepared, it appears that flat load growth in 2009 will give the new Obama administration a unique opportunity to formulate new energy policy without risking that the lights will go out. New coal projects are now facing increasing difficulties. It looks as though the electricity supply industry will continue to muddle through. It may see an advancement in infrastructure investment, significant new generation or new technology development. It alsomore » faces the possibility that policies necessary to achieving those goals will not materialize, for political and economic reasons. 4 figs.« less
Village microgrids: The Chile project
DOE Office of Scientific and Technical Information (OSTI.GOV)
Baring-Gould, E.I.
1997-12-01
This paper describes a village application in Chile. The objective was to demonstrate the technical, economic and institutional viability of renewable energy for rural electrification, as well as to allow local partners to gain experience with hybrid/renewable technology, resource assessment, system siting and operation. A micro-grid system is viewed as a small village system, up to 1200 kWh/day load with a 50 kW peak load. It can consist of components of wind, photovoltaic, batteries, and conventional generators. It is usually associated with a single generator source, and uses batteries to cover light day time loads. This paper looks at themore » experiences learned from this project with regard to all of the facets of planning and installing this project.« less
NASA Astrophysics Data System (ADS)
Wang, Fuyin; Xie, Jiehui; Hu, Zhengliang; Xiong, Shuidong; Luo, Hong; Hu, Yongming
2014-05-01
Study of fiber optic extrinsic Fabry-Pérot sensors utilizing state-of-the-art MEMS technology mostly focus on sensor fabrication for various applications, while the signal interrogation is still insatiable to current application. In this paper, we propose a white light path matched differential interferometer dynamic sensing system utilizing phase generated carrier demodulation scheme. A step motor with a movable mirror and a fiber-wound piezoelectric transducer string are used to act path matching and phase modulation respectively. Experimental results show that the sensing signal could be correctly recovered with low distortion and the phase noise spectrum level is less than -100 dB re. rad/√Hz above 2.5 kHz.
NASA Astrophysics Data System (ADS)
Yoshioka, Toshie; Miyoshi, Takashi; Takaya, Yasuhiro
2005-12-01
To realize high productivity and reliability of the semiconductor, patterned wafers inspection technology to maintain high yield becomes essential in modern semiconductor manufacturing processes. As circuit feature is scaled below 100nm, the conventional imaging and light scattering methods are impossible to apply to the patterned wafers inspection technique, because of diffraction limit and lower S/N ratio. So, we propose a new particle detection method using annular evanescent light illumination. In this method, a converging annular light used as a light source is incident on a micro-hemispherical lens. When the converging angle is larger than critical angle, annular evanescent light is generated under the bottom surface of the hemispherical lens. Evanescent light is localized near by the bottom surface and decays exponentially away from the bottom surface. So, the evanescent light selectively illuminates the particles on the patterned wafer surface, because it can't illuminate the patterned wafer surface. The proposed method evaluates particles on a patterned wafer surface by detecting scattered evanescent light distribution from particles. To analyze the fundamental characteristics of the proposed method, the computer simulation was performed using FDTD method. The simulation results show that the proposed method is effective for detecting 100nm size particle on patterned wafer of 100nm lines and spaces, particularly under the condition that the evanescent light illumination with p-polarization and parallel incident to the line orientation. Finally, the experiment results suggest that 220nm size particle on patterned wafer of about 200nm lines and spaces can be detected.
LED lighting efficacy: Status and directions
Morgan Pattison, Paul; Hansen, Monica; Tsao, Jeffrey Y.
2017-12-28
A monumental shift from conventional lighting technologies (incandescent, fluorescent, high intensity discharge) to LED lighting is currently transpiring. The primary driver for this shift has been energy and associated cost savings. LED lighting is now more efficacious than any of the conventional lighting technologies with room to still improve. Near term, phosphor converted LED packages have the potential for efficacy improvement from 160 lm/W to 255 lm/W. Longer term, color-mixed LED packages have the potential for efficacy levels conceivably as high as 330 lm/W, though reaching these performance levels requires breakthroughs in green and amber LED efficiency. LED package efficacymore » sets the upper limit to luminaire efficacy, with the luminaire containing its own efficacy loss channels. In this paper, based on analyses performed through the U.S. Department of Energy Solid State Lighting Program, various LED and luminaire loss channels are elucidated, and critical areas for improvement identified. Beyond massive energy savings, LED technology enables a host of new applications and added value not possible or economical with previous lighting technologies. These include connected lighting, lighting tailored for human physiological responses, horticultural lighting, and ecologically conscious lighting. Finally, none of these new applications would be viable if not for the high efficacies that have been achieved, and are themselves just the beginning of what LED lighting can do.« less
LED lighting efficacy: Status and directions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Morgan Pattison, Paul; Hansen, Monica; Tsao, Jeffrey Y.
A monumental shift from conventional lighting technologies (incandescent, fluorescent, high intensity discharge) to LED lighting is currently transpiring. The primary driver for this shift has been energy and associated cost savings. LED lighting is now more efficacious than any of the conventional lighting technologies with room to still improve. Near term, phosphor converted LED packages have the potential for efficacy improvement from 160 lm/W to 255 lm/W. Longer term, color-mixed LED packages have the potential for efficacy levels conceivably as high as 330 lm/W, though reaching these performance levels requires breakthroughs in green and amber LED efficiency. LED package efficacymore » sets the upper limit to luminaire efficacy, with the luminaire containing its own efficacy loss channels. In this paper, based on analyses performed through the U.S. Department of Energy Solid State Lighting Program, various LED and luminaire loss channels are elucidated, and critical areas for improvement identified. Beyond massive energy savings, LED technology enables a host of new applications and added value not possible or economical with previous lighting technologies. These include connected lighting, lighting tailored for human physiological responses, horticultural lighting, and ecologically conscious lighting. Finally, none of these new applications would be viable if not for the high efficacies that have been achieved, and are themselves just the beginning of what LED lighting can do.« less
NRC Licensing Status Summary Report for NGNP
DOE Office of Scientific and Technical Information (OSTI.GOV)
Moe, Wayne Leland; Kinsey, James Carl
2014-11-01
The Next Generation Nuclear Plant (NGNP) Project, initiated at Idaho National Laboratory (INL) by the U.S. Department of Energy (DOE) pursuant to provisions of the Energy Policy Act of 2005, is based on research and development activities supported by the Department of Energy Generation IV Nuclear Energy Systems Initiative. The principal objective of the NGNP Project is to support commercialization of high temperature gas-cooled reactor (HTGR) technology. The HTGR is a helium-cooled and graphite moderated reactor that can operate at temperatures much higher than those of conventional light water reactor (LWR) technologies. The NGNP will be licensed for construction andmore » operation by the Nuclear Regulatory Commission (NRC). However, not all elements of current regulations (and their related implementation guidance) can be applied to HTGR technology at this time. Certain policies established during past LWR licensing actions must be realigned to properly accommodate advanced HTGR technology. A strategy for licensing HTGR technology was developed and executed through the cooperative effort of DOE and the NRC through the NGNP Project. The purpose of this report is to provide a snapshot of the current status of the still evolving pre-license application regulatory framework relative to commercial HTGR technology deployment in the U.S. The following discussion focuses on (1) describing what has been accomplished by the NGNP Project up to the time of this report, and (2) providing observations and recommendations concerning actions that remain to be accomplished to enable the safe and timely licensing of a commercial HTGR facility in the U.S.« less
Education and Technology: Critical Perspectives, Possible Futures
ERIC Educational Resources Information Center
Kritt, David W., Ed.; Winegar, Lucien T., Ed.
2007-01-01
This book offers a truly learner-centered and learning-centered approach to educational technology. In substantial and interdisciplinary ways it carefully builds a foundation not just for rethinking the potential for technology in light of educational principles but, more importantly, rethinking teaching and learning in light of technology's…
NASA Astrophysics Data System (ADS)
Ito, Yoshitaka; Mizoshiri, Mizue; Mikami, Masashi; Kondo, Tasuku; Sakurai, Junpei; Hata, Seiichi
2017-06-01
We designed and fabricated thin-film thermoelectric generators (TEGs) with ball lenses, which separated visible light and near-infrared (NIR) solar light using a chromatic aberration. The transmitted visible light was used as daylight and the NIR light was used for thermoelectric generation. Solar light was estimated to be separated into the visible light and NIR light by a ray tracing method. 92.7% of the visible light was used as daylight and 9.9% of the NIR light was used for thermoelectric generation. Then, the temperature difference of the pn junctions of the TEG surface was 0.71 K, determined by heat conduction analysis using a finite element method. The thin-film TEGs were fabricated using lithography and deposition processes. When the solar light (A.M. 1.5) was irradiated to the TEGs, the open-circuit voltage and maximum power were 4.5 V/m2 and 51 µW/m2, respectively. These TEGs are expected to be used as an energy supply for Internet of Things sensors.
Guzzinati, Giulio; Béché, Armand; Lourenço-Martins, Hugo; Martin, Jérôme; Kociak, Mathieu; Verbeeck, Jo
2017-01-01
Plasmonics, the science and technology of the interaction of light with metallic objects, is fundamentally changing the way we can detect, generate and manipulate light. Although the field is progressing swiftly, thanks to the availability of nanoscale manufacturing and analysis methods, fundamental properties such as the plasmonic excitations' symmetries cannot be accessed directly, leading to a partial, sometimes incorrect, understanding of their properties. Here we overcome this limitation by deliberately shaping the wave function of an electron beam to match a plasmonic excitations' symmetry in a modified transmission electron microscope. We show experimentally and theoretically that this offers selective detection of specific plasmon modes within metallic nanoparticles, while excluding modes with other symmetries. This method resembles the widespread use of polarized light for the selective excitation of plasmon modes with the advantage of locally probing the response of individual plasmonic objects and a far wider range of symmetry selection criteria. PMID:28401942
Fukagawa, Hirohiko; Shimizu, Takahisa; Kamada, Taisuke; Yui, Shota; Hasegawa, Munehiro; Morii, Katsuyuki; Yamamoto, Toshihiro
2015-01-01
Organic light-emitting diodes (OLEDs) have been intensively studied as a key technology for next-generation displays and lighting. The efficiency of OLEDs has improved markedly in the last 15 years by employing phosphorescent emitters. However, there are two main issues in the practical application of phosphorescent OLEDs (PHOLEDs): the relatively short operational lifetime and the relatively high cost owing to the costly emitter with a concentration of about 10% in the emitting layer. Here, we report on our success in resolving these issues by the utilization of thermally activated delayed fluorescent materials, which have been developed in the past few years, as the host material for the phosphorescent emitter. Our newly developed PHOLED employing only 1 wt% phosphorescent emitter exhibits an external quantum efficiency of over 20% and a long operational lifetime of about 20 times that of an OLED consisting of a conventional host material and 1 wt% phosphorescent emitter. PMID:25985084
Optogenetic control of contractile function in skeletal muscle
Bruegmann, Tobias; van Bremen, Tobias; Vogt, Christoph C.; Send, Thorsten; Fleischmann, Bernd K.; Sasse, Philipp
2015-01-01
Optogenetic stimulation allows activation of cells with high spatial and temporal precision. Here we show direct optogenetic stimulation of skeletal muscle from transgenic mice expressing the light-sensitive channel Channelrhodopsin-2 (ChR2). Largest tetanic contractions are observed with 5-ms light pulses at 30 Hz, resulting in 84% of the maximal force induced by electrical stimulation. We demonstrate the utility of this approach by selectively stimulating with a light guide individual intralaryngeal muscles in explanted larynges from ChR2-transgenic mice, which enables selective opening and closing of the vocal cords. Furthermore, systemic injection of adeno-associated virus into wild-type mice provides sufficient ChR2 expression for optogenetic opening of the vocal cords. Thus, direct optogenetic stimulation of skeletal muscle generates large force and provides the distinct advantage of localized and cell-type-specific activation. This technology could be useful for therapeutic purposes, such as restoring the mobility of the vocal cords in patients suffering from laryngeal paralysis. PMID:26035411
Switchable Materials for Smart Windows.
Wang, Yang; Runnerstrom, Evan L; Milliron, Delia J
2016-06-07
This article reviews the basic principles of and recent developments in electrochromic, photochromic, and thermochromic materials for applications in smart windows. Compared with current static windows, smart windows can dynamically modulate the transmittance of solar irradiation based on weather conditions and personal preferences, thus simultaneously improving building energy efficiency and indoor human comfort. Although some smart windows are commercially available, their widespread implementation has not yet been realized. Recent advances in nanostructured materials provide new opportunities for next-generation smart window technology owing to their unique structure-property relations. Nanomaterials can provide enhanced coloration efficiency, faster switching kinetics, and longer lifetime. In addition, their compatibility with solution processing enables low-cost and high-throughput fabrication. This review also discusses the importance of dual-band modulation of visible and near-infrared (NIR) light, as nearly 50% of solar energy lies in the NIR region. Some latest results show that solution-processable nanostructured systems can selectively modulate the NIR light without affecting the visible transmittance, thus reducing energy consumption by air conditioning, heating, and artificial lighting.
Polarimetric Multispectral Imaging Technology
NASA Technical Reports Server (NTRS)
Cheng, L.-J.; Chao, T.-H.; Dowdy, M.; Mahoney, C.; Reyes, G.
1993-01-01
The Jet Propulsion Laboratory is developing a remote sensing technology on which a new generation of compact, lightweight, high-resolution, low-power, reliable, versatile, programmable scientific polarimetric multispectral imaging instruments can be built to meet the challenge of future planetary exploration missions. The instrument is based on the fast programmable acousto-optic tunable filter (AOTF) of tellurium dioxide (TeO2) that operates in the wavelength range of 0.4-5 microns. Basically, the AOTF multispectral imaging instrument measures incoming light intensity as a function of spatial coordinates, wavelength, and polarization. Its operation can be in either sequential, random access, or multiwavelength mode as required. This provides observation flexibility, allowing real-time alternation among desired observations, collecting needed data only, minimizing data transmission, and permitting implementation of new experiments. These will result in optimization of the mission performance with minimal resources. Recently we completed a polarimetric multispectral imaging prototype instrument and performed outdoor field experiments for evaluating application potentials of the technology. We also investigated potential improvements on AOTF performance to strengthen technology readiness for applications. This paper will give a status report on the technology and a prospect toward future planetary exploration.
Wakefield, Andrew; Broyles, Moth; Stone, Emma L; Jones, Gareth; Harris, Stephen
2016-11-01
LED lighting is predicted to constitute 70% of the outdoor and residential lighting markets by 2020. While the use of LEDs promotes energy and cost savings relative to traditional lighting technologies, little is known about the effects these broad-spectrum "white" lights will have on wildlife, human health, animal welfare, and disease transmission. We conducted field experiments to compare the relative attractiveness of four commercially available "domestic" lights, one traditional (tungsten filament) and three modern (compact fluorescent, "cool-white" LED and "warm-white" LED), to aerial insects, particularly Diptera. We found that LEDs attracted significantly fewer insects than other light sources, but found no significant difference in attraction between the "cool-" and "warm-white" LEDs. Fewer flies were attracted to LEDs than alternate light sources, including fewer Culicoides midges (Diptera: Ceratopogonidae). Use of LEDs has the potential to mitigate disturbances to wildlife and occurrences of insect-borne diseases relative to competing lighting technologies. However, we discuss the risks associated with broad-spectrum lighting and net increases in lighting resulting from reduced costs of LED technology.
Efficient and bright organic light-emitting diodes on single-layer graphene electrodes
NASA Astrophysics Data System (ADS)
Li, Ning; Oida, Satoshi; Tulevski, George S.; Han, Shu-Jen; Hannon, James B.; Sadana, Devendra K.; Chen, Tze-Chiang
2013-08-01
Organic light-emitting diodes are emerging as leading technologies for both high quality display and lighting. However, the transparent conductive electrode used in the current organic light-emitting diode technologies increases the overall cost and has limited bendability for future flexible applications. Here we use single-layer graphene as an alternative flexible transparent conductor, yielding white organic light-emitting diodes with brightness and efficiency sufficient for general lighting. The performance improvement is attributed to the device structure, which allows direct hole injection from the single-layer graphene anode into the light-emitting layers, reducing carrier trapping induced efficiency roll-off. By employing a light out-coupling structure, phosphorescent green organic light-emitting diodes exhibit external quantum efficiency >60%, while phosphorescent white organic light-emitting diodes exhibit external quantum efficiency >45% at 10,000 cd m-2 with colour rendering index of 85. The power efficiency of white organic light-emitting diodes reaches 80 lm W-1 at 3,000 cd m-2, comparable to the most efficient lighting technologies.
Etxeberria, Ed; Gonzalez, Pedro; Fanton Borges, Ana; Brodersen, Craig
2016-01-01
Premise of the study: Uptake of foliar-applied substances across the leaf cuticle is central to world food production as well as for physiological investigations into phloem structure and function. Yet, despite the presence of stomata, foliar application as a delivery system can be extremely inefficient due to the low permeability of leaf surfaces to polar compounds. Methods: Using laser light to generate microscopic perforations in the leaf cuticle, we tested the penetration of several substances into the leaf, their uptake into the phloem, and their subsequent movement through the phloem tissue. Substances varied in their size, charge, and Stokes radius. Results: The phloem-mobile compounds 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxyglucose (2-NBDG), lysine, Biocillin, adenosine triphosphate (ATP), trehalose, carboxyfluorescein-SE, and poly(amidomine) (PAMAM) dendrimer G-4 nanoparticles (4.5 nm in size) showed a high degree of mobility and were able to penetrate and be transported in the phloem. Discussion: Our investigation demonstrated the effectiveness of laser light technology in enhancing the penetration of foliar-applied substances into citrus leaves. The technology is also applicable to the study of phloem mobility of substances by providing a less invasive, highly repeatable, and more quantifiable delivery method. The implied superficial lesions to the leaf can be mitigated by applying a waxy coating. PMID:26819863
Long-Wave Infrared Thermophotonic Imaging of Demineralization in Dental Hard Tissue
NASA Astrophysics Data System (ADS)
Ojaghi, A.; Parkhimchyk, A.; Tabatabaei, N.
2016-08-01
Dental caries remains the most prevalent chronic disease in both children and adults worldwide. To address this prevalence through disease prevention and management, dentists need tools capable of detecting caries at early stages of formation. Looking into the physics of light propagation in teeth, this study presents a clinically and commercially viable platform technology for thermophotonic detection of early dental caries using an inexpensive long-wavelength infrared (LWIR; 8 μm to 14 μm) camera. The developed system incorporates intensity-modulated light to generate a thermal-wave field inside enamel and uses the subsequent infrared emission of the thermal-wave field to detect early caries. It was found that the greater light absorption at caries sites shifts the thermal-wave field centroid, providing contrast between early caries and intact enamel. Use of LWIR detection band in dental samples is novel and beneficial over the conventional mid-wavelength infrared band (3 μm to 5 μm) as it suppresses the masking effect of the instantaneous radiative emission from subsurface features due to the minimal transmittance of enamel in the LWIR band. The efficacy of the LWIR system is verified though experiments carried out on nonbiological test samples as well as on teeth with natural and artificially induced caries. The results suggest that the developed LWIR technology is an affordable early dental caries detection system suitable for commercialization/translation to Dentistry.
NASA-UVA Light Aerospace Alloy and Structures Technology program (LA2ST)
NASA Technical Reports Server (NTRS)
Starke, Edgar A., Jr.; Gangloff, Richard P.; Herakovich, Carl T.; Scully, John R.; Shiflet, Gary J.; Stoner, Glenn E.; Wert, John A.
1995-01-01
The objective of the LA2ST Program is to conduct interdisciplinary graduate student research on the performance of next generation, light-weight aerospace alloys, composites, and thermal gradient structures in collaboration with NASA-Langley researchers. The general aim is to produce relevant data and basic understanding of material mechanical response, environment/corrosion behavior, and microstructure; new monolithic and composite alloys; advanced processing methods; new solid and fluid mechanics analyses; measurement and modeling advances; and a pool of educated students for aerospace technologies. Specific technical objectives are presented for each of the following research projects: time-temperature dependent fracture in advanced wrought ingot metallurgy, and spray deposited aluminum alloys; cryogenic temperature effects on the deformation and fracture of Al-Li-Cu-In alloys; effects of aging and temperature on the ductile fracture of AA2095 and AA2195; mechanisms of localized corrosion in alloys 2090 and 2095; hydrogen interactions in aluminum-lithium alloys 2090 and selected model alloys; mechanisms of deformation and fracture in high strength titanium alloys (effects of temperature and hydrogen and effects of temperature and microstructure); evaluations of wide-panel aluminum alloy extrusions; Al-Si-Ge alloy development; effects of texture and precipitates on mechanical property anisotropy of Al-Cu-Mg-X alloys; damage evolution in polymeric composites; and environmental effects in fatigue life prediction - modeling crack propagation in light aerospace alloys.
Next-generation mid-infrared sources
NASA Astrophysics Data System (ADS)
Jung, D.; Bank, S.; Lee, M. L.; Wasserman, D.
2017-12-01
The mid-infrared (mid-IR) is a wavelength range with a variety of technologically vital applications in molecular sensing, security and defense, energy conservation, and potentially in free-space communication. The recent development and rapid commercialization of new coherent mid-infrared sources have spurred significant interest in the development of mid-infrared optical systems for the above applications. However, optical systems designers still do not have the extensive optical infrastructure available to them that exists at shorter wavelengths (for instance, in the visible and near-IR/telecom wavelengths). Even in the field of optoelectronic sources, which has largely driven the growing interest in the mid-infrared, the inherent limitations of state-of-the-art sources and the gaps in spectral coverage offer opportunities for the development of new classes of lasers, light emitting diodes and emitters for a range of potential applications. In this topical review, we will first present an overview of the current state-of-the-art mid-IR sources, in particular thermal emitters, which have long been utilized, and the relatively new quantum- and interband-cascade lasers, as well as the applications served by these sources. Subsequently, we will discuss potential mid-infrared applications and wavelength ranges which are poorly served by the current stable of mid-IR sources, with an emphasis on understanding the fundamental limitations of the current source technology. The bulk of the manuscript will then explore both past and recent developments in mid-infrared source technology, including narrow bandgap quantum well lasers, type-I and type-II quantum dot materials, type-II superlattices, highly mismatched alloys, lead-salts and transition-metal-doped II-VI materials. We will discuss both the advantages and limitations of each of the above material systems, as well as the potential new applications which they might serve. All in all, this topical review does not aim to provide a survey of the current state of the art for mid-IR sources, but instead looks primarily to provide a picture of potential next-generation optical and optoelectronic materials systems for mid-IR light generation.
Overview of telepathology, virtual microscopy, and whole slide imaging: prospects for the future.
Weinstein, Ronald S; Graham, Anna R; Richter, Lynne C; Barker, Gail P; Krupinski, Elizabeth A; Lopez, Ana Maria; Erps, Kristine A; Bhattacharyya, Achyut K; Yagi, Yukako; Gilbertson, John R
2009-08-01
Telepathology, the practice of pathology at a long distance, has advanced continuously since 1986. Today, fourth-generation telepathology systems, so-called virtual slide telepathology systems, are being used for education applications. Both conventional and innovative surgical pathology diagnostic services are being designed and implemented as well. The technology has been commercialized by more than 30 companies in Asia, the United States, and Europe. Early adopters of telepathology have been laboratories with special challenges in providing anatomic pathology services, ranging from the need to provide anatomic pathology services at great distances to the use of the technology to increase efficiency of services between hospitals less than a mile apart. As to what often happens in medicine, early adopters of new technologies are professionals who create model programs that are successful and then stimulate the creation of infrastructure (ie, reimbursement, telecommunications, information technologies, and so on) that forms the platforms for entry of later, mainstream, adopters. The trend at medical schools, in the United States, is to go entirely digital for their pathology courses, discarding their student light microscopes, and building virtual slide laboratories. This may create a generation of pathology trainees who prefer digital pathology imaging over the traditional hands-on light microscopy. The creation of standards for virtual slide telepathology is early in its development but accelerating. The field of telepathology has now reached a tipping point at which major corporations now investing in the technology will insist that standards be created for pathology digital imaging as a value added business proposition. A key to success in teleradiology, already a growth industry, has been the implementation of standards for digital radiology imaging. Telepathology is already the enabling technology for new, innovative laboratory services. Examples include STAT QA surgical pathology second opinions at a distance and a telehealth-enabled rapid breast care service. The innovative bundling of telemammography, telepathology, and teleoncology services may represent a new paradigm in breast care that helps address the serious issue of fragmentation of breast cancer care in the United States and elsewhere. Legal and regulatory issues in telepathology are being addressed and are regarded as a potential catalyst for the next wave of telepathology advances, applications, and implementations.
Photonics Research and Development
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dickson, Elizabeth
During the period August 2005 through October 2009, the UNLV Research Foundation (UNLVRF), a non-profit affiliate of the University of Nevada, Las Vegas (UNLV), in collaboration with UNLV's Colleges of Science and Engineering; Boston University (BU); Oak Ridge National Laboratory (ORNL); and Sunlight Direct, LLC, has managed and conducted a diverse and comprehensive research and development program focused on light-emitting diode (LED) technologies that provide significantly improved characteristics for lighting and display applications. This final technical report provides detailed information on the nature of the tasks, the results of the research, and the deliverables. It is estimated that about fivemore » percent of the energy used in the nation is for lighting homes, buildings and streets, accounting for some 25 percent of the average home's electric bill. However, the figure is significantly higher for the commercial sector. About 60 percent of the electricity for businesses is for lighting. Thus replacement of current lighting with solid-state lighting technology has the potential to significantly reduce this nation's energy consumption by some estimates, possibly as high as 20%. The primary objective of this multi-year R&D project has been to develop and advance lighting technologies to improve national energy conversion efficiencies; reduce heat load; and significantly lower the cost of conventional lighting technologies. The UNLVRF and its partners have specifically focused these talents on (1) improving LED technologies; (2) optimizing hybrid solar lighting, a technology which potentially offers the benefits of blending natural with artificial lighting systems, thus improving energy efficiency; and (3) building a comprehensive academic infrastructure within UNLV which concentrates on photonics R&D. Task researchers have reported impressive progress in (1) the development of quantum dot laser emitting diodes (QDLEDs) which will ultimately improve energy efficiency and lower costs for display and lighting applications (UNLV College of Engineering); (2) advancing green LED technology based on the Indium-Gallium-Nitride system (BU), thus improving conversion efficiencies; (3) employing unique state-of-the-art X-ray, electron and optical spectroscopies with microscopic techniques to learn more about the electronic structure of materials and contacts in LED devices (UNLV College of Science); (4) establishing a UNLV Display Lighting Laboratory staffed with a specialized team of academic researchers, students and industrial partners focused on identifying and implementing engineering solutions for lighting display-related problems; and (5) conducting research, development and demonstration for HSL essential to the resolution of technological barriers to commercialization.« less
Active Matrix OLED Test Report
NASA Technical Reports Server (NTRS)
Salazar, George
2013-01-01
This report focuses on the limited environmental testing of the AMOLED display performed as an engineering evaluation by The NASA Johnson Space Center (JSC)-specifically. EMI. Thermal Vac, and radiation tests. The AMOLED display is an active-matrix Organic Light Emitting Diode (OLED) technology. The testing provided an initial understanding of the technology and its suitability for space applications. Relative to light emitting diode (LED) displays or liquid crystal displays (LCDs), AMOLED displays provide a superior viewing experience even though they are much lighter and smaller, produce higher contrast ratio and richer colors, and require less power to operate than LCDs. However, AMOLED technology has not been demonstrated in a space environment. Therefore, some risks with the technology must be addressed before they can be seriously considered for human spaceflight. The environmental tests provided preliminary performance data on the ability of the display technology to handle some of the simulated induced space/spacecraft environments that an AMOLED display will see during a spacecraft certification test program. This engineering evaluation is part of a Space Act Agreement (SM) between The NASA/JSC and Honeywell International (HI) as a collaborative effort to evaluate the potential use of AMOLED technology for future human spaceflight missions- both government-led and commercial. Under this SM, HI is responsible for doing optical performance evaluation, as well as temperature and touch screen studies. The NASA/JSC is responsible for performing environmental testing comprised of EMI, Thermal Vac, and radiation tests. Additionally, as part of the testing, limited optical data was acquired to assess performance as the display was subjected to the induced environments. The NASA will benefit from this engineering evaluation by understanding AMOLED suitability for future use in space as well as becoming a smarter buyer (or developer) of the technology. HI benefits from the environmental testing results by understanding its performance limitations/shortcomings to improve subsequent generations of AMOLED technology. Note that the AMOLED used in this test was not deSigned for the space environment but rather for commercial/industrial terrestrial applications.
Evolving Our Evaluation of Luminous Environments
NASA Technical Reports Server (NTRS)
Clark, Toni
2016-01-01
The advance in solid state light emitting technologies and optics for lighting and visual communication necessitates the evaluation of how NASA envisions spacecraft lighting architectures and how NASA uses industry standards for the design and evaluation of lighting systems. Current NASA lighting standards and requirements for existing architectures focus on the separate ability of a lighting system to throw light against a surface or the ability of a display system to provide the appropriate visual contrast. This project investigated large luminous surface lamps as an alternative or supplement to overhead lighting. The efficiency of the technology was evaluated for uniformity and power consumption.
Xu, P; Zhao, L N; Lv, X J; Lu, J; Yuan, Y; Zhao, G; Zhu, S N
2009-06-08
1W quasi-white-light source has been generated from a single lithium tantalate with cascaded domain modulation. The quasi-white-light is combined by proper proportion of the red, green and blue laser light. The red and the blue result from a compact self-sum frequency optical parametric oscillation when pumped by a single green laser. The efficiency of quasi-white-light from the green pump reaches 27%. This compact design can be employed not only as a stable and powerful RGB light source but also an effective blue laser generator.
Jiang, Zhen; Xu, Ming; Li, Fuyou; Yu, Yanlei
2013-11-06
A red-light-controllable soft actuator has been achieved, driven by low-power excited triplet-triplet annihilation-based upconversion luminescence (TTA-UCL). First, a red-to-blue TTA-based upconversion system with a high absolute quantum yield of 9.3 ± 0.5% was prepared by utilizing platinum(II) tetraphenyltetrabenzoporphyrin (PtTPBP) as the sensitizer and 9,10-bis(diphenylphosphoryl)anthracene (BDPPA) as the annihilator. In order to be employed as a highly effective phototrigger of photodeformable cross-linked liquid-crystal polymers (CLCPs), the PtTPBP&BDPPA system was incorporated into a rubbery polyurethane film and then assembled with an azotolane-containing CLCP film. The generating assembly film bent toward the light source when irradiated with a 635 nm laser at low power density of 200 mW cm(-2) because the TTA-UCL was effectively utilized by the azotolane moieties in the CLCP film, inducing their trans-cis photoisomerization and an alignment change of the mesogens via an emission-reabsorption process. It is the first example of a soft actuator in which the TTA-UCL is trapped and utilized to create photomechanical effect. Such advantages of using this novel red-light-controllable soft actuator in potential biological applications have also been demonstrated as negligible thermal effect and its excellent penetration ability into tissues. This work not only provides a novel photomanipulated soft actuation material system based on the TTA-UCL technology but also introduces a new technological application of the TTA-based upconversion system in photonic devices.
Theory of low-power ultra-broadband terahertz sideband generation in bi-layer graphene.
Crosse, J A; Xu, Xiaodong; Sherwin, Mark S; Liu, R B
2014-09-24
In a semiconductor illuminated by a strong terahertz (THz) field, optically excited electron-hole pairs can recombine to emit light in a broad frequency comb evenly spaced by twice the THz frequency. Such high-order THz sideband generation is of interest both as an example of extreme nonlinear optics and also as a method for ultrafast electro-optical modulation. So far, this phenomenon has only been observed with large field strengths (~10 kV cm(-1)), an obstacle for technological applications. Here we predict that bi-layer graphene generates high-order sidebands at much weaker THz fields. We find that a THz field of strength 1 kV cm(-1) can produce a high-sideband spectrum of about 30 THz, 100 times broader than in GaAs. The sidebands are generated despite the absence of classical collisions, with the quantum coherence of the electron-hole pairs enabling recombination. These remarkable features lower the barrier to desktop electro-optical modulation at THz frequencies, facilitating ultrafast optical communications.
Generation and multi-octave shaping of mid-infrared intense single-cycle pulses
NASA Astrophysics Data System (ADS)
Krogen, Peter; Suchowski, Haim; Liang, Houkun; Flemens, Noah; Hong, Kyung-Han; Kärtner, Franz X.; Moses, Jeffrey
2017-03-01
The generation of intense mid-infrared (mid-IR) optical pulses with customizable shape and spectra spanning a multiple-octave range of vibrational frequencies is an elusive technological capability. While some recent approaches to mid-IR supercontinuum generation—such as filamentation, multicolour four-wave-mixing and optical rectification—have successfully generated broad spectra, no process has been identified for achieving complex pulse shaping at the generation step. The adiabatic frequency converter allows for a one-to-one transfer of spectral phase through nonlinear frequency conversion over a larger-than-octave-spanning range and with an overall linear phase transfer function. Here, we show that we can convert shaped near-infrared (near-IR) pulses to shaped, energetic, multi-octave-spanning mid-IR pulses lasting only 1.2 optical cycles, and extendable to the sub-cycle regime. We expect this capability to enable a new class of precisely controlled nonlinear interactions in the mid-IR spectral range, from nonlinear vibrational spectroscopy to strong light-matter interactions and single-shot remote sensing.
Atomic physics research with second and third generation synchrotron light sources
DOE Office of Scientific and Technical Information (OSTI.GOV)
Johnson, B.M.
1990-10-01
This contribution to these proceedings is intended to provide an introduction and overview for other contributions on atomic (and related) physics research at existing and planned synchrotron light sources. The emphasis will be on research accomplishments and future opportunities, but a comparison will be given of operating characteristics for first, second, and third generation machines. First generation light sources were built to do research with the primary electron and positron beams, rather than with the synchrotron radiation itself. Second generation machines were specifically designed to be dedicated synchrotron-radiation facilities, with an emphasis on the use of bending-magnet radiation. The newmore » third generation light sources are being designed to optimize radiation from insertion devices, such as undulators and wigglers. Each generation of synchrotron light source offers useful capabilities for forefront research in atomic physics and many other disciplines. 27 refs., 1 fig., 3 tabs.« less
NASA Technical Reports Server (NTRS)
Kryuchkyan, Gagik YU.; Kheruntsyan, Karen V.
1994-01-01
Two schemes of four-wave mixing oscillators with nondegenerate pumps are proposed for above-threehold generation of squeezed light with nonzero mean-field amplitudes. Noise and correlation properties and optical spectra of squeezed-light beams generated in these schemes are discussed.
Handbook for industrial noise control
NASA Technical Reports Server (NTRS)
1981-01-01
The basic principles of sound, measuring techniques, and instrumentation associated with general purpose noise control are discussed. Means for identifying and characterizing a noise problem so that subsequent work may provide the most efficient and cost effective solution are outlined. A methodology for choosing appropriate noise control materials and the proper implementation of control procedures is detailed. The most significant NASA sponsored contributions to the state of the art development of optimum noise control technologies are described including cases in which aeroacoustics and related research have shed some light on ways of reducing noise generation at its source.
NASA Technical Reports Server (NTRS)
Stepniewski, W. Z.; Tarczynski, T.
1992-01-01
The following concepts, based on using open airscrew(s) for VTOL maneuvers, are re-examined in light of current technology: (1) tip-driven helicopters, (2) compound helicopters; and (3) high-speed VTOL aircraft, represented by tiltrotors, tiltwings, retractoplanes and stoppable rotors. Criteria, permitting one to compare performance of aircraft using diverse lifting and propelling methods are established. Determination of currently possible performance, indication of near-future potentials, and comparison of those items with the baseline levels (as represented by contemporary shaft-driven helicopters, first generation tiltrotors, and commercial turboprop fixed-wind aircraft) constitutes bulk of this report.
Multijunction high voltage concentrator solar cells
NASA Technical Reports Server (NTRS)
Valco, G. J.; Kapoor, V. J.; Evans, J. C.; Chai, A.-T.
1981-01-01
The standard integrated circuit technology has been developed to design and fabricate new innovative planar multi-junction solar cell chips for concentrated sunlight applications. This 1 cm x 1 cm cell consisted of several voltage generating regions called unit cells which were internally connected in series within a single chip resulting in high open circuit voltages. Typical open-circuit voltages of 3.6 V and short-circuit currents of 90 ma were obtained at 80 AM1 suns. A dramatic increase in both short circuit current and open circuit voltage with increased light levels was observed.
Handbook for industrial noise control
NASA Astrophysics Data System (ADS)
The basic principles of sound, measuring techniques, and instrumentation associated with general purpose noise control are discussed. Means for identifying and characterizing a noise problem so that subsequent work may provide the most efficient and cost effective solution are outlined. A methodology for choosing appropriate noise control materials and the proper implementation of control procedures is detailed. The most significant NASA sponsored contributions to the state of the art development of optimum noise control technologies are described including cases in which aeroacoustics and related research have shed some light on ways of reducing noise generation at its source.
Parametric Modeling as a Technology of Rapid Prototyping in Light Industry
NASA Astrophysics Data System (ADS)
Tomilov, I. N.; Grudinin, S. N.; Frolovsky, V. D.; Alexandrov, A. A.
2016-04-01
The paper deals with the parametric modeling method of virtual mannequins for the purposes of design automation in clothing industry. The described approach includes the steps of generation of the basic model on the ground of the initial one (obtained in 3D-scanning process), its parameterization and deformation. The complex surfaces are presented by the wireframe model. The modeling results are evaluated with the set of similarity factors. Deformed models are compared with their virtual prototypes. The results of modeling are estimated by the standard deviation factor.
CAALYX: a new generation of location-based services in healthcare.
Boulos, Maged N Kamel; Rocha, Artur; Martins, Angelo; Vicente, Manuel Escriche; Bolz, Armin; Feld, Robert; Tchoudovski, Igor; Braecklein, Martin; Nelson, John; Laighin, Gearóid O; Sdogati, Claudio; Cesaroni, Francesca; Antomarini, Marco; Jobes, Angela; Kinirons, Mark
2007-03-12
Recent advances in mobile positioning systems and telecommunications are providing the technology needed for the development of location-aware tele-care applications. This paper introduces CAALYX--Complete Ambient Assisted Living Experiment, an EU-funded project that aims at increasing older people's autonomy and self-confidence by developing a wearable light device capable of measuring specific vital signs of the elderly, detecting falls and location, and communicating automatically in real-time with his/her care provider in case of an emergency, wherever the older person happens to be, at home or outside.
DUV light source availability improvement via further enhancement of gas management technologies
NASA Astrophysics Data System (ADS)
Riggs, Daniel J.; O'Brien, Kevin; Brown, Daniel J. W.
2011-04-01
The continuous evolution of the semiconductor market necessitates ever-increasing improvements in DUV light source uptime as defined in the SEMI E10 standard. Cymer is developing technologies to exceed current and projected light source availability requirements via significant reduction in light source downtime. As an example, consider discharge chamber gas management functions which comprise a sizable portion of DUV light source downtime. Cymer's recent introduction of Gas Lifetime Extension (GLXTM) as a productivity improvement technology for its DUV lithography light sources has demonstrated noteworthy reduction in downtime. This has been achieved by reducing the frequency of full gas replenishment events from once per 100 million pulses to as low as once per 2 billion pulses. Cymer has continued to develop relevant technologies that target further reduction in downtime associated with light source gas management functions. Cymer's current subject is the development of technologies to reduce downtime associated with gas state optimization (e.g. total chamber gas pressure) and gas life duration. Current gas state optimization involves execution of a manual procedure at regular intervals throughout the lifetime of light source core components. Cymer aims to introduce a product enhancement - iGLXTM - that eliminates the need for the manual procedure and, further, achieves 4 billion pulse gas lives. Projections of uptime on DUV light sources indicate that downtime associated with gas management will be reduced by 70% when compared with GLX2. In addition to reducing downtime, iGLX reduces DUV light source cost of operation by constraining gas usage. Usage of fluorine rich Halogen gas mix has been reduced by 20% over GLX2.
The Technology of LiFi: A Brief Introduction
NASA Astrophysics Data System (ADS)
Ramadhani, E.; Mahardika, G. P.
2018-03-01
Light Fidelity (LiFi) is a Visible Light Communication (VLC) based technology that making a light as a media of communication replacing the cable wire communication. LiFi is evolve to overcome the rate speed in WiFi, while using LiFi the rate speed can reach until 14 Gbps. This paper presents an introduction of the LiFi technology including the architecture, modulation, performance, and the challenges. The result of this paper can be used as a reference and knowledge to develop some of the LiFi technology.
Zheng, Peng; Li, Shuxing; Wang, Le; Zhou, Tian-Liang; You, Shihai; Takeda, Takashi; Hirosaki, Naoto; Xie, Rong-Jun
2018-05-02
As a next-generation high-power lighting technology, laser lighting has attracted great attention in high-luminance applications. However, thermally robust and highly efficient color converters suitable for high-quality laser lighting are scarce. Despite its versatility, the phosphor-in-glass (PiG) has been seldom applied in laser lighting because of its low thermal conductivity. In this work, we develop a unique architecture in which a phosphor-in-glass (PiG) film was directly sintered on a high thermally conductive sapphire substrate coated by one-dimensional photonic crystals. The designed color converter with the composite architecture exhibits a high internal quantum efficiency close to that of the original phosphor powders and an excellent packaging efficiency up to 90%. Furthermore, the PiG film can even be survived under the 11.2 W mm -2 blue laser excitation. Combining blue laser diodes with the YAG-PiG-on-sapphire plate, a uniform white light with a high luminance of 845 Mcd m -2 (luminous flux: 1839 lm), luminous efficacy of 210 lm W -1 , and correlated color temperature of 6504 K was obtained. A high color rendering index of 74 was attained by adding a robust orange or red phosphor layer to the architecture. These outstanding properties meet the standards of vehicle regulations, enabling the PiG films with the composite architecture to be applied in automotive lighting or other high-power and high-luminance laser lighting.
SESAME - A 3rd Generation Synchrotron Light Source for the Middle East
NASA Astrophysics Data System (ADS)
U˝Lkü, Dinçer; Rahighi, Javad; Winick, Herman
2007-01-01
SESAME (Synchrotron-light for Experimental Science and Applications in the Middle East) will be the Middle East's first international research center. It is a cooperative venture by the scientists and governments of the region with founding members Bahrain, Egypt, Israel, Jordan, Pakistan, Palestine Authority, and Turkey. Iran is in the process of finalizing its formal membership. Other countries (Cyprus, Morocco, and the United Arab Emirates) are also expected to join. The permanent Council of member states has full responsibility for the project. Members provide the annual operating budget. Observer countries are Germany, Greece, Italy, Kuwait, Portugal, Russian Federation, Sweden, the UK, and the US. SESAME is being developed under the umbrella of UNESCO. Jordan was selected as the building site. SESAME will offer excellent opportunities for training of Middle East scientists and attract those working abroad to consider returning. SESAME will be a 2.5GeV 3rd Generation light source (emittance 26nm-rad, circumference ~133m), providing excellent performance for structural molecular biology, molecular environmental science, surface and interface science, microelectromechanical devices, x-ray imaging, archaeological microanalysis, and materials characterization. It will cover a broad spectral range from the infrared to hard x-rays and will have 12 straight sections for insertion devices (average length 2.75m). The injector will be the BESSY I 0.8 GeV booster synchrotron which has been given as a gift from Germany. Four committees advise the Council and assist in developing the technical design, beam lines, user community, and scientific Program. The SESAME building, now in construction with funds and a site provided by Jordan, is scheduled for completion in late 2006 after which the BESSY I injector will be installed. First stored beam in the new 2.5 GeV ring is planned for 2009 with six initial beamlines planned. Some beamlines will be built by member countries. Additional funds to purchase components of the new ring and beamlines are being sought from the EU, the US, and other sources. SESAME has benefited greatly from offers by other light source facilities of equipment and training fellowships in both accelerator technology and applications of synchrotron radiation. Details of this, and other aspects of the training program, are given below. It is hoped that in the future fellowship offers will continue to be made by many light source laboratories to further increase the level of experience with accelerator technology and synchrotron light science in preparation for the start of operation of SESAME.
SESAME — A 3rd Generation Synchrotron Light Source for the Middle East
NASA Astrophysics Data System (ADS)
Űlkü, Dinçer; Rahighi, Javad; Winick, Herman
2007-01-01
SESAME (Synchrotron-light for Experimental Science and Applications in the Middle East) will be the Middle East's first international research center. It is a cooperative venture by the scientists and governments of the region with founding members Bahrain, Egypt, Israel, Jordan, Pakistan, Palestine Authority, and Turkey. Iran is in the process of finalizing its formal membership. Other countries (Cyprus, Morocco, and the United Arab Emirates) are also expected to join. The permanent Council of member states has full responsibility for the project. Members provide the annual operating budget. Observer countries are Germany, Greece, Italy, Kuwait, Portugal, Russian Federation, Sweden, the UK, and the US. SESAME is being developed under the umbrella of UNESCO. Jordan was selected as the building site. SESAME will offer excellent opportunities for training of Middle East scientists and attract those working abroad to consider returning. SESAME will be a 2.5GeV 3rd Generation light source (emittance 26nm-rad, circumference ˜133m), providing excellent performance for structural molecular biology, molecular environmental science, surface and interface science, microelectromechanical devices, x-ray imaging, archaeological microanalysis, and materials characterization. It will cover a broad spectral range from the infrared to hard x-rays and will have 12 straight sections for insertion devices (average length 2.75m). The injector will be the BESSY I 0.8 GeV booster synchrotron which has been given as a gift from Germany. Four committees advise the Council and assist in developing the technical design, beam lines, user community, and scientific Program. The SESAME building, now in construction with funds and a site provided by Jordan, is scheduled for completion in late 2006 after which the BESSY I injector will be installed. First stored beam in the new 2.5 GeV ring is planned for 2009 with six initial beamlines planned. Some beamlines will be built by member countries. Additional funds to purchase components of the new ring and beamlines are being sought from the EU, the US, and other sources. SESAME has benefited greatly from offers by other light source facilities of equipment and training fellowships in both accelerator technology and applications of synchrotron radiation. Details of this, and other aspects of the training program, are given below. It is hoped that in the future fellowship offers will continue to be made by many light source laboratories to further increase the level of experience with accelerator technology and synchrotron light science in preparation for the start of operation of SESAME.
SESAME - A 3rd Generation Synchrotron Light Source for the Middle East
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ulkue, Dincer; Rahighi, Javad; Winick, Herman
2007-01-19
SESAME (Synchrotron-light for Experimental Science and Applications in the Middle East) will be the Middle East's first international research center. It is a cooperative venture by the scientists and governments of the region with founding members Bahrain, Egypt, Israel, Jordan, Pakistan, Palestine Authority, and Turkey. Iran is in the process of finalizing its formal membership. Other countries (Cyprus, Morocco, and the United Arab Emirates) are also expected to join. The permanent Council of member states has full responsibility for the project. Members provide the annual operating budget. Observer countries are Germany, Greece, Italy, Kuwait, Portugal, Russian Federation, Sweden, the UK,more » and the US. SESAME is being developed under the umbrella of UNESCO. Jordan was selected as the building site. SESAME will offer excellent opportunities for training of Middle East scientists and attract those working abroad to consider returning. SESAME will be a 2.5GeV 3rd Generation light source (emittance 26nm-rad, circumference {approx}133m), providing excellent performance for structural molecular biology, molecular environmental science, surface and interface science, microelectromechanical devices, x-ray imaging, archaeological microanalysis, and materials characterization. It will cover a broad spectral range from the infrared to hard x-rays and will have 12 straight sections for insertion devices (average length 2.75m). The injector will be the BESSY I 0.8 GeV booster synchrotron which has been given as a gift from Germany. Four committees advise the Council and assist in developing the technical design, beam lines, user community, and scientific Program. The SESAME building, now in construction with funds and a site provided by Jordan, is scheduled for completion in late 2006 after which the BESSY I injector will be installed. First stored beam in the new 2.5 GeV ring is planned for 2009 with six initial beamlines planned. Some beamlines will be built by member countries. Additional funds to purchase components of the new ring and beamlines are being sought from the EU, the US, and other sources. SESAME has benefited greatly from offers by other light source facilities of equipment and training fellowships in both accelerator technology and applications of synchrotron radiation. Details of this, and other aspects of the training program, are given below. It is hoped that in the future fellowship offers will continue to be made by many light source laboratories to further increase the level of experience with accelerator technology and synchrotron light science in preparation for the start of operation of SESAME.« less
Light-duty automotive technology and fuel economy trends : 1975 through 2008
DOT National Transportation Integrated Search
2009-11-01
This report summarizes key trends in carbon dioxide (CO2) emissions, fuel economy and technology usage related to model year (MY) 1975 through 2009 light-duty vehicles sold in the United States. Light-duty vehicles are those vehicles that EPA classif...
Integrative Multi-Spectral Sensor Device for Far-Infrared and Visible Light Fusion
NASA Astrophysics Data System (ADS)
Qiao, Tiezhu; Chen, Lulu; Pang, Yusong; Yan, Gaowei
2018-06-01
Infrared and visible light image fusion technology is a hot spot in the research of multi-sensor fusion technology in recent years. Existing infrared and visible light fusion technologies need to register before fusion because of using two cameras. However, the application effect of the registration technology has yet to be improved. Hence, a novel integrative multi-spectral sensor device is proposed for infrared and visible light fusion, and by using the beam splitter prism, the coaxial light incident from the same lens is projected to the infrared charge coupled device (CCD) and visible light CCD, respectively. In this paper, the imaging mechanism of the proposed sensor device is studied with the process of the signals acquisition and fusion. The simulation experiment, which involves the entire process of the optic system, signal acquisition, and signal fusion, is constructed based on imaging effect model. Additionally, the quality evaluation index is adopted to analyze the simulation result. The experimental results demonstrate that the proposed sensor device is effective and feasible.
Comparative performance analysis of shunt and series passive filter for LED lamp
NASA Astrophysics Data System (ADS)
Sarwono, Edi; Facta, Mochammad; Handoko, Susatyo
2018-03-01
Light Emitting Diode lamp or LED lamp nowadays is widely used by consumers as a new innovation in the lighting technologies due to its energy saving for low power consumption lamps for brighter light intensity. How ever, the LED lamp produce an electric pollutant known as harmonics. The harmonics is generated by rectifier as part of LED lamp circuit. The present of harmonics in current or voltage has made the source waveform from the grid is distorted. This distortion may cause inacurrate measurement, mall function, and excessive heating for any element at the grid. This paper present an analysis work of shunt and series filters to suppress the harmonics generated by the LED lamp circuit. The work was initiated by conducting several tests to investigate the harmonic content of voltage and currents. The measurements in this work were carried out by using HIOKI Power Quality Analyzer 3197. The measurement results showed that the harmonics current of tested LED lamps were above the limit of IEEE standard 519-2014. Based on the measurement results shunt and series filters were constructed as low pass filters. The bode analysis were appled during construction and prediction of the filters performance. Based on experimental results, the application of shunt filter at input side of LED lamp has reduced THD current up to 88%. On the other hand, the series filter has significantly reduced THD current up to 92%.
Chow, Cheuk-Fai; Wong, Wing-Leung; Chan, Ching-Wan; Chan, Chung-Sum
2018-05-01
Better treatment and management strategies than landfilling are needed to address the large quantities of unrecycled plastic waste generated by daily human activities. Waste-to-energy conversion is an ideal benchmark for developing future large-scale waste management technologies. The present study explores a new approach for producing energetic materials by converting inert plastic waste into energy (thermal and mechanical energies) via a light-controlled process through the simple chemical activation of plastic waste, including polyethylene, polypropylene, and polyvinyl chloride. The inert and non-polar polymer surfaces of the plastics were modified by generating a number of sulfonic groups (SO 3 - ) using chlorosulfuric acid, followed by grafting of Fe(III) catalyst onto the polymer chains to obtain activated polymer. Elemental analyses of these activated materials showed that the carbon-to-sulfur ratio ranged from 3:1 to 5:1. The FTIR spectra indicated the presence of CC bonds (v C=C : 1615-1630 cm -1 ) and SO bonds (v S=O : 1151-1167 cm -1 ) in the activated polymers after chemical reaction. These activated materials were energetic, as light could be used to convert them into thermal (1800-3200 J/g) and mechanical energies (380-560 kPa/g) using hydrogen peroxide as the oxidant under ambient conditions within 1 h. Copyright © 2018 Elsevier Ltd. All rights reserved.
Low-picomolar limits of detection using high-power light-emitting diodes for fluorescence.
de Jong, Ebbing P; Lucy, Charles A
2006-05-01
Fluorescence detectors are ever more frequently being used with light-emitting diodes (LEDs) as the light source. Technological advances in the solid-state lighting industry have produced LEDs which are also suitable tools in analytical measurements. LEDs are now available which deliver 700 mW of radiometric power. While this greater light power can increase the fluorescence signal, it is not trivial to make proper use of this light. This new generation of LEDs has a large emitting area and a highly divergent beam. This presents a classic problem in optics where one must choose between either a small focused light spot, or high light collection efficiency. We have selected for light collection efficiency, which yields a light spot somewhat larger than the emitting area of the LED. This light is focused onto a flow cell. Increasing the detector cell internal diameter (i.d.) produces gains in (sensitivity)3. However, since the detector cell i.d. is smaller than the LED spot size, scattering of excitation light towards the detector remains a significant source of background signal. This can be minimized through the use of spectral filters and spatial filters in the form of pinholes. The detector produced a limit of detection (LOD) of 3 pM, which is roughly three orders of magnitude lower than other reports of LED-based fluorescence detectors. Furthermore, this LOD comes within a factor of six of much more expensive laser-based fluorescence systems. This detector has been used to monitor a separation from a gel filtration column of fluorescently labeled BSA from residual labeling reagent. The LOD of fluorescently labeled BSA is 25 pM.
Flear, Mark L; Pickersgill, Martyn D
2013-01-01
'Citizen participation' includes various participatory techniques and is frequently viewed as an unproblematic and important social good when used as part of the regulation of the innovation and implementation of science and technology. This is perhaps especially evident in debates around 'anticipatory governance' or 'upstream engagement'. Here, we interrogate this thesis using the example of the European Union's regulation of emerging health technologies (such as nanotechnology). In this case, citizen participation in regulatory debate is concerned with innovative objects for medical application that are considered to be emergent or not yet concrete. Through synthesising insights from law, regulatory studies, critical theory, and science and technology studies, we seek to cast new light on the promises, paradoxes, and pitfalls of citizen participation as a tool or technology of regulation in itself. As such we aim to generate a new vantage point from which to view the values and sociotechnical imaginaries that are both 'designed-in' and 'designed-out' of citizen participation. In so doing, we show not only how publics (do not) regulate technologies, but also how citizens themselves are regulated through the techniques of participation.
Flear, Mark L.; Pickersgill, Martyn D.
2013-01-01
‘Citizen participation’ includes various participatory techniques and is frequently viewed as an unproblematic and important social good when used as part of the regulation of the innovation and implementation of science and technology. This is perhaps especially evident in debates around ‘anticipatory governance’ or ‘upstream engagement’. Here, we interrogate this thesis using the example of the European Union's regulation of emerging health technologies (such as nanotechnology). In this case, citizen participation in regulatory debate is concerned with innovative objects for medical application that are considered to be emergent or not yet concrete. Through synthesising insights from law, regulatory studies, critical theory, and science and technology studies, we seek to cast new light on the promises, paradoxes, and pitfalls of citizen participation as a tool or technology of regulation in itself. As such we aim to generate a new vantage point from which to view the values and sociotechnical imaginaries that are both ‘designed-in’ and ‘designed-out’ of citizen participation. In so doing, we show not only how publics (do not) regulate technologies, but also how citizens themselves are regulated through the techniques of participation. PMID:23222171