Advanced Physics Labs and Undergraduate Research: Helping Them Work Together

NASA Astrophysics Data System (ADS)

Peterson, Richard W.

2009-10-01

The 2009 Advanced Lab Topical Conference in Ann Arbor affirmed the importance of advanced labs that teach crucial skills and methodologies by carefully conducting a time-honored experiment. Others however argued that such a constrained experiment can play a complementary role to more open-ended, project experiences. A genuine ``experiment'' where neither student or faculty member is exactly sure of the best approach or anticipated result can often trigger real excitement, creativity, and career direction for students while reinforcing the advanced lab and undergraduate research interface. Several examples are cited in areas of AMO physics, optics, fluids, and acoustics. Colleges and universities that have dual-degree engineering, engineering physics, or applied physics programs may especially profit from interdisciplinary projects that utilize optical, electromagnetic, and acoustical measurements in conjunction with computational physics and simulation.

Giant Faraday Rotation in Metal-Fluoride Nanogranular Films.

PubMed

Kobayashi, N; Ikeda, K; Gu, Bo; Takahashi, S; Masumoto, H; Maekawa, S

2018-03-21

Magneto-optical Faraday effect is widely applied in optical devices and is indispensable for optical communications and advanced information technology. However, the bismuth garnet Bi-YIG is only the Faraday material since 1972. Here we introduce (Fe, FeCo)-(Al-,Y-fluoride) nanogranular films exhibiting giant Faraday effect, 40 times larger than Bi-YIG. These films have a nanocomposite structure, in which nanometer-sized Fe, FeCo ferromagnetic granules are dispersed in a Al,Y-fluoride matrix.

Generating Bulk-Scale Ordered Optical Materials Using Shear-Assembly in Viscoelastic Media.

PubMed

Finlayson, Chris E; Baumberg, Jeremy J

2017-06-22

We review recent advances in the generation of photonics materials over large areas and volumes, using the paradigm of shear-induced ordering of composite polymer nanoparticles. The hard-core/soft-shell design of these particles produces quasi-solid "gum-like" media, with a viscoelastic ensemble response to applied shear, in marked contrast to the behavior seen in colloidal and granular systems. Applying an oscillatory shearing method to sub-micron spherical nanoparticles gives elastomeric photonic crystals (or "polymer opals") with intense tunable structural color. The further engineering of this shear-ordering using a controllable "roll-to-roll" process known as Bending Induced Oscillatory Shear (BIOS), together with the interchangeable nature of the base composite particles, opens potentially transformative possibilities for mass manufacture of nano-ordered materials, including advances in optical materials, photonics, and metamaterials/plasmonics.

Generating Bulk-Scale Ordered Optical Materials Using Shear-Assembly in Viscoelastic Media

PubMed Central

Finlayson, Chris E.; Baumberg, Jeremy J.

2017-01-01

We review recent advances in the generation of photonics materials over large areas and volumes, using the paradigm of shear-induced ordering of composite polymer nanoparticles. The hard-core/soft-shell design of these particles produces quasi-solid “gum-like” media, with a viscoelastic ensemble response to applied shear, in marked contrast to the behavior seen in colloidal and granular systems. Applying an oscillatory shearing method to sub-micron spherical nanoparticles gives elastomeric photonic crystals (or “polymer opals”) with intense tunable structural color. The further engineering of this shear-ordering using a controllable “roll-to-roll” process known as Bending Induced Oscillatory Shear (BIOS), together with the interchangeable nature of the base composite particles, opens potentially transformative possibilities for mass manufacture of nano-ordered materials, including advances in optical materials, photonics, and metamaterials/plasmonics. PMID:28773044

Positron annihilation in transparent ceramics

NASA Astrophysics Data System (ADS)

Husband, P.; Bartošová, I.; Slugeň, V.; Selim, F. A.

2016-01-01

Transparent ceramics are emerging as excellent candidates for many photonic applications including laser, scintillation and illumination. However achieving perfect transparency is essential in these applications and requires high technology processing and complete understanding for the ceramic microstructure and its effect on the optical properties. Positron annihilation spectroscopy (PAS) is the perfect tool to study porosity and defects. It has been applied to investigate many ceramic structures; and transparent ceramics field may be greatly advanced by applying PAS. In this work positron lifetime (PLT) measurements were carried out in parallel with optical studies on yttrium aluminum garnet transparent ceramics in order to gain an understanding for their structure at the atomic level and its effect on the transparency and light scattering. The study confirmed that PAS can provide useful information on their microstructure and guide the technology of manufacturing and advancing transparent ceramics.

Applying LED in full-field optical coherence tomography for gastrointestinal endoscopy

NASA Astrophysics Data System (ADS)

Yang, Bor-Wen; Wang, Yu-Yen; Juan, Yu-Shan; Hsu, Sheng-Jie

2015-08-01

Optical coherence tomography (OCT) has become an important medical imaging technology due to its non-invasiveness and high resolution. Full-field optical coherence tomography (FF-OCT) is a scanning scheme especially suitable for en face imaging as it employs a CMOS/CCD device for parallel pixels processing. FF-OCT can also be applied to high-speed endoscopic imaging. Applying cylindrical scanning and a right-angle prism, we successfully obtained a 360° tomography of the inner wall of an intestinal cavity through an FF-OCT system with an LED source. The 10-μm scale resolution enables the early detection of gastrointestinal lesions, which can increase detection rates for esophageal, stomach, or vaginal cancer. All devices used in this system can be integrated by MOEMS technology to contribute to the studies of gastrointestinal medicine and advanced endoscopy technology.

Roadmap on quantum optical systems

NASA Astrophysics Data System (ADS)

Dumke, Rainer; Lu, Zehuang; Close, John; Robins, Nick; Weis, Antoine; Mukherjee, Manas; Birkl, Gerhard; Hufnagel, Christoph; Amico, Luigi; Boshier, Malcolm G.; Dieckmann, Kai; Li, Wenhui; Killian, Thomas C.

2016-09-01

This roadmap bundles fast developing topics in experimental optical quantum sciences, addressing current challenges as well as potential advances in future research. We have focused on three main areas: quantum assisted high precision measurements, quantum information/simulation, and quantum gases. Quantum assisted high precision measurements are discussed in the first three sections, which review optical clocks, atom interferometry, and optical magnetometry. These fields are already successfully utilized in various applied areas. We will discuss approaches to extend this impact even further. In the quantum information/simulation section, we start with the traditionally successful employed systems based on neutral atoms and ions. In addition the marvelous demonstrations of systems suitable for quantum information is not progressing, unsolved challenges remain and will be discussed. We will also review, as an alternative approach, the utilization of hybrid quantum systems based on superconducting quantum devices and ultracold atoms. Novel developments in atomtronics promise unique access in exploring solid-state systems with ultracold gases and are investigated in depth. The sections discussing the continuously fast-developing quantum gases include a review on dipolar heteronuclear diatomic gases, Rydberg gases, and ultracold plasma. Overall, we have accomplished a roadmap of selected areas undergoing rapid progress in quantum optics, highlighting current advances and future challenges. These exciting developments and vast advances will shape the field of quantum optics in the future.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Blansett, Ethan L.; Schroeppel, Richard Crabtree; Tang, Jason D.

With the build-out of large transport networks utilizing optical technologies, more and more capacity is being made available. Innovations in Dense Wave Division Multiplexing (DWDM) and the elimination of optical-electrical-optical conversions have brought on advances in communication speeds as we move into 10 Gigabit Ethernet and above. Of course, there is a need to encrypt data on these optical links as the data traverses public and private network backbones. Unfortunately, as the communications infrastructure becomes increasingly optical, advances in encryption (done electronically) have failed to keep up. This project examines the use of optical logic for implementing encryption in themore » photonic domain to achieve the requisite encryption rates. In order to realize photonic encryption designs, technology developed for electrical logic circuits must be translated to the photonic regime. This paper examines two classes of all optical logic (SEED, gain competition) and how each discrete logic element can be interconnected and cascaded to form an optical circuit. Because there is no known software that can model these devices at a circuit level, the functionality of the SEED and gain competition devices in an optical circuit were modeled in PSpice. PSpice allows modeling of the macro characteristics of the devices in context of a logic element as opposed to device level computational modeling. By representing light intensity as voltage, 'black box' models are generated that accurately represent the intensity response and logic levels in both technologies. By modeling the behavior at the systems level, one can incorporate systems design tools and a simulation environment to aid in the overall functional design. Each black box model of the SEED or gain competition device takes certain parameters (reflectance, intensity, input response), and models the optical ripple and time delay characteristics. These 'black box' models are interconnected and cascaded in an encrypting/scrambling algorithm based on a study of candidate encryption algorithms. We found that a low gate count, cascadable encryption algorithm is most feasible given device and processing constraints. The modeling and simulation of optical designs using these components is proceeding in parallel with efforts to perfect the physical devices and their interconnect. We have applied these techniques to the development of a 'toy' algorithm that may pave the way for more robust optical algorithms. These design/modeling/simulation techniques are now ready to be applied to larger optical designs in advance of our ability to implement such systems in hardware.« less

Using two MEMS deformable mirrors in an adaptive optics test bed for multiconjugate correction

NASA Astrophysics Data System (ADS)

Andrews, Jonathan R.; Martinez, Ty; Teare, Scott W.; Restaino, Sergio R.; Wilcox, Christopher C.; Santiago, Freddie; Payne, Don M.

2010-02-01

Adaptive optics systems have advanced considerably over the past decade and have become common tools for optical engineers. The most recent advances in adaptive optics technology have lead to significant reductions in the cost of most of the key components. Most significantly, the cost of deformable elements and wavefront sensor components have dropped to the point where multiple deformable mirrors and Shack- Hartmann array based wavefront sensor cameras can be included in a single system. Matched with the appropriate hardware and software, formidable systems can be operating in nearly any sized research laboratory. The significant advancement of MEMS deformable mirrors has made them very popular for use as the active corrective element in multi-conjugate adaptive optics systems so that, in particular for astronomical applications, this allows correction in more than one plane. The NRL compact AO system and atmospheric simulation systems has now been expanded to support Multi Conjugate Adaptive Optics (MCAO), taking advantage of using the liquid crystal spatial light modulator (SLM) driven aberration generators in two conjugate planes that are well separated spatially. Thus, by using two SLM based aberration generators and two separate wavefront sensors, the system can measure and apply wavefront correction with two MEMS deformable mirrors. This paper describes the multi-conjugate adaptive optics system and the testing and calibration of the system and demonstrates preliminary results with this system.

Advanced optical sensing and processing technologies for the distributed control of large flexible spacecraft

NASA Technical Reports Server (NTRS)

Williams, G. M.; Fraser, J. C.

1991-01-01

The objective was to examine state-of-the-art optical sensing and processing technology applied to control the motion of flexible spacecraft. Proposed large flexible space systems, such an optical telescopes and antennas, will require control over vast surfaces. Most likely distributed control will be necessary involving many sensors to accurately measure the surface. A similarly large number of actuators must act upon the system. The used technical approach included reviewing proposed NASA missions to assess system needs and requirements. A candidate mission was chosen as a baseline study spacecraft for comparison of conventional and optical control components. Control system requirements of the baseline system were used for designing both a control system containing current off-the-shelf components and a system utilizing electro-optical devices for sensing and processing. State-of-the-art surveys of conventional sensor, actuator, and processor technologies were performed. A technology development plan is presented that presents a logical, effective way to develop and integrate advancing technologies.

Modified surface testing method for large convex aspheric surfaces based on diffraction optics.

PubMed

Zhang, Haidong; Wang, Xiaokun; Xue, Donglin; Zhang, Xuejun

2017-12-01

Large convex aspheric optical elements have been widely applied in advanced optical systems, which have presented a challenging metrology problem. Conventional testing methods cannot satisfy the demand gradually with the change of definition of "large." A modified method is proposed in this paper, which utilizes a relatively small computer-generated hologram and an illumination lens with certain feasibility to measure the large convex aspherics. Two example systems are designed to demonstrate the applicability, and also, the sensitivity of this configuration is analyzed, which proves the accuracy of the configuration can be better than 6 nm with careful alignment and calibration of the illumination lens in advance. Design examples and analysis show that this configuration is applicable to measure the large convex aspheric surfaces.

Polymer planar lightwave circuit based hybrid-integrated coherent receiver for advanced modulation signals

NASA Astrophysics Data System (ADS)

Wang, Jin; Han, Yang; Liang, Zhongcheng; Chen, Yongjin

2012-11-01

Applying coherent detection technique to advanced modulation formats makes it possible to electronically compensate the signal impairments. A key issue for a successful deployment of coherent detection technique is the availability of cost-efficient and compact integrated receivers, which are composed of an optical 90° hybrid mixer and four photodiodes (PDs). In this work, three different types of optical hybrids are fabricated with polymer planar lightwave circuit (PLC), and hybridly integrated with four vertical backside illuminated III-V PDs. Their performances, such as the insertion loss, the transmission imbalance, the polarization dependence and the phase deviation of 90° hybrid will be discussed.

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.

LLIMAS: Revolutionizing integrating modeling and analysis at MIT Lincoln Laboratory

NASA Astrophysics Data System (ADS)

Doyle, Keith B.; Stoeckel, Gerhard P.; Rey, Justin J.; Bury, Mark E.

2017-08-01

MIT Lincoln Laboratory's Integrated Modeling and Analysis Software (LLIMAS) enables the development of novel engineering solutions for advanced prototype systems through unique insights into engineering performance and interdisciplinary behavior to meet challenging size, weight, power, environmental, and performance requirements. LLIMAS is a multidisciplinary design optimization tool that wraps numerical optimization algorithms around an integrated framework of structural, thermal, optical, stray light, and computational fluid dynamics analysis capabilities. LLIMAS software is highly extensible and has developed organically across a variety of technologies including laser communications, directed energy, photometric detectors, chemical sensing, laser radar, and imaging systems. The custom software architecture leverages the capabilities of existing industry standard commercial software and supports the incorporation of internally developed tools. Recent advances in LLIMAS's Structural-Thermal-Optical Performance (STOP), aeromechanical, and aero-optical capabilities as applied to Lincoln prototypes are presented.

Space Optic Manufacturing - X-ray Mirror

NASA Technical Reports Server (NTRS)

1998-01-01

NASA's Space Optics Manufacturing Center has been working to expand our view of the universe via sophisticated new telescopes. The Optics Center's goal is to develop low-cost, advanced space optics technologies for the NASA program in the 21st century - including the long-term goal of imaging Earth-like planets in distant solar systems. To reduce the cost of mirror fabrication, Marshall Space Flight Center (MSFC) has developed replication techniques, the machinery and materials to replicate electro-formed nickel mirrors. The process allows fabricating precisely shaped mandrels to be used and reused as masters for replicating high-quality mirrors. This image shows a lightweight replicated x-ray mirror with gold coatings applied.

A developmental perspective on high power laser facility technology for ICF

NASA Astrophysics Data System (ADS)

Zhu, Jianqiang; Sun, Mingying; Liu, Chong; Guo, Yajing; Yang, Lin; Yang, Pengqian; Zhang, Yanli; Wang, Bingyan; Liu, Cheng; Li, Yangshuai; Ren, Zhiyuan; Liu, Dean; Liu, Zhigang; Jiao, Zhaoyang; Ren, Lei; Zhang, Guowen; Fan, Quantang; Feng, Tao; Lin, Zunqi

2018-02-01

The latest progress on high power laser facilities in NLHPLP was reported. Based on a high power laser prototype, damage behavior of 3ω optics was experimentally tested, and the key influencing factors contributed to laser-induced damage in optics were deeply analyzed. The latest experimental results of advanced precision measurement for optical quality applied in the high power laser facility were introduced. At last, based on the accumulated works of 3ω elements damage behavior status in our laboratory, beam expanding scheme was presented to increase the total maximum output 3ω energy properly and decrease the laser induced damage risking of ω optics simultaneously.

Advancements in Electromagnetic Wave Backscattering Simulations: Applications in Active Lidar Remote Sensing Involving Aerosols

NASA Astrophysics Data System (ADS)

Bi, L.

2016-12-01

Atmospheric remote sensing based on the Lidar technique fundamentally relies on knowledge of the backscattering of light by particulate matters in the atmosphere. This talk starts with a review of the current capabilities of electromagnetic wave scattering simulations to determine the backscattering optical properties of irregular particles, such as the backscatterer and depolarization ratio. This will be followed by a discussion of possible pitfalls in the relevant simulations. The talk will then be concluded with reports on the latest advancements in computational techniques. In addition, we summarize the laws of the backscattering optical properties of aerosols with respect to particle geometries, particle sizes, and mixing rules. These advancements will be applied to the analysis of the Lidar observation data to reveal the state and possible microphysical processes of various aerosols.

New developments of X-ray fluorescence imaging techniques in laboratory

NASA Astrophysics Data System (ADS)

Tsuji, Kouichi; Matsuno, Tsuyoshi; Takimoto, Yuki; Yamanashi, Masaki; Kometani, Noritsugu; Sasaki, Yuji C.; Hasegawa, Takeshi; Kato, Shuichi; Yamada, Takashi; Shoji, Takashi; Kawahara, Naoki

2015-11-01

X-ray fluorescence (XRF) analysis is a well-established analytical technique with a long research history. Many applications have been reported in various fields, such as in the environmental, archeological, biological, and forensic sciences as well as in industry. This is because XRF has a unique advantage of being a nondestructive analytical tool with good precision for quantitative analysis. Recent advances in XRF analysis have been realized by the development of new x-ray optics and x-ray detectors. Advanced x-ray focusing optics enables the making of a micro x-ray beam, leading to micro-XRF analysis and XRF imaging. A confocal micro-XRF technique has been applied for the visualization of elemental distributions inside the samples. This technique was applied for liquid samples and for monitoring chemical reactions such as the metal corrosion of steel samples in the NaCl solutions. In addition, a principal component analysis was applied for reducing the background intensity in XRF spectra obtained during XRF mapping, leading to improved spatial resolution of confocal micro-XRF images. In parallel, the authors have proposed a wavelength dispersive XRF (WD-XRF) imaging spectrometer for a fast elemental imaging. A new two dimensional x-ray detector, the Pilatus detector was applied for WD-XRF imaging. Fast XRF imaging in 1 s or even less was demonstrated for Euro coins and industrial samples. In this review paper, these recent advances in laboratory-based XRF imaging, especially in a laboratory setting, will be introduced.

A plot twist: the continuing story of VCSELs at AOC

NASA Astrophysics Data System (ADS)

Guenter, James K.; Tatum, Jim A.; Hawthorne, Robert A., III; Johnson, Ralph H.; Mathes, David T.; Hawkins, Bobby M.

2005-03-01

During a year of substantial consolidation in the VCSEL industry, Honeywell sold their VCSEL Optical Products Division, which has now officially changed its name to Advanced Optical Components (AOC). Both manufacture and applied research continue, however. Some of the developments of the past year are discussed in this paper. They include advances in the understanding of VCSEL degradation physics, substantial improvements in long-wavelength VCSEL performance, and continuing progress in manufacturing technology. In addition, higher speed serial communications products, at 10 gigabits and particularly at 4 gigabits per second, have shown faster than predicted growth. We place these technologies and AOC's approach to them in a market perspective, along with other emerging applications.

Optics for coherent X-ray applications.

PubMed

Yabashi, Makina; Tono, Kensuke; Mimura, Hidekazu; Matsuyama, Satoshi; Yamauchi, Kazuto; Tanaka, Takashi; Tanaka, Hitoshi; Tamasaku, Kenji; Ohashi, Haruhiko; Goto, Shunji; Ishikawa, Tetsuya

2014-09-01

Developments of X-ray optics for full utilization of diffraction-limited storage rings (DLSRs) are presented. The expected performance of DLSRs is introduced using the design parameters of SPring-8 II. To develop optical elements applicable to manipulation of coherent X-rays, advanced technologies on precise processing and metrology were invented. With propagation-based coherent X-rays at the 1 km beamline of SPring-8, a beryllium window fabricated with the physical-vapour-deposition method was found to have ideal speckle-free properties. The elastic emission machining method was utilized for developing reflective mirrors without distortion of the wavefronts. The method was further applied to production of diffraction-limited focusing mirrors generating the smallest spot size in the sub-10 nm regime. To enable production of ultra-intense nanobeams at DLSRs, a low-vibration cooling system for a high-heat-load monochromator and advanced diagnostic systems to characterize X-ray beam properties precisely were developed. Finally, new experimental schemes for combinative nano-analysis and spectroscopy realised with novel X-ray optics are discussed.

Dielectric Metasurface Optics: A New Platform for Compact Optical Sensing

NASA Astrophysics Data System (ADS)

Colburn, Shane

Metasurfaces, the 2D analogue of bulk metamaterials, show incredible promise for achieving nanoscale optical components that could support the growing infrastructure for the Internet of Things (IoT) and future sensing technologies. Consisting of quasiperiodic arrays of subwavelength scattering elements, metasurfaces apply spatial transfer functions to incident wavefronts, abruptly altering properties of light over a wavelength-scale thickness. By appropriately patterning scatterers on the structure, arbitrary functions can be implemented up to the limitations on the scattering properties of the particular elements. This thesis details theoretical work and simulations on the design of scattering elements with advanced capabilities for dielectric metasurfaces, showing polarization-multiplexed operation in the visible regime, multiwavelength capability in the visible regime along with a general methodology for eliminating chromatic aberrations at discrete wavelengths, and compact and tunable elements for 1550 nm operation inspired by an asymmetric Fabry-Perot cavity. These advancements enhance the capabilities of metasurfaces in the visible regime and help move toward the goal of achieving reconfigurable metasurfaces for compact and efficient optical sensors.

The Optical Society's 2016 topical meeting on optical interference coatings: introduction.

PubMed

Ristau, Detlev; Li, Li; Sargent, Robert; Sytchkova, Anna

2017-02-01

This feature issue of Applied Optics is dedicated to the 13th Topical Meeting on Optical Interference Coatings, which was held June 19-24, 2016, in Tucson, Arizona, USA. The conference, taking place every three years, is a focal point for global technical interchange in the field of optical interference coatings and provides premier opportunities for people working in the field to present their new advances in research and development. Papers presented at the meeting covered a broad range of topics, including fundamental research on coating design theory, new materials, and deposition and characterization technologies, as well as the vast and growing number of applications in electronic displays, communication, optical instruments, high power and ultra-fast lasers, solar cells, space missions, gravitational wave detection, and many others.

Proceedings 5th International Conference on Optics of Surfaces and Interfaces (OSI-V), Léon, México 26-30 May 2003: physica status solidi (c) - conferences and critical reviews

NASA Astrophysics Data System (ADS)

Mendoza, Bernardo S.

2003-05-01

physica status solidi (c) conferences and critical reviews publishes conference proceedings, ranging from large international meetings to specialized topical workshops as well as collections of topical reviews on various areas of current solid state physics research. The objective of "Optics of Surfaces and Interfaces" (OSI-V) is to bridge the gap between basic and applied science. Apart from recent advances in theoretical modeling and experimental research, special attention is given to novel techniques of optical spectroscopy at interfaces.

Wideband spectrum analysis of ultra-high frequency radio-wave signals due to advanced one-phonon non-collinear anomalous light scattering.

PubMed

Shcherbakov, Alexandre S; Arellanes, Adan Omar

2017-04-20

We present a principally new acousto-optical cell providing an advanced wideband spectrum analysis of ultra-high frequency radio-wave signals. For the first time, we apply a recently developed approach with the tilt angle to a one-phonon non-collinear anomalous light scattering. In contrast to earlier cases, now one can exploit a regime with the fixed optical wavelength for processing a great number of acoustic frequencies simultaneously in the linear regime. The chosen rutile-crystal combines a moderate acoustic velocity with low acoustic attenuation and allows us wide-band data processing within GHz-frequency acoustic waves. We have created and experimentally tested a 6-cm aperture rutile-made acousto-optical cell providing the central frequency 2.0 GHz, frequency bandwidth ∼0.52  GHz with the frequency resolution about 68.3 kHz, and ∼7620 resolvable spots. A similar cell permits designing an advanced ultra-high-frequency arm within a recently developed multi-band radio-wave acousto-optical spectrometer for astrophysical studies. This spectrometer is intended to operate with a few parallel optical arms for processing the multi-frequency data flows within astrophysical observations. Keeping all the instrument's advantages of the previous schematic arrangement, now one can create the highest-frequency arm using the developed rutile-based acousto-optical cell. It permits optimizing the performances inherent in that arm via regulation of both the central frequency and the frequency bandwidth for spectrum analysis.

Autonomous Deep-Space Optical Navigation Project

NASA Technical Reports Server (NTRS)

D'Souza, Christopher

2014-01-01

This project will advance the Autonomous Deep-space navigation capability applied to Autonomous Rendezvous and Docking (AR&D) Guidance, Navigation and Control (GNC) system by testing it on hardware, particularly in a flight processor, with a goal of limited testing in the Integrated Power, Avionics and Software (IPAS) with the ARCM (Asteroid Retrieval Crewed Mission) DRO (Distant Retrograde Orbit) Autonomous Rendezvous and Docking (AR&D) scenario. The technology, which will be harnessed, is called 'optical flow', also known as 'visual odometry'. It is being matured in the automotive and SLAM (Simultaneous Localization and Mapping) applications but has yet to be applied to spacecraft navigation. In light of the tremendous potential of this technique, we believe that NASA needs to design a optical navigation architecture that will use this technique. It is flexible enough to be applicable to navigating around planetary bodies, such as asteroids.

Investigation of Zerodur material processing

NASA Technical Reports Server (NTRS)

Johnson, R. Barry

1993-01-01

The Final Report of the Center for Applied Optics (CAO), of The University of Alabama (UAH) study entitled 'Investigation of Zerodur Material Processing' is presented. The objectives of the effort were to prepare glass samples by cutting, grinding, etching, and polishing block Zerodur to desired specifications using equipment located in the optical shop located in the Optical System Branch at NASA/MSFC; characterize samples for subsurface damage and surface roughness; utilize Zerodur samples for coating investigations; and perform investigations into enhanced optical fabrication and metrology techniques. The results of this investigation will be used to support the Advanced X Ray Astrophysics Facility (AXAF) program as well as other NASA/MSFC research programs. The results of the technical effort are presented and discussed.

Advances in Laryngoscopy.

PubMed

Aziz, Michael

2015-01-01

Recent technological advances have made airway management safer. Because difficult intubation remains challenging to predict, having tools readily available that can be used to manage a difficult airway in any setting is critical. Fortunately, video technology has resulted in improvements for intubation performance while using laryngoscopy by various means. These technologies have been applied to rigid optical stylets, flexible intubation scopes, and, most notably, rigid laryngoscopes. These tools have proven effective for the anticipated difficult airway as well as the unanticipated difficult airway.

Photoluminescence analysis of self induced planer alignment in azo dye dispersed nematic liquid crystal complex

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kumar, Rishi, E-mail: kkraina@gmail.com; Sood, Srishti, E-mail: kkraina@gmail.com; Raina, K. K., E-mail: kkraina@gmail.com

2014-04-24

We have developed azo dye doped nematic liquid crystal complex for advanced photonic liquid crystal display technology aspects. Disperse orange azo dye self introduced planer alignment in the nematic liquid crystal without any surface anchoring treatment. Planer alignment was characterized by optical polarizing microscopy. The electro-optical switching response of dye disperse planer aligned nematic cell was investigated as a function of applied voltage with the help of photoluminescence spectrophotometer for the tuning of photoluminescence contrast.

Multifocus microscopy with precise color multi-phase diffractive optics applied in functional neuronal imaging.

PubMed

Abrahamsson, Sara; Ilic, Rob; Wisniewski, Jan; Mehl, Brian; Yu, Liya; Chen, Lei; Davanco, Marcelo; Oudjedi, Laura; Fiche, Jean-Bernard; Hajj, Bassam; Jin, Xin; Pulupa, Joan; Cho, Christine; Mir, Mustafa; El Beheiry, Mohamed; Darzacq, Xavier; Nollmann, Marcelo; Dahan, Maxime; Wu, Carl; Lionnet, Timothée; Liddle, J Alexander; Bargmann, Cornelia I

2016-03-01

Multifocus microscopy (MFM) allows high-resolution instantaneous three-dimensional (3D) imaging and has been applied to study biological specimens ranging from single molecules inside cells nuclei to entire embryos. We here describe pattern designs and nanofabrication methods for diffractive optics that optimize the light-efficiency of the central optical component of MFM: the diffractive multifocus grating (MFG). We also implement a "precise color" MFM layout with MFGs tailored to individual fluorophores in separate optical arms. The reported advancements enable faster and brighter volumetric time-lapse imaging of biological samples. In live microscopy applications, photon budget is a critical parameter and light-efficiency must be optimized to obtain the fastest possible frame rate while minimizing photodamage. We provide comprehensive descriptions and code for designing diffractive optical devices, and a detailed methods description for nanofabrication of devices. Theoretical efficiencies of reported designs is ≈90% and we have obtained efficiencies of > 80% in MFGs of our own manufacture. We demonstrate the performance of a multi-phase MFG in 3D functional neuronal imaging in living C. elegans.

Application of telecom planar lightwave circuits for homeland security sensing

NASA Astrophysics Data System (ADS)

Veldhuis, Gert J.; Elders, Job; van Weerden, Harm; Amersfoort, Martin

2004-03-01

Over the past decade, a massive effort has been made in the development of planar lightwave circuits (PLCs) for application in optical telecommunications. Major advances have been made, on both the technological and functional performance front. Highly sophisticated software tools that are used to tailor designs to required functional performance support these developments. In addition extensive know-how in the field of packaging, testing, and failure mode and effects analysis (FMEA) has been built up in the struggle for meeting the stringent Telcordia requirements that apply to telecom products. As an example, silica-on-silicon is now a mature technology available at several industrial foundries around the world, where, on the performance front, the arrayed-waveguide grating (AWG) has evolved into an off-the-shelf product. The field of optical chemical-biological (CB) sensors for homeland security application can greatly benefit from the advances as described above. In this paper we discuss the currently available technologies, device concepts, and modeling tools that have emerged from the telecommunications arena and that can effectively be applied to the field of homeland security. Using this profound telecom knowledge base, standard telecom components can readily be tailored for detecting CB agents. Designs for telecom components aim at complete isolation from the environment to exclude impact of environmental parameters on optical performance. For sensing applications, the optical path must be exposed to the measurand, in this area additional development is required beyond what has already been achieved in telecom development. We have tackled this problem, and are now in a position to apply standard telecom components for CB sensing. As an example, the application of an AWG as a refractometer is demonstrated, and its performance evaluated.

The reform of the teaching mode of Applied Optics curriculum and analysis of teaching effect

NASA Astrophysics Data System (ADS)

Ning, Yu; Xu, Zhongjie; Li, Dun; Chen, Zilun; Cheng, Xiangai; Zhong, Hairong

2017-08-01

Military academies have two distinctive characteristics on talent training: Firstly, we must teach facing actual combat and connecting with academic frontier. Secondly, the bachelor's degree education and the military education should be balanced. The teaching mode of basic curriculum in military academies must be reformed and optimized on the basis of the traditional teaching mode, so as to ensure the high quality of teaching and provide enough guidance and help for students to support their academic burden. In this paper, our main work on "Applied Optics" teaching mode reform is introduced: First of all, we research extensively and learn fully from advanced teaching modes of the well-known universities at home and abroad, a whole design is made for the teaching mode of the core curriculum of optical engineering in our school "Applied Optics", building a new teaching mode which takes the methods of teaching basic parts as details, teaching application parts as emphases, teaching frontier parts as topics and teaching actual combat parts on site. Then combining with the questionnaire survey of students and opinions proposed by relevant experts in the teaching seminar, teaching effect and generalizability of the new teaching mode are analyzed and evaluated.

APPLIED OPTICS. Overcoming Kerr-induced capacity limit in optical fiber transmission.

PubMed

Temprana, E; Myslivets, E; Kuo, B P-P; Liu, L; Ataie, V; Alic, N; Radic, S

2015-06-26

Nonlinear optical response of silica imposes a fundamental limit on the information transfer capacity in optical fibers. Communication beyond this limit requires higher signal power and suppression of nonlinear distortions to prevent irreversible information loss. The nonlinear interaction in silica is a deterministic phenomenon that can, in principle, be completely reversed. However, attempts to remove the effects of nonlinear propagation have led to only modest improvements, and the precise physical mechanism preventing nonlinear cancellation remains unknown. We demonstrate that optical carrier stability plays a critical role in canceling Kerr-induced distortions and that nonlinear wave interaction in silica can be substantially reverted if optical carriers possess a sufficient degree of mutual coherence. These measurements indicate that fiber information capacity can be notably increased over previous estimates. Copyright © 2015, American Association for the Advancement of Science.

Optical fiber evanescent absorption sensors for high-temperature gas sensing in advanced coal-fired power plants

NASA Astrophysics Data System (ADS)

Buric, Michael P.; Ohodnicky, Paul R.; Duy, Janice

2012-10-01

Modern advanced energy systems such as coal-fired power plants, gasifiers, or similar infrastructure present some of the most challenging harsh environments for sensors. The power industry would benefit from new, ultra-high temperature devices capable of surviving in hot and corrosive environments for embedded sensing at the highest value locations. For these applications, we are currently exploring optical fiber evanescent wave absorption spectroscopy (EWAS) based sensors consisting of high temperature core materials integrated with novel high temperature gas sensitive cladding materials. Mathematical simulations can be used to assist in sensor development efforts, and we describe a simulation code that assumes a single thick cladding layer with gas sensitive optical constants. Recent work has demonstrated that Au nanoparticle-incorporated metal oxides show a potentially useful response for high temperature optical gas sensing applications through the sensitivity of the localized surface plasmon resonance absorption peak to ambient atmospheric conditions. Hence, the simulation code has been applied to understand how such a response can be exploited in an optical fiber based EWAS sensor configuration. We demonstrate that interrogation can be used to optimize the sensing response in such materials.

Hierarchy curriculum for practical skills training in optics and photonics

NASA Astrophysics Data System (ADS)

Zheng, XiaoDong; Wang, XiaoPing; Liu, Xu; Liu, XiangDong; Lin, YuanFang

2017-08-01

The employers in optical engineering fields hope to recruit students who are capable of applying optical principles to solve engineering problems and have strong laboratory skills. In Zhejiang University, a hierarchy curriculum for practical skill training has been constructed to satisfy this demand. This curriculum includes "Introductive practicum" for freshmen, "Opto-mechanical systems design", "Engineering training", "Electronic system design", "Student research training program (SRTP)", "National University Students' Optical-Science-Technology Competition game", and "Offcampus externship". Without cutting optical theory credit hours, this hierarchy curriculum provides a step-by-step solution to enhance students' practical skills. By following such a hierarchy curriculum, students can smoothly advance from a novice to a qualified professional expert in optics. They will be able to utilize optical engineering tools to design, build, analyze, improve, and test systems, and will be able to work effectively in teams to solve problems in engineering and design.

Teaching lens, optical systems, and opto-mechanical systems design at the Irvine Center for Applied Competitive Technologies (CACT)

NASA Astrophysics Data System (ADS)

Doushkina, Valentina V.; Silberman, Donn M.

2007-09-01

For well over a decade, the Laser Electro-Optics Technology (LET) program has been teaching introductory laser and optics classes at Irvine Valley College (IVC). At the beginning of the telecom boom, the Irvine CACT was established to teach optics fabrication to support the many optics fabrication businesses in Southern California. In the past few years, these two programs have merged - with some help from the Optics Institute of Southern California (OISC) - and grown under the newly established Advanced Technology and Education Park (ATEP). IVC and ATEP are both operated by the South Orange County Community College District (SOCCCD). This year a new program of three courses was established to teach, in sequence, lens, optical systems and optomechanical systems design. This paper reviews the reasons for establishing these courses and their content, the students' motivations for taking them and their employers' incentives for encouraging the students.

Optics for coherent X-ray applications

PubMed Central

Yabashi, Makina; Tono, Kensuke; Mimura, Hidekazu; Matsuyama, Satoshi; Yamauchi, Kazuto; Tanaka, Takashi; Tanaka, Hitoshi; Tamasaku, Kenji; Ohashi, Haruhiko; Goto, Shunji; Ishikawa, Tetsuya

2014-01-01

Developments of X-ray optics for full utilization of diffraction-limited storage rings (DLSRs) are presented. The expected performance of DLSRs is introduced using the design parameters of SPring-8 II. To develop optical elements applicable to manipulation of coherent X-rays, advanced technologies on precise processing and metrology were invented. With propagation-based coherent X-rays at the 1 km beamline of SPring-8, a beryllium window fabricated with the physical-vapour-deposition method was found to have ideal speckle-free properties. The elastic emission machining method was utilized for developing reflective mirrors without distortion of the wavefronts. The method was further applied to production of diffraction-limited focusing mirrors generating the smallest spot size in the sub-10 nm regime. To enable production of ultra-intense nanobeams at DLSRs, a low-vibration cooling system for a high-heat-load monochromator and advanced diagnostic systems to characterize X-ray beam properties precisely were developed. Finally, new experimental schemes for combinative nano-analysis and spectroscopy realised with novel X-ray optics are discussed. PMID:25177986

Microfabricated X-Ray Optics Technology Development for the Constellation-X Mission

NASA Technical Reports Server (NTRS)

Schattenburg, Mark L.

2003-01-01

During the period of this Cooperative Agreement, MIT developed advanced methods for applying silicon micro-stuctures for the precision assembly of foil x-ray optics in support of the Constellution-X Spectroscopy X-ray Telescope (SXT) development effort at Goddard Space Flight Center (GSFC). MIT developed improved methods for fabricating and characterizing the precision silicon micro-combs. MIT also developed and characterized assembly tools and several types of metrology tools in order to characterize and reduce the errors associated with precision assembly of foil optics. Results of this effort were published and presented to the scientific community and the GSFC SXT team.

Space Science

NASA Image and Video Library

1998-08-31

NASA's Space Optics Manufacturing Center has been working to expand our view of the universe via sophisticated new telescopes. The Optics Center's goal is to develop low-cost, advanced space optics technologies for the NASA program in the 21st century - including the long-term goal of imaging Earth-like planets in distant solar systems. To reduce the cost of mirror fabrication, Marshall Space Flight Center (MSFC) has developed replication techniques, the machinery and materials to replicate electro-formed nickel mirrors. The process allows fabricating precisely shaped mandrels to be used and reused as masters for replicating high-quality mirrors. This image shows a lightweight replicated x-ray mirror with gold coatings applied.

Screen-Cage Ion Plating Of Silver On Polycrystalline Alumina

NASA Technical Reports Server (NTRS)

Spalvins, Talivaldis; Sliney, Harold E.; Deadmore, Daniel L.

1995-01-01

Screen-cage ion plating (SCIP) cost-effective technique offering high throwing power for deposition of adherent metal films on ceramic substrates. Applies silver films to complexly shaped substrates of polycrystalline alumina. Silver adheres tenaciously and reduces friction. SCIP holds promise for applying lubricating soft metallic films to high-temperature ceramic components of advanced combustion engines. Other potential uses include coating substrates with metal for protection against corrosion, depositing electrical conductors on dielectric substrates, making optically reflective or electrically or thermally conductive surface layers, and applying decorative metal coats to ceramic trophies or sculptures.

Space Science

NASA Image and Video Library

1999-04-01

NASA's Space Optics Manufacturing Center has been working to expand our view of the universe via sophisticated new telescopes. The Optics Center's goal is to develop low-cost, advanced space optics technologies for the NASA program in the 21st century - including the long-term goal of imaging Earth-like planets in distant solar systems. To reduce the cost of mirror fabrication, Marshall Space Flight Center (MSFC) has developed replication techniques, the machinery, and materials to replicate electro-formed nickel mirrors. The process allows fabricating precisely shaped mandrels to be used and reused as masters for replicating high-quality mirrors. Image shows Dr. Alan Shapiro cleaning mirror mandrel to be applied with highly reflective and high-density coating in the Large Aperture Coating Chamber, MFSC Space Optics Manufacturing Technology Center (SOMTC).

[The application of inductively coupled plasma atomic emission spectrometry/mass spectrometry to the analysis of advanced ceramic materials].

PubMed

Wang, Zheng; Wang, Shi-Wei; Qiu, De-Ren; Yang, Peng-Yuan

2009-10-01

Advanced ceramics have been applied to various important fields such as information science, aeronautics and astronautics, and life sciences. However, the optics and electric properties of ceramics are significantly affected by the micro and trace impurities existing in the material even at very low concentration level. Thus, the accurate determination of impurities is important for materials preparation and performance. Methodology of the analysis of advanced ceramic materials using ICP-AES/MS was reviewed in the present paper for the past decade. Various techniques of sample introduction, especially advances in the authors' recent work, are described in detail. The developing trend is also presented. Sixty references are cited.

Use of 3000 Bragg Grating Strain Sensors Distributed on Four Eight-meter Optical Fibers During Static Load Tests of a Composite Structure

NASA Technical Reports Server (NTRS)

Childers, Brooks A.; Froggatt, Mark E.; Allison, Sidney G.; Moore, Thomas C., Sr.; Hare, David A.; Batten, Christopher F.; Jegley, Dawn C.

2001-01-01

This paper describes the use of a fiber optic system to measure strain at thousands of locations along optical fibers where weakly reflecting Bragg gratings have been photoetched. The optical fibers were applied to an advanced composite transport wing along with conventional foil strain gages. A comparison of the fiber optic and foil gage systems used for this test will be presented including: a brief description of both strain data systems; a discussion of the process used for installation of the optical fiber; comparative data from the composite wing test; the processes used for the location and display of the high density fiber optic data. Calibration data demonstrating the potential accuracy of the fiber optic system will also be presented. The opportunities for industrial and commercial applications will be discussed. The fiber optic technique is shown to be a valuable augmentation to foil strain gages providing insight to structural behavior previously requiring reliance on modeling.

Global Coordinates and Exact Aberration Calculations Applied to Physical Optics Modeling of Complex Optical Systems

NASA Astrophysics Data System (ADS)

Lawrence, G.; Barnard, C.; Viswanathan, V.

1986-11-01

Historically, wave optics computer codes have been paraxial in nature. Folded systems could be modeled by "unfolding" the optical system. Calculation of optical aberrations is, in general, left for the analyst to do with off-line codes. While such paraxial codes were adequate for the simpler systems being studied 10 years ago, current problems such as phased arrays, ring resonators, coupled resonators, and grazing incidence optics require a major advance in analytical capability. This paper describes extension of the physical optics codes GLAD and GLAD V to include a global coordinate system and exact ray aberration calculations. The global coordinate system allows components to be positioned and rotated arbitrarily. Exact aberrations are calculated for components in aligned or misaligned configurations by using ray tracing to compute optical path differences and diffraction propagation. Optical path lengths between components and beam rotations in complex mirror systems are calculated accurately so that coherent interactions in phased arrays and coupled devices may be treated correctly.

Future of bone pathology, bone grafting, and osseointegration in oral and maxillofacial surgery: how applying optical advancements can help both fields

NASA Astrophysics Data System (ADS)

Tandon, Rahul; Herford, Alan S.

2013-03-01

Introduction: In recent years, advances in technology are propelling the field of oral and maxillofacial surgery into new realms. With a relatively thin alveolar mucosa overlying the underlying bone, significant diagnostic and therapeutic advantages are present. However, there remains an enormous gap between advancements in physics, in particular optics, and oral and maxillofacial surgery. Bone Pathology: Improvements in diagnosis, classification, and treatment of the various bone pathologies are still being sought after as advancements in technology continue to progress. Combining the clinical, histological, and pathological characteristics with these advancements, patients with debilitating pathologies may have more promising treatment options and prognosis. Bone Grafting: Defects in the facial bones, in particular the jaws, may be due to a number of reasons: pathology, trauma, infections, congenital deformities, or simply due to atrophy. Bone grafting is commonly employed to correct such defects, and allows new bone formation through tissue regeneration. Osseointegration: Growing use of dental implants has focused attention on osseointegration and its process. Osseointegration refers to the actual process of the direct contact between bone and implant, without an intervening soft tissue layer. The theories proposed regarding this process are many, yet there lacks a clear, unified stance on the actual process and its mechanisms. Further investigation using optical probes could provide that unifying answer. Conclusion: The primary goal of this lecture is to introduce pioneers in the field of optics to the field of oral and maxillofacial surgery. With a brief introduction into the procedures and techniques, we are hopeful to bridge the ever-widening gap between the clinical science and the basic sciences.

Compensating Atmospheric Turbulence Effects at High Zenith Angles with Adaptive Optics Using Advanced Phase Reconstructors

NASA Astrophysics Data System (ADS)

Roggemann, M.; Soehnel, G.; Archer, G.

Atmospheric turbulence degrades the resolution of images of space objects far beyond that predicted by diffraction alone. Adaptive optics telescopes have been widely used for compensating these effects, but as users seek to extend the envelopes of operation of adaptive optics telescopes to more demanding conditions, such as daylight operation, and operation at low elevation angles, the level of compensation provided will degrade. We have been investigating the use of advanced wave front reconstructors and post detection image reconstruction to overcome the effects of turbulence on imaging systems in these more demanding scenarios. In this paper we show results comparing the optical performance of the exponential reconstructor, the least squares reconstructor, and two versions of a reconstructor based on the stochastic parallel gradient descent algorithm in a closed loop adaptive optics system using a conventional continuous facesheet deformable mirror and a Hartmann sensor. The performance of these reconstructors has been evaluated under a range of source visual magnitudes and zenith angles ranging up to 70 degrees. We have also simulated satellite images, and applied speckle imaging, multi-frame blind deconvolution algorithms, and deconvolution algorithms that presume the average point spread function is known to compute object estimates. Our work thus far indicates that the combination of adaptive optics and post detection image processing will extend the useful envelope of the current generation of adaptive optics telescopes.

An Attenuated Total Reflectance Sensor for Copper: An Experiment for Analytical or Physical Chemistry

ERIC Educational Resources Information Center

Shtoyko, Tanya; Zudans, Imants; Seliskar, Carl J.; Heineman, William R.; Richardson, John N.

2004-01-01

A sensor experiment which can be applied to advanced undergraduate laboratory course in physical or analytical chemistry is described along with certain concepts like the demonstration of chemical sensing, preparation of thin films on a substrate, microtitration, optical determination of complex ion stoichiometry and isosbestic point. It is seen…

Applied optics. Multiwavelength achromatic metasurfaces by dispersive phase compensation.

PubMed

Aieta, Francesco; Kats, Mikhail A; Genevet, Patrice; Capasso, Federico

2015-03-20

The replacement of bulk refractive optical elements with diffractive planar components enables the miniaturization of optical systems. However, diffractive optics suffers from large chromatic aberrations due to the dispersion of the phase accumulated by light during propagation. We show that this limitation can be overcome with an engineered wavelength-dependent phase shift imparted by a metasurface, and we demonstrate a design that deflects three wavelengths by the same angle. A planar lens without chromatic aberrations at three wavelengths is also presented. Our designs are based on low-loss dielectric resonators, which introduce a dense spectrum of optical modes to enable dispersive phase compensation. The suppression of chromatic aberrations in metasurface-based planar photonics will find applications in lightweight collimators for displays, as well as chromatically corrected imaging systems. Copyright © 2015, American Association for the Advancement of Science.

76 FR 12144 - Advanced Optics Electronics, Inc.; Order of Suspension of Trading

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-04

... SECURITIES AND EXCHANGE COMMISSION [File No. 500-1] Advanced Optics Electronics, Inc.; Order of... lack of current and accurate information concerning the securities of Advanced Optics Electronics, Inc... in Advanced Optics Electronics, Inc. Therefore, it is ordered, pursuant to Section 12(k) of the...

Efficient 'Optical Furnace': A Cheaper Way to Make Solar Cells is Reaching the Marketplace

DOE Office of Scientific and Technical Information (OSTI.GOV)

von Kuegelgen, T.

In Bhushan Sopori's laboratory, you'll find a series of optical furnaces he has developed for fabricating solar cells. When not in use, they sit there discreetly among the lab equipment. But when a solar silicon wafer is placed inside one for processing, Sopori walks over to a computer and types in a temperature profile. Almost immediately this fires up the furnace, which glows inside and selectively heats up the silicon wafer to 800 degrees centigrade by the intense light it produces. Sopori, a principal engineer at the National Renewable Energy Laboratory, has been researching and developing optical furnace technology formore » around 20 years. He says it's a challenging technology to develop because there are many issues to consider when you process a solar cell, especially in optics. Despite the challenges, Sopori and his research team have advanced the technology to the point where it will benefit all solar cell manufacturers. They are now developing a commercial version of the furnace in partnership with a manufacturer. 'This advanced optical furnace is highly energy efficient, and it can be used to manufacture any type of solar cell,' he says. Each type of solar cell or manufacturing process typically requires a different furnace configuration and temperature profile. With NREL's new optical furnace system, a solar cell manufacturer can ask the computer for any temperature profile needed for processing a solar cell, and the same type of furnace is suitable for several solar cell fabrication process steps. 'In the future, solar cell manufacturers will only need this one optical furnace because it can be used for any process, including diffusion, metallization and oxidation,' Sopori says. 'This helps reduce manufacturing costs.' One startup company, Applied Optical Systems, has recognized the furnace's potential for manufacturing thin-film silicon cells. 'We'd like to develop thin-film silicon cells with higher efficiencies, up to 15 to 18 percent, and we believe this furnace will enable us to do so,' says A. Rangappan, founder and CEO of Applied Optical Systems. Rangappan also says it will take only a few minutes for the optical furnace to process a thin-film solar cell, which reduces manufacturing costs. Overall, he estimates the company's solar cell will cost around 80 cents per watt. For manufacturing these thin-film silicon cells, Applied Optical Systems and NREL have developed a partnership through a cooperative research and development agreement (CRADA) to construct an optical furnace system prototype. DOE is providing $500,000 from its Technology Commercialization Development Fund to help offset the prototype's development costs because of the technology's significant market potential. The program has provided the NREL technology transfer office with a total of $4 million to expand such collaborative efforts between NREL researchers and companies. Applied Optical will construct a small version of the optical furnace based on the prototype design in NREL's process development and integration laboratory through a separate CRADA. This small furnace will only develop one solar cell wafer at a time. Then, the company will construct a large, commercial-scale optical furnace at its own facilities, which will turn out around 1,000 solar cell wafers per hour. 'We hope to start using the optical furnace for manufacturing within four to five years,' Rangappan says. Meanwhile, another partnership using the optical furnace has evolved between NREL and SiXtron Advanced Materials, another startup. Together they'll use the optical furnace to optimize the metallization process for novel antireflective solar cell coatings. The process is not only expected to yield higher efficiencies for silicon-based solar cells, but also lowers processing costs and eliminates safety concerns for manufacturers. Most solar cell manufacturers currently use a plasma-enhanced chemical vapor deposition (PECVD) system with compressed and extremely pyrophoric silane gas (SiH4) for applying passivation antireflective coatings (ARC). If silane is exposed to air, the SiH4 will explode - a serious safety issue for high-volume manufacturers. SiXtron's process uses a solid, silicon-based polymer that's converted into noncompressed, nonexplosive gas, which then flows to a standard PECVD system. 'The solid source is so safe to handle that it can be shipped by FedEx,' says Zbigniew Barwicz, president and CEO of SiXtron. Barwicz says manufacturers can use the same PECVD processing equipment for the SiXtron process that they already use for SiH4, a plug-and-play solution. For this novel passivation ARC process, NREL is helping to optimize the metallization parameters. NREL has developed a new technology called optical processing. One of the applications of this process is fire-through contact formation of silicon solar cells.« less

Rectangular QPSK for generation of optical eight-ary phase-shift keying.

PubMed

Lu, Guo-Wei; Sakamoto, Takahide; Kawanishi, Tetsuya

2011-09-12

Quadrature phase-shift keying (QPSK) is usually generated using an in-phase/quadrature (IQ) modulator in a balanced driving-condition, showing a square-shape constellation in complex plane. This conventional QPSK is referred to as square QPSK (S-QPSK) in this paper. On the other hand, when an IQ modulator is driven in an un-balanced manner with different amplitudes in in-phase (I) and quadrature (Q) branches, a rectangular QPSK (R-QPSK) could be synthesized. The concept of R-QPSK is proposed for the first time and applied to optical eight-ary phase-shift keying (8PSK) transmitter. By cascading an S-QPSK and an R-QPSK, an optical 8PSK could be synthesized. The transmitter configuration is based on two cascaded IQ modulators, which also could be used to generate other advanced multi-level formats like quadrature amplitude modulation (QAM) when different driving and bias conditions are applied. Therefore, the proposed transmitter structure has potential to be deployed as a versatile transmitter for synthesis of several different multi-level modulation formats for the future dynamic optical networks. A 30-Gb/s optical 8PSK is experimentally demonstrated using the proposed solution.

Mechanical design of thin-film diamond crystal mounting apparatus for coherence preservation hard x-ray optics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shu, Deming, E-mail: shu@aps.anl.gov; Shvyd’ko, Yuri V.; Stoupin, Stanislav

2016-07-27

A new thin-film diamond crystal mounting apparatus has been designed at the Advanced Photon Source (APS) for coherence preservation hard x-ray optics with optimized thermal contact and minimized crystal strain. This novel mechanical design can be applied to new development in the field of: x-ray optics cavities for hard x-ray free-electron laser oscillators (XFELOs), self-seeding monochromators for hard x-ray free-electron laser (XFEL) with high average thermal loading, high heat load diamond crystal monochromators and beam-sharing/beam-split-and-delay devices for XFEL facilities and future upgraded high-brightness coherent x-ray source in the MBA lattice configuration at the APS.

Advances in the production of freeform optical surfaces

NASA Astrophysics Data System (ADS)

Tohme, Yazid E.; Luniya, Suneet S.

2007-05-01

Recent market demands for free-form optics have challenged the industry to find new methods and techniques to manufacture free-form optical surfaces with a high level of accuracy and reliability. Production techniques are becoming a mix of multi-axis single point diamond machining centers or deterministic ultra precision grinding centers coupled with capable measurement systems to accomplish the task. It has been determined that a complex software tool is required to seamlessly integrate all aspects of the manufacturing process chain. Advances in computational power and improved performance of computer controlled precision machinery have driven the use of such software programs to measure, visualize, analyze, produce and re-validate the 3D free-form design thus making the process of manufacturing such complex surfaces a viable task. Consolidation of the entire production cycle in a comprehensive software tool that can interact with all systems in design, production and measurement phase will enable manufacturers to solve these complex challenges providing improved product quality, simplified processes, and enhanced performance. The work being presented describes the latest advancements in developing such software package for the entire fabrication process chain for aspheric and free-form shapes. It applies a rational B-spline based kernel to transform an optical design in the form of parametrical definition (optical equation), standard CAD format, or a cloud of points to a central format that drives the simulation. This software tool creates a closed loop for the fabrication process chain. It integrates surface analysis and compensation, tool path generation, and measurement analysis in one package.

Optical trapping of nanoparticles by ultrashort laser pulses.

PubMed

Usman, Anwar; Chiang, Wei-Yi; Masuhara, Hiroshi

2013-01-01

Optical trapping with continuous-wave lasers has been a fascinating field in the optical manipulation. It has become a powerful tool for manipulating micrometer-sized objects, and has been widely applied in physics, chemistry, biology, material, and colloidal science. Replacing the continuous-wave- with pulsed-mode laser in optical trapping has already revealed some novel phenomena, including the stable trap, modifiable trapping positions, and controllable directional optical ejections of particles in nanometer scales. Due to two distinctive features; impulsive peak powers and relaxation time between consecutive pulses, the optical trapping with the laser pulses has been demonstrated to have some advantages over conventional continuous-wave lasers, particularly when the particles are within Rayleigh approximation. This would open unprecedented opportunities in both fundamental science and application. This Review summarizes recent advances in the optical trapping with laser pulses and discusses the electromagnetic formulations and physical interpretations of the new phenomena. Its aim is rather to show how beautiful and promising this field will be, and to encourage the in-depth study of this field.

Adaptive optics retinal imaging: emerging clinical applications.

PubMed

Godara, Pooja; Dubis, Adam M; Roorda, Austin; Duncan, Jacque L; Carroll, Joseph

2010-12-01

The human retina is a uniquely accessible tissue. Tools like scanning laser ophthalmoscopy and spectral domain-optical coherence tomography provide clinicians with remarkably clear pictures of the living retina. Although the anterior optics of the eye permit such non-invasive visualization of the retina and associated pathology, the same optics induce significant aberrations that obviate cellular-resolution imaging in most cases. Adaptive optics (AO) imaging systems use active optical elements to compensate for aberrations in the optical path between the object and the camera. When applied to the human eye, AO allows direct visualization of individual rod and cone photoreceptor cells, retinal pigment epithelium cells, and white blood cells. AO imaging has changed the way vision scientists and ophthalmologists see the retina, helping to clarify our understanding of retinal structure, function, and the etiology of various retinal pathologies. Here, we review some of the advances that were made possible with AO imaging of the human retina and discuss applications and future prospects for clinical imaging.

Application of biomimetics in x-ray optics

NASA Astrophysics Data System (ADS)

Hudec, R.; Remisova, K.

2017-05-01

The principles of biomimetics were successfully applied in X ray optics in the past and recently, e.g. in Lobster-Eye optical systems. However, the recent growing knowledge of sea vision, especially of peculiar mirror eyes of scallops, crustaceans, and deep sea fishes, makes it possible to consider other such applications. One of the most important discoveries is finding of mirror eyes in deep sea fish Dolichopteryx longipes based on large large numbers of very small mirror plates organized in specific positions. This arrangement may even include principles of active optics. We report on ongoing study with focus on understanding of very specific mirror eyes of sea animals and how they may help us to design and develop special optics for scientific applications. We study the ways these mirror eyes work, what are the advantages of these peculiar eye arrangements, and whether these optics can be used in advanced devices, e. g. X-ray optics. We will briefly present and discuss the preliminary results.

Advanced Interrogation of Fiber-Optic Bragg Grating and Fabry-Perot Sensors with KLT Analysis

PubMed Central

Tosi, Daniele

2015-01-01

The Karhunen-Loeve Transform (KLT) is applied to accurate detection of optical fiber sensors in the spectral domain. By processing an optical spectrum, although coarsely sampled, through the KLT, and subsequently processing the obtained eigenvalues, it is possible to decode a plurality of optical sensor results. The KLT returns higher accuracy than other demodulation techniques, despite coarse sampling, and exhibits higher resilience to noise. Three case studies of KLT-based processing are presented, representing most of the current challenges in optical fiber sensing: (1) demodulation of individual sensors, such as Fiber Bragg Gratings (FBGs) and Fabry-Perot Interferometers (FPIs); (2) demodulation of dual (FBG/FPI) sensors; (3) application of reverse KLT to isolate different sensors operating on the same spectrum. A simulative outline is provided to demonstrate the KLT operation and estimate performance; a brief experimental section is also provided to validate accurate FBG and FPI decoding. PMID:26528975

Advanced Interrogation of Fiber-Optic Bragg Grating and Fabry-Perot Sensors with KLT Analysis.

PubMed

Tosi, Daniele

2015-10-29

The Karhunen-Loeve Transform (KLT) is applied to accurate detection of optical fiber sensors in the spectral domain. By processing an optical spectrum, although coarsely sampled, through the KLT, and subsequently processing the obtained eigenvalues, it is possible to decode a plurality of optical sensor results. The KLT returns higher accuracy than other demodulation techniques, despite coarse sampling, and exhibits higher resilience to noise. Three case studies of KLT-based processing are presented, representing most of the current challenges in optical fiber sensing: (1) demodulation of individual sensors, such as Fiber Bragg Gratings (FBGs) and Fabry-Perot Interferometers (FPIs); (2) demodulation of dual (FBG/FPI) sensors; (3) application of reverse KLT to isolate different sensors operating on the same spectrum. A simulative outline is provided to demonstrate the KLT operation and estimate performance; a brief experimental section is also provided to validate accurate FBG and FPI decoding.

Aimulet: a multilingual spatial optical voice card terminal for location and direction based information services

NASA Astrophysics Data System (ADS)

Itoh, Hideo; Lin, Xin; Kaji, Ryosaku; Niwa, Tatsuya; Nakamura, Yoshiyuki; Nishimura, Takuichi

2006-01-01

The National Institute of Advanced Industrial Science and Technology (AIST) in Japan has been developing Aimulet, which is a compact low-power consuming information terminal for a personal information services. Conventional Aimulet, which is called Aimulet ver. 1 or CoBIT, has features of location and direction sensitive information service device without batteries. On the other hand, the Aimulet ver. 1 has two subjects, one is multiplex and demultiplex of some contents, and another is operation under sunshine. In Former subject is of solved by the wavelength multiplex technique using LED emitter with different wavelength and dielectric optical filters. Latter subject is solved by new micro spherical solar cells with a visible-light-eliminating optical filter and a new design of light irradiation. These techniques are applied to the EXPO 2005, Aichi Japan and introduced in public. The former technique is applied on Aimulet GH, which is used in Orange Hall of the Global House, scientific museum with a fossil of a frozen mammoth. The latter technique is applied on Aimulet LA, which is used in the Laurie Anderson's WALK project in the Japanese Garden.

Femtosecond all-optical synchronization of an X-ray free-electron laser

DOE PAGES

Schulz, S.; Grguraš, I.; Behrens, C.; ...

2015-01-20

Many advanced applications of X-ray free-electron lasers require pulse durations and time resolutions of only a few femtoseconds. To generate these pulses and to apply them in time-resolved experiments, synchronization techniques that can simultaneously lock all independent components, including all accelerator modules and all external optical lasers, to better than the delivered free-electron laser pulse duration, are needed. Here we achieve all-optical synchronization at the soft X-ray free-electron laser FLASH and demonstrate facility-wide timing to better than 30 fs r.m.s. for 90 fs X-ray photon pulses. Crucially, our analysis indicates that the performance of this optical synchronization is limited primarilymore » by the free-electron laser pulse duration, and should naturally scale to the sub-10 femtosecond level with shorter X-ray pulses.« less

Femtosecond all-optical synchronization of an X-ray free-electron laser

PubMed Central

Schulz, S.; Grguraš, I.; Behrens, C.; Bromberger, H.; Costello, J. T.; Czwalinna, M. K.; Felber, M.; Hoffmann, M. C.; Ilchen, M.; Liu, H. Y.; Mazza, T.; Meyer, M.; Pfeiffer, S.; Prędki, P.; Schefer, S.; Schmidt, C.; Wegner, U.; Schlarb, H.; Cavalieri, A. L.

2015-01-01

Many advanced applications of X-ray free-electron lasers require pulse durations and time resolutions of only a few femtoseconds. To generate these pulses and to apply them in time-resolved experiments, synchronization techniques that can simultaneously lock all independent components, including all accelerator modules and all external optical lasers, to better than the delivered free-electron laser pulse duration, are needed. Here we achieve all-optical synchronization at the soft X-ray free-electron laser FLASH and demonstrate facility-wide timing to better than 30 fs r.m.s. for 90 fs X-ray photon pulses. Crucially, our analysis indicates that the performance of this optical synchronization is limited primarily by the free-electron laser pulse duration, and should naturally scale to the sub-10 femtosecond level with shorter X-ray pulses. PMID:25600823

Surgery: Modified Pi with Triple-Bonnet Flap and Fronto-Orbital Advancement.

PubMed

Singh Raswan, Uday; Singh Chhiber, Sarbjit; Ramzan, Altaf Umar

2017-01-01

Craniosynostosis is the premature fusion of one or more of the cranial sutures and can occur as part of a syndrome or as an isolated defect. Pansynostosis is a rare form of craniosynostosis that involves premature fusion of all the cranial sutures (coronal, sagittal, metopic, and occipital). Particularly in cases of late presentation, there are heightened clinical concerns, both functional and aesthetic. In untreated cases of pansynostosis and increased intracranial pressure, optic nerve damage progresses to optic atrophy and then blindness. Cranial vault reconstruction is the standard surgical treatment. We attempt to highlight the importance of modifying the osteotomies and reshaping of the cranial vault based on individual requirements in order to achieve the best possible result and to prevent catastrophic blood loss. We present a case of modified pi with triple-bonnet flap and fronto-orbital advancement, an individual modification of the techniques of cranial vault reconstruction, in a patient with pansynostosis with optic atrophy. The technical variation can be applied to any case of pansynostosis requiring cranial vault reconstruction. © 2017 S. Karger AG, Basel.

Current advances in molecular imaging: noninvasive in vivo bioluminescent and fluorescent optical imaging in cancer research.

PubMed

Choy, Garry; Choyke, Peter; Libutti, Steven K

2003-10-01

Recently, there has been tremendous interest in developing techniques such as MRI, micro-CT, micro-PET, and SPECT to image function and processes in small animals. These technologies offer deep tissue penetration and high spatial resolution, but compared with noninvasive small animal optical imaging, these techniques are very costly and time consuming to implement. Optical imaging is cost-effective, rapid, easy to use, and can be readily applied to studying disease processes and biology in vivo. In vivo optical imaging is the result of a coalescence of technologies from chemistry, physics, and biology. The development of highly sensitive light detection systems has allowed biologists to use imaging in studying physiological processes. Over the last few decades, biochemists have also worked to isolate and further develop optical reporters such as GFP, luciferase, and cyanine dyes. This article reviews the common types of fluorescent and bioluminescent optical imaging, the typical system platforms and configurations, and the applications in the investigation of cancer biology.

Recent advances in nanomaterial-based biosensors for antibiotics detection.

PubMed

Lan, Lingyi; Yao, Yao; Ping, Jianfeng; Ying, Yibin

2017-05-15

Antibiotics are able to be accumulated in human body by food chain and may induce severe influence to human health and safety. Hence, the development of sensitive and simple methods for rapid evaluation of antibiotic levels is highly desirable. Nanomaterials with excellent electronic, optical, mechanical, and thermal properties have been recognized as one of the most promising materials for opening new gates in the development of next-generation biosensors. This review highlights the current advances in the nanomaterial-based biosensors for antibiotics detection. Different kinds of nanomaterials including carbon nanomaterials, metal nanomaterials, magnetic nanoparticles, up-conversion nanoparticles, and quantum dots have been applied to the construction of biosensors with two main signal-transducing mechanisms, i.e. optical and electrochemical. Furthermore, the current challenges and future prospects in this field are also included to provide an overview for future research directions. Copyright © 2017 Elsevier B.V. All rights reserved.

Transforming Mesoscopic (Bio)materials with Holographic Optical Tweezers

NASA Astrophysics Data System (ADS)

Grier, David

2004-03-01

An optical tweezer uses the forces exerted by a strongly focused beam of light to trap and move objects ranging in size from tens of nanometers to tens of micrometers. Since their introduction in 1986, optical tweezers have become a mainstay of research in biology, physical chemistry, and soft condensed matter physics. This talk highlights recent advances made possible by new classes of optical traps created with computer-designed holograms, a technique we call holographic optical trapping. Holographic optical tweezers can trap hundreds of mesoscopic objects simultaneously and move them independently in three dimensions. Arrays of optical traps can be used to continuously sort heterogeneous samples into selected fractions, a process we call optical fractionation. The same holograms can transform optical traps into optical scalpels and scissors that photochemically transform mesoscopic samples with exquisite spatial resolution. They also can impose arbitrary phase profiles onto the trapping beams, thereby creating optical vortices and related optical machines capable of actuating MEMS devices and driving mesoscale pumps and mixers. These new applications for laser light promise to take optical tweezers out of the laboratory and into real-world applications including manufacturing, diagnostics, and even consumer products. The unprecedented access to the mesoscopic world provided by holographic optical tweezers also offers revolutionary new opportunities for fundamental and applied research.

Precision PEP-II optics measurement with an SVD-enhanced Least-Square fitting

NASA Astrophysics Data System (ADS)

Yan, Y. T.; Cai, Y.

2006-03-01

A singular value decomposition (SVD)-enhanced Least-Square fitting technique is discussed. By automatic identifying, ordering, and selecting dominant SVD modes of the derivative matrix that responds to the variations of the variables, the converging process of the Least-Square fitting is significantly enhanced. Thus the fitting speed can be fast enough for a fairly large system. This technique has been successfully applied to precision PEP-II optics measurement in which we determine all quadrupole strengths (both normal and skew components) and sextupole feed-downs as well as all BPM gains and BPM cross-plane couplings through Least-Square fitting of the phase advances and the Local Green's functions as well as the coupling ellipses among BPMs. The local Green's functions are specified by 4 local transfer matrix components R12, R34, R32, R14. These measurable quantities (the Green's functions, the phase advances and the coupling ellipse tilt angles and axis ratios) are obtained by analyzing turn-by-turn Beam Position Monitor (BPM) data with a high-resolution model-independent analysis (MIA). Once all of the quadrupoles and sextupole feed-downs are determined, we obtain a computer virtual accelerator which matches the real accelerator in linear optics. Thus, beta functions, linear coupling parameters, and interaction point (IP) optics characteristics can be measured and displayed.

Slumped glass optics for x-ray telescopes: advances in the hot slumping assisted by pressure

NASA Astrophysics Data System (ADS)

Salmaso, B.; Brizzolari, C.; Basso, S.; Civitani, M.; Ghigo, M.; Pareschi, G.; Spiga, D.; Tagliaferri, G.; Vecchi, G.

2015-09-01

Slumped Glass Optics is a viable solution to build future X-ray telescopes. In our laboratories we use a direct hot slumping approach assisted by pressure, in which the glass optical surface is in contact with the mould, and a pressure is applied to enforce the replication of the mould shape on the glass optical surface. Several prototypes have been already produced and tested in X-rays, showing a continuous improvement in our technology. In this paper, we present the advances in our technology, in terms of slumped glass foils quality and expected performances upon an ideal integration. By using Eagle XG glass foils and Zerodur K20 for the slumping mould, we have fine tuned several process parameters: we present a critical analysis correlating the changes in the process to the improvements in different spatial frequency ranges encompassing the profile and roughness measurements. The use of a re-polished K20 mould, together with the optimized process parameters, lead to the latest result of glass foils with expected performance of less than 3 arcsec in single reflection at 1 keV X-ray energy. This work presents all the relevant steps forward in the hot slumping technology assisted by pressure, aimed at reaching angular resolutions of 5 arcsec for the whole mirror assembly.

Silicon carbide optics for space and ground based astronomical telescopes

NASA Astrophysics Data System (ADS)

Robichaud, Joseph; Sampath, Deepak; Wainer, Chris; Schwartz, Jay; Peton, Craig; Mix, Steve; Heller, Court

2012-09-01

Silicon Carbide (SiC) optical materials are being applied widely for both space based and ground based optical telescopes. The material provides a superior weight to stiffness ratio, which is an important metric for the design and fabrication of lightweight space telescopes. The material also has superior thermal properties with a low coefficient of thermal expansion, and a high thermal conductivity. The thermal properties advantages are important for both space based and ground based systems, which typically need to operate under stressing thermal conditions. The paper will review L-3 Integrated Optical Systems - SSG’s (L-3 SSG) work in developing SiC optics and SiC optical systems for astronomical observing systems. L-3 SSG has been fielding SiC optical components and systems for over 25 years. Space systems described will emphasize the recently launched Long Range Reconnaissance Imager (LORRI) developed for JHU-APL and NASA-GSFC. Review of ground based applications of SiC will include supporting L-3 IOS-Brashear’s current contract to provide the 0.65 meter diameter, aspheric SiC secondary mirror for the Advanced Technology Solar Telescope (ATST).

Advanced adaptive optics technology development

NASA Astrophysics Data System (ADS)

Olivier, Scot S.

2002-02-01

The NSF Center for Adaptive Optics (CfAO) is supporting research on advanced adaptive optics technologies. CfAO research activities include development and characterization of micro-electro-mechanical systems (MEMS) deformable mirror (DM) technology, as well as development and characterization of high-resolution adaptive optics systems using liquid crystal (LC) spatial light modulator (SLM) technology. This paper presents an overview of the CfAO advanced adaptive optics technology development activities including current status and future plans.

Photonics Applications and Web Engineering: WILGA 2017

NASA Astrophysics Data System (ADS)

Romaniuk, Ryszard S.

2017-08-01

XLth Wilga Summer 2017 Symposium on Photonics Applications and Web Engineering was held on 28 May-4 June 2017. The Symposium gathered over 350 participants, mainly young researchers active in optics, optoelectronics, photonics, modern optics, mechatronics, applied physics, electronics technologies and applications. There were presented around 300 oral and poster papers in a few main topical tracks, which are traditional for Wilga, including: bio-photonics, optical sensory networks, photonics-electronics-mechatronics co-design and integration, large functional system design and maintenance, Internet of Things, measurement systems for astronomy, high energy physics experiments, and other. The paper is a traditional introduction to the 2017 WILGA Summer Symposium Proceedings, and digests some of the Symposium chosen key presentations. This year Symposium was divided to the following topical sessions/conferences: Optics, Optoelectronics and Photonics, Computational and Artificial Intelligence, Biomedical Applications, Astronomical and High Energy Physics Experiments Applications, Material Research and Engineering, and Advanced Photonics and Electronics Applications in Research and Industry.

Fabrication of reduced graphene oxide nanosheets doped PVA composite films for tailoring their opto-mechanical properties

NASA Astrophysics Data System (ADS)

Aslam, Muhammad; Kalyar, Mazhar Ali; Raza, Zulfiqar Ali

2017-06-01

Laminar graphene nanosheets have raised passionate attention due to their incredible physico-chemical properties. Its wide-scale, high-yield production at low-cost has made it possible to produce top class promising versatile polymer nanocomposites. Reduced graphene oxide (RGO) nanosheets were incorporated to prepare optically tunable and high mechanical strength polymer nanocomposite films. RGO-doped poly(vinyl alcohol) (PVA) nanocomposite films were prepared via solution casting. Low level RGO doping significantly altered the structural, optical and mechanical properties of pure PVA films. Most of the band structure parameters like direct/indirect band gap, band tail, refractive index, dielectric constant, optical conductivity and dispersion parameters were investigated in detail for the first time. Tauc's, Wemple-DiDomenico, Helpin-Tsai and mixture rule models were employed to investigate optical and mechanical parameters. The applied models reinforced the experimental results in the present study. Advanced analytical techniques were engaged to characterize the nanocomposites films.

Coherent Optical Memory with High Storage Efficiency and Large Fractional Delay

NASA Astrophysics Data System (ADS)

Chen, Yi-Hsin; Lee, Meng-Jung; Wang, I.-Chung; Du, Shengwang; Chen, Yong-Fan; Chen, Ying-Cheng; Yu, Ite A.

2013-02-01

A high-storage efficiency and long-lived quantum memory for photons is an essential component in long-distance quantum communication and optical quantum computation. Here, we report a 78% storage efficiency of light pulses in a cold atomic medium based on the effect of electromagnetically induced transparency. At 50% storage efficiency, we obtain a fractional delay of 74, which is the best up-to-date record. The classical fidelity of the recalled pulse is better than 90% and nearly independent of the storage time, as confirmed by the direct measurement of phase evolution of the output light pulse with a beat-note interferometer. Such excellent phase coherence between the stored and recalled light pulses suggests that the current result may be readily applied to single photon wave packets. Our work significantly advances the technology of electromagnetically induced transparency-based optical memory and may find practical applications in long-distance quantum communication and optical quantum computation.

Coherent optical memory with high storage efficiency and large fractional delay.

PubMed

Chen, Yi-Hsin; Lee, Meng-Jung; Wang, I-Chung; Du, Shengwang; Chen, Yong-Fan; Chen, Ying-Cheng; Yu, Ite A

2013-02-22

A high-storage efficiency and long-lived quantum memory for photons is an essential component in long-distance quantum communication and optical quantum computation. Here, we report a 78% storage efficiency of light pulses in a cold atomic medium based on the effect of electromagnetically induced transparency. At 50% storage efficiency, we obtain a fractional delay of 74, which is the best up-to-date record. The classical fidelity of the recalled pulse is better than 90% and nearly independent of the storage time, as confirmed by the direct measurement of phase evolution of the output light pulse with a beat-note interferometer. Such excellent phase coherence between the stored and recalled light pulses suggests that the current result may be readily applied to single photon wave packets. Our work significantly advances the technology of electromagnetically induced transparency-based optical memory and may find practical applications in long-distance quantum communication and optical quantum computation.

Science and technology of stressed liquid crystals: display and non-display applications

NASA Astrophysics Data System (ADS)

Melnyk, Olha; Garbovskiy, Yuriy; Glushchenko, Anatoliy

2017-08-01

Stressed liquid crystals (SLCs) have emerged as promising tunable electro-optical materials more than a decade ago. They are optically transparent and are characterized by a giant phase modulation of the incident light (Nπ, N >> 1), fast (millisecond and shorter) electro-optical response, and a relatively low driving voltage (∼1 V/μm). Surprisingly, despite their advanced electro-optical performance, these new materials did not receive due attention in the research community. One possible reason of such an inadequate interest in SLCs is the lack of the well-documented procedure describing how to actually produce these materials. This paper is aimed at the development of such a step-by-step practical guide suitable for experimentalist and engineers. The proposed technology is applied to produce and characterize SLCs. In addition, some applications of the materials are briefly discussed and a broader overview of their possible use is outlined.

Applications of in situ optical measurements in ecological and biogeochemical studies - a framework for a user-driven national network

NASA Astrophysics Data System (ADS)

Bergamaschi, B. A.; Pellerin, B. A.; Downing, B. D.; Saraceno, J.; Aiken, G.; Stumpner, P.

2010-12-01

A critical challenge for understanding the dynamics between water quality, and ecological processes is obtaining data at time scales in which changes occur. Traditional, discrete sampling, approaches for data collection are often limited by analytical and field costs, site access, and logistical challenges, for long-term sampling at a large number of sites. The timescales of change, however, are often minutes, hours, or years. In situ optical (absorbance and fluorescence) instruments offer opportunities to help overcome these difficulties by directly or indirectly measuring constituents of interest. In situ optical instrumentation have been in use in oceanographic studies for well over 50 years, and as advances in the science, engineering and technology of these sensors have improved, optical sensors have become more commercially viable and available for research. We present several examples that highlight applications of in situ optical measurements for understanding dynamics in stream, river, and estuary systems. Examples illustrate the utility of in situ optical sensors for studies over short-duration events of days to weeks (diurnal cycles, tidal cycles, storm events and snowmelt periods) as well as longer-term continuous monitoring for months to years. We also highlight applied in situ optical measurements as proxies for constituents that are difficult and expensive to measure at high spatiotemporal resolution, for example, dissolved organic carbon, dissolved organic nitrogen, mercury and methylmercury, trihalomethane precursors, harmful algal blooms, and others. We propose that relatively simple absorbance and fluorescence measurements made in situ could be incorporated into short and long-term ecological research and monitoring programs, resulting in advanced understanding of sources that contribute to water quality improvements or degradation, contaminant and carbon cycling, and the occurrence and persistence of harmful algal blooms. Linking these efforts through common calibration and validation techniques, as well as hosted data sharing and online user forums - as has been proposed by CUAHSI and USGS - will permit more rapid advances in applications of in situ optical sensors as well as in our understanding of aquatic processes.

Surface Wave Cloak from Graded Refractive Index Nanocomposites

PubMed Central

La Spada, L.; McManus, T. M.; Dyke, A.; Haq, S.; Zhang, L.; Cheng, Q.; Hao, Y.

2016-01-01

Recently, a great deal of interest has been re-emerged on the possibility to manipulate surface waves, in particular, towards the THz and optical regime. Both concepts of Transformation Optics (TO) and metamaterials have been regarded as one of key enablers for such applications in applied electromagnetics. In this paper, we experimentally demonstrate for the first time a dielectric surface wave cloak from engineered gradient index materials to illustrate the possibility of using nanocomposites to control surface wave propagation through advanced additive manufacturing. The device is designed analytically and validated through numerical simulations and measurements, showing good agreement and performance as an effective surface wave cloak. The underlying design approach has much wider applications, which span from microwave to optics for the control of surface plasmon polaritons (SPPs) and radiation of nanoantennas. PMID:27416815

Time-of-Flight Tip-Clearance Measurements

NASA Technical Reports Server (NTRS)

Dhadwal, H. S.; Kurkov, A. P.; Janetzke, D. C.

1999-01-01

In this paper a time-of-flight probe system incorporating the two integrated fiber optic probes which are tilted equally relative to the probe holder centerline, is applied for the first time to measure the tip clearance of an advanced fan prototype. Tip clearance is largely independent of the signal amplitude and it relies on timing measurement. This work exposes optical effects associated with the fan blade stagger angle that were absent during the original spin-rig experiment on the zero stagger rotor. Individual blade tip clearances were measured with accuracy of +/- 127-mm (+/- 0.005-in). Probe features are discussed and improvements to the design are suggested.

Advanced laser modeling with BLAZE multiphysics

NASA Astrophysics Data System (ADS)

Palla, Andrew D.; Carroll, David L.; Gray, Michael I.; Suzuki, Lui

2017-01-01

The BLAZE Multiphysics™ software simulation suite was specifically developed to model highly complex multiphysical systems in a computationally efficient and highly scalable manner. These capabilities are of particular use when applied to the complexities associated with high energy laser systems that combine subsonic/transonic/supersonic fluid dynamics, chemically reacting flows, laser electronics, heat transfer, optical physics, and in some cases plasma discharges. In this paper we present detailed cw and pulsed gas laser calculations using the BLAZE model with comparisons to data. Simulations of DPAL, XPAL, ElectricOIL (EOIL), and the optically pumped rare gas laser were found to be in good agreement with experimental data.

Chemical, biochemical, and environmental fiber sensors IV; Proceedings of the Meeting, Boston, MA, Sept. 8, 9, 1992

NASA Astrophysics Data System (ADS)

Lieberman, Robert A.

Various paper on chemical, biochemical, and environmental fiber sensors are presented. Some of the individual topics addressed include: evanescent-wave fiber optic (FO) biosensor, refractive-index sensors based on coupling to high-index multimode overlays, advanced technique in FO sensors, design of luminescence-based temperature sensors, NIR fluorescence in FO applications, FO sensor based on microencapsulated reagents, emitters and detectors for optical gas and chemical sensing, tunable fiber laser source for methane detection at 1.68 micron, FO fluorometer based on a dual-wavelength laser excitation source, thin polymer films as active components of FO chemical sensors, submicron optical sources for single macromolecule detection, nanometer optical fiber pH sensor. Also discussed are: microfabrication of optical sensor array, luminescent FO sensor for the measurement of pH, time-domain fluorescence methods as applied to pH sensing, characterization of a sol-gel-entrapped artificial receptor, FO technology for nuclear waste cleanup, spectroscopic gas sensing with IR hollow waveguides, dissolved-oxygen quenching of in situ fluorescence measurements.

Integration of optical measurement methods with flight parameter measurement systems

NASA Astrophysics Data System (ADS)

Kopecki, Grzegorz; Rzucidlo, Pawel

2016-05-01

During the AIM (advanced in-flight measurement techniques) and AIM2 projects, innovative modern techniques were developed. The purpose of the AIM project was to develop optical measurement techniques dedicated for flight tests. Such methods give information about aircraft elements deformation, thermal loads or pressure distribution, etc. In AIM2 the development of optical methods for flight testing was continued. In particular, this project aimed at the development of methods that could be easily applied in flight tests in an industrial setting. Another equally important task was to guarantee the synchronization of the classical measuring system with cameras. The PW-6U glider used in flight tests was provided by the Rzeszów University of Technology. The glider had all the equipment necessary for testing the IPCT (image pattern correlation technique) and IRT (infrared thermometry) methods. Additionally, equipment adequate for the measurement of typical flight parameters, registration and analysis has been developed. This article describes the designed system, as well as presenting the system’s application during flight tests. Additionally, the results obtained in flight tests show certain limitations of the IRT method as applied.

Terahertz magneto-optical properties of bi- and tri-layer graphene

NASA Astrophysics Data System (ADS)

Mei, Hongying; Xu, Wen; Wang, Chao; Yuan, Haifeng; Zhang, Chao; Ding, Lan; Zhang, Jin; Deng, Chao; Wang, Yifan; Peeters, Francois M.

2018-05-01

Magneto-optical (MO) properties of bi- and tri-layer graphene are investigated utilizing terahertz time-domain spectroscopy (THz TDS) in the presence of a strong magnetic field at room-temperature. In the Faraday configuration and applying optical polarization measurements, we measure the real and imaginary parts of the longitudinal and transverse MO conductivities of different graphene samples. The obtained experimental data fits very well with the classical MO Drude formula. Thus, we are able to obtain the key sample and material parameters of bi- and tri-layer graphene, such as the electron effective mass, the electronic relaxation time and the electron density. It is found that in high magnetic fields the electronic relaxation time τ for bi- and tri-layer graphene increases with magnetic field B roughly in a form τ∼ B2 . Most importantly, we obtain the electron effective mass for bi- and tri-layer graphene at room-temperature under non-resonant conditions. This work shows how the advanced THz MO techniques can be applied for the investigation into fundamental physics properties of atomically thin 2D electronic systems.

A new calibration code for the JET polarimeter.

PubMed

Gelfusa, M; Murari, A; Gaudio, P; Boboc, A; Brombin, M; Orsitto, F P; Giovannozzi, E

2010-05-01

An equivalent model of JET polarimeter is presented, which overcomes the drawbacks of previous versions of the fitting procedures used to provide calibrated results. First of all the signal processing electronics has been simulated, to confirm that it is still working within the original specifications. Then the effective optical path of both the vertical and lateral chords has been implemented to produce the calibration curves. The principle approach to the model has allowed obtaining a unique procedure which can be applied to any manual calibration and remains constant until the following one. The optical model of the chords is then applied to derive the plasma measurements. The results are in good agreement with the estimates of the most advanced full wave propagation code available and have been benchmarked with other diagnostics. The devised procedure has proved to work properly also for the most recent campaigns and high current experiments.

Advanced astigmatism-corrected tandem Wadsworth mounting for small-scale spectral broadband imaging spectrometer.

PubMed

Lei, Yu; Lin, Guan-yu

2013-01-01

Tandem gratings of double-dispersion mount make it possible to design an imaging spectrometer for the weak light observation with high spatial resolution, high spectral resolution, and high optical transmission efficiency. The traditional tandem Wadsworth mounting is originally designed to match the coaxial telescope and large-scale imaging spectrometer. When it is used to connect the off-axis telescope such as off-axis parabolic mirror, it presents lower imaging quality than to connect the coaxial telescope. It may also introduce interference among the detector and the optical elements as it is applied to the short focal length and small-scale spectrometer in a close volume by satellite. An advanced tandem Wadsworth mounting has been investigated to deal with the situation. The Wadsworth astigmatism-corrected mounting condition for which is expressed as the distance between the second concave grating and the imaging plane is calculated. Then the optimum arrangement for the first plane grating and the second concave grating, which make the anterior Wadsworth condition fulfilling each wavelength, is analyzed by the geometric and first order differential calculation. These two arrangements comprise the advanced Wadsworth mounting condition. The spectral resolution has also been calculated by these conditions. An example designed by the optimum theory proves that the advanced tandem Wadsworth mounting performs excellently in spectral broadband.

The fundus photo has met its match: optical coherence tomography and adaptive optics ophthalmoscopy are here to stay.

PubMed

Morgan, Jessica I W

2016-05-01

Over the past 25 years, optical coherence tomography (OCT) and adaptive optics (AO) ophthalmoscopy have revolutionised our ability to non-invasively observe the living retina. The purpose of this review is to highlight the techniques and human clinical applications of recent advances in OCT and adaptive optics scanning laser/light ophthalmoscopy (AOSLO) ophthalmic imaging. Optical coherence tomography retinal and optic nerve head (ONH) imaging technology allows high resolution in the axial direction resulting in cross-sectional visualisation of retinal and ONH lamination. Complementary AO ophthalmoscopy gives high resolution in the transverse direction resulting in en face visualisation of retinal cell mosaics. Innovative detection schemes applied to OCT and AOSLO technologies (such as spectral domain OCT, OCT angiography, confocal and non-confocal AOSLO, fluorescence, and AO-OCT) have enabled high contrast between retinal and ONH structures in three dimensions and have allowed in vivo retinal imaging to approach that of histological quality. In addition, both OCT and AOSLO have shown the capability to detect retinal reflectance changes in response to visual stimuli, paving the way for future studies to investigate objective biomarkers of visual function at the cellular level. Increasingly, these imaging techniques are being applied to clinical studies of the normal and diseased visual system. Optical coherence tomography and AOSLO technologies are capable of elucidating the structure and function of the retina and ONH noninvasively with unprecedented resolution and contrast. The techniques have proven their worth in both basic science and clinical applications and each will continue to be utilised in future studies for many years to come. © 2016 The Authors Ophthalmic & Physiological Optics © 2016 The College of Optometrists.

Ultrafast all-optical arithmetic logic based on hydrogenated amorphous silicon microring resonators

NASA Astrophysics Data System (ADS)

Gostimirovic, Dusan; Ye, Winnie N.

2016-03-01

For decades, the semiconductor industry has been steadily shrinking transistor sizes to fit more performance into a single silicon-based integrated chip. This technology has become the driving force for advances in education, transportation, and health, among others. However, transistor sizes are quickly approaching their physical limits (channel lengths are now only a few silicon atoms in length), and Moore's law will likely soon be brought to a stand-still despite many unique attempts to keep it going (FinFETs, high-k dielectrics, etc.). This technology must then be pushed further by exploring (almost) entirely new methodologies. Given the explosive growth of optical-based long-haul telecommunications, we look to apply the use of high-speed optics as a substitute to the digital model; where slow, lossy, and noisy metal interconnections act as a major bottleneck to performance. We combine the (nonlinear) optical Kerr effect with a single add-drop microring resonator to perform the fundamental AND-XOR logical operations of a half adder, by all-optical means. This process is also applied to subtraction, higher-order addition, and the realization of an all-optical arithmetic logic unit (ALU). The rings use hydrogenated amorphous silicon as a material with superior nonlinear properties to crystalline silicon, while still maintaining CMOS-compatibility and the many benefits that come with it (low cost, ease of fabrication, etc.). Our method allows for multi-gigabit-per-second data rates while maintaining simplicity and spatial minimalism in design for high-capacity manufacturing potential.

Electric Field Distortion in Electro-Optical Devices Subjected to Ionizing Radiation.

DTIC Science & Technology

1983-12-26

applies- ties of scientif ic advances to nam military spae system . Versatilty and flaxibility hews beon developed to a high degree by the lehoratory...personel In deeling with the many problems encountered ina the nation’s rapidly dsvelopnas space system . 1expertise In the latest scientific developments is...desiga, distributed architectures for spacoerne m o putars, fault-tolerant c.speter system , artificia intelligence. end microelectronics applications

NATO Advanced Research Workshop: Optics of Biological Particles. Held in Novosibirsk, Russia on 3-6 Oct 2005

DTIC Science & Technology

2005-01-01

acterization of health relevant bacteria should be critically discussed, and experimentally further evidenced. References [1] D. Naumann, « Infrared spectroscopy ...application of conventional meth- ods for characterizing protein conformational transformations. Raman spectroscopy has been proven to be an efficient...appli- cation of deep ultraviolet res- onance Raman spectroscopy for structural characteriza- tion of a protein at all stages of fibrillation process

Effects of 780 nm Optical Illumination on Loss in Superconducting Microwave Resonator

NASA Astrophysics Data System (ADS)

Budoyo, R. P.; Hertzberg, J. B.; Ballard, C. J.; Voigt, K. D.; Hoffman, J. E.; Grover, J. A.; Solano, P.; Lee, J.; Rolston, S. L.; Orozco, L. A.; Anderson, J. R.; Lobb, C. J.; Wellstood, F. C.

2015-03-01

Understanding the effects of light incident on a superconducting circuit is an important step toward building a hybrid quantum system where a superconducting qubit or resonator is coupled to atoms trapped on a tapered optical fiber. We fabricated a microscale thin-film Al superconducting LC resonator (frequency 6.72 GHz) on sapphire substrate and mounted it inside an Al 3d cavity (TE101 mode frequency 7.50 GHz). Using an optical fiber, we illuminated the resonator with 780 nm light, and measured the change in internal quality factor and resonant frequency of the resonator as a function of applied optical power. The results suggest that the illumination causes an increase in rf drive-dependent dissipation. While optical illumination is expected to enhance dissipation due to quasiparticles, rf drive dependence is more typically seen in two-level-system dissipation. We compare the results with the change in loss from increased resonator temperature, and discuss various mechanisms of loss from optical illumination. Work supported by NSF through the Physics Frontier Center at the Joint Quantum Institute (JQI), and by the Center of Nanophysics and Advanced Materials (CNAM).

Advancing semiconductor-electrocatalyst systems: application of surface transformation films and nanosphere lithography.

PubMed

Brinkert, Katharina; Richter, Matthias H; Akay, Ömer; Giersig, Michael; Fountaine, Katherine T; Lewerenz, Hans-Joachim

2018-05-24

Photoelectrochemical (PEC) cells offer the possibility of carbon-neutral solar fuel production through artificial photosynthesis. The pursued design involves technologically advanced III-V semiconductor absorbers coupled via an interfacial film to an electrocatalyst layer. These systems have been prepared by in situ surface transformations in electrochemical environments. High activity nanostructured electrocatalysts are required for an efficiently operating cell, optimized in their optical and electrical properties. We demonstrate that shadow nanosphere lithography (SNL) is an auspicious tool to systematically create three-dimensional electrocatalyst nanostructures on the semiconductor photoelectrode through controlling their morphology and optical properties. First results are demonstrated by means of the photoelectrochemical production of hydrogen on p-type InP photocathodes where hitherto applied photoelectrodeposition and SNL-deposited Rh electrocatalysts are compared based on their J-V and spectroscopic behavior. We show that smaller polystyrene particle masks achieve higher defect nanostructures of rhodium on the photoelectrode which leads to a higher catalytic activity and larger short circuit currents. Structural analyses including HRSEM and the analysis of the photoelectrode surface composition by using photoelectron spectroscopy support and complement the photoelectrochemical observations. The optical performance is further compared to theoretical models of the nanostructured photoelectrodes on light scattering and propagation.

Fine tuning of optical signals in nanoporous anodic alumina photonic crystals by apodized sinusoidal pulse anodisation.

PubMed

Santos, Abel; Law, Cheryl Suwen; Chin Lei, Dominique Wong; Pereira, Taj; Losic, Dusan

2016-11-03

In this study, we present an advanced nanofabrication approach to produce gradient-index photonic crystal structures based on nanoporous anodic alumina. An apodization strategy is for the first time applied to a sinusoidal pulse anodisation process in order to engineer the photonic stop band of nanoporous anodic alumina (NAA) in depth. Four apodization functions are explored, including linear positive, linear negative, logarithmic positive and logarithmic negative, with the aim of finely tuning the characteristic photonic stop band of these photonic crystal structures. We systematically analyse the effect of the amplitude difference (from 0.105 to 0.840 mA cm -2 ), the pore widening time (from 0 to 6 min), the anodisation period (from 650 to 950 s) and the anodisation time (from 15 to 30 h) on the quality and the position of the characteristic photonic stop band and the interferometric colour of these photonic crystal structures using the aforementioned apodization functions. Our results reveal that a logarithmic negative apodisation function is the most optimal approach to obtain unprecedented well-resolved and narrow photonic stop bands across the UV-visible-NIR spectrum of NAA-based gradient-index photonic crystals. Our study establishes a fully comprehensive rationale towards the development of unique NAA-based photonic crystal structures with finely engineered optical properties for advanced photonic devices such as ultra-sensitive optical sensors, selective optical filters and all-optical platforms for quantum computing.

Computational code in atomic and nuclear quantum optics: Advanced computing multiphoton resonance parameters for atoms in a strong laser field

NASA Astrophysics Data System (ADS)

Glushkov, A. V.; Gurskaya, M. Yu; Ignatenko, A. V.; Smirnov, A. V.; Serga, I. N.; Svinarenko, A. A.; Ternovsky, E. V.

2017-10-01

The consistent relativistic energy approach to the finite Fermi-systems (atoms and nuclei) in a strong realistic laser field is presented and applied to computing the multiphoton resonances parameters in some atoms and nuclei. The approach is based on the Gell-Mann and Low S-matrix formalism, multiphoton resonance lines moments technique and advanced Ivanov-Ivanova algorithm of calculating the Green’s function of the Dirac equation. The data for multiphoton resonance width and shift for the Cs atom and the 57Fe nucleus in dependence upon the laser intensity are listed.

Plasmofluidics: Merging Light and Fluids at the Micro-/Nano-Scale

PubMed Central

Wang, Mingsong; Zhao, Chenglong; Miao, Xiaoyu; Zhao, Yanhui; Rufo, Joseph

2016-01-01

Plasmofluidics is the synergistic integration of plasmonics and micro/nano fluidics in devices and applications in order to enhance performance. There has been significant progress in the emerging field of plasmofluidics in recent years. By utilizing the capability of plasmonics to manipulate light at the nanoscale, combined with the unique optical properties of fluids, and precise manipulation via micro/nano fluidics, plasmofluidic technologies enable innovations in lab-on-a-chip systems, reconfigurable photonic devices, optical sensing, imaging, and spectroscopy. In this review article, we examine and categorize the most recent advances in plasmofluidics into plasmon-enhanced functionalities in microfluidics and microfluidics-enhanced plasmonic devices. The former focuses on plasmonic manipulations of fluids, bubbles, particles, biological cells, and molecules at the micro-/nano-scale. The latter includes technological advances that apply microfluidic principles to enable reconfigurable plasmonic devices and performance-enhanced plasmonic sensors. We conclude with our perspectives on the upcoming challenges, opportunities, and the possible future directions of the emerging field of plasmofluidics. PMID:26140612

Plasmofluidics: Merging Light and Fluids at the Micro-/Nanoscale.

PubMed

Wang, Mingsong; Zhao, Chenglong; Miao, Xiaoyu; Zhao, Yanhui; Rufo, Joseph; Liu, Yan Jun; Huang, Tony Jun; Zheng, Yuebing

2015-09-16

Plasmofluidics is the synergistic integration of plasmonics and micro/nanofluidics in devices and applications in order to enhance performance. There has been significant progress in the emerging field of plasmofluidics in recent years. By utilizing the capability of plasmonics to manipulate light at the nanoscale, combined with the unique optical properties of fluids and precise manipulation via micro/nanofluidics, plasmofluidic technologies enable innovations in lab-on-a-chip systems, reconfigurable photonic devices, optical sensing, imaging, and spectroscopy. In this review article, the most recent advances in plasmofluidics are examined and categorized into plasmon-enhanced functionalities in microfluidics and microfluidics-enhanced plasmonic devices. The former focuses on plasmonic manipulations of fluids, bubbles, particles, biological cells, and molecules at the micro/nanoscale. The latter includes technological advances that apply microfluidic principles to enable reconfigurable plasmonic devices and performance-enhanced plasmonic sensors. The article is concluded with perspectives on the upcoming challenges, opportunities, and possible future directions of the emerging field of plasmofluidics. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Digital Avionics

NASA Technical Reports Server (NTRS)

Koelbl, Terry G.; Ponchak, Denise; Lamarche, Teresa

2002-01-01

The field of digital avionics experienced another year of important advances in civil aviation, military systems, and space applications. As a result of the events of 9/11/2001, NASA has pursued activities to apply its aerospace technologies toward improved aviation security. Both NASA Glenn Research Center and Langley Research Center have performed flight research demonstrations using advanced datalink concepts to transmit live pictures from inside a jetliner, and to downlink the contents of the plane's 'black box' recorder in real time. The U.S. Navy and General Electric demonstrated survivable engine control (SEC) algorithms during engine ground tests at the Weapons Survivability Laboratory at China Lake. The scientists at Boeing Satellite Systems advanced the field of stellar inertial technology with the development of a new method for positioning optical star trackers on satellites.

Instrumentation and Controls Division Overview: Sensors Development for Harsh Environments at Glenn Research Center

NASA Technical Reports Server (NTRS)

Zeller, Mary V.; Lei, Jih-Fen

2002-01-01

The Instrumentation and Controls Division is responsible for planning, conducting and directing basic and applied research on advanced instrumentation and controls technologies for aerospace propulsion and power applications. The Division's advanced research in harsh environment sensors, high temperature high power electronics, MEMS (microelectromechanical systems), nanotechnology, high data rate optical instrumentation, active and intelligent controls, and health monitoring and management will enable self-feeling, self-thinking, self-reconfiguring and self-healing Aerospace Propulsion Systems. These research areas address Agency challenges to deliver aerospace systems with reduced size and weight, and increased functionality and intelligence for future NASA missions in advanced aeronautics, economical space transportation, and pioneering space exploration. The Division also actively supports educational and technology transfer activities aimed at benefiting all humankind.

The fundus photo has met its match: optical coherence tomography and adaptive optics ophthalmoscopy are here to stay

PubMed Central

Morgan, Jessica I. W.

2016-01-01

Purpose Over the past 25 years, optical coherence tomography (OCT) and adaptive optics (AO) ophthalmoscopy have revolutionised our ability to non-invasively observe the living retina. The purpose of this review is to highlight the techniques and human clinical applications of recent advances in OCT and adaptive optics scanning laser/light ophthalmoscopy (AOSLO) ophthalmic imaging. Recent findings Optical coherence tomography retinal and optic nerve head (ONH) imaging technology allows high resolution in the axial direction resulting in cross-sectional visualisation of retinal and ONH lamination. Complementary AO ophthalmoscopy gives high resolution in the transverse direction resulting in en face visualisation of retinal cell mosaics. Innovative detection schemes applied to OCT and AOSLO technologies (such as spectral domain OCT, OCT angiography, confocal and non-confocal AOSLO, fluorescence, and AO-OCT) have enabled high contrast between retinal and ONH structures in three dimensions and have allowed in vivo retinal imaging to approach that of histological quality. In addition, both OCT and AOSLO have shown the capability to detect retinal reflectance changes in response to visual stimuli, paving the way for future studies to investigate objective biomarkers of visual function at the cellular level. Increasingly, these imaging techniques are being applied to clinical studies of the normal and diseased visual system. Summary Optical coherence tomography and AOSLO technologies are capable of elucidating the structure and function of the retina and ONH noninvasively with unprecedented resolution and contrast. The techniques have proven their worth in both basic science and clinical applications and each will continue to be utilised in future studies for many years to come. PMID:27112222

Feedback control of thermal lensing in a high optical power cavity.

PubMed

Fan, Y; Zhao, C; Degallaix, J; Ju, L; Blair, D G; Slagmolen, B J J; Hosken, D J; Brooks, A F; Veitch, P J; Munch, J

2008-10-01

This paper reports automatic compensation of strong thermal lensing in a suspended 80 m optical cavity with sapphire test mass mirrors. Variation of the transmitted beam spot size is used to obtain an error signal to control the heating power applied to the cylindrical surface of an intracavity compensation plate. The negative thermal lens created in the compensation plate compensates the positive thermal lens in the sapphire test mass, which was caused by the absorption of the high intracavity optical power. The results show that feedback control is feasible to compensate the strong thermal lensing expected to occur in advanced laser interferometric gravitational wave detectors. Compensation allows the cavity resonance to be maintained at the fundamental mode, but the long thermal time constant for thermal lensing control in fused silica could cause difficulties with the control of parametric instabilities.

Fiber optics for advanced aircraft

NASA Technical Reports Server (NTRS)

Baumbick, Robert J.

1989-01-01

The increased use of composites makes the digital control more susceptible to electromagnetic effects. In order to provide the protection to the digital control additional shielding will be required as well as protective circuitry for the electronics. This results in increased weight and reduced reliability. The advantages that fiber optic technology provides for advanced aircraft applications is recognized. The use of optical signals to carry information between the aircraft and the control module provides immunity from contamination by electromagnetic sources as well as other important benefits such as reduced weight and volume resulting from the elimination of the shielding and the replacement of metal conductors with low weight glass fibers. In 1975 NASA began work to develop passive optical sensors for use with fiber optics in aircraft control systems. The problem now is to choose the best optical sensor concepts and evaluate them for use. In 1985 NASA and DOD entered into a joint program, Fiber Optic Control System Integration (FOCSI), to look at optical technology specifically for use in advanced aircraft systems. The results of this program are discussed. The conclusion of the study indicated that the use of fiber optic technology in advanced aircraft systems is feasible and desirable. The study pointed to a lack of available sensors from vendors capable of operating in the adverse environments of advanced aircraft.

Fiber optics for advanced aircraft

NASA Technical Reports Server (NTRS)

Baumbick, Robert J.

1988-01-01

The increased use of composites makes the digital control more susceptible to electromagnetic effects. In order to provide the protection to the digital control additional shielding will be required as well as protective circuitry for the electronics. This results in increased weight and reduced reliability. The advantages that fiber optic technology provides for advanced aircraft applications is recognized. The use of optical signals to carry information between the aircraft and the control module provides immunity from contamination by electromagnetic sources as well as other important benefits such as reduced weight and volume resulting from the elimination of the shielding and the replacement of metal conductors with low weight glass fibers. In 1975 NASA began work to develop passive optical sensors for use with fiber optics in aircraft control systems. The problem now is to choose the best optical sensor concepts and evaluate them for use. In 1985 NASA and DOD entered into a joint program, Fiber Optic Control System Integration (FOCSI), to look at optical technology specifically for use in advanced aircraft systems. The results of this program are discussed. The conclusion of the study indicated that the use of fiber optic technology in advanced aircraft systems is feasible and desirable. The study pointed to a lack of available sensors from vendors capable of operating in the adverse environments of advanced aircraft.

Quantitative characterization of optic nerve atrophy in patients with multiple sclerosis

PubMed Central

Smith, Alex K; Lyttle, Bailey; Box, Bailey; Landman, Bennett A; Bagnato, Francesca; Pawate, Siddharama; Smith, Seth A

2017-01-01

Background Optic neuritis (ON) is one of the most common presentations of multiple sclerosis (MS). Magnetic resonance imaging (MRI) of the optic nerves is challenging because of retrobulbar motion, orbital fat and susceptibility artifacts from maxillary sinuses; therefore, axonal loss is investigated with the surrogate measure of a single heuristically defined point along the nerve as opposed to volumetric investigation. Objective The objective of this paper is to derive optic nerve volumetrics along the entire nerve length in patients with MS and healthy controls in vivo using high-resolution, clinically viable MRI. Methods An advanced, isotropic T2-weighted turbo spin echo MRI was applied to 29 MS patients with (14 patients ON+) or without (15 patients ON–) history of ON and 42 healthy volunteers. An automated tool was used to estimate and compare whole optic nerve and surrounding cerebrospinal fluid radii along the length of the nerve. Results and conclusion Only ON+ MS patients had a significantly reduced optic nerve radius compared to healthy controls in the central segment of the optic nerve. Using clinically available MRI methods, we show and quantify ON volume loss for the first time in MS patients. PMID:28932410

Deterministic magnetorheological finishing of optical aspheric mirrors

NASA Astrophysics Data System (ADS)

Song, Ci; Dai, Yifan; Peng, Xiaoqiang; Li, Shengyi; Shi, Feng

2009-05-01

A new method magnetorheological finishing (MRF) used for deterministical finishing of optical aspheric mirrors is applied to overcome some disadvantages including low finishing efficiency, long iterative time and unstable convergence in the process of conventional polishing. Based on the introduction of the basic principle of MRF, the key techniques to implement deterministical MRF are also discussed. To demonstrate it, a 200 mm diameter K9 class concave asphere with a vertex radius of 640mm was figured on MRF polish tool developed by ourselves. Through one process about two hours, the surface accuracy peak-to-valley (PV) is improved from initial 0.216λ to final 0.179λ and root-mean-square (RMS) is improved from 0.027λ to 0.017λ (λ = 0.6328um ). High-precision and high-efficiency convergence of optical aspheric surface error shows that MRF is an advanced optical manufacturing method that owns high convergence ratio of surface figure, high precision of optical surfacing, stabile and controllable finishing process. Therefore, utilizing MRF to finish optical aspheric mirrors determinately is credible and stabile; its advantages can be also used for finishing optical elements on varieties of types such as plane mirrors and spherical mirrors.

History of optics: a modern teaching tool

NASA Astrophysics Data System (ADS)

Vazquez, D.; Gonzalez-Cano, A.; Diaz-Herrera, N.; Llombart, N.; Alda, J.

2012-10-01

The history of optics is a very rich field of science and it is possible to find many simple and significant examples of the application and success of the experimental method and therefore is a very good tool to transmit to the student the way science proceeds and to introduce the right spirit of critical analysis, building and testing of models, etc. Optical phenomena are specially well suited for this because in fact optical observations and experiments have made science advance in a crucial way in many different periods of history, because they are in many cases quite visual, quite simple in concept and it is very easy to produce experimental setups in classrooms. Also, the intrinsic multidisciplinary character of Optics, which is a subject that has historically influenced in a notorious way fields as art, philosophy, religion and cultural and social studies in general, provide a very wide frame that permits to apply these examples to many different auditories. We present here some reflections about the role that history of optics can play in teaching and show some real examples of its application during the many years that we have been employing it in the context of the Optics School of the Complutense University of Madrid, Spain.

Evolution of colloidal dispersions in novel time-varying optical potentials

NASA Astrophysics Data System (ADS)

Koss, Brian Alan

Optical traps use forces exerted by a tightly focused light beam to trap objects from tens of nanometers to tens of micrometers in size. Since their introduction in 1986, optical tweezers have become very useful to biology, chemistry, and soft condensed-matter physics. Work presented here, promises to advance optical tweezers not only in fundamental scientific research, but also in applications outside of the laboratory and into the mainstream of miniaturized manufacturing and diagnostics. By providing unprecedented access to the mesoscopic world, a new generation of optical traps, called Dynamic Holographic Optical Tweezers (HOTs) offers revolutionary new opportunities for fundamental and applied research. To demonstrate this technique, HOTs will be used to pump particles via a new method of transport called Optical Peristalsis (OP). OP is efficient method for transporting mesoscopic objects in three dimensions using short repetitive sequences of holographic optical trapping patterns. Transport in this process is analogous to peristaltic pumping, with the configurations of optical traps mimicking states of a peristaltic pump. While not limited to the deterministic particle transport, OP, can also be a platform to investigate the stochastic limit of particle transport. Advances in recent years have demonstrated that a variety of time-varying perturbations can induce drift in a diffusive system without exerting an overall force. Among these, are thermal ratchet models in which the system is subjected to time-varying energy landscapes that break spatiotemporal symmetry and thereby induce drift. Typically, the potential energy landscape is chosen to be the sawtooth potential. This work describes an alternate class of symmetric thermal ratchet models, that are not sawtooth, and demonstrates their efficacy in biasing the diffusion of colloidal spheres in both the stochastic and deterministic limits. Unlike previous models, each state in this thermal ratchet consists of discrete spatially-symmetric potential wells, which are implemented with an array of HOTs.

Scaling of Yb-Fiber Frequency Combs

NASA Astrophysics Data System (ADS)

Ruehl, Axel; Marcinkevicius, Andrius; Fermann, Martin E.; Hartl, Ingmar

2010-06-01

Immediately after their introduction in 1999, femtosecond laser frequency combs revolutionized the field of precision optical frequency metrology and are key elements in many experiments. Frequency combs based on femtosecond Er-fiber lasers based were demonstrated in 2005, allowing additionally rugged, compact set-ups and reliable unattended long-term operation. The introduction of Yb-fiber technology led to an dramatic improvement in fiber-comb performance in various aspects. Low-noise Yb-fiber femtosecond oscillators enabled a reduction of relative comb tooth linewidth to the sub-Hz level as well as scaling of the fundamental comb spacings up to 1 GHz. This is beneficial for any frequency-domain comb application due to the higher power per comb-mode. Many spectroscopic applications require, however, frequency combs way beyond the wavelength range accessible with broad band laser materials, so nonlinear conversion and hence higher peak intensity is required. We demonstrated power scaling of Yb-fiber frequency combs up to 80 W average power in a strictly linear chirped-pulse amplification schemes compatible with low-noise phase control. These high-power Yb-fiber-frequency combs facilitated not only the extension to the mid-IR spectral region. When coupled to a passive enhancement cavity, the average power can be further scaled to the kW-level opening new capabilities for XUV frequency combs via high-harmonic generation. All these advances of fiber-based frequency combs will trigger many novel applications both in fundamental and applied sciences. Schibli et al., Nature Photonics 2 355 (2008). Hartl et al., MF9 in Advanced Solid-State Photonics. 2009, Optical Society of America. Ruehl et al., AWC7 in Advanced Solid-State Photonics. 2010, Optical Society of America. Adler et al., Optics Letters 34 1330 (2009). Yost et al., Nature Physics 5 815 (2009).

Delayed photo-emission model for beam optics codes

DOE PAGES

Jensen, Kevin L.; Petillo, John J.; Panagos, Dimitrios N.; ...

2016-11-22

Future advanced light sources and x-ray Free Electron Lasers require fast response from the photocathode to enable short electron pulse durations as well as pulse shaping, and so the ability to model delays in emission is needed for beam optics codes. The development of a time-dependent emission model accounting for delayed photoemission due to transport and scattering is given, and its inclusion in the Particle-in-Cell code MICHELLE results in changes to the pulse shape that are described. Furthermore, the model is applied to pulse elongation of a bunch traversing an rf injector, and to the smoothing of laser jitter onmore » a short pulse.« less

Effect of focusing flow on stationary spot machining properties in elastic emission machining

PubMed Central

2013-01-01

Ultraprecise optical elements are applied in advanced optical apparatus. Elastic emission machining (EEM) is one of the ultraprecision machining methods used to fabricate shapes with 0.1-nm accuracy. In this study, we proposed and experimentally tested the control of the shape of a stationary spot profile by introducing a focusing-flow state between the nozzle outlet and the workpiece surface in EEM. The simulation results indicate that the focusing-flow nozzle sharpens the distribution of the velocity on the workpiece surface. The results of machining experiments verified those of the simulation. The obtained stationary spot conditions will be useful for surface processing with a high spatial resolution. PMID:23680043

Fabrication and Metrology of High-Precision Foil Mirror Mounting Elements

NASA Technical Reports Server (NTRS)

Schattenburg, Mark L.

2002-01-01

During the period of this Cooperative Agreement, MIT (Massachusetts Institute of Technology) developed advanced methods for applying silicon microstructures for the precision assembly of foil x-ray optics in support of the Constellation-X Spectroscopy X-ray Telescope (SXT) development effort at Goddard Space Flight Center (GSFC). MIT developed improved methods for fabricating and characterizing the precision silicon micro-combs. MIT also developed and characterized assembly tools and several types of metrology tools in order to characterize and reduce the errors associated with precision assembly of foil optics. Results of this effort were published and presented to the scientific community and the GSFC SXT team. A bibliography of papers and presentations is offered.

Laser-Raman/Rayleigh Flow Diagnostic Techniques Applied to Subsonic Flow

DTIC Science & Technology

1980-10-01

the problem of interpreting test results. Advances in electronics and laser technology have made it possible to perform measurements (which formerly...will increase with increasing gas density. It was the latter quality that made the prospect for successful subsonic flow-field measurements very...elements in the optical system were made of fused silica. An aperture was located at the entrance slit of the spectrometer and adjusted so that a 0.25-in

A THz plasmonics perfect absorber and Fabry-Perot cavity mechanism (Conference Presentation)

NASA Astrophysics Data System (ADS)

Zhou, Jiangfeng; Bhattarai, Khagendra; Silva, Sinhara; Jeon, Jiyeon; Kim, Junoh; Lee, Sang Jun; Ku, Zahyun

2016-10-01

The plasmonic metamaterial perfect absorber (MPA) is a recently developed branch of metamaterial which exhibits nearly unity absorption within certain frequency range.[1-6] The optically thin MPA possesses characteristic features of angular-independence, high Q-factor and strong field localization that have inspired a wide range of applications including electromagnetic wave absorption,[3, 7, 8] spatial[6] and spectral[5] modulation of light,[9] selective thermal emission,[9] thermal detecting[10] and refractive index sensing for gas[11] and liquid[12, 13] targets. In this work, we demonstrate a MPA working at terahertz (THz) regime and characterize it using an ultrafast THz time-domain spectroscopy (THz-TDS). Our study reveal an ultra-thin Fabry-Perot cavity mechanism compared to the impedance matching mechanism widely adopted in previous study [1-6]. Our results also shows higher-order resonances when the cavities length increases. These higher order modes exhibits much larger Q-factor that can benefit potential sensing and imaging applications. [1] C. M. Watts, X. L. Liu, and W. J. Padilla, "Metamaterial Electromagnetic Wave Absorbers," Advanced Materials, vol. 24, pp. 98-120, Jun 19 2012. [2] M. Hedayati, F. Faupel, and M. Elbahri, "Review of Plasmonic Nanocomposite Metamaterial Absorber," Materials, vol. 7, pp. 1221-1248, 2014. [3] N. I. Landy, S. Sajuyigbe, J. J. Mock, D. R. Smith, and W. J. Padilla, "Perfect metamaterial absorber," Physical Review Letters, vol. 100, p. 207402, May 23 2008. [4] H. R. Seren, G. R. Keiser, L. Cao, J. Zhang, A. C. Strikwerda, K. Fan, et al., "Optically Modulated Multiband Terahertz Perfect Absorber," Advanced Optical Materials, vol. 2, pp. 1221-1226, 2014. [5] D. Shrekenhamer, J. Montoya, S. Krishna, and W. J. Padilla, "Four-Color Metamaterial Absorber THz Spatial Light Modulator," Advanced Optical Materials, vol. 1, pp. 905-909, 2013. [6] S. Savo, D. Shrekenhamer, and W. J. Padilla, "Liquid Crystal Metamaterial Absorber Spatial Light Modulator for THz Applications," Advanced Optical Materials, vol. 2, pp. 275-279, 2014. [7] H. Tao, N. I. Landy, C. M. Bingham, X. Zhang, R. D. Averitt, and W. J. Padilla, "A metamaterial absorber for the terahertz regime: Design, fabrication and characterization," Optics Express, vol. 16, pp. 7181-7188, May 12 2008. [8] J. Hao, J. Wang, X. Liu, W. J. Padilla, L. Zhou, and M. Qiu, "High performance optical absorber based on a plasmonic metamaterial," Applied Physics Letters, vol. 96, p. 251104, 2010. [9] X. Liu, T. Tyler, T. Starr, A. F. Starr, N. M. Jokerst, and W. J. Padilla, "Taming the Blackbody with Infrared Metamaterials as Selective Thermal Emitters," Physical Review Letters, vol. 107, p. 045901, 07/18/ 2011. [10] T. Maier and H. Brückl, "Wavelength-tunable microbolometers with metamaterial absorbers," Optics Letters, vol. 34, pp. 3012-3014, 2009/10/01 2009. [11] A. Tittl, P. Mai, R. Taubert, D. Dregely, N. Liu, and H. Giessen, "Palladium-Based Plasmonic Perfect Absorber in the Visible Wavelength Range and Its Application to Hydrogen Sensing," Nano Letters, vol. 11, pp. 4366-4369, 2011/10/12 2011. [12] N. Liu, M. Mesch, T. Weiss, M. Hentschel, and H. Giessen, "Infrared Perfect Absorber and Its Application As Plasmonic Sensor," Nano Letters, vol. 10, pp. 2342-2348, Jul 2010. [13] G. H. Li, X. S. Chen, O. P. Li, C. X. Shao, Y. Jiang, L. J. Huang, et al., "A novel plasmonic resonance sensor based on an infrared perfect absorber," Journal of Physics D-Applied Physics, vol. 45, p. 205102, May 23 2012.

Analytical N beam position monitor method

NASA Astrophysics Data System (ADS)

Wegscheider, A.; Langner, A.; Tomás, R.; Franchi, A.

2017-11-01

Measurement and correction of focusing errors is of great importance for performance and machine protection of circular accelerators. Furthermore LHC needs to provide equal luminosities to the experiments ATLAS and CMS. High demands are also set on the speed of the optics commissioning, as the foreseen operation with β*-leveling on luminosity will require many operational optics. A fast measurement of the β -function around a storage ring is usually done by using the measured phase advance between three consecutive beam position monitors (BPMs). A recent extension of this established technique, called the N-BPM method, was successfully applied for optics measurements at CERN, ALBA, and ESRF. We present here an improved algorithm that uses analytical calculations for both random and systematic errors and takes into account the presence of quadrupole, sextupole, and BPM misalignments, in addition to quadrupolar field errors. This new scheme, called the analytical N-BPM method, is much faster, further improves the measurement accuracy, and is applicable to very pushed beam optics where the existing numerical N-BPM method tends to fail.

Multispectral and phase-contrast diffuse optical tomography of breast cancer during neoadjuvant chemotherapy: a case study

NASA Astrophysics Data System (ADS)

Liang, Xiaoping; Zhang, Qizhi; Staal, Stephen; Grobmyer, Stephen; Jiang, Huabei

2009-02-01

Multispectral and phase-contrast diffuse optical tomography are used to track treatment progress in a patient with locally advanced invasive carcinoma of the breast cancer during neoadjuvant chemotherapy. Two types of chemotherapy treatment including four cycles of Adriamycin/Cytoxin (AC cycles) and twelve cycles of Taxol/Herceptin (TH cycles) were applied to patient. A total of eight optical exams were performed before and within the chemotherapy. Images of tissue refractive index, and absorption and scattering coefficients, as well as oxy-hemoglobin and deoxy-hemoglobin concentrations along with scattering particle volume fraction and mean diameter of cellular components were all obtained. The tumor was identified through absorption and scattering images. Tumor shrinkage was observed during the course of chemotherapy from all the optical images. Our results show that oxy-hemoglobin, deoxy-hemoglobin and total hemoglobin in tumor decreased after chemotherapy compared to that of before chemotherapy. Significant changes in tumor refractive index along with tumor cellular morphology during the entire chemotherapy are also observed.

Contributed Review: The feasibility of a fully miniaturized magneto-optical trap for portable ultracold quantum technology.

PubMed

Rushton, J A; Aldous, M; Himsworth, M D

2014-12-01

Experiments using laser cooled atoms and ions show real promise for practical applications in quantum-enhanced metrology, timing, navigation, and sensing as well as exotic roles in quantum computing, networking, and simulation. The heart of many of these experiments has been translated to microfabricated platforms known as atom chips whose construction readily lend themselves to integration with larger systems and future mass production. To truly make the jump from laboratory demonstrations to practical, rugged devices, the complex surrounding infrastructure (including vacuum systems, optics, and lasers) also needs to be miniaturized and integrated. In this paper we explore the feasibility of applying this approach to the Magneto-Optical Trap; incorporating the vacuum system, atom source and optical geometry into a permanently sealed micro-litre system capable of maintaining 10(-10) mbar for more than 1000 days of operation with passive pumping alone. We demonstrate such an engineering challenge is achievable using recent advances in semiconductor microfabrication techniques and materials.

Contributed Review: The feasibility of a fully miniaturized magneto-optical trap for portable ultracold quantum technology

NASA Astrophysics Data System (ADS)

Rushton, J. A.; Aldous, M.; Himsworth, M. D.

2014-12-01

Experiments using laser cooled atoms and ions show real promise for practical applications in quantum-enhanced metrology, timing, navigation, and sensing as well as exotic roles in quantum computing, networking, and simulation. The heart of many of these experiments has been translated to microfabricated platforms known as atom chips whose construction readily lend themselves to integration with larger systems and future mass production. To truly make the jump from laboratory demonstrations to practical, rugged devices, the complex surrounding infrastructure (including vacuum systems, optics, and lasers) also needs to be miniaturized and integrated. In this paper we explore the feasibility of applying this approach to the Magneto-Optical Trap; incorporating the vacuum system, atom source and optical geometry into a permanently sealed micro-litre system capable of maintaining 10-10 mbar for more than 1000 days of operation with passive pumping alone. We demonstrate such an engineering challenge is achievable using recent advances in semiconductor microfabrication techniques and materials.

Advanced optical modeling of TiN metal hard mask for scatterometric critical dimension metrology

NASA Astrophysics Data System (ADS)

Ebersbach, Peter; Urbanowicz, Adam M.; Likhachev, Dmitriy; Hartig, Carsten

2017-03-01

The majority of scatterometric production control models assume constant optical properties of the materials and only dimensional parameters are allowed to vary. However, this assumption, especially in case of thin-metal films, negatively impacts model precision and accuracy. In this work we focus on optical modeling of the TiN metal hardmask for scatterometry applications. Since the dielectric function of TiN exhibits thickness dependence, we had to take this fact into account. Moreover, presence of the highly absorbing films influences extracted thicknesses of dielectric layers underneath the metal films. The later phenomenon is often not reflected by goodness of fit. We show that accurate optical modeling of metal is essential to achieve desired scatterometric model quality for automatic process control in microelectronic production. Presented modeling methodology can be applied to other TiN applications such as diffusion barriers and metal gates as well as for other metals used in microelectronic manufacturing for all technology nodes.

Low Complexity Compression and Speed Enhancement for Optical Scanning Holography

PubMed Central

Tsang, P. W. M.; Poon, T.-C.; Liu, J.-P.; Kim, T.; Kim, Y. S.

2016-01-01

In this paper we report a low complexity compression method that is suitable for compact optical scanning holography (OSH) systems with different optical settings. Our proposed method can be divided into 2 major parts. First, an automatic decision maker is applied to select the rows of holographic pixels to be scanned. This process enhances the speed of acquiring a hologram, and also lowers the data rate. Second, each row of down-sampled pixels is converted into a one-bit representation with delta modulation (DM). Existing DM-based hologram compression techniques suffers from the disadvantage that a core parameter, commonly known as the step size, has to be determined in advance. However, the correct value of the step size for compressing each row of hologram is dependent on the dynamic range of the pixels, which could deviate significantly with the object scene, as well as OSH systems with different opical settings. We have overcome this problem by incorporating a dynamic step-size adjustment scheme. The proposed method is applied in the compression of holograms that are acquired with 2 different OSH systems, demonstrating a compression ratio of over two orders of magnitude, while preserving favorable fidelity on the reconstructed images. PMID:27708410

Current molecular and emerging nanobiotechnology approaches for the detection of microbial pathogens.

PubMed

Theron, Jacques; Eugene Cloete, Thomas; de Kwaadsteniet, Michele

2010-11-01

Waterborne microbial diseases are escalating worldwide increasing the need for powerful and sensitive diagnostics tools. Molecular methodologies, including immunological and nucleic acid-based methods, have only recently been applied in the water sector. Advances in nanotechnology and nanomaterials have opened the door for the development of new diagnostic tools with increased sensitivity and speed, and reduced cost and labor. Quantum dots, flo dots, gold nanoparticles, magnetic nanoparticles, carbon nanotubes, nanowires, and nanocantilevers, with their unique optical and physical properties, have already been applied in nanodiagnostics. Nanobiotechnology, once remaining technical and practical problems has been addressed, will play an important role in the detection of microbial pathogens.

Sensing systems using chip-based spectrometers

NASA Astrophysics Data System (ADS)

Nitkowski, Arthur; Preston, Kyle J.; Sherwood-Droz, Nicolás.; Behr, Bradford B.; Bismilla, Yusuf; Cenko, Andrew T.; DesRoches, Brandon; Meade, Jeffrey T.; Munro, Elizabeth A.; Slaa, Jared; Schmidt, Bradley S.; Hajian, Arsen R.

2014-06-01

Tornado Spectral Systems has developed a new chip-based spectrometer called OCTANE, the Optical Coherence Tomography Advanced Nanophotonic Engine, built using a planar lightwave circuit with integrated waveguides fabricated on a silicon wafer. While designed for spectral domain optical coherence tomography (SD-OCT) systems, the same miniaturized technology can be applied to many other spectroscopic applications. The field of integrated optics enables the design of complex optical systems which are monolithically integrated on silicon chips. The form factors of these systems can be significantly smaller, more robust and less expensive than their equivalent free-space counterparts. Fabrication techniques and material systems developed for microelectronics have previously been adapted for integrated optics in the telecom industry, where millions of chip-based components are used to power the optical backbone of the internet. We have further adapted the photonic technology platform for spectroscopy applications, allowing unheard-of economies of scale for these types of optical devices. Instead of changing lenses and aligning systems, these devices are accurately designed programmatically and are easily customized for specific applications. Spectrometers using integrated optics have large advantages in systems where size, robustness and cost matter: field-deployable devices, UAVs, UUVs, satellites, handheld scanning and more. We will discuss the performance characteristics of our chip-based spectrometers and the type of spectral sensing applications enabled by this technology.

Failure probability analysis of optical grid

NASA Astrophysics Data System (ADS)

Zhong, Yaoquan; Guo, Wei; Sun, Weiqiang; Jin, Yaohui; Hu, Weisheng

2008-11-01

Optical grid, the integrated computing environment based on optical network, is expected to be an efficient infrastructure to support advanced data-intensive grid applications. In optical grid, the faults of both computational and network resources are inevitable due to the large scale and high complexity of the system. With the optical network based distributed computing systems extensive applied in the processing of data, the requirement of the application failure probability have been an important indicator of the quality of application and an important aspect the operators consider. This paper will present a task-based analysis method of the application failure probability in optical grid. Then the failure probability of the entire application can be quantified, and the performance of reducing application failure probability in different backup strategies can be compared, so that the different requirements of different clients can be satisfied according to the application failure probability respectively. In optical grid, when the application based DAG (directed acyclic graph) is executed in different backup strategies, the application failure probability and the application complete time is different. This paper will propose new multi-objective differentiated services algorithm (MDSA). New application scheduling algorithm can guarantee the requirement of the failure probability and improve the network resource utilization, realize a compromise between the network operator and the application submission. Then differentiated services can be achieved in optical grid.

Imaging of Stellar Surfaces with the Navy Precision Optical Interferometer

DTIC Science & Technology

2015-09-18

geostationary satel- lite with the Navy Prototype Optical Interferome- ter,” in Proc. Optical and Infrared Interferometry II, W. C. Danchi, F...Cormier, “Imag- ing of geostationary satellites with the MRO inter- ferometer,” in Proc. Advanced Maui Optical and Space Surveillance Technologies... geostationary satellites: Signal-to-noise considerations,” in Proc. Advanced Maui Optical and Space Surveillance Technologies Conference, 2011. 6. D

Directed assembly of hybrid nanostructures using optically resonant nanotweezers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Erickson, David

This represents the final report for this project. Over the course of the project we have made significant progress in photonically driven nano-assembly including: (1) demonstrating the first direct optical tweezer based manipulation of proteins, (2) the ability to apply optical angular torques to microtubuals and other rod-shaped microparticles, (3) direct assembly of hybrid nanostructures comprising of polymeric nanoparticles and carbon nanotubes and, (4) the ability to drive biological reactions (specifically protein aggregation) that are thermodynamically unfavorable by applying localized optical work. These advancements are described in the list of papers provided in section 2.0 of the below. Summary detailsmore » are provided in prior year annual reports. We have two additional papers which will be submitted shortly based on the work done under this award. An updated publication list will be provided to the program manager when those are accepted. In this report, we report on a new advancement made in the final project year, which uses the nanotweezer technology to perform direct measurements of particle-surface interactions. Briefly, these measurements are important for characterizing the stability and behavior of colloidal and nanoparticle suspensions and current techniques are limited in their ability to measure piconewton scale interaction forces on sub-micrometer particles due to signal detection limits and thermal noise. In this project year we developed a new technique called “Nanophotonic Force Microscopy” which uses the localized region of exponentially decaying, near-field, light to confine small particles close to a surface. From the statistical distribution of the light intensity scattered by the particle the technique maps out the potential well of the trap and directly quantify the repulsive force between the nanoparticle and the surface. The major advantage of the technique is that it can measure forces and energy wells below the thermal noise limit, resolving interaction forces smaller than 1 pN on dielectric particles as small as 100 nm in diameter.« less

Applications of advanced electric/electronic technology to conventional aircraft

NASA Technical Reports Server (NTRS)

Heimbold, R. L.

1980-01-01

The desirability of seven advanced technologies as applied to three commercial aircraft of 1985 to 1995 was investigated. Digital fly by wire, multiplexing, ring laser gyro, integrated avionics, all electric airplane, electric load management, and fiber optics were considered for 500 passenger, 50 passenger, and 30 passenger aircraft. The major figure of merit used was Net Value of Technology based on procurement and operating cost over the life of the aircraft. An existing computer program, ASSET, was used to resize the aircraft and evalute fuel usage and maintenance costs for each candidate configuration. Conclusions were that, for the 500 passenger aircraft, all candidates had a worthwhile payoff with the all electric airplane having a large payoff.

Origins and demonstrations of electrons with orbital angular momentum

PubMed Central

Agrawal, Amit; Ercius, Peter A.; Grillo, Vincenzo; Herzing, Andrew A.; Harvey, Tyler R.; Linck, Martin; Pierce, Jordan S.

2017-01-01

The surprising message of Allen et al. (Allen et al. 1992 Phys. Rev. A 45, 8185 (doi:10.1103/PhysRevA.45.8185)) was that photons could possess orbital angular momentum in free space, which subsequently launched advancements in optical manipulation, microscopy, quantum optics, communications, many more fields. It has recently been shown that this result also applies to quantum mechanical wave functions describing massive particles (matter waves). This article discusses how electron wave functions can be imprinted with quantized phase vortices in analogous ways to twisted light, demonstrating that charged particles with non-zero rest mass can possess orbital angular momentum in free space. With Allen et al. as a bridge, connections are made between this recent work in electron vortex wave functions and much earlier works, extending a 175 year old tradition in matter wave vortices. This article is part of the themed issue ‘Optical orbital angular momentum’. PMID:28069765

Purcell effect for active tuning of light scattering from semiconductor optical antennas.

PubMed

Holsteen, Aaron L; Raza, Søren; Fan, Pengyu; Kik, Pieter G; Brongersma, Mark L

2017-12-15

Subwavelength, high-refractive index semiconductor nanostructures support optical resonances that endow them with valuable antenna functions. Control over the intrinsic properties, including their complex refractive index, size, and geometry, has been used to manipulate fundamental light absorption, scattering, and emission processes in nanostructured optoelectronic devices. In this study, we harness the electric and magnetic resonances of such antennas to achieve a very strong dependence of the optical properties on the external environment. Specifically, we illustrate how the resonant scattering wavelength of single silicon nanowires is tunable across the entire visible spectrum by simply moving the height of the nanowires above a metallic mirror. We apply this concept by using a nanoelectromechanical platform to demonstrate active tuning. Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

Online learning in optical tomography: a stochastic approach

NASA Astrophysics Data System (ADS)

Chen, Ke; Li, Qin; Liu, Jian-Guo

2018-07-01

We study the inverse problem of radiative transfer equation (RTE) using stochastic gradient descent method (SGD) in this paper. Mathematically, optical tomography amounts to recovering the optical parameters in RTE using the incoming–outgoing pair of light intensity. We formulate it as a PDE-constraint optimization problem, where the mismatch of computed and measured outgoing data is minimized with same initial data and RTE constraint. The memory and computation cost it requires, however, is typically prohibitive, especially in high dimensional space. Smart iterative solvers that only use partial information in each step is called for thereafter. Stochastic gradient descent method is an online learning algorithm that randomly selects data for minimizing the mismatch. It requires minimum memory and computation, and advances fast, therefore perfectly serves the purpose. In this paper we formulate the problem, in both nonlinear and its linearized setting, apply SGD algorithm and analyze the convergence performance.

Structural characterization on in vitro porcine skin treated by ablative fractional laser using optical coherence tomography

NASA Astrophysics Data System (ADS)

Feng, Kairui; Zhou, Kanheng; Ling, Yuting; O'Mahoney, Paul; Ewan, Eadie; Ibbotson, Sally H.; Li, Chunhui; Huang, Zhihong

2018-02-01

Ablative fractional skin laser is widely applied for various skin conditions, especially for cosmetic repairing and promoting the located drug delivery. Although the influence of laser treatment over the skin has been explored before in means of excision and biopsy with microscopy, these approaches are invasive, only morphological and capable of distorting the skin. In this paper the authors use fresh porcine skin samples irradiated by the lasers, followed by detected by using Optical Coherence Tomography (OCT). This advanced optical technique has the ability to present the high resolution structure image of treated sample. The results shows that laser beams can produce holes left on the surface after the irradiation. The depth of holes can be affected by changes of laser energy while the diameter of holes have no corresponding relation. Plus, OCT, as a valuable imaging technology, is capable of monitoring the clinical therapy procedure and assisting the calibration.

New optical engineering and instrument design programs at the University of California, Irvine Extension

NASA Astrophysics Data System (ADS)

Silberman, Donn M.; Doushkina, Valentina V.

2010-08-01

Three years ago we reported on a new optics education program established at the Irvine Center for Applied Competitive Technologies (CACT) at the Advanced Technology and Education Park (ATEP) operated by the South Orange County Community College District (SOCCCD). This paper reports on new Optical Engineering and Instrument Design Programs now being offered through the University of California, Irvine Extension. While there are some similarities between the two programs, the differences are mainly the students' level. The community college level programs were targeted primarily at technicians and junior level engineers. The university level programs are targeted at senior level engineering and physical sciences university students, graduate and post graduate students and designers in industry. This paper reviews the reasons for establishing these certificate programs and their content, the students' motivations for taking them and their employers' incentives for encouraging the students.

High-resolution imaging of the central nervous system: how novel imaging methods combined with navigation strategies will advance patient care.

PubMed

Farooq, Hamza; Genis, Helen; Alarcon, Joseph; Vuong, Barry; Jivraj, Jamil; Yang, Victor X D; Cohen-Adad, Julien; Fehlings, Michael G; Cadotte, David W

2015-01-01

This narrative review captures a subset of recent advances in imaging of the central nervous system. First, we focus on improvements in the spatial and temporal profile afforded by optical coherence tomography, fluorescence-guided surgery, and Coherent Anti-Stokes Raman Scattering Microscopy. Next, we highlight advances in the generation and uses of imaging-based atlases and discuss how this will be applied to specific clinical situations. To conclude, we discuss how these and other imaging tools will be combined with neuronavigation techniques to guide surgeons in the operating room. Collectively, this work aims to highlight emerging biomedical imaging strategies that hold potential to be a valuable tool for both clinicians and researchers in the years to come. © 2015 Elsevier B.V. All rights reserved.

Doppler optical coherence microscopy and tomography applied to inner ear mechanics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Page, Scott; Freeman, Dennis M.; Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts

While it is clear that cochlear traveling waves underlie the extraordinary sensitivity, frequency selectivity, and dynamic range of mammalian hearing, the underlying micromechanical mechanisms remain unresolved. Recent advances in low coherence measurement techniques show promise over traditional laser Doppler vibrometry and video microscopy, which are limited by low reflectivities of cochlear structures and restricted optical access. Doppler optical coherence tomography (DOCT) and Doppler optical coherence microscopy (DOCM) both utilize a broadband source to limit constructive interference of scattered light to a small axial depth called a coherence gate. The coherence gate can be swept axially to image and measure sub-nanometermore » motions of cochlear structures throughout the cochlear partition. The coherence gate of DOCT is generally narrower than the confocal gate of the focusing optics, enabling increased axial resolution (typically 15 μm) within optical sections of the cochlear partition. DOCM, frequently implemented in the time domain, centers the coherence gate on the focal plane, achieving enhanced lateral and axial resolution when the confocal gate is narrower than the coherence gate. We compare these two complementary systems and demonstrate their utility in studying cellular and micromechanical mechanisms involved in mammalian hearing.« less

Advanced space optics development in freeform optics design, ceramic polishing, rapid and extreme freeform polishing

NASA Astrophysics Data System (ADS)

Geyl, R.; Leplan, H.; Ruch, E.

2017-09-01

In this paper Safran-Reosc wants to share with the space community its recent work performed in the domain of space optics. Our main topic is a study about the advantages that freeform optical surfaces can offer to advanced space optics in term of compactness or performances. We have separated smart and extreme freeform in our design exploration work. Our second topic is to answer about the immediate question following: can we manufacture and test these freeform optics? We will therefore present our freeform optics capability, report recent achievement in extreme aspheric optics polishing and introduce to the industrialisation process of large off axis optics polishing for the ESO Extremely Large Telescope primary mirror segments. Thirdly we present our R-SiC polishing layer technology for SiC material. This technique has been developed to reduce costs, risks and schedule in the manufacturing of advanced SiC optics for Vis and IR applications.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Han, Bo-Young; Choi, Daewoong; Park, Se Hwan

Korea Atomic Energy Research Institute (KAERI) have been developing the design and deployment methodology of Laser- Induced Breakdown Spectroscopy (LIBS) instrument for safeguards application within the argon hot cell environment at Advanced spent fuel Conditioning Process Facility (ACPF), where ACPF is a facility being refurbished for the laboratory-scaled demonstration of advanced spent fuel conditioning process. LIBS is an analysis technology used to measure the emission spectra of excited elements in the local plasma of a target material induced by a laser. The spectra measured by LIBS are analyzed to verify the quality and quantity of the specific element in themore » target matrix. Recently LIBS has been recognized as a promising technology for safeguards purposes in terms of several advantages including a simple sample preparation and in-situ analysis capability. In particular, a feasibility study of LIBS to remotely monitor the nuclear material in a high radiation environment has been carried out for supporting the IAEA safeguards implementation. Fiber-Optic LIBS (FO-LIBS) deployment was proposed by Applied Photonics Ltd because the use of fiber optics had benefited applications of LIBS by delivering the laser energy to the target and by collecting the plasma light. The design of FO-LIBS instrument for the measurement of actinides in the spent fuel and high temperature molten salt at ACPF had been developed in cooperation with Applied Photonics Ltd. FO-LIBS has some advantages as followings: the detectable plasma light wavelength range is not limited by the optical properties of the thick lead-glass shield window and the potential risk of laser damage to the lead-glass shield window is not considered. The remote LIBS instrument had been installed at ACPF and then the feasibility study for monitoring actinide elements such as uranium, plutonium, and curium in process materials has been carried out. (authors)« less

Crystallographic phase induced electro-optic properties of nanorod blend nematic liquid crystal.

PubMed

Kundu, Sudarshan; Hill, Jonathan P; Richards, Gary J; Ariga, Katsuhiko; Khan, Ali Hossain; Thupakula, Umamahesh; Acharya, Somobrata

2011-09-01

Ultrasmall ZnS or PbS nanorods encapsulated in fluid-like soft organic surfactants show excellent miscibility in the nematic liquid crystal (LC ZLI-4792) host resulting in a novel soft matter type blend with enhanced electro-optic properties. The ultranarrow ZnS rods are of wurtzite phase and possess a chemical bipolarity and a net dipole moment. The centrosymmetric ultranarrow PbS rods possess a finite size and shape dependent inherent dipole moment despite their cubic rock-salt structure. When an electric field is applied, the blend aligns along the direction of the field producing a local unidirectional orientation of the rods and LC directors, and defining a unique axis for the system. The local ordering significantly affects the global ordering of the blend allowing a more rapid response of the electro-optic properties. The degree and switching speed of the blends depend upon the magnitude of dipole moments present in the dopant nanorods. We show how a non-mesogenic element designed with preferential crystallographic phase can be introduced within a LC for improvement of the switching properties of the LC blend. These types of unique blends are a model for fundamental conceptual advances in general understanding of interaction behaviour leading consequently to a significant technological advancement for superior device fabrication.

Quantitative analysis with advanced compensated polarized light microscopy on wavelength dependence of linear birefringence of single crystals causing arthritis

NASA Astrophysics Data System (ADS)

Takanabe, Akifumi; Tanaka, Masahito; Taniguchi, Atsuo; Yamanaka, Hisashi; Asahi, Toru

2014-07-01

To improve our ability to identify single crystals causing arthritis, we have developed a practical measurement system of polarized light microscopy called advanced compensated polarized light microscopy (A-CPLM). The A-CPLM system is constructed by employing a conventional phase retardation plate, an optical fibre and a charge-coupled device spectrometer in a polarized light microscope. We applied the A-CPLM system to measure linear birefringence (LB) in the visible region, which is an optical anisotropic property, for tiny single crystals causing arthritis, i.e. monosodium urate monohydrate (MSUM) and calcium pyrophosphate dihydrate (CPPD). The A-CPLM system performance was evaluated by comparing the obtained experimental data using the A-CPLM system with (i) literature data for a standard sample, MgF2, and (ii) experimental data obtained using an established optical method, high-accuracy universal polarimeter, for the MSUM. The A-CPLM system was found to be applicable for measuring the LB spectra of the single crystals of MSUM and CPPD, which cause arthritis, in the visible regions. We quantitatively reveal the large difference in LB between MSUM and CPPD crystals. These results demonstrate the usefulness of the A-CPLM system for distinguishing the crystals causing arthritis.

Multiplexing electro-optic architectures for advanced aircraft integrated flight control systems

NASA Technical Reports Server (NTRS)

Seal, D. W.

1989-01-01

This report describes the results of a 10 month program sponsored by NASA. The objective of this program was to evaluate various optical sensor modulation technologies and to design an optimal Electro-Optic Architecture (EOA) for servicing remote clusters of sensors and actuators in advanced aircraft flight control systems. The EOA's supply optical power to remote sensors and actuators, process the modulated optical signals returned from the sensors, and produce conditioned electrical signals acceptable for use by a digital flight control computer or Vehicle Management System (VMS) computer. This study was part of a multi-year initiative under the Fiber Optic Control System Integration (FOCSI) program to design, develop, and test a totally integrated fiber optic flight/propulsion control system for application to advanced aircraft. Unlike earlier FOCSI studies, this program concentrated on the design of the EOA interface rather than the optical transducer technology itself.

Recent progress in tissue optical clearing

PubMed Central

Zhu, Dan; Larin, Kirill V; Luo, Qingming; Tuchin, Valery V

2013-01-01

Tissue optical clearing technique provides a prospective solution for the application of advanced optical methods in life sciences. This paper gives a review of recent developments in tissue optical clearing techniques. The physical, molecular and physiological mechanisms of tissue optical clearing are overviewed and discussed. Various methods for enhancing penetration of optical-clearing agents into tissue, such as physical methods, chemical-penetration enhancers and combination of physical and chemical methods are introduced. Combining the tissue optical clearing technique with advanced microscopy image or labeling technique, applications for 3D microstructure of whole tissues such as brain and central nervous system with unprecedented resolution are demonstrated. Moreover, the difference in diffusion and/or clearing ability of selected agents in healthy versus pathological tissues can provide a highly sensitive indicator of the tissue health/pathology condition. Finally, recent advances in optical clearing of soft or hard tissue for in vivo imaging and phototherapy are introduced. PMID:24348874

Enhanced intercarrier interference mitigation based on encoded bit-sequence distribution inside optical superchannels

NASA Astrophysics Data System (ADS)

Torres, Jhon James Granada; Soto, Ana María Cárdenas; González, Neil Guerrero

2016-10-01

In the context of gridless optical multicarrier systems, we propose a method for intercarrier interference (ICI) mitigation which allows bit error correction in scenarios of nonspectral flatness between the subcarriers composing the multicarrier system and sub-Nyquist carrier spacing. We propose a hybrid ICI mitigation technique which exploits the advantages of signal equalization at both levels: the physical level for any digital and analog pulse shaping, and the bit-data level and its ability to incorporate advanced correcting codes. The concatenation of these two complementary techniques consists of a nondata-aided equalizer applied to each optical subcarrier, and a hard-decision forward error correction applied to the sequence of bits distributed along the optical subcarriers regardless of prior subchannel quality assessment as performed in orthogonal frequency-division multiplexing modulations for the implementation of the bit-loading technique. The impact of the ICI is systematically evaluated in terms of bit-error-rate as a function of the carrier frequency spacing and the roll-off factor of the digital pulse-shaping filter for a simulated 3×32-Gbaud single-polarization quadrature phase shift keying Nyquist-wavelength division multiplexing system. After the ICI mitigation, a back-to-back error-free decoding was obtained for sub-Nyquist carrier spacings of 28.5 and 30 GHz and roll-off values of 0.1 and 0.4, respectively.

Precision molding of advanced glass optics: innovative production technology for lens arrays and free form optics

NASA Astrophysics Data System (ADS)

Pongs, Guido; Bresseler, Bernd; Bergs, Thomas; Menke, Gert

2012-10-01

Today isothermal precision molding of imaging glass optics has become a widely applied and integrated production technology in the optical industry. Especially in consumer electronics (e.g. digital cameras, mobile phones, Blu-ray) a lot of optical systems contain rotationally symmetrical aspherical lenses produced by precision glass molding. But due to higher demands on complexity and miniaturization of optical elements the established process chain for precision glass molding is not sufficient enough. Wafer based molding processes for glass optics manufacturing become more and more interesting for mobile phone applications. Also cylindrical lens arrays can be used in high power laser systems. The usage of unsymmetrical free-form optics allows an increase of efficiency in optical laser systems. Aixtooling is working on different aspects in the fields of mold manufacturing technologies and molding processes for extremely high complex optical components. In terms of array molding technologies, Aixtooling has developed a manufacturing technology for the ultra-precision machining of carbide molds together with European partners. The development covers the machining of multi lens arrays as well as cylindrical lens arrays. The biggest challenge is the molding of complex free-form optics having no symmetrical axis. A comprehensive CAD/CAM data management along the entire process chain is essential to reach high accuracies on the molded lenses. Within a national funded project Aixtooling is working on a consistent data handling procedure in the process chain for precision molding of free-form optics.

Bandgap engineering of InGaAsP/InP laser structure by photo-absorption-induced point defects

NASA Astrophysics Data System (ADS)

Kaleem, Mohammad; Nazir, Sajid; Saqib, Nazar Abbas

2016-03-01

Integration of photonic components on the same photonic wafer permits future optical communication systems to be dense and advanced performance. This enables very fast information handling between photonic active components interconnected through passive optical low loss channels. We demonstrate the UV-Laser based Quantum Well Intermixing (QWI) procedure to engineer the band-gap of compressively strained InGaAsP/InP Quantum Well (QW) laser material. We achieved around 135nm of blue-shift by simply applying excimer laser (λ= 248nm). The under observation laser processed material also exhibits higher photoluminescence (PL) intensity. Encouraging experimental results indicate that this simple technique has the potential to produce photonic integrated devices and circuits.

Optofluidic Cell Selection from Complex Microbial Communities for Single-Genome Analysis

PubMed Central

Landry, Zachary C.; Giovanonni, Stephen J.; Quake, Stephen R.; Blainey, Paul C.

2013-01-01

Genetic analysis of single cells is emerging as a powerful approach for studies of heterogeneous cell populations. Indeed, the notion of homogeneous cell populations is receding as approaches to resolve genetic and phenotypic variation between single cells are applied throughout the life sciences. A key step in single-cell genomic analysis today is the physical isolation of individual cells from heterogeneous populations, particularly microbial populations, which often exhibit high diversity. Here, we detail the construction and use of instrumentation for optical trapping inside microfluidic devices to select individual cells for analysis by methods including nucleic acid sequencing. This approach has unique advantages for analyses of rare community members, cells with irregular morphologies, small quantity samples, and studies that employ advanced optical microscopy. PMID:24060116

Non-Intrusive Optical Diagnostic Methods for Flowfield Characterization

NASA Technical Reports Server (NTRS)

Tabibi, Bagher M.; Terrell, Charles A.; Spraggins, Darrell; Lee, Ja. H.; Weinstein, Leonard M.

1997-01-01

Non-intrusive optical diagnostic techniques such as Electron Beam Fluorescence (EBF), Laser-Induced Fluorescence (LIF), and Focusing Schlieren (FS) have been setup for high-speed flow characterization and large flowfield visualization, respectively. Fluorescence emission from the First Negative band of N2(+) with the (0,0) vibration transition (at lambda =391.44 nm) was obtained using the EBF technique and a quenching rate of N2(+)* molecules by argon gas was reported. A very high sensitivity FS system was built and applied in the High-Speed Flow Generator (HFG) at NASA LaRC. A LIF system is available at the Advanced Propulsion Laboratory (APL) on campus and a plume exhaust velocity measurement, measuring the Doppler shift from lambda = 728.7 nm of argon gas, is under way.

Spectrally encoded optical fibre sensor systems and their application in process control, environmental and structural monitoring

NASA Astrophysics Data System (ADS)

Willsch, Reinhardt; Ecke, Wolfgang; Schwotzer, Gunter

2005-09-01

Different types of advanced optical fibre sensor systems using similar spectral interrogation principles and potential low-cost polychromator optoelectronic signal processing instrumentation will be presented, and examples of their industrial application are demonstrated. These are such sensors as multimode fibre based humidity, temperature, and pressure sensors with extrinsic microoptical Fabry-Perot transducers for process control in gas industry, UV absorption evanescent field sensors for organic pollution monitoring in groundwater, and single mode fibre Bragg grating (FBG) multiplexed strain & vibration and temperature sensor networks for structural health monitoring applications in electric power facilities, aerospace, railways, geotechnical and civil engineering. Recent results of current investigations applying FBGs and microstructured fibres for chemical sensing will be discussed.

Optical Molecular Imaging for Diagnosing Intestinal Diseases

PubMed Central

Kim, Sang-Yeob

2013-01-01

Real-time visualization of the molecular signature of cells can be achieved with advanced targeted imaging techniques using molecular probes and fluorescence endoscopy. This molecular optical imaging in gastrointestinal endoscopy is promising for improving the detection of neoplastic lesions, their characterization for patient stratification, and the assessment of their response to molecular targeted therapy and radiotherapy. In inflammatory bowel disease, this method can be used to detect dysplasia in the presence of background inflammation and to visualize inflammatory molecular targets for assessing disease severity and prognosis. Several preclinical and clinical trials have applied this method in endoscopy; however, this field has just started to evolve. Hence, many problems have yet to be solved to enable the clinical application of this novel method. PMID:24340254

Review of advanced imaging techniques

PubMed Central

Chen, Yu; Liang, Chia-Pin; Liu, Yang; Fischer, Andrew H.; Parwani, Anil V.; Pantanowitz, Liron

2012-01-01

Pathology informatics encompasses digital imaging and related applications. Several specialized microscopy techniques have emerged which permit the acquisition of digital images (“optical biopsies”) at high resolution. Coupled with fiber-optic and micro-optic components, some of these imaging techniques (e.g., optical coherence tomography) are now integrated with a wide range of imaging devices such as endoscopes, laparoscopes, catheters, and needles that enable imaging inside the body. These advanced imaging modalities have exciting diagnostic potential and introduce new opportunities in pathology. Therefore, it is important that pathology informaticists understand these advanced imaging techniques and the impact they have on pathology. This paper reviews several recently developed microscopic techniques, including diffraction-limited methods (e.g., confocal microscopy, 2-photon microscopy, 4Pi microscopy, and spatially modulated illumination microscopy) and subdiffraction techniques (e.g., photoactivated localization microscopy, stochastic optical reconstruction microscopy, and stimulated emission depletion microscopy). This article serves as a primer for pathology informaticists, highlighting the fundamentals and applications of advanced optical imaging techniques. PMID:22754737

Active x-ray optics for Generation-X, the next high resolution x-ray observatory

NASA Astrophysics Data System (ADS)

Elvis, Martin; Brissenden, R. J.; Fabbiano, G.; Schwartz, D. A.; Reid, P.; Podgorski, W.; Eisenhower, M.; Juda, M.; Phillips, J.; Cohen, L.; Wolk, S.

2006-06-01

X-rays provide one of the few bands through which we can study the epoch of reionization, when the first galaxies, black holes and stars were born. To reach the sensitivity required to image these first discrete objects in the universe needs a major advance in X-ray optics. Generation-X (Gen-X) is currently the only X-ray astronomy mission concept that addresses this goal. Gen-X aims to improve substantially on the Chandra angular resolution and to do so with substantially larger effective area. These two goals can only be met if a mirror technology can be developed that yields high angular resolution at much lower mass/unit area than the Chandra optics, matching that of Constellation-X (Con-X). We describe an approach to this goal based on active X-ray optics that correct the mid-frequency departures from an ideal Wolter optic on-orbit. We concentrate on the problems of sensing figure errors, calculating the corrections required, and applying those corrections. The time needed to make this in-flight calibration is reasonable. A laboratory version of these optics has already been developed by others and is successfully operating at synchrotron light sources. With only a moderate investment in these optics the goals of Gen-X resolution can be realized.

Polarization in Nanophotonics

NASA Astrophysics Data System (ADS)

Mueller, Jan Philipp Balthasar

In the last three or so decades, optical scientists have begun to capitalize in earnest on the advances in nanofabrication that is owed to the explosive rise of miniaturized semiconductor electronics. The resulting field, nanophotonics, has opened a vast design space for applied researchers and required revisiting some of the oldest problems and assumptions of optical physics. Polarization, meaning, in the context of light, the direction of oscillation of the electromagnetic field in space, is a particularly malleable property of light that can be used to shape and direct wave fronts, to measure and control light-matter interactions, and to encode information. It remains an underexplored and underutilized feature of nature, though the new methods of nanophotonics can harness its potential to a much greater extent than any previous optical technology platform. This thesis explores some aspects of the role light's polarization plays at the interface of optics and nanotechnology. In particular, it will touch upon the way polarization may be used to control the generation of optical nearfields, how the polarization structure of evanescent waves leads to unusual optical forces, and how nanoscale polarization-transformations enable a new class of polarization-sensitive optical elements. It will also show how nanophotonics may address the problem of measuring polarization based on a new polarimeter architecture.

Soft optics in intelligent optical networks

NASA Astrophysics Data System (ADS)

Shue, Chikong; Cao, Yang

2001-10-01

In addition to the recent advances in Hard-optics that pushes the optical transmission speed, distance, wave density and optical switching capacity, Soft-optics provides the necessary intelligence and control software that reduces operational costs, increase efficiency, and enhances revenue generating services by automating optimal optical circuit placement and restoration, and enabling value-added new services like Optical VPN. This paper describes the advances in 1) Overall Hard-optics and Soft-optics 2) Layered hierarchy of Soft-optics 3) Component of Soft-optics, including hard-optics drivers, Management Soft-optics, Routing Soft-optics and System Soft-optics 4) Key component of Routing and System Soft-optics, namely optical routing and signaling (including UNI/NNI and GMPLS signaling). In summary, the soft-optics on a new generation of OXC's enables Intelligent Optical Networks to provide just-in-time service delivery and fast restoration, and real-time capacity management that eliminates stranded bandwidth. It reduces operational costs and provides new revenue opportunities.

Engineering design in the primary school: applying stem concepts to build an optical instrument

NASA Astrophysics Data System (ADS)

King, Donna; English, Lyn D.

2016-12-01

Internationally there is a need for research that focuses on STEM (Science, Technology, Engineering and Mathematics) education to equip students with the skills needed for a rapidly changing future. One way to do this is through designing engineering activities that reflect real-world problems and contextualise students' learning of STEM concepts. As such, this study examined the learning that occurred when fifth-grade students completed an optical engineering activity using an iterative engineering design model. Through a qualitative methodology using a case study design, we analysed multiple data sources including students' design sketches from eight focus groups. Three key findings emerged: first, the collaborative process of the first design sketch enabled students to apply core STEM concepts to model construction; second, during the construction stage students used experimentation for the positioning of lenses, mirrors and tubes resulting in a simpler 'working' model; and third, the redesign process enabled students to apply structural changes to their design. The engineering design model was useful for structuring stages of design, construction and redesign; however, we suggest a more flexible approach for advanced applications of STEM concepts in the future.

Wireless infrared communications for space and terrestrial applications

NASA Technical Reports Server (NTRS)

Crimmins, James W.

1993-01-01

Voice and data communications via wireless (and fiberless) optical means has been commonplace for many years. However, continuous advances in optoelectronics and microelectronics have resulted in significant advances in wireless optical communications over the last decade. Wilton has specialized in diffuse infrared voice and data communications since 1979. In 1986, NASA Johnson Space Center invited Wilton to apply its wireless telecommunications and factory floor technology to astronaut voice communications aboard the shuttle. In September, 1988 a special infrared voice communications system flew aboard a 'Discovery' Shuttle mission as a flight experiment. Since then the technology has been further developed, resulting in a general purpose of 2Mbs wireless voice/data LAN which has been tested for a variety of applications including use aboard Spacelab. Funds for Wilton's wireless IR development were provided in part by NASA's Technology Utilization Office and by the NASA Small Business Innovative Research Program. As a consequence, Wilton's commercial product capability has been significantly enhanced to include diffuse infrared wireless LAN's as well as wireless infrared telecommunication systems for voice and data.

Mueller matrix signature in advanced fluorescence microscopy imaging

NASA Astrophysics Data System (ADS)

Mazumder, Nirmal; Qiu, Jianjun; Kao, Fu-Jen; Diaspro, Alberto

2017-02-01

We have demonstrated the measurement and characterization of the polarization properties of a fluorescence signal using four-channel photon counting based Stokes-Mueller polarization microscopy. Thus, Lu-Chipman decomposition was applied to extract the critical polarization properties such as depolarization, linear retardance and the optical rotation of collagen type I fiber. We observed the spatial distribution of anisotropic and helical molecules of collagen from the reconstructed 2D Mueller images based on the fluorescence signal in a pixel-by-pixel manner.

Diagram of Zeolite Crystals

NASA Technical Reports Server (NTRS)

2003-01-01

The Center for Advanced Microgravity Materials Processing (CAMMP) in Cambridge, MA, a NASA-sponsored Commercial Space Center, is working to improve zeolite materials for storing hydrogen fuel. CAMMP is also applying zeolites to detergents, optical cables, gas and vapor detection for environmental monitoring and control, and chemical production techniques that significantly reduce by-products that are hazardous to the environment. Depicted here is one of the many here complex geometric shapes which make them highly absorbent. Zeolite experiments have also been conducted aboard the International Space Station

Material Science

NASA Image and Video Library

2003-01-12

The Center for Advanced Microgravity Materials Processing (CAMMP), a NASA-sponsored Research Partnership Center, is working to improve zeolite materials for storing hydrogen fuel. CAMMP is also applying zeolites to detergents, optical cables, gas and vapor detection for environmental monitoring and control, and chemical production techniques that significantly reduce by-products that are hazardous to the environment. Shown here are zeolite crystals (top) grown in a ground control experiment and grown in microgravity on the USML-2 mission (bottom). Zeolite experiments have also been conducted aboard the International Space Station.

Material Science

NASA Image and Video Library

2003-01-12

The Center for Advanced Microgravity Materials Processing (CAMMP) in Cambridge, MA, a NASA-sponsored Commercial Space Center, is working to improve zeolite materials for storing hydrogen fuel. CAMMP is also applying zeolites to detergents, optical cables, gas and vapor detection for environmental monitoring and control, and chemical production techniques that significantly reduce by-products that are hazardous to the environment. Depicted here is one of the many here complex geometric shapes which make them highly absorbent. Zeolite experiments have also been conducted aboard the International Space Station

Microfocusing of the FERMI@Elettra FEL beam with a K-B active optics system: Spot size predictions by application of the WISE code

NASA Astrophysics Data System (ADS)

Raimondi, L.; Svetina, C.; Mahne, N.; Cocco, D.; Abrami, A.; De Marco, M.; Fava, C.; Gerusina, S.; Gobessi, R.; Capotondi, F.; Pedersoli, E.; Kiskinova, M.; De Ninno, G.; Zeitoun, P.; Dovillaire, G.; Lambert, G.; Boutu, W.; Merdji, H.; Gonzalez, A. I.; Gauthier, D.; Zangrando, M.

2013-05-01

FERMI@Elettra, the first seeded EUV-SXR free electron laser (FEL) facility located at Elettra Sincrotrone Trieste has been conceived to provide very short (10-100 fs) pulses with ultrahigh peak brightness and wavelengths from 100 nm to 4 nm. A section fully dedicated to the photon transport and analysis diagnostics, named PADReS, has already been installed and commissioned. Three of the beamlines, EIS-TIMEX, DiProI and LDM, installed after the PADReS section, are in advanced commissioning state and will accept the first users in December 2012. These beam lines employ active X-ray optics in order to focus the FEL beam as well as to perform a controlled beam-shaping at focus. Starting from mirror surface metrology characterization, it is difficult to predict the focal spot shape applying only methods based on geometrical optics such as the ray tracing. Within the geometrical optics approach one cannot take into account the diffraction effect from the optics edges, i.e. the aperture diffraction, and the impact of different surface spatial wavelengths to the spot size degradation. Both these effects are strongly dependent on the photon beam energy and mirror incident angles. We employed a method based on physical optics, which applies the Huygens-Fresnel principle to reflection (on which the WISE code is based). In this work we report the results of the first measurements of the focal spot in the DiProI beamline end-station and compare them to the predictions computed with Shadow code and WISE code, starting from the mirror surface profile characterization.

Topological study of nanomaterials using surface-enhanced ellipsometric contrast microscopy (SEEC)

NASA Astrophysics Data System (ADS)

Muckenhirn, Sylvain

2016-03-01

Innovations in nanotechnology are empowering scientists to deepen their understanding of physical, chemical and biological mechanisms. Powerful and precise characterization systems are essential to meet researchers' requirements. SEEC (Surface Enhanced Ellipsometric Contrast) microscopy is an innovative advanced optical technique based on ellipsometric and interference fringes of Fizeau principles. This technique offers live and label-free topographic imaging of organic, inorganic and biological samples with high Z resolution (down to 0.1nm thickness), and enhanced X-Y detection limit (down to 1.5nm width). This technique has been successfully applied to the study of nanometric films and structures, biological layers, and nano-objects. We applied SEEC technology to different applications explored below.

SINET3: advanced optical and IP hybrid network

NASA Astrophysics Data System (ADS)

Urushidani, Shigeo

2007-11-01

This paper introduces the new Japanese academic backbone network called SINET3, which has been in full-scale operation since June 2007. SINET3 provides a wide variety of network services, such as multi-layer transfer, enriched VPN, enhanced QoS, and layer-1 bandwidth on demand (BoD) services to create an innovative and prolific science infrastructure for more than 700 universities and research institutions. The network applies an advanced hybrid network architecture composed of 75 layer-1 switches and 12 high-performance IP routers to accommodate such diversified services in a single network platform, and provides sufficient bandwidth using Japan's first STM256 (40 Gbps) lines. The network adopts lots of the latest networking technologies, such as next-generation SDH (VCAT/GFP/LCAS), GMPLS, advanced MPLS, and logical-router technologies, for high network convergence, flexible resource assignment, and high service availability. This paper covers the network services, network design, and networking technologies of SINET3.

Preliminary Experimental Investigation of Quasi Achromat scheme at Advanced Photon Source

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sun, Yipeng; Shang, Hairong

Next generation storage rings require weaker dipolemagnets and stronger quadrupole focusing to achieve very low emittance. To suppress the geometric and chromatic optics aberrations introduced by the strong sextupoles, achromat and quasi achromat schemes are applied in the lattice design to improve the beam dynamics performance. In this paper, some preliminary experimental investigation of the quasi achromat scheme at the Advanced Photon Source (APS) are presented. Three different operation lattices are compared on their beam dynamics performance. Although none of these operation lattices achieve ideal quasi achromat condition, they have certain relevant features. It is observed that fewer resonances aremore » present in the nominal operation lattice which is most close to quasi achromat required conditions.« less

Advanced magneto-optical microscopy: Imaging from picoseconds to centimeters - imaging spin waves and temperature distributions (invited)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Urs, Necdet Onur; Mozooni, Babak; Kustov, Mikhail

2016-05-15

Recent developments in the observation of magnetic domains and domain walls by wide-field optical microscopy based on the magneto-optical Kerr, Faraday, Voigt, and Gradient effect are reviewed. Emphasis is given to the existence of higher order magneto-optical effects for advanced magnetic imaging. Fundamental concepts and advances in methodology are discussed that allow for imaging of magnetic domains on various length and time scales. Time-resolved imaging of electric field induced domain wall rotation is shown. Visualization of magnetization dynamics down to picosecond temporal resolution for the imaging of spin-waves and magneto-optical multi-effect domain imaging techniques for obtaining vectorial information are demonstrated.more » Beyond conventional domain imaging, the use of a magneto-optical indicator technique for local temperature sensing is shown.« less

Liquid lens: advances in adaptive optics

NASA Astrophysics Data System (ADS)

Casey, Shawn Patrick

2010-12-01

'Liquid lens' technologies promise significant advancements in machine vision and optical communications systems. Adaptations for machine vision, human vision correction, and optical communications are used to exemplify the versatile nature of this technology. Utilization of liquid lens elements allows the cost effective implementation of optical velocity measurement. The project consists of a custom image processor, camera, and interface. The images are passed into customized pattern recognition and optical character recognition algorithms. A single camera would be used for both speed detection and object recognition.

Spectral-domain optical coherence tomography for endoscopic imaging

NASA Astrophysics Data System (ADS)

Chen, Xiaodong; Li, Qiao; Li, Wanhui; Wang, Yi; Yu, Daoyin

2007-02-01

Optical coherence tomography (OCT) is an emerging cross-sectional imaging technology. It uses broadband light sources to achieve axial image resolutions on the few micron scale. OCT is widely applied to medical imaging, it can get cross-sectional image of bio-tissue (transparent and turbid) with non-invasion and non-touch. In this paper, the principle of OCT is presented and the crucial parameters of the system are discussed in theory. With analysis of different methods and medical endoscopic system's feature, a design which combines the spectral domain OCT (SDOCT) technique and endoscopy is put forward. SDOCT provides direct access to the spectrum of the optical signal. It is shown to provide higher imaging speed when compared to time domain OCT. At the meantime, a novel OCT probe which uses advanced micromotor to drive reflecting prism is designed according to alimentary tract endoscopic feature. A simple optical coherence tomography system has been developed based on a fiber-based Michelson interferometer and spectrometer. An experiment which uses motor to drive prism to realize rotating imaging is done. Images obtained with this spectral interferometer are presented. The results verify the feasibility of endoscopic optical coherence tomography system with rotating scan.

Theory of plasmonic effects in nonlinear optics: the case of graphene

NASA Astrophysics Data System (ADS)

Rostami, Habib; Katsnelson, Mikhail I.; Polini, Marco; Mikhail I. Katsnelson Collaboration; Habib Rostami; Marco Polini Collaboration

The nonlinear optical properties of two-dimensional electronic systems are beginning to attract considerable interest both in the theoretical and experimental sectors. Recent experiments on the nonlinear optical properties of graphene reveal considerably strong third harmonic generation and four-wave mixing of this single-atomic-layer electronic system. We develop a large-N theory of electron-electron interaction corrections to multi-legged Feynman diagrams describing second- and third-order nonlinear response functions. Our theory is completely general and is useful to understand all second- and third-order nonlinear effects, including harmonic generation, wave mixing, and photon drag. We apply our theoretical framework to the case of graphene, by carrying out microscopic calculations of the second- and third-order nonlinear response functions of an interacting two-dimensional gas of massless Dirac fermions. We compare our results with recent measurements, where all-optical launching of graphene plasmons has been achieved. This work was supported by Fondazione Istituto Italiano di Tecnologia, the European Union's Horizon 2020 research and innovation programme under Grant agreement No. 696656 GrapheneCore, and the ERC Advanced Grant 338957 FEMTO/NANO (M.I.K.).

Specialized project in biophotonics

NASA Astrophysics Data System (ADS)

Garcia Martin, Agueda L.; Sastriques-Silva, Pedro O.; Martinez-Fundora, Julia N.; Augier Calderin, Angel G.; Lopez-Cepero, Xonia

2000-06-01

As science advances, it is more evident the necessity of a health interdisciplinary approach in Medicine. In the case of medical applications of light, the knowledge of the use of dispositives, equipment, diagnostic and treatment means, as well as the bases for the use of this update technologies is required. At the present moment, the outstanding work of specialized professionals of different profiles requires personnel with high professional formation in keeping with the latest trends in science and technology. The authors present here an Specialized Project in Biophotonics, with the aim of increasing the professional preparation of university graduates with an ample profile--physicists and engineers--who work in Biomedical Optics, thus contributing to the specialized formation of medic and paramedic personnel. The course is structured into six-subject-modules and into two phases. As to the basic professional formation, each one attending this course, will select between two variants of the Basic Formation Postgraduate Course: Anatomy and Physiology, Physical Bioenergetics, Clinic Bioenergetics; or Physics in Medicine, Optics and Applied Information Theory, depending on the student's professional profile. In the second phase, the General Formation Postgraduate Course: Biomedical Optics, Optical Bioenergetics and Laser in Medicine.

Compensation of X-ray mirror shape-errors using refractive optics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sawhney, Kawal, E-mail: Kawal.sawhney@diamond.ac.uk; Laundy, David; Pape, Ian

2016-08-01

Focusing of X-rays to nanometre scale focal spots requires high precision X-ray optics. For nano-focusing mirrors, height errors in the mirror surface retard or advance the X-ray wavefront and after propagation to the focal plane, this distortion of the wavefront causes blurring of the focus resulting in a limit on the spatial resolution. We describe here the implementation of a method for correcting the wavefront that is applied before a focusing mirror using custom-designed refracting structures which locally cancel out the wavefront distortion from the mirror. We demonstrate in measurements on a synchrotron radiation beamline a reduction in the sizemore » of the focal spot of a characterized test mirror by a factor of greater than 10 times. This technique could be used to correct existing synchrotron beamline focusing and nanofocusing optics providing a highly stable wavefront with low distortion for obtaining smaller focus sizes. This method could also correct multilayer or focusing crystal optics allowing larger numerical apertures to be used in order to reduce the diffraction limited focal spot size.« less

Design and Performance Evaluation of Sensors and Actuators for Advanced Optical Systems

NASA Technical Reports Server (NTRS)

Clark, Natalie

2011-01-01

Current state-of-the-art commercial sensors and actuators do not meet many of NASA s next generation spacecraft and instrument needs. Nor do they satisfy the DoD needs for satellite missions, especially micro/nano satellite missions. In an effort to develop advanced optical devices and instruments that meet mission requirements, NASA Langley recently completed construction of a new cleanroom housing equipment capable of fabricating high performance active optic and adaptive optic technologies including deformable mirrors, reconfigurable lenses (both refractive and diffractive), spectrometers, spectro-polarimeters, tunable filters and many other active optic devices. In addition to performance, these advanced optic technologies offer advantages in speed, size, weight, power consumption, and radiation tolerance. The active optic devices described in this paper rely on birefringent liquid crystal materials to alter either the phase or the polarization of the incoming light. Design considerations and performance evaluation results for various NASA applications are presented. Applications presented will include large space telescopes, optical communications, spacecraft windows, coronagraphs, and star trackers. Keywords: Photonics, Adaptive Optics, Tunable Filters, MEMs., MOEMs, Coronagraph, Star Tracker

EDITORIAL: Changes to the journal Changes to the journal

NASA Astrophysics Data System (ADS)

Zheludev, Nikolay I.

2010-01-01

It is a privilege to be Editor-in-Chief of Journal of Optics at this exciting time when the use of light spearheads the development of new technologies in telecommunications, green energy, manufacturing, medicine and defence, just to mention a few. These technological advances, seen by many as the next photonic technological revolution, are underpinned by fundamental and applied research in the following key directions: Nanophotonics and plasmonics Metamaterials and structured photonic materials Nonlinear and ultrafast optics Photonics at the life science interface Information and communication optics Integrated optics systems and devices Material processing with light Propagation, diffraction and scattering This is where Journal of Optics focuses its attention. This editorial marks the first issue of the journal published under the abbreviated name (shortened from Journal of Optics A: Pure and Applied Optics). The name change is just one of a series of changes introduced in the last year, along with the 8 subject sections listed above and the appointment of Section Editors. With the name change, we will also update the look of the journal by introducing colour cover images which will feature some of the most exciting research in the journal. We have retained many of the journal's original selling points: we are found in thousands of libraries around the world, and will continue our policy of free web access to all papers for 30 days after publication, ensuring broad and unrestricted dissemination of your research results. We will also continue our strong and well respected special issue and topical review programmes and we are always grateful to receive new suggestions for special issues or review articles. Along with the Editorial Board, I would like to thank the authors, referees and readers who have contributed to the success of Journal of Optics. The increasing quality and visibility of the journal, as demonstrated by the dramatic increase in its impact factor in recent years, make it a prime destination for research papers across the field of optics. So, if you're not already part of our community, we hope you'll join us soon by submitting your next research paper to Journal of Optics.

Alignment error of mirror modules of advanced telescope for high-energy astrophysics due to wavefront aberrations

NASA Astrophysics Data System (ADS)

Zocchi, Fabio E.

2017-10-01

One of the approaches that is being tested for the integration of the mirror modules of the advanced telescope for high-energy astrophysics x-ray mission of the European Space Agency consists in aligning each module on an optical bench operated at an ultraviolet wavelength. The mirror module is illuminated by a plane wave and, in order to overcome diffraction effects, the centroid of the image produced by the module is used as a reference to assess the accuracy of the optical alignment of the mirror module itself. Among other sources of uncertainty, the wave-front error of the plane wave also introduces an error in the position of the centroid, thus affecting the quality of the mirror module alignment. The power spectral density of the position of the point spread function centroid is here derived from the power spectral density of the wave-front error of the plane wave in the framework of the scalar theory of Fourier diffraction. This allows the defining of a specification on the collimator quality used for generating the plane wave starting from the contribution to the error budget allocated for the uncertainty of the centroid position. The theory generally applies whenever Fourier diffraction is a valid approximation, in which case the obtained result is identical to that derived by geometrical optics considerations.

Development of advanced seal verification

NASA Technical Reports Server (NTRS)

Workman, Gary L.; Kosten, Susan E.; Abushagur, Mustafa A.

1992-01-01

The purpose of this research is to develop a technique to monitor and insure seal integrity with a sensor that has no active elements to burn-out during a long duration activity, such as a leakage test or especially during a mission in space. The original concept proposed is that by implementing fiber optic sensors, changes in the integrity of a seal can be monitored in real time and at no time should the optical fiber sensor fail. The electrical components which provide optical excitation and detection through the fiber are not part of the seal; hence, if these electrical components fail, they can be easily changed without breaking the seal. The optical connections required for the concept to work does present a functional problem to work out. The utility of the optical fiber sensor for seal monitoring should be general enough that the degradation of a seal can be determined before catastrophic failure occurs and appropriate action taken. Two parallel efforts were performed in determining the feasibility of using optical fiber sensors for seal verification. In one study, research on interferometric measurements of the mechanical response of the optical fiber sensors to seal integrity was studied. In a second study, the implementation of the optical fiber to a typical vacuum chamber was implemented and feasibility studies on microbend experiments in the vacuum chamber were performed. Also, an attempt was made to quantify the amount of pressure actually being applied to the optical fiber using finite element analysis software by Algor.

A Next-Generation Hard X-Ray Nanoprobe Beamline for In Situ Studies of Energy Materials and Devices

NASA Astrophysics Data System (ADS)

Maser, Jörg; Lai, Barry; Buonassisi, Tonio; Cai, Zhonghou; Chen, Si; Finney, Lydia; Gleber, Sophie-Charlotte; Jacobsen, Chris; Preissner, Curt; Roehrig, Chris; Rose, Volker; Shu, Deming; Vine, David; Vogt, Stefan

2014-01-01

The Advanced Photon Source is developing a suite of new X-ray beamlines to study materials and devices across many length scales and under real conditions. One of the flagship beamlines of the APS upgrade is the In Situ Nanoprobe (ISN) beamline, which will provide in situ and operando characterization of advanced energy materials and devices under varying temperatures, gas ambients, and applied fields, at previously unavailable spatial resolution and throughput. Examples of materials systems include inorganic and organic photovoltaic systems, advanced battery systems, fuel cell components, nanoelectronic devices, advanced building materials and other scientifically and technologically relevant systems. To characterize these systems at very high spatial resolution and trace sensitivity, the ISN will use both nanofocusing mirrors and diffractive optics to achieve spots sizes as small as 20 nm. Nanofocusing mirrors in Kirkpatrick-Baez geometry will provide several orders of magnitude increase in photon flux at a spatial resolution of 50 nm. Diffractive optics such as zone plates and/or multilayer Laue lenses will provide a highest spatial resolution of 20 nm. Coherent diffraction methods will be used to study even small specimen features with sub-10 nm relevant length scale. A high-throughput data acquisition system will be employed to significantly increase operations efficiency and usability of the instrument. The ISN will provide full spectroscopy capabilities to study the chemical state of most materials in the periodic table, and enable X-ray fluorescence tomography. In situ electrical characterization will enable operando studies of energy and electronic devices such as photovoltaic systems and batteries. We describe the optical concept for the ISN beamline, the technical design, and the approach for enabling a broad variety of in situ studies. We furthermore discuss the application of hard X-ray microscopy to study defects in multi-crystalline solar cells, one of the lines of inquiries for which the ISN is being developed.

Self-reported optometric practise patterns in age-related macular degeneration.

PubMed

Ly, Angelica; Nivison-Smith, Lisa; Zangerl, Barbara; Assaad, Nagi; Kalloniatis, Michael

2017-11-01

The use of advanced imaging in clinical practice is emerging and the use of this technology by optometrists in assessing patients with age-related macular degeneration is of interest. Therefore, this study explored contemporary, self-reported patterns of practice regarding age-related macular degeneration diagnosis and management using a cross-sectional survey of optometrists in Australia and New Zealand. Practising optometrists were surveyed on four key areas, namely, demographics, clinical skills and experience, assessment and management of age-related macular degeneration. Questions pertaining to self-rated competency, knowledge and attitudes used a five-point Likert scale. Completed responses were received from 127 and 87 practising optometrists in Australia and New Zealand, respectively. Advanced imaging showed greater variation in service delivery than traditional techniques (such as slitlamp funduscopy) and trended toward optical coherence tomography, which was routinely performed in age-related macular degeneration by 49 per cent of respondents. Optical coherence tomography was also associated with higher self-rated competency, knowledge and perceived relevance to practice than other modalities. Most respondents (93 per cent) indicated that they regularly applied patient symptoms, case history, visual function results and signs from traditional testing, when queried about their management of patients with age-related macular degeneration. Over half (63 per cent) also considered advanced imaging, while 31 per cent additionally considered all of these as well as the disease stage and clinical guidelines. Contrary to the evidence base, 68 and 34 per cent rated nutritional supplements as highly relevant or relevant in early age-related macular degeneration and normal aging changes, respectively. These results highlight the emergence of multimodal and advanced imaging (especially optical coherence tomography) in the assessment of age-related macular degeneration by optometrists. Clinically significant variations in self-rated test competency and the understanding regarding nutritional supplements for different stages of age-related macular degeneration suggest that further work to up-skill optometrists may be required. © 2017 Optometry Australia.

Characterization and compensation of thermo-elastic instability of SWARM optical bench on micro Advanced Stellar Compass attitude observations

NASA Astrophysics Data System (ADS)

Herceg, M.; Jørgensen, P. S.; Jørgensen, J. L.

2017-08-01

Launched into orbit on November 22, 2013, the Swarm constellation of three satellites precisely measures magnetic signal of the Earth. To ensure the high accuracy of magnetic observation by vector magnetometer (VFM), its inertial attitude is precisely determined by μASC (micro Advanced Stellar Compass). Each of the three Swarm satellites is equipped with three μASC Camera Head Units (CHU) mounted on a common optical bench (OB), which has a purpose of transference of the attitude from the star trackers to the magnetometer measurements. Although substantial pre-launch analyses were made to maximize thermal and mechanical stability of the OB, significant signal with thermal signature is discovered when comparing relative attitude between the three CHU's (Inter Boresight Angle, IBA). These misalignments between CHU's, and consequently geomagnetic reference frame, are found to be correlated with the period of angle between Swarm orbital plane and the Sun (ca. 267 days), which suggests sensitivity of optical bench system on temperature variation. In this paper, we investigate the propagation of thermal effects into the μASC attitude observations and demonstrate how thermally induced attitude variation can be predicted and corrected in the Swarm data processing. The results after applying thermal corrections show decrease in IBA RMS from 6.41 to 2.58″. The model significantly improves attitude determination which, after correction, meets the requirements of Swarm satellite mission. This study demonstrates the importance of the OB pre-launch analysis to ensure minimum thermal gradient on satellite optical system and therefore maximum attitude accuracy.

Measurement of time-varying displacement fields in cell culture for traction force optical coherence microscopy (Conference Presentation)

NASA Astrophysics Data System (ADS)

Mulligan, Jeffrey A.; Adie, Steven G.

2017-02-01

Mechanobiology is an emerging field which seeks to link mechanical forces and properties to the behaviors of cells and tissues in cancer, stem cell growth, and other processes. Traction force microscopy (TFM) is an imaging technique that enables the study of traction forces exerted by cells on their environment to migrate as well as sense and manipulate their surroundings. To date, TFM research has been performed using incoherent imaging modalities and, until recently, has been largely confined to the study of cell-induced tractions within two-dimensions using highly artificial and controlled environments. As the field of mechanobiology advances, and demand grows for research in physiologically relevant 3D culture and in vivo models, TFM will require imaging modalities that support such settings. Optical coherence microscopy (OCM) is an interferometric imaging modality which enables 3D cellular resolution imaging in highly scattering environments. Moreover, optical coherence elastography (OCE) enables the measurement of tissue mechanical properties. OCE relies on the principle of measuring material deformations in response to artificially applied stress. By extension, similar techniques can enable the measurement of cell-induced deformations, imaged with OCM. We propose traction force optical coherence microscopy (TF-OCM) as a natural extension and partner to existing OCM and OCE methods. We report the first use of OCM data and digital image correlation to track temporally varying displacement fields exhibited within a 3D culture setting. These results mark the first steps toward the realization of TF-OCM in 2D and 3D settings, bolstering OCM as a platform for advancing research in mechanobiology.

An optical lattice clock with accuracy and stability at the 10(-18) level.

PubMed

Bloom, B J; Nicholson, T L; Williams, J R; Campbell, S L; Bishof, M; Zhang, X; Zhang, W; Bromley, S L; Ye, J

2014-02-06

Progress in atomic, optical and quantum science has led to rapid improvements in atomic clocks. At the same time, atomic clock research has helped to advance the frontiers of science, affecting both fundamental and applied research. The ability to control quantum states of individual atoms and photons is central to quantum information science and precision measurement, and optical clocks based on single ions have achieved the lowest systematic uncertainty of any frequency standard. Although many-atom lattice clocks have shown advantages in measurement precision over trapped-ion clocks, their accuracy has remained 16 times worse. Here we demonstrate a many-atom system that achieves an accuracy of 6.4 × 10(-18), which is not only better than a single-ion-based clock, but also reduces the required measurement time by two orders of magnitude. By systematically evaluating all known sources of uncertainty, including in situ monitoring of the blackbody radiation environment, we improve the accuracy of optical lattice clocks by a factor of 22. This single clock has simultaneously achieved the best known performance in the key characteristics necessary for consideration as a primary standard-stability and accuracy. More stable and accurate atomic clocks will benefit a wide range of fields, such as the realization and distribution of SI units, the search for time variation of fundamental constants, clock-based geodesy and other precision tests of the fundamental laws of nature. This work also connects to the development of quantum sensors and many-body quantum state engineering (such as spin squeezing) to advance measurement precision beyond the standard quantum limit.

Interactive virtual optical laboratories

NASA Astrophysics Data System (ADS)

Liu, Xuan; Yang, Yi

2017-08-01

Laboratory experiences are essential for optics education. However, college students have limited access to advanced optical equipment that is generally expensive and complicated. Hence there is a need for innovative solutions to expose students to advanced optics laboratories. Here we describe a novel approach, interactive virtual optical laboratory (IVOL) that allows unlimited number of students to participate the lab session remotely through internet, to improve laboratory education in photonics. Although students are not physically conducting the experiment, IVOL is designed to engage students, by actively involving students in the decision making process throughout the experiment.

Bendable Focusing X-Ray Optics for the ALS and the LCLS/FEL: Design, Metrology, and Performance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yashchuk, V. V.; Yuan, S.; Baker, S.

2010-06-02

We review the recent development of bendable x-ray optics used for focusing of beams of soft and hard x-rays at the Advanced Light Source (ALS) at Lawrence Berkeley National Laboratory and at the Linac Coherent Light Source (LCLS) x-ray free electron laser (FEL) at the Stanford Linear Accelerator Center (SLAC) National Accelerator Laboratory. For simultaneous focusing in the tangential and sagittal directions, two elliptically cylindrical reflecting elements, a Kirkpatrick-Baez (KB) pair, are used. Because fabrication of elliptical surfaces is complicated, the cost of directly fabricated tangential elliptical cylinders is often prohibitive. Moreover, such optics cannot be easily readjusted for usemore » in multiple, different experimental arrangements, e.g. at different focal distances. This is in contrast to flat optics that are simpler to manufacture and easier to measure by conventional interferometry. The tangential figure of a flat substrate is changed by placing torques (couples) at each end. Depending on the applied couples, one can tune the shape close to a desired tangential cylinder, ellipse or parabola. We review the nature of the bending, requirements and approaches to the mechanical design, describe original optical and at-wavelength techniques for optimal tuning of bendable optics and alignment on the beamline, and provide beamline performance of the bendable optics used for sub-micro and nano focusing of soft x-rays.« less

Silicon nanowires: where mechanics and optics meet at the nanoscale.

PubMed

Ramos, Daniel; Gil-Santos, Eduardo; Malvar, Oscar; Llorens, Jose M; Pini, Valerio; San Paulo, Alvaro; Calleja, Montserrat; Tamayo, Javier

2013-12-06

Mechanical transducers based on nanowires promise revolutionary advances in biological sensing and force microscopy/spectroscopy. A crucial step is the development of simple and non-invasive techniques able to detect displacements with subpicometer sensitivity per unit bandwidth. Here, we design suspended tapered silicon nanowires supporting a range of optical resonances that confine and efficiently scatter light in the visible range. Then, we develop an optical method for efficiently coupling the evanescent field to the regular interference pattern generated by an incoming laser beam and the reflected beam from the substrate underneath the nanowire. This optomechanical coupling is here applied to measure the displacement of 50 nm wide nanowires with sensitivity on the verge of 1 fm/Hz(1/2) at room temperature with a simple laser interferometry set-up. This method opens the door to the measurement of the Brownian motion of ultrashort nanowires for the detection of single biomolecular recognition events in liquids, and single molecule spectroscopy in vacuum.

[Microfabricated X-ray Optics Technology Development for the Constellation X-Mission

NASA Technical Reports Server (NTRS)

Schattenburg, Mark L.

2005-01-01

MIT has previously developed advanced methods for the application of silicon microstructures (so-called microcombs) in the precision assembly of foil x-ray optics in support of the Constellation-X Spectroscopy X-ray Telescope (SXT) technology development at the NASA Goddard Space Flight Center (GSFC). During the first year of the above Cooperative Agreement, MIT has developed a new, mature, potentially high- yield process for the manufacturing of microcombs that can be applied to a range of substrates independent of thickness. MIT also developed techniques to extract microcomb accuracy from an assembly truss metrology test stand and to extend the dynamic range of its Shack-Hartmann foil metrology tool. The placement repeatability of foil optics with microcombs in the assembly truss has been improved by a factor of two to approximately 0.15 micron. This was achieved by electric contact determination in favor of determining contact through force measurements. Development work on a stress-free thin foil holder was also supported by this agreement and successfully continued under a different grant.

Recent Advances in Photonic Devices for Optical Computing and the Role of Nonlinear Optics-Part II

NASA Technical Reports Server (NTRS)

Abdeldayem, Hossin; Frazier, Donald O.; Witherow, William K.; Banks, Curtis E.; Paley, Mark S.

2007-01-01

The twentieth century has been the era of semiconductor materials and electronic technology while this millennium is expected to be the age of photonic materials and all-optical technology. Optical technology has led to countless optical devices that have become indispensable in our daily lives in storage area networks, parallel processing, optical switches, all-optical data networks, holographic storage devices, and biometric devices at airports. This chapters intends to bring some awareness to the state-of-the-art of optical technologies, which have potential for optical computing and demonstrate the role of nonlinear optics in many of these components. Our intent, in this Chapter, is to present an overview of the current status of optical computing, and a brief evaluation of the recent advances and performance of the following key components necessary to build an optical computing system: all-optical logic gates, adders, optical processors, optical storage, holographic storage, optical interconnects, spatial light modulators and optical materials.

Precision Optical Coatings for Large Space Telescope Mirrors

NASA Astrophysics Data System (ADS)

Sheikh, David

This proposal “Precision Optical Coatings for Large Space Telescope Mirrors” addresses the need to develop and advance the state-of-the-art in optical coating technology. NASA is considering large monolithic mirrors 1 to 8-meters in diameter for future telescopes such as HabEx and LUVOIR. Improved large area coating processes are needed to meet the future requirements of large astronomical mirrors. In this project, we will demonstrate a broadband reflective coating process for achieving high reflectivity from 90-nm to 2500-nm over a 2.3-meter diameter coating area. The coating process is scalable to larger mirrors, 6+ meters in diameter. We will use a battery-driven coating process to make an aluminum reflector, and a motion-controlled coating technology for depositing protective layers. We will advance the state-of-the-art for coating technology and manufacturing infrastructure, to meet the reflectance and wavefront requirements of both HabEx and LUVOIR. Specifically, we will combine the broadband reflective coating designs and processes developed at GSFC and JPL with large area manufacturing technologies developed at ZeCoat Corporation. Our primary objectives are to: Demonstrate an aluminum coating process to create uniform coatings over large areas with near-theoretical aluminum reflectance Demonstrate a motion-controlled coating process to apply very precise 2-nm to 5- nm thick protective/interference layers to large areas, Demonstrate a broadband coating system (90-nm to 2500-nm) over a 2.3-meter coating area and test it against the current coating specifications for LUVOIR/HabEx. We will perform simulated space-environment testing, and we expect to advance the TRL from 3 to >5 in 3-years.

Center for Applied Optics Studies: an investment in Indiana's future

NASA Astrophysics Data System (ADS)

Schuh, Delbert J., II; Khorana, Brij M.

1992-05-01

To understand the involvement of the State of Indiana with the Center for Applied Optics at Rose-Hulman Institute of Technology, it is best to start with an explanation of the Indiana Corporation for Science and Technology (CST), its basic charter and its programs. Established in 1982 as a private not-for-profit corporation, CST was formed to promote economic development within the State of Indiana. Two programs that were initially a part of CST's charter and supported with state dollars were a seed capital investment program, aimed at developing new products and processes, and the establishment of university centers of technology development. The former was conceived to create jobs and new, technologically advanced industries in Indiana. The latter was an attempt to encourage technology transfer from the research laboratories of the state universities to the production lines of Indiana industry. Recently, CST has undergone a name change to the Indiana Business Modernization and Technology Corporation (BMT) and adopted an added responsibility of proactive assistance to small- and medium-sized businesses in order to enhance the state's industrial competitiveness.

Preparation, Properties, and Development of Calcium Lanthanum Sulfide as an 8- to 12-micrometer Transmitting Ceramic

DTIC Science & Technology

1989-09-01

Advanced Optical Ceramics Phase "O," by S. Musikant , R. A. Tanzilli, R. J. Charles, G. A. Slack, W. White, and R. M. Cannon. Philadelphia, Penna...1977-February 15, 1978, GE Document No. 78SDR2195.) 2. -----.- Advanced Optical Ceramics, Phase II, by S. Musikant , R. M. Cannon, Jr., C. E. Dulka, J...Document DIN:80SDR2172.) 3. - .....- Advanced Optical Ceramics, Phase I, by S. Musikant , R. M. Cannon, Jr., C. E. Dulka, A. Gatti, J. J. Gebhardt, W. A

Far Ultraviolet Refractive Index of Optical Materials for Solar Blind Channel (SBC) Filters for HST Advanced Camera for Surveys

NASA Technical Reports Server (NTRS)

Leviton, Douglas B.; Madison, Timothy J.; Petrone, Peter

1998-01-01

Refractive index measurements using the minimum deviation method have been carried out for prisms of a variety of far ultraviolet optical materials used in the manufacture of Solar Blind Channel (SBC) filters for the HST Advanced Camera for Surveys (ACS). Some of the materials measured are gaining popularity in a variety of high technology applications including high power excimer lasers and advanced microlithography optics operating in a wavelength region where high quality knowledge of optical material properties is sparse. Our measurements are of unusually high accuracy and precision for this wavelength region owing to advanced instrumentation in the large vacuum chamber of the Diffraction Grating Evaluation Facility (DGEF) at Goddard Space Flight Center (GSFC). Index values for CaF2, BaF2, LiF, and far ultraviolet grades of synthetic sapphire and synthetic fused silica are reported and compared with values from the literature.

A landmark recognition and tracking experiment for flight on the Shuttle/Advanced Technology Laboratory (ATL)

NASA Technical Reports Server (NTRS)

Welch, J. D.

1975-01-01

The preliminary design of an experiment for landmark recognition and tracking from the Shuttle/Advanced Technology Laboratory is described. It makes use of parallel coherent optical processing to perform correlation tests between landmarks observed passively with a telescope and previously made holographic matched filters. The experimental equipment including the optics, the low power laser, the random access file of matched filters and the electro-optical readout device are described. A real time optically excited liquid crystal device is recommended for performing the input non-coherent optical to coherent optical interface function. A development program leading to a flight experiment in 1981 is outlined.

Multimodality Imaging of Myocardial Injury and Remodeling

PubMed Central

Kramer, Christopher M.; Sinusas, Albert J.; Sosnovik, David E.; French, Brent A.; Bengel, Frank M.

2011-01-01

Advances in cardiovascular molecular imaging have come at a rapid pace over the last several years. Multiple approaches have been taken to better understand the structural, molecular, and cellular events that underlie the progression from myocardial injury to myocardial infarction (MI) and, ultimately, to congestive heart failure. Multimodality molecular imaging including SPECT, PET, cardiac MRI, and optical approaches is offering new insights into the pathophysiology of MI and left ventricular remodeling in small-animal models. Targets that are being probed include, among others, angiotensin receptors, matrix metalloproteinases, integrins, apoptosis, macrophages, and sympathetic innervation. It is only a matter of time before these advances are applied in the clinical setting to improve post-MI prognostication and identify appropriate therapies in patients to prevent the onset of congestive heart failure. PMID:20395347

Miniaturization as a key factor to the development and application of advanced metrology systems

NASA Astrophysics Data System (ADS)

Furlong, Cosme; Dobrev, Ivo; Harrington, Ellery; Hefti, Peter; Khaleghi, Morteza

2012-10-01

Recent technological advances of miniaturization engineering are enabling the realization of components and systems with unprecedented capabilities. Such capabilities, which are significantly beneficial to scientific and engineering applications, are impacting the development and the application of optical metrology systems for investigations under complex boundary, loading, and operating conditions. In this paper, and overview of metrology systems that we are developing is presented. Systems are being developed and applied to high-speed and high-resolution measurements of shape and deformations under actual operating conditions for such applications as sustainability, health, medical diagnosis, security, and urban infrastructure. Systems take advantage of recent developments in light sources and modulators, detectors, microelectromechanical (MEMS) sensors and actuators, kinematic positioners, rapid prototyping fabrication technologies, as well as software engineering.

State-of-the-art of optics in China reviewed

NASA Astrophysics Data System (ADS)

Wang, Daheng; Wo, Xinneng

1985-06-01

The state-of-the-art of optics and applied optics in China is reviewed. Developments in lasers, infrared and opto-electronic techniques, optical metrology, high-speed photography, holography and information processing, nonlinear optics, optical fiber communications and optical techniques are described. Further development of optics and applied optics in China are proposed.

Advanced optical components for next-generation photonic networks

NASA Astrophysics Data System (ADS)

Yoo, S. J. B.

2003-08-01

Future networks will require very high throughput, carrying dominantly data-centric traffic. The role of Photonic Networks employing all-optical systems will become increasingly important in providing scalable bandwidth, agile reconfigurability, and low-power consumptions in the future. In particular, the self-similar nature of data traffic indicates that packet switching and burst switching will be beneficial in the Next Generation Photonic Networks. While the natural conclusion is to pursue Photonic Packet Switching and Photonic Burst Switching systems, there are significant challenges in realizing such a system due to practical limitations in optical component technologies. Lack of a viable all-optical memory technology will continue to drive us towards exploring rapid reconfigurability in the wavelength domain. We will introduce and discuss the advanced optical component technologies behind the Photonic Packet Routing system designed and demonstrated at UC Davis. The system is capable of packet switching and burst switching, as well as circuit switching with 600 psec switching speed and scalability to 42 petabit/sec aggregated switching capacity. By utilizing a combination of rapidly tunable wavelength conversion and a uniform-loss cyclic frequency (ULCF) arrayed waveguide grating router (AWGR), the system is capable of rapidly switching the packets in wavelength, time, and space domains. The label swapping module inside the Photonic Packet Routing system containing a Mach-Zehnder wavelength converter and a narrow-band fiber Bragg-grating achieves all-optical label swapping with optical 2R (potentially 3R) regeneration while maintaining optical transparency for the data payload. By utilizing the advanced optical component technologies, the Photonic Packet Routing system successfully demonstrated error-free, cascaded, multi-hop photonic packet switching and routing with optical-label swapping. This paper will review the advanced optical component technologies and their role in the Next Generation Photonic Networks.

Zeolite Crystal Growth in Microgravity and on Earth

NASA Technical Reports Server (NTRS)

2003-01-01

The Center for Advanced Microgravity Materials Processing (CAMMP), a NASA-sponsored Research Partnership Center, is working to improve zeolite materials for storing hydrogen fuel. CAMMP is also applying zeolites to detergents, optical cables, gas and vapor detection for environmental monitoring and control, and chemical production techniques that significantly reduce by-products that are hazardous to the environment. Shown here are zeolite crystals (top) grown in a ground control experiment and grown in microgravity on the USML-2 mission (bottom). Zeolite experiments have also been conducted aboard the International Space Station.

SETI: Spreading the net

NASA Astrophysics Data System (ADS)

Carstairs, Ian R.

2002-12-01

Ian R Carstairs reports on efforts to extend the search for extraterrestrial intelligence to X and γ-ray regions. Traditional Search for Extra-Terrestrial Intelligence (SETI) strategies have used radio, microwave and, to a limited extent, optical searches. But this ignores the higher energy X and γ-ray regions that a technologically advanced extraterrestrial civilization might use to attract our attention - using messages encoded in discrete photon-counting exchange, much like the signals seen from pulsars. Here, the methods used in high-energy pulsar detection and analysis are reviewed and applied to this new SETI initiative.

Optical fiber sensors embedded in flexible polymer foils

NASA Astrophysics Data System (ADS)

van Hoe, Bram; van Steenberge, Geert; Bosman, Erwin; Missinne, Jeroen; Geernaert, Thomas; Berghmans, Francis; Webb, David; van Daele, Peter

2010-04-01

In traditional electrical sensing applications, multiplexing and interconnecting the different sensing elements is a major challenge. Recently, many optical alternatives have been investigated including optical fiber sensors of which the sensing elements consist of fiber Bragg gratings. Different sensing points can be integrated in one optical fiber solving the interconnection problem and avoiding any electromagnetical interference (EMI). Many new sensing applications also require flexible or stretchable sensing foils which can be attached to or wrapped around irregularly shaped objects such as robot fingers and car bumpers or which can even be applied in biomedical applications where a sensor is fixed on a human body. The use of these optical sensors however always implies the use of a light-source, detectors and electronic circuitry to be coupled and integrated with these sensors. The coupling of these fibers with these light sources and detectors is a critical packaging problem and as it is well-known the costs for packaging, especially with optoelectronic components and fiber alignment issues are huge. The end goal of this embedded sensor is to create a flexible optical sensor integrated with (opto)electronic modules and control circuitry. To obtain this flexibility, one can embed the optical sensors and the driving optoelectronics in a stretchable polymer host material. In this article different embedding techniques for optical fiber sensors are described and characterized. Initial tests based on standard manufacturing processes such as molding and laser structuring are reported as well as a more advanced embedding technique based on soft lithography processing.

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).

A beamline for high-pressure studies at the Advanced Light Source with a superconducting bending magnet as the source.

PubMed

Kunz, Martin; MacDowell, Alastair A; Caldwell, Wendel A; Cambie, Daniella; Celestre, Richard S; Domning, Edward E; Duarte, Robert M; Gleason, Arianna E; Glossinger, James M; Kelez, Nicholas; Plate, David W; Yu, Tony; Zaug, Joeseph M; Padmore, Howard A; Jeanloz, Raymond; Alivisatos, A Paul; Clark, Simon M

2005-09-01

A new facility for high-pressure diffraction and spectroscopy using diamond anvil high-pressure cells has been built at the Advanced Light Source on beamline 12.2.2. This beamline benefits from the hard X-radiation generated by a 6 T superconducting bending magnet (superbend). Useful X-ray flux is available between 5 keV and 35 keV. The radiation is transferred from the superbend to the experimental enclosure by the brightness-preserving optics of the beamline. These optics are comprised of a plane parabola collimating mirror, followed by a Kohzu monochromator vessel with Si(111) crystals (E/DeltaE approximately equal 7000) and W/B4C multilayers (E/DeltaE approximately equal 100), and then a toroidal focusing mirror with variable focusing distance. The experimental enclosure contains an automated beam-positioning system, a set of slits, ion chambers, the sample positioning goniometry and area detector (CCD or image-plate detector). Future developments aim at the installation of a second endstation dedicated to in situ laser heating and a dedicated high-pressure single-crystal station, applying both monochromatic and polychromatic techniques.

Novel photonics polymer and its application in IT

NASA Astrophysics Data System (ADS)

Koike, Yasuhiro

2003-07-01

In the field of LANs, transmission systems based on a multimode silica fiber network is heading towards capacities of Gb/s. We have proposed a low-loss, high-bandwidth and large-core graded-index plastic optical fiber (GI POF) in data-com. area. We sill show that GI POF enables to virtually eliminate the "modal noise" problem cased by the medium-core silica fibers. Therefore, stable high-speed data transmission is realized by GI POF rather than silica fibers. Furthermore, advent of perfluorinated (PF) polymer based GI POF network can support higher transmission than silica fibers network because of the small material dispersion of PF polymer compared with silica. In addition, we proposed a "highly scattering optical transmission (HSOT) polymer" and applied it to a light guide plate of a liquid crystal display (LCD) backlight. The advanced HSOT polymer backlight that was proposed using the HSOT designing simulation program demonstrated approximately three times higher luminance than the conventional flat-type HSOT backlight of 14.1-inch diagonal because of the microscopic prism structures at the bottom of the advanced HSOT light guide plate. The HSOT polymer containing the optimized heterogeneous structures produced homogeneous scattered light with forward directivity and sufficient color uniformity.

Applied Optics Golden Anniversary commemorative reviews: introduction.

PubMed

Mait, Joseph N; Mendez, Eugenio; Peyghambarian, Nasser; Poon, T-C

2013-01-01

Applied Optics presents three special issues to end its retrospective of Applied Optics' 50 years. The special issues are interference, interferometry, and phase; imaging, optical processing, and telecommunications; and polarization and scattering. The issues, which contain 19 commemorative reviews from some of the journal's luminaries, are summarized.

Optical measurement of arterial mechanical properties: from atherosclerotic plaque initiation to rupture

NASA Astrophysics Data System (ADS)

Nadkarni, Seemantini K.

2013-12-01

During the pathogenesis of coronary atherosclerosis, from lesion initiation to rupture, arterial mechanical properties are altered by a number of cellular, molecular, and hemodynamic processes. There is growing recognition that mechanical factors may actively drive vascular cell signaling and regulate atherosclerosis disease progression. In advanced plaques, the mechanical properties of the atheroma influence stress distributions in the fibrous cap and mediate plaque rupture resulting in acute coronary events. This review paper explores current optical technologies that provide information on the mechanical properties of arterial tissue to advance our understanding of the mechanical factors involved in atherosclerosis development leading to plaque rupture. The optical approaches discussed include optical microrheology and traction force microscopy that probe the mechanical behavior of single cell and extracellular matrix components, and intravascular imaging modalities including laser speckle rheology, optical coherence elastography, and polarization-sensitive optical coherence tomography to measure the mechanical properties of advanced coronary lesions. Given the wealth of information that these techniques can provide, optical imaging modalities are poised to play an increasingly significant role in elucidating the mechanical aspects of coronary atherosclerosis in the future.

The increase in the starting torque of PMSM motor by applying of FOC method

NASA Astrophysics Data System (ADS)

Plachta, Kamil

2017-05-01

The article presents field oriented control method of synchronous permanent magnet motor equipped in optical sensors. This method allows for a wide range regulation of torque and rotational speed of the electric motor. The paper presents mathematical model of electric motor and vector control method. Optical sensors have shorter time response as compared to the inductive sensors, which allow for faster response of the electronic control system to changes of motor loads. The motor driver is based on the digital signal processor which performs advanced mathematical operations in real time. The appliance of Clark and Park transformation in the software defines the angle of rotor position. The presented solution provides smooth adjustment of the rotational speed in the first operating zone and reduces the dead zone of the torque in the second and third operating zones.

APPLIED OPTICS. Voltage-tunable circular photogalvanic effect in silicon nanowires.

PubMed

Dhara, Sajal; Mele, Eugene J; Agarwal, Ritesh

2015-08-14

Electronic bands in crystals can support nontrivial topological textures arising from spin-orbit interactions, but purely orbital mechanisms can realize closely related dynamics without breaking spin degeneracies, opening up applications in materials containing only light elements. One such application is the circular photogalvanic effect (CPGE), which is the generation of photocurrents whose magnitude and polarity depend on the chirality of optical excitation. We show that the CPGE can arise from interband transitions at the metal contacts to silicon nanowires, where inversion symmetry is locally broken by an electric field. Bias voltage that modulates this field further controls the sign and magnitude of the CPGE. The generation of chirality-dependent photocurrents in silicon with a purely orbital-based mechanism will enable new functionalities in silicon that can be integrated with conventional electronics. Copyright © 2015, American Association for the Advancement of Science.

16 nm-resolution lithography using ultra-small-gap bowtie apertures

NASA Astrophysics Data System (ADS)

Chen, Yang; Qin, Jin; Chen, Jianfeng; Zhang, Liang; Ma, Chengfu; Chu, Jiaru; Xu, Xianfan; Wang, Liang

2017-02-01

Photolithography has long been a critical technology for nanoscale manufacturing, especially in the semiconductor industry. However, the diffractive nature of light has limited the continuous advance of optical lithography resolution. To overcome this obstacle, near-field scanning optical lithography (NSOL) is an alternative low-cost technique, whose resolution is determined by the near-field localization that can be achieved. Here, we apply the newly-developed backside milling method to fabricate bowtie apertures with a sub-15 nm gap, which can substantially improve the resolution of NSOL. A highly confined electric near field is produced by localized surface plasmon excitation and nanofocusing of the closely-tapered gap. We show contact lithography results with a record 16 nm resolution (FWHM). This photolithography scheme promises potential applications in data storage, high-speed computation, energy harvesting, and other nanotechnology areas.

Multiple degree of freedom optical pattern recognition

NASA Technical Reports Server (NTRS)

Casasent, D.

1987-01-01

Three general optical approaches to multiple degree of freedom object pattern recognition (where no stable object rest position exists) are advanced. These techniques include: feature extraction, correlation, and artificial intelligence. The details of the various processors are advanced together with initial results.

Using Radar, Lidar, and Radiometer measurements to Classify Cloud Type and Study Middle-Level Cloud Properties

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Zhien

2010-06-29

The project is mainly focused on the characterization of cloud macrophysical and microphysical properties, especially for mixed-phased clouds and middle level ice clouds by combining radar, lidar, and radiometer measurements available from the ACRF sites. First, an advanced mixed-phase cloud retrieval algorithm will be developed to cover all mixed-phase clouds observed at the ACRF NSA site. The algorithm will be applied to the ACRF NSA observations to generate a long-term arctic mixed-phase cloud product for model validations and arctic mixed-phase cloud processes studies. To improve the representation of arctic mixed-phase clouds in GCMs, an advanced understanding of mixed-phase cloud processesmore » is needed. By combining retrieved mixed-phase cloud microphysical properties with in situ data and large-scale meteorological data, the project aim to better understand the generations of ice crystals in supercooled water clouds, the maintenance mechanisms of the arctic mixed-phase clouds, and their connections with large-scale dynamics. The project will try to develop a new retrieval algorithm to study more complex mixed-phase clouds observed at the ACRF SGP site. Compared with optically thin ice clouds, optically thick middle level ice clouds are less studied because of limited available tools. The project will develop a new two wavelength radar technique for optically thick ice cloud study at SGP site by combining the MMCR with the W-band radar measurements. With this new algorithm, the SGP site will have a better capability to study all ice clouds. Another area of the proposal is to generate long-term cloud type classification product for the multiple ACRF sites. The cloud type classification product will not only facilitates the generation of the integrated cloud product by applying different retrieval algorithms to different types of clouds operationally, but will also support other research to better understand cloud properties and to validate model simulations. The ultimate goal is to improve our cloud classification algorithm into a VAP.« less

Perspective and potential of smart optical materials

NASA Astrophysics Data System (ADS)

Choi, Sang H.; Duzik, Adam J.; Kim, Hyun-Jung; Park, Yeonjoon; Kim, Jaehwan; Ko, Hyun-U.; Kim, Hyun-Chan; Yun, Sungryul; Kyung, Ki-Uk

2017-09-01

The increasing requirements of hyperspectral imaging optics, electro/photo-chromic materials, negative refractive index metamaterial optics, and miniaturized optical components from micro-scale to quantum-scale optics have all contributed to new features and advancements in optics technology. Development of multifunctional capable optics has pushed the boundaries of optics into new fields that require new disciplines and materials to maximize the potential benefits. The purpose of this study is to understand and show the fundamental materials and fabrication technology for field-controlled spectrally active optics (referred to as smart optics) that are essential for future industrial, scientific, military, and space applications, such as membrane optics, filters, windows for sensors and probes, telescopes, spectroscopes, cameras, light valves, light switches, and flat-panel displays. The proposed smart optics are based on the Stark and Zeeman effects in materials tailored with quantum dot arrays and thin films made from readily polarizable materials via ferroelectricity or ferromagnetism. Bound excitonic states of organic crystals are also capable of optical adaptability, tunability, and reconfigurability. To show the benefits of smart optics, this paper reviews spectral characteristics of smart optical materials and device technology. Experiments testing the quantum-confined Stark effect, arising from rare earth element doping effects in semiconductors, and applied electric field effects on spectral and refractive index are discussed. Other bulk and dopant materials were also discovered to have the same aspect of shifts in spectrum and refractive index. Other efforts focus on materials for creating field-controlled spectrally smart active optics on a selected spectral range. Surface plasmon polariton transmission of light through apertures is also discussed, along with potential applications. New breakthroughs in micro scale multiple zone plate optics as a micro convex lens are reviewed, along with the newly discovered pseudo-focal point not predicted with conventional optics modeling. Micron-sized solid state beam scanner chips for laser waveguides are reviewed as well.

A modular optical sensor

NASA Astrophysics Data System (ADS)

Conklin, John Albert

This dissertation presents the design of a modular, fiber-optic sensor and the results obtained from testing the modular sensor. The modular fiber-optic sensor is constructed in such manner that the sensor diaphragm can be replaced with different configurations to detect numerous physical phenomena. Additionally, different fiber-optic detection systems can be attached to the sensor. Initially, the modular sensor was developed to be used by university of students to investigate realistic optical sensors and detection systems to prepare for advance studies of micro-optical mechanical systems (MOMS). The design accomplishes this by doing two things. First, the design significantly lowers the costs associated with studying optical sensors by modularizing the sensor design. Second, the sensor broadens the number of physical phenomena that students can apply optical sensing techniques to in a fiber optics sensor course. The dissertation is divided into seven chapters covering the historical development of fiber-optic sensors, a theoretical overview of fiber-optic sensors, the design, fabrication, and the testing of the modular sensor developed in the course of this work. Chapter 1 discusses, in detail, how this dissertation is organized and states the purpose of the dissertation. Chapter 2 presents an historical overview of the development of optical fibers, optical pressure sensors, and fibers, optical pressure sensors, and optical microphones. Chapter 3 reviews the theory of multi-fiber optic detection systems, optical microphones, and pressure sensors. Chapter 4 presents the design details of the modular, optical sensor. Chapter 5 delves into how the modular sensor is fabricated and how the detection systems are constructed. Chapter 6 presents the data collected from the microphone and pressure sensor configurations of the modular sensor. Finally, Chapter 7 discusses the data collected and draws conclusions about the design based on the data collected. Chapter 7 also presents future work needed to expand the functionality and utility of the modular sensor.

US long distance fiber optic networks: Technology, evolution and advanced concepts. Volume 3: Advanced networks and economics

NASA Technical Reports Server (NTRS)

1986-01-01

This study projects until 2000 the evolution of long distance fiber optic networks in the U.S. Volume 1 is the executive Summary. Volume 2 focuses on fiber optic components and systems that are directly related to the operation of long-haul networks. Optimistic, pessimistic and most likely scenarios of technology development are presented. The activities of national and regional companies implementing fiber long haul networks are also highlighted, along with an analysis of the market and regulatory forces affecting network evolution. Volume 3 presents advanced fiber optic network concept definitions. Inter-LATA traffic is quantified and forms the basis for the construction of 11-, 15-, 17-, and 23-node networks. Using the technology projections from Volume 2, a financial model identifies cost drivers and determines circuit mile costs between any two LATAs. A comparison of fiber optics with alternative transmission concludes the report.

US long distance fiber optic networks: Technology, evolution and advanced concepts. Volume 3: Advanced networks and economics

NASA Astrophysics Data System (ADS)

1986-10-01

This study projects until 2000 the evolution of long distance fiber optic networks in the U.S. Volume 1 is the executive Summary. Volume 2 focuses on fiber optic components and systems that are directly related to the operation of long-haul networks. Optimistic, pessimistic and most likely scenarios of technology development are presented. The activities of national and regional companies implementing fiber long haul networks are also highlighted, along with an analysis of the market and regulatory forces affecting network evolution. Volume 3 presents advanced fiber optic network concept definitions. Inter-LATA traffic is quantified and forms the basis for the construction of 11-, 15-, 17-, and 23-node networks. Using the technology projections from Volume 2, a financial model identifies cost drivers and determines circuit mile costs between any two LATAs. A comparison of fiber optics with alternative transmission concludes the report.

Moore's law, lithography, and how optics drive the semiconductor industry

NASA Astrophysics Data System (ADS)

Hutcheson, G. Dan

2018-03-01

When the subject of Moore's Law arises, the important role that lithography plays and how advances in optics have made it all possible is seldom brought up in the world outside of lithography itself. When lithography is mentioned up in the value chain, it's often a critique of how advances are coming too slow and getting far too expensive. Yet advances in lithography are at the core of how Moore's Law is viable. This presentation lays out how technology and the economics of optics in manufacturing interleave to drive the immense value that semiconductors have brought to the world by making it smarter. Continuing these advances will be critical as electronics make the move from smart to cognitive.

Advances in Measuring the Apparent Optical Properties (AOPs) of Optically Complex Waters

NASA Technical Reports Server (NTRS)

Morrow, John H.; Hooker, Stanford B.; Booth, Charles R.; Bernhard, Germar; Lind, Randall N.; Brown, James W.

2010-01-01

This report documents new technology used to measure the apparent optical properties (AOPs) of optically complex waters. The principal objective is to be prepared for the launch of next-generation ocean color satellites with the most capable commercial off-the-shelf (COTS) instrumentation. An enhanced COTS radiometer was the starting point for designing and testing the new sensors. The follow-on steps were to apply the lessons learned towards a new in-water profiler based on a kite-shaped backplane for mounting the light sensors. The next level of sophistication involved evaluating new radiometers emerging from a development activity based on so-called microradiometers. The exploitation of microradiometers resulted in an in-water profiling system, which includes a sensor networking capability to control ancillary sensors like a shadowband or global positioning system (GPS) device. A principal advantage of microradiometers is their flexibility in producing, interconnecting, and maintaining instruments. The full problem set for collecting sea-truth data--whether in coastal waters or the open ocean-- involves other aspects of data collection that were improved for instruments measuring both AOPs and inherent optical properties (IOPs), if the uncertainty budget is to be minimized. New capabilities associated with deploying solar references were developed as well as a compact solution for recovering in-water instrument systems from small boats.

A Fermi-degenerate three-dimentional optical lattice clock

NASA Astrophysics Data System (ADS)

Goban, Akihisa; Campbell, Sara; Hutson, Ross; Marti, G. Edward; Sonderhouse, Lindsay; Robinson, John; Zhang, Wei; Ye, Jun

2017-04-01

The pursuit of better atomic clocks has advanced many research areas, providing better quantum state control, tighter limits on fundamental constant variation, and improved tests of relativity. Recent progress in optical lattice clock to the accuracy of 2E-18 has benefited from the understanding of atomic interactions. Also the precision of clock spectroscopy has been applied to explore many-body interactions including SU(N) symmetry. In our previous 1D optical lattice, atomic interactions cause suppression and broadening of the atomic resonance, limiting the clock stability. To overcome this limitation, we demonstrate a scalable solution that takes advantage of the high density of a degenerate Fermi gas in a three-dimensional optical lattice to protect against on-site interaction shifts. Using an ultrastable laser, we achieve an unprecedented level of atom-light coherence, reaching a spectroscopic quality factor 5.2E15. We investigate clock systematics unique to this design; on-site interactions are resolved so that their contribution to clock shifts is orders of magnitude suppressed compared to the 1D optical lattice experiments. Also, we measure the combined scalar and tensor magic wavelengths for state-independent trapping along all three lattice axes. We acknowledge support from NIST, DARPA and the NSF JILA Physics Frontier Center.

Photosensitive naturally derived resins toward optical 3-D printing

NASA Astrophysics Data System (ADS)

Skliutas, Edvinas; Kasetaite, Sigita; Jonušauskas, Linas; Ostrauskaite, Jolita; Malinauskas, Mangirdas

2018-04-01

Recent advances in material engineering have shown that renewable raw materials, such as plant oils or glycerol, can be applied for synthesis of polymers due to ready availability, inherent biodegradability, limited toxicity, and existence of modifiable functional groups and eventually resulting to a potentially lower cost. After additional chemical modifications (epoxidation, acrylation, double bonds metathesis, etc.), they can be applied in such high-tech areas as stereolithography, which allows fabrication of three-dimensional (3-D) objects. "Autodesk's" 3-D optical printer "Ember" using 405-nm light was implemented for dynamic projection lithography. It enabled straightforward spatio-selective photopolymerization on demand, which allows development of various photosensitive materials. The bio-based resins' photosensitivity was compared to standard "Autodesk" "PR48" and "Formlabs" "Clear" materials. It turned out that the bioresins need a higher energy dose to be cured (a least 16 J · cm - 2 for a single layer varying from 100 to 130 μm). Despite this, submillimeter range 2.5-D structural features were formed, and their morphology was assessed by optical profilometer and scanning electron microscope. It was revealed that a higher exposition dose (up to 26 J · cm - 2) results in a linear increase in the formed structures height, proving controllability of the undergoing process. Overall, the provided results show that naturally derived resins are suitable candidates for tabletop gray-tone lithography.

Research Studies on Advanced Optical Module/Head Designs for Optical Disk Recording Devices

NASA Technical Reports Server (NTRS)

Burke, James J.; Seery, Bernard D.

1993-01-01

The Annual Report of the Optical Data Storage Center of the University of Arizona is presented. Summary reports on continuing projects are presented. Research areas include: magneto-optic media, optical heads, and signal processing.

Current Advances in Lanthanide‐Doped Upconversion Nanostructures for Detection and Bioapplication

PubMed Central

Chen, Cailing

2016-01-01

Along with the development of science and technology, lanthanide‐doped upconversion nanostructures as a new type of materials have taken their place in the field of nanomaterials. Upconversion luminescence is a nonlinear optical phenomenon, which absorbs two or more photons and emits one photon. Compared with traditional luminescence materials, upconversion nanostructures have many advantages, such as weak background interference, long lifetime, low excitation energy, and strong tissue penetration. These interesting nanostructures can be applied in anticounterfeit, solar cell, detection, bioimaging, therapy, and so on. This review is focused on the current advances in lanthanide‐doped upconversion nanostructures, covering not only basic luminescence mechanism, synthesis, and modification methods but also the design and fabrication of upconversion nanostructures, like core–shell nanoparticles or nanocomposites. At last, this review emphasizes the application of upconversion nanostructure in detection and bioimaging and therapy. Learning more about the advances of upconversion nanostructures can help us better exploit their excellent performance and use them in practice. PMID:27840794

Quantum correlation measurements in interferometric gravitational-wave detectors

NASA Astrophysics Data System (ADS)

Martynov, D. V.; Frolov, V. V.; Kandhasamy, S.; Izumi, K.; Miao, H.; Mavalvala, N.; Hall, E. D.; Lanza, R.; Abbott, B. P.; Abbott, R.; Abbott, T. D.; Adams, C.; Adhikari, R. X.; Anderson, S. B.; Ananyeva, A.; Appert, S.; Arai, K.; Aston, S. M.; Ballmer, S. W.; Barker, D.; Barr, B.; Barsotti, L.; Bartlett, J.; Bartos, I.; Batch, J. C.; Bell, A. S.; Betzwieser, J.; Billingsley, G.; Birch, J.; Biscans, S.; Biwer, C.; Blair, C. D.; Bork, R.; Brooks, A. F.; Ciani, G.; Clara, F.; Countryman, S. T.; Cowart, M. J.; Coyne, D. C.; Cumming, A.; Cunningham, L.; Danzmann, K.; Da Silva Costa, C. F.; Daw, E. J.; DeBra, D.; DeRosa, R. T.; DeSalvo, R.; Dooley, K. L.; Doravari, S.; Driggers, J. C.; Dwyer, S. E.; Effler, A.; Etzel, T.; Evans, M.; Evans, T. M.; Factourovich, M.; Fair, H.; Fernández Galiana, A.; Fisher, R. P.; Fritschel, P.; Fulda, P.; Fyffe, M.; Giaime, J. A.; Giardina, K. D.; Goetz, E.; Goetz, R.; Gras, S.; Gray, C.; Grote, H.; Gushwa, K. E.; Gustafson, E. K.; Gustafson, R.; Hammond, G.; Hanks, J.; Hanson, J.; Hardwick, T.; Harry, G. M.; Heintze, M. C.; Heptonstall, A. W.; Hough, J.; Jones, R.; Karki, S.; Kasprzack, M.; Kaufer, S.; Kawabe, K.; Kijbunchoo, N.; King, E. J.; King, P. J.; Kissel, J. S.; Korth, W. Z.; Kuehn, G.; Landry, M.; Lantz, B.; Lockerbie, N. A.; Lormand, M.; Lundgren, A. P.; MacInnis, M.; Macleod, D. M.; Márka, S.; Márka, Z.; Markosyan, A. S.; Maros, E.; Martin, I. W.; Mason, K.; Massinger, T. J.; Matichard, F.; McCarthy, R.; McClelland, D. E.; McCormick, S.; McIntyre, G.; McIver, J.; Mendell, G.; Merilh, E. L.; Meyers, P. M.; Miller, J.; Mittleman, R.; Moreno, G.; Mueller, G.; Mullavey, A.; Munch, J.; Nuttall, L. K.; Oberling, J.; Oppermann, P.; Oram, Richard J.; O'Reilly, B.; Ottaway, D. J.; Overmier, H.; Palamos, J. R.; Paris, H. R.; Parker, W.; Pele, A.; Penn, S.; Phelps, M.; Pierro, V.; Pinto, I.; Principe, M.; Prokhorov, L. G.; Puncken, O.; Quetschke, V.; Quintero, E. A.; Raab, F. J.; Radkins, H.; Raffai, P.; Reid, S.; Reitze, D. H.; Robertson, N. A.; Rollins, J. G.; Roma, V. J.; Romie, J. H.; Rowan, S.; Ryan, K.; Sadecki, T.; Sanchez, E. J.; Sandberg, V.; Savage, R. L.; Schofield, R. M. S.; Sellers, D.; Shaddock, D. A.; Shaffer, T. J.; Shapiro, B.; Shawhan, P.; Shoemaker, D. H.; Sigg, D.; Slagmolen, B. J. J.; Smith, B.; Smith, J. R.; Sorazu, B.; Staley, A.; Strain, K. A.; Tanner, D. B.; Taylor, R.; Thomas, M.; Thomas, P.; Thorne, K. A.; Thrane, E.; Torrie, C. I.; Traylor, G.; Vajente, G.; Valdes, G.; van Veggel, A. A.; Vecchio, A.; Veitch, P. J.; Venkateswara, K.; Vo, T.; Vorvick, C.; Walker, M.; Ward, R. L.; Warner, J.; Weaver, B.; Weiss, R.; Weßels, P.; Willke, B.; Wipf, C. C.; Worden, J.; Wu, G.; Yamamoto, H.; Yancey, C. C.; Yu, Hang; Yu, Haocun; Zhang, L.; Zucker, M. E.; Zweizig, J.; LSC Instrument Authors

2017-04-01

Quantum fluctuations in the phase and amplitude quadratures of light set limitations on the sensitivity of modern optical instruments. The sensitivity of the interferometric gravitational-wave detectors, such as the Advanced Laser Interferometer Gravitational-Wave Observatory (LIGO), is limited by quantum shot noise, quantum radiation pressure noise, and a set of classical noises. We show how the quantum properties of light can be used to distinguish these noises using correlation techniques. Particularly, in the first part of the paper we show estimations of the coating thermal noise and gas phase noise, hidden below the quantum shot noise in the Advanced LIGO sensitivity curve. We also make projections on the observatory sensitivity during the next science runs. In the second part of the paper we discuss the correlation technique that reveals the quantum radiation pressure noise from the background of classical noises and shot noise. We apply this technique to the Advanced LIGO data, collected during the first science run, and experimentally estimate the quantum correlations and quantum radiation pressure noise in the interferometer.

Optical testbed for the LISA phasemeter

NASA Astrophysics Data System (ADS)

Schwarze, T. S.; Fernández Barranco, G.; Penkert, D.; Gerberding, O.; Heinzel, G.; Danzmann, K.

2016-05-01

The planned spaceborne gravitational wave detector LISA will allow the detection of gravitational waves at frequencies between 0.1 mHz and 1 Hz. A breadboard model for the metrology system aka the phasemeter was developed in the scope of an ESA technology development project by a collaboration between the Albert Einstein Institute, the Technical University of Denmark and the Danish industry partner Axcon Aps. It in particular provides the electronic readout of the main interferometer phases besides auxiliary functions. These include clock noise transfer, ADC pilot tone correction, inter-satellite ranging and data transfer. Besides in LISA, the phasemeter can also be applied in future satellite geodesy missions. Here we show the planning and advances in the implementation of an optical testbed for the full metrology chain. It is based on an ultra-stable hexagonal optical bench. This bench allows the generation of three unequal heterodyne beatnotes with a zero phase combination, thus providing the possibility to probe the phase readout for non-linearities in an optical three signal test. Additionally, the utilization of three independent phasemeters will allow the testing of the auxiliary functions. Once working, components can individually be replaced with flight-qualified hardware in this setup.

Polarization-selective optical transmission through a plasmonic metasurface.

PubMed

Pelzman, Charles; Cho, Sang-Yeon

2015-06-22

We present the design, fabrication, and experimental characterization of a nanoslit-based metasurface that offers polarization-selective optical transmission for advanced imaging applications. The metasurface consists of an array of meta-atoms, constructed with two orthogonally coupled subwavelength apertures. Highly enhanced optical transmission was achieved by selective excitation of surface plasmon waves on the metasurface. By rotating the orientation of the linearly polarized incident beam, switching of enhanced optical transmission bands through the metasurface was experimentally demonstrated. This demonstration is a significant step towards developing advanced multispectral imaging devices.

Polarization-selective optical transmission through a plasmonic metasurface

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pelzman, Charles; Cho, Sang-Yeon, E-mail: sangycho@nmsu.edu

2015-06-22

We present the design, fabrication, and experimental characterization of a nanoslit-based metasurface that offers polarization-selective optical transmission for advanced imaging applications. The metasurface consists of an array of meta-atoms, constructed with two orthogonally coupled subwavelength apertures. Highly enhanced optical transmission was achieved by selective excitation of surface plasmon waves on the metasurface. By rotating the orientation of the linearly polarized incident beam, switching of enhanced optical transmission bands through the metasurface was experimentally demonstrated. This demonstration is a significant step towards developing advanced multispectral imaging devices.

Recent advances in vacuum sciences and applications

NASA Astrophysics Data System (ADS)

Mozetič, M.; Ostrikov, K.; Ruzic, D. N.; Curreli, D.; Cvelbar, U.; Vesel, A.; Primc, G.; Leisch, M.; Jousten, K.; Malyshev, O. B.; Hendricks, J. H.; Kövér, L.; Tagliaferro, A.; Conde, O.; Silvestre, A. J.; Giapintzakis, J.; Buljan, M.; Radić, N.; Dražić, G.; Bernstorff, S.; Biederman, H.; Kylián, O.; Hanuš, J.; Miloševič, S.; Galtayries, A.; Dietrich, P.; Unger, W.; Lehocky, M.; Sedlarik, V.; Stana-Kleinschek, K.; Drmota-Petrič, A.; Pireaux, J. J.; Rogers, J. W.; Anderle, M.

2014-04-01

Recent advances in vacuum sciences and applications are reviewed. Novel optical interferometer cavity devices enable pressure measurements with ppm accuracy. The innovative dynamic vacuum standard allows for pressure measurements with temporal resolution of 2 ms. Vacuum issues in the construction of huge ultra-high vacuum devices worldwide are reviewed. Recent advances in surface science and thin films include new phenomena observed in electron transport near solid surfaces as well as novel results on the properties of carbon nanomaterials. Precise techniques for surface and thin-film characterization have been applied in the conservation technology of cultural heritage objects and recent advances in the characterization of biointerfaces are presented. The combination of various vacuum and atmospheric-pressure techniques enables an insight into the complex phenomena of protein and other biomolecule conformations on solid surfaces. Studying these phenomena at solid-liquid interfaces is regarded as the main issue in the development of alternative techniques for drug delivery, tissue engineering and thus the development of innovative techniques for curing cancer and cardiovascular diseases. A review on recent advances in plasma medicine is presented as well as novel hypotheses on cell apoptosis upon treatment with gaseous plasma. Finally, recent advances in plasma nanoscience are illustrated with several examples and a roadmap for future activities is presented.

Integrated design course of applied optics focusing on operating and maintaining abilities

NASA Astrophysics Data System (ADS)

Xu, Zhongjie; Ning, Yu; Jiang, Tian; Cheng, Xiangai

2017-08-01

The abilities of operating and maintaining optical instruments are crucial in modern society. Besides the basic knowledge in optics, the optics courses in the National University of Defense Technology also focus on the training on handling typical optical equipment. As the link between classroom courses on applied optics and the field trips, the integrated design course of applied optics aims to give the students a better understanding on several instantly used optical equipment, such as hand-held telescope and periscope, etc. The basic concepts of optical system design are also emphasized as well. The course is arranged rightly after the classroom course of applied optics and composed of experimental and design tasks. The experimental tasks include the measurements of aberrations and major parameters of a primitive telescope, while in the design parts, the students are asked to design a Keplerian telescope. The whole course gives a deepened understandings on the concepts, assembling, and operating of telescopes. The students are also encouraged to extend their interests on other typical optical instruments.

Education programs of the Institute for Optical Sciences at the University of Toronto

NASA Astrophysics Data System (ADS)

Istrate, Emanuel; Miller, R. J. Dwayne

2009-06-01

The Institute for Optical Sciences at the University of Toronto is an association of faculty members from various departments with research interests in optics. The institute has an extensive program of academic activities, for graduate and undergraduate students, as well as public outreach. For undergraduate students, we have a course on holography. We provide opportunities for students to gain optics experience through research by providing access to summer research positions and by enrolling them in the Research Skills Program, a summer course teaching the basic skills needed in research. For graduate students, we offer the Distinguished Visiting Scientists program, where world-renowned researchers come for a week, giving a series of 3 lectures and interacting closely with students and professors. The extended stay allows the program to run like a mini-course. We launched a Collaborative Master's Program in Optics, where students earn a degree from their home department, along with a certification of participation in the collaborative program. Physics, Chemistry and Engineering students attending together are exposed to the various points of view on optics, ranging from the pure to the applied sciences. For the general public, we offer the Stoicheff Lecture, a yearly public lecture on optics, organized with the Royal Canadian Institute. Our institute also initiated Science Rendezvous, a yearly public celebration of science across the Greater Toronto Area, with lab tours, demonstrations, and other opportunities to learn about science and those who are actively advancing it. This year, this event attracted over 20,000 attendees.

A method of rapidly evaluating image quality of NED optical system

NASA Astrophysics Data System (ADS)

Sun, Qi; Qiu, Chuankai; Yang, Huan

2014-11-01

In recent years, with the development of technology of micro-display, advanced optics and the software and hardware, near-to-eye display ( NED) optical system will have a wide range of potential applications in the fields of amusement and virtual reality. However, research on the evaluating image quality of this kind optical system is comparatively lagging behind. Although now there are some methods and equipment for evaluation, they can't be applied in commercial production because of their complex operation and inaccuracy. In this paper, an academic method is proposed and a Rapid Evaluation System (RES) is designed to evaluate the image of optical system rapidly and exactly. Firstly, a set of parameters that eyes are sensitive to and also express the quality of system should be extracted and quantized to be criterion, so the evaluation standards can be established. Then, some parameters can be detected by RES consisted of micro-display, CCD camera and computer and so on. By process of scaling, the measuring results of the RES are exact and creditable, relationship between object measurement, subjective evaluation and the RES will be established. After that, image quality of optical system can be evaluated just by detecting parameters of that. The RES is simple and the results of evaluation are exact and keeping with human vision. So the method can be used not only for optimizing design of optical system, but also for evaluation in commercial production.

Far-ultraviolet refractive index of optical materials for solar blind channel (SBC) filters for the HST advanced camera for surveys (ACS)

NASA Astrophysics Data System (ADS)

Leviton, Douglas B.; Madison, Timothy J.; Petrone, Peter

1998-10-01

Refractive index measurements using the minimum deviation method have been carried out for prisms of a variety of far ultraviolet optical materials used in the manufacture of Solar Blind Channel (SBC) filters for the HST Advanced Camera for Surveys (ACS). Some of the materials measured are gaining popularity in a variety of high technology applications including high power excimer lasers and advanced microlithography optics operating in a wavelength region where high quality knowledge of optical material properties is sparse yet critical. Our measurements are of unusually high accuracy and precision for this wavelength region owing to advanced instrumentation in the large vacuum chamber of the Diffraction Grating Evaluation Facility (DGEF) at Goddard Space Flight Center (GSFC) used to implement a minimum deviation method refractometer. Index values for CaF2, BaF2, LiF, and far ultraviolet grades of synthetic sapphire and synthetic fused silica are reported and compared with values from the literature.

Optical high-performance computing: introduction to the JOSA A and Applied Optics feature.

PubMed

Caulfield, H John; Dolev, Shlomi; Green, William M J

2009-08-01

The feature issues in both Applied Optics and the Journal of the Optical Society of America A focus on topics of immediate relevance to the community working in the area of optical high-performance computing.

Advancement of Miniature Optic Gas Sensor (MOGS) Probe Technology

NASA Technical Reports Server (NTRS)

Chullen, Cinda

2015-01-01

Advancement of Miniature Optic Gas Sensor (MOGS) Probe Technology" project will investigate newly developed optic gas sensors delivered from a Small Business Innovative Research (SBIR) Phase II effort. A ventilation test rig will be designed and fabricated to test the sensors while integrated with a Suited Manikin Test Apparatus (SMTA). Once the sensors are integrated, a series of test points will be completed to verify that the sensors can withstand Advanced Suit Portable Life Support System (PLSS) environments and associated human metabolic profiles for changes in pressure and levels of Oxygen (ppO2), carbon dioxide (ppCO2), and humidity (ppH2O).

Advances toward submicron resolution optics for x-ray instrumentation and applications

NASA Astrophysics Data System (ADS)

Cordier, Mark; Stripe, Benjamin; Yun, Wenbing; Lau, S. H.; Lyon, Alan; Reynolds, David; Lewis, Sylvia J. Y.; Chen, Sharon; Semenov, Vladimir A.; Spink, Richard I.; Seshadri, Srivatsan

2017-08-01

Sigray's axially symmetric x-ray optics enable advanced microanalytical capabilities for focusing x-rays to microns-scale to submicron spot sizes, which can potentially unlock many avenues for laboratory micro-analysis. The design of these optics allows submicron spot sizes even at low x-ray energies, enabling research into low atomic number elements and allows increased sensitivity of grazing incidence measurements and surface analysis. We will discuss advances made in the fabrication of these double paraboloidal mirror lenses designed for use in laboratory x-ray applications. We will additionally present results from as-built paraboloids, including surface figure error and focal spot size achieved to-date.

Advanced NDE research in electromagnetic, thermal, and coherent optics

NASA Technical Reports Server (NTRS)

Skinner, S. Ballou

1992-01-01

A new inspection technology called magneto-optic/eddy current imaging was investigated. The magneto-optic imager makes readily visible irregularities and inconsistencies in airframe components. Other research observed in electromagnetics included (1) disbond detection via resonant modal analysis; (2) AC magnetic field frequency dependence of magnetoacoustic emission; and (3) multi-view magneto-optic imaging. Research observed in the thermal group included (1) thermographic detection and characterization of corrosion in aircraft aluminum; (2) a multipurpose infrared imaging system for thermoelastic stress detection; (3) thermal diffusivity imaging of stress induced damage in composites; and (4) detection and measurement of ice formation on the space shuttle main fuel tank. Research observed in the optics group included advancements in optical nondestructive evaluation (NDE).

Diffraction-limited imaging with very large telescopes; Proceedings of the NATO Advanced Study Institute, Cargese, France, Sept. 13-23, 1988

NASA Astrophysics Data System (ADS)

Alloin, D. M.; Mariotti, J.-M.

Recent advances in optics and observation techniques for very large astronomical telescopes are discussed in reviews and reports. Topics addressed include Fourier optics and coherence, optical propagation and image formation through a turbulent atmosphere, radio telescopes, continuously deformable telescopes for optical interferometry (I), amplitude estimation from speckle I, noise calibration of speckle imagery, and amplitude estimation from diluted-array I. Consideration is given to first-order imaging methods, speckle imaging with the PAPA detector and the Knox-Thompson algorithm, phase-closure imaging, real-time wavefront sensing and adaptive optics, differential I, astrophysical programs for high-angular-resolution optical I, cophasing telescope arrays, aperture synthesis for space observatories, and lunar occultations for marcsec resolution.

Driving Innovation in Optical Networking

NASA Astrophysics Data System (ADS)

Colizzi, Ernesto

Over the past 30 years, network applications have changed with the advent of innovative services spanning from high-speed broadband access to mobile data communications and to video signal distribution. To support this service evolution, optical transport infrastructures have changed their role. Innovations in optical networking have not only allowed the pure "bandwidth per fiber" increase, but also the realization of highly dependable and easy-to-manage networks. This article analyzes the innovations that have characterized the optical networking solutions from different perspectives, with a specific focus on the advancements introduced by Alcatel-Lucent's research and development laboratories located in Italy. The advancements of optical networking will be explored and discussed through Alcatel-Lucent's optical products to contextualize each innovation with the market evolution.

Microscanners for optical endomicroscopic applications

NASA Astrophysics Data System (ADS)

Hwang, Kyungmin; Seo, Yeong-Hyeon; Jeong, Ki-Hun

2017-12-01

MEMS laser scanning enables the miniaturization of endoscopic catheters for advanced endomicroscopy such as confocal microscopy, multiphoton microscopy, optical coherence tomography, and many other laser scanning microscopy. These advanced biomedical imaging modalities open a great potential for in vivo optical biopsy without surgical excision. They have huge capabilities for detecting on-demand early stage cancer with non-invasiveness. In this article, the scanning arrangement, trajectory, and actuation mechanism of endoscopic microscanners and their endomicroscopic applications will be overviewed.

Application of optical spectroscopic techniques for disease diagnosis

NASA Astrophysics Data System (ADS)

Saha, Anushree

Optical spectroscopy, a truly non-invasive tool for remote diagnostics, is capable of providing valuable information on the structure and function of molecules. However, most spectroscopic techniques suffer from drawbacks, which limit their application. As a part of my dissertation work, I have developed theoretical and experimental methods to address the above mentioned issues. I have successfully applied these methods for monitoring the physical, chemical and biochemical parameters of biomolecules involved in some specific life threatening diseases like lead poisoning and age-related macular degeneration (AMD). I presented optical studies of melanosomes, which are one of the vital organelles in the human eye, also known to be responsible for a disease called age-related macular degeneration (AMD), a condition of advanced degeneration which causes progressive blindness. I used Raman spectroscopy, to first chemically identify the composition of melanosome, and then monitor the changes in its functional and chemical behavior due to long term exposure to visible light. The above study, apart from explaining the role of melanosomes in AMD, also sets the threshold power for lasers used in surgeries and other clinical applications. In the second part of my dissertation, a battery of spectroscopic techniques was successfully applied to explore the different binding sites of lead ions with the most abundant carrier protein molecule in our circulatory system, human serum albumin. I applied optical spectroscopic tools for ultrasensitive detection of heavy metal ions in solution which can also be used for lead detection at a very early stage of lead poisoning. Apart from this, I used Raman microspectroscopy to study the chemical alteration occurring inside a prostate cancer cell as a result of a treatment with a low concentrated aqueous extract of a prospective drug, Nerium Oleander. The experimental methods used in this study has tremendous potential for clinical application and will gain widespread acceptance within next few years from bench to bedside as an inexpensive and non-invasive tool compared to the other technologies.

High throughput optical lithography by scanning a massive array of bowtie aperture antennas at near-field

PubMed Central

Wen, X.; Datta, A.; Traverso, L. M.; Pan, L.; Xu, X.; Moon, E. E.

2015-01-01

Optical lithography, the enabling process for defining features, has been widely used in semiconductor industry and many other nanotechnology applications. Advances of nanotechnology require developments of high-throughput optical lithography capabilities to overcome the optical diffraction limit and meet the ever-decreasing device dimensions. We report our recent experimental advancements to scale up diffraction unlimited optical lithography in a massive scale using the near field nanolithography capabilities of bowtie apertures. A record number of near-field optical elements, an array of 1,024 bowtie antenna apertures, are simultaneously employed to generate a large number of patterns by carefully controlling their working distances over the entire array using an optical gap metrology system. Our experimental results reiterated the ability of using massively-parallel near-field devices to achieve high-throughput optical nanolithography, which can be promising for many important nanotechnology applications such as computation, data storage, communication, and energy. PMID:26525906

Optical system design, analysis, and production for advanced technology systems; Proceedings of the Meeting, Innsbruck, Austria, Apr. 15-17, 1986

NASA Technical Reports Server (NTRS)

Fischer, Robert E. (Editor); Rogers, Philip J. (Editor)

1986-01-01

The present conference considers topics in the fields of optical systems design software, the design and analysis of optical systems, illustrative cases of advanced optical system design, the integration of optical designs into greater systems, and optical fabrication and testing techniques. Attention is given to an extended range diffraction-based merit function for lens design optimization, an assessment of technologies for stray light control and evaluation, the automated characterization of IR systems' spatial resolution, a spectrum of design techniques based on aberration theory, a three-field IR telescope, a large aperture zoom lens for 16-mm motion picture cameras, and the use of concave holographic gratings as monochomators. Also discussed are the use of aspherics in optical systems, glass choice procedures for periscope design, the fabrication and testing of unconventional optics, low mass mirrors for large optics, and the diamond grinding of optical surfaces on aspheric lens molds.

Retinal and anterior eye compartments derive from a common progenitor pool in the avian optic cup

PubMed Central

Venters, Sara J.; Cuenca, Paulina D.

2011-01-01

Purpose The optic cup is created through invagination of the optic vesicle. The morphogenetic rearrangement creates a double-layered cup, with a hinge (the Optic Cup Lip) where the epithelium bends back upon itself. Shortly after the optic cup forms, it is thought to be sub-divided into separate lineages: i) pigmented epithelium in the outer layer; ii) presumptive iris and ciliary body at the most anterior aspect of the inner layer; and iii) presumptive neural retina in the remainder of the inner layer. We test the native developmental potential of the anterior cup to determine if it normally contributes to the retina. Methods Vital dye and green fluorescent protein (GFP) expressing replication-incompetent retroviral vectors were used to label cells in the nascent optic cup and follow their direct progeny throughout development. Label was applied to either the optic cup lip (n=40), or to the domain just posterior to the lip (n=20). Retroviral labeling is a permanent lineage marker and enabled the analysis of advanced stages of development. Results Labeling within the optic cup gave rise to labeled progeny in the posterior optic cup that differentiated as neural retina (20 of 20). In contrast, labeling cells in the optic cup lip gave rise to progeny of labeled cells arrayed in a linear progression, from the lip into the neural retina (36 of 40). Label was retained in cells at the optic cup lip, regardless of age at examination. In older embryos, labeled progeny delaminated from the optic cup lip to differentiate as muscle of the pupillary margin. Conclusions The data show that the cells at the optic cup lip are a common progenitor population for pigmented epithelium, anterior eye tissues (ciliary body, iris, and pupillary muscle) and retinal neurons. The findings are supportive of an interpretation where the optic cup lip is a specialized niche containing a multipotent progenitor population. PMID:22219630

Coordinating standards and applications for optical water quality sensor networks

USGS Publications Warehouse

Bergamaschi, B.; Pellerin, B.

2011-01-01

Joint USGS-CUAHSI Workshop: In Situ Optical Water Quality Sensor Networks; Shepherdstown, West Virginia, 8-10 June 2011; Advanced in situ optical water quality sensors and new techniques for data analysis hold enormous promise for advancing scientific understanding of aquatic systems through measurements of important biogeochemical parameters at the time scales over which they vary. High-frequency and real-time water quality data also provide the opportunity for early warning of water quality deterioration, trend detection, and science-based decision support. However, developing networks of optical sensors in freshwater systems that report reliable and comparable data across and between sites remains a challenge to the research and monitoring community. To address this, the U.S. Geological Survey (USGS) and the Consortium of Universities for the Advancement of Hydrologic Science, Inc. (CUAHSI), convened a 3-day workshop to explore ways to coordinate development of standards and applications for optical sensors, as well as handling, storage, and analysis of the continuous data they produce.

Multiwavelength metasurfaces through spatial multiplexing

DOE PAGES

Arbabi, Ehsan; Arbabi, Amir; Kamali, Seyedeh Mahsa; ...

2016-09-06

Metasurfaces are two-dimensional arrangements of optical scatterers rationally arranged to control optical wavefronts. Despite the significant advances made in wavefront engineering through metasurfaces, most of these devices are designed for and operate at a single wavelength. Here we show that spatial multiplexing schemes can be applied to increase the number of operation wavelengths. We use a high contrast dielectric transmittarray platform with amorphous silicon nano-posts to demonstrate polarization insensitive metasurface lenses with a numerical aperture of 0.46, that focus light at 915 and 1550 nm to the same focal distance. We investigate two different methods, one based on large scalemore » segmentation and one on meta-atom interleaving, and compare their performances. An important feature of this method is its simple generalization to adding more wavelengths or new functionalities to a device. Furthermore, it provides a relatively straightforward method for achieving multi-functional and multiwavelength metasurface devices.« less

Correlating microscopy techniques and ToF-SIMS analysis of fully grown mammalian oocytes.

PubMed

Gulin, Alexander; Nadtochenko, Victor; Astafiev, Artyom; Pogorelova, Valentina; Rtimi, Sami; Pogorelov, Alexander

2016-06-20

The 2D-molecular thin film analysis protocol for fully grown mice oocytes is described using an innovative approach. Time-of-flight secondary ion mass spectrometry (ToF-SIMS), scanning electron microscopy (SEM), atomic force microscopy (AFM) and optical microscopy imaging were applied to the same mice oocyte section on the same sample holder. A freeze-dried mice oocyte was infiltrated into embedding media, e.g. Epon, and then was cut with a microtome and 2 μm thick sections were transferred onto an ITO coated conductive glass. Mammalian oocytes can contain "nucleolus-like body" (NLB) units and ToF-SIMS analysis was used to investigate the NLB composition. The ion-spatial distribution in the cell components was identified and compared with the images acquired by SEM, AFM and optical microscopy. This study presents a significant advancement in cell embryology, cell physiology and cancer-cell biochemistry.

Applying tattoo dye as a third-harmonic generation contrast agent for in vivo optical virtual biopsy of human skin

NASA Astrophysics Data System (ADS)

Tsai, Ming-Rung; Lin, Chen-Yu; Liao, Yi-Hua; Sun, Chi-Kuang

2013-02-01

Third-harmonic generation (THG) microscopy has been reported to provide intrinsic contrast in elastic fibers, cytoplasmic membrane, nucleus, actin filaments, lipid bodies, hemoglobin, and melanin in human skin. For advanced molecular imaging, exogenous contrast agents are developed for a higher structural or molecular specificity. We demonstrate the potential of the commonly adopted tattoo dye as a THG contrast agent for in vivo optical biopsy of human skin. Spectroscopy and microscopy experiments were performed on cultured cells with tattoo dyes, in tattooed mouse skin, and in tattooed human skin to demonstrate the THG enhancement effect. Compared with other absorbing dyes or nanoparticles used as exogenous THG contrast agents, tattoo dyes are widely adopted in human skin so that future clinical biocompatibility evaluation is relatively achievable. Combined with the demonstrated THG enhancement effect, tattoo dyes show their promise for future clinical imaging applications.

High Storage Efficiency and Large Fractional Delay of EIT-Based Memory

NASA Astrophysics Data System (ADS)

Chen, Yi-Hsin; Lee, Meng-Jung; Wang, I.-Chung; Du, Shengwang; Chen, Yong-Fan; Chen, Ying-Cheng; Yu, Ite

2013-05-01

In long-distance quantum communication and optical quantum computation, an efficient and long-lived quantum memory is an important component. We first experimentally demonstrated that a time-space-reversing method plus the optimum pulse shape can improve the storage efficiency (SE) of light pulses to 78% in cold media based on the effect of electromagnetically induced transparency (EIT). We obtain a large fractional delay of 74 at 50% SE, which is the best record so far. The measured classical fidelity of the recalled pulse is higher than 90% and nearly independent of the storage time, implying that the optical memory maintains excellent phase coherence. Our results suggest the current result may be readily applied to single-photon quantum states due to quantum nature of the EIT light-matter inference. This study advances the EIT-based quantum memory in practical quantum information applications.

Fabrication and testing of 4.2m off-axis aspheric primary mirror of Daniel K. Inouye Solar Telescope

NASA Astrophysics Data System (ADS)

Oh, Chang Jin; Lowman, Andrew E.; Smith, Greg A.; Su, Peng; Huang, Run; Su, Tianquan; Kim, Daewook; Zhao, Chunyu; Zhou, Ping; Burge, James H.

2016-07-01

Daniel K. Inouye Solar Telescope (formerly known as Advanced Technology Solar Telescope) will be the largest optical solar telescope ever built to provide greatly improved image, spatial and spectral resolution and to collect sufficient light flux of Sun. To meet the requirements of the telescope the design adopted a 4m aperture off-axis parabolic primary mirror with challenging specifications of the surface quality including the surface figure, irregularity and BRDF. The mirror has been completed at the College of Optical Sciences in the University of Arizona and it meets every aspect of requirement with margin. In fact this mirror may be the smoothest large mirror ever made. This paper presents the detail fabrication process and metrology applied to the mirror from the grinding to finish, that include extremely stable hydraulic support, IR and Visible deflectometry, Interferometry and Computer Controlled fabrication process developed at the University of Arizona.

Fiber Optic Surface Plasmon Resonance-Based Biosensor Technique: Fabrication, Advancement, and Application.

PubMed

Liang, Gaoling; Luo, Zewei; Liu, Kunping; Wang, Yimin; Dai, Jianxiong; Duan, Yixiang

2016-05-03

Fiber optic-based biosensors with surface plasmon resonance (SPR) technology are advanced label-free optical biosensing methods. They have brought tremendous progress in the sensing of various chemical and biological species. This review summarizes four sensing configurations (prism, grating, waveguide, and fiber optic) with two ways, attenuated total reflection (ATR) and diffraction, to excite the surface plasmons. Meanwhile, the designs of different probes (U-bent, tapered, and other probes) are also described. Finally, four major types of biosensors, immunosensor, DNA biosensor, enzyme biosensor, and living cell biosensor, are discussed in detail for their sensing principles and applications. Future prospects of fiber optic-based SPR sensor technology are discussed.

Estimation of water quality parameters of inland and coastal waters with the use of a toolkit for processing of remote sensing data

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dekker, A.G.; Hoogenboom, H.J.; Rijkeboer, M.

1997-06-01

Deriving thematic maps of water quality parameters from a remote sensing image requires a number of processing steps, such as calibration, atmospheric correction, air/water interface correction, and application of water quality algorithms. A prototype software environment has recently been developed that enables the user to perform and control these processing steps. Main parts of this environment are: (i) access to the MODTRAN 3 radiative transfer code for removing atmospheric and air-water interface influences, (ii) a tool for analyzing of algorithms for estimating water quality and (iii) a spectral database, containing apparent and inherent optical properties and associated water quality parameters.more » The use of the software is illustrated by applying implemented algorithms for estimating chlorophyll to data from a spectral library of Dutch inland waters with CHL ranging from 1 to 500 pg 1{sup -1}. The algorithms currently implemented in the Toolkit software are recommended for optically simple waters, but for optically complex waters development of more advanced retrieval methods is required.« less

Fiber-optically sensorized composite wing

NASA Astrophysics Data System (ADS)

Costa, Joannes M.; Black, Richard J.; Moslehi, Behzad; Oblea, Levy; Patel, Rona; Sotoudeh, Vahid; Abouzeida, Essam; Quinones, Vladimir; Gowayed, Yasser; Soobramaney, Paul; Flowers, George

2014-04-01

Electromagnetic interference (EMI) immune and light-weight, fiber-optic sensor based Structural Health Monitoring (SHM) will find increasing application in aerospace structures ranging from aircraft wings to jet engine vanes. Intelligent Fiber Optic Systems Corporation (IFOS) has been developing multi-functional fiber Bragg grating (FBG) sensor systems including parallel processing FBG interrogators combined with advanced signal processing for SHM, structural state sensing and load monitoring applications. This paper reports work with Auburn University on embedding and testing FBG sensor arrays in a quarter scale model of a T38 composite wing. The wing was designed and manufactured using fabric reinforced polymer matrix composites. FBG sensors were embedded under the top layer of the composite. Their positions were chosen based on strain maps determined by finite element analysis. Static and dynamic testing confirmed expected response from the FBGs. The demonstrated technology has the potential to be further developed into an autonomous onboard system to perform load monitoring, SHM and Non-Destructive Evaluation (NDE) of composite aerospace structures (wings and rotorcraft blades). This platform technology could also be applied to flight testing of morphing and aero-elastic control surfaces.

New Approaches to Coding Information using Inverse Scattering Transform

NASA Astrophysics Data System (ADS)

Frumin, L. L.; Gelash, A. A.; Turitsyn, S. K.

2017-06-01

Remarkable mathematical properties of the integrable nonlinear Schrödinger equation (NLSE) can offer advanced solutions for the mitigation of nonlinear signal distortions in optical fiber links. Fundamental optical soliton, continuous, and discrete eigenvalues of the nonlinear spectrum have already been considered for the transmission of information in fiber-optic channels. Here, we propose to apply signal modulation to the kernel of the Gelfand-Levitan-Marchenko equations that offers the advantage of a relatively simple decoder design. First, we describe an approach based on exploiting the general N -soliton solution of the NLSE for simultaneous coding of N symbols involving 4 ×N coding parameters. As a specific elegant subclass of the general schemes, we introduce a soliton orthogonal frequency division multiplexing (SOFDM) method. This method is based on the choice of identical imaginary parts of the N -soliton solution eigenvalues, corresponding to equidistant soliton frequencies, making it similar to the conventional OFDM scheme, thus, allowing for the use of the efficient fast Fourier transform algorithm to recover the data. Then, we demonstrate how to use this new approach to control signal parameters in the case of the continuous spectrum.

Developing magnetorheological finishing (MRF) technology for the manufacture of large-aperture optics in megajoule class laser systems

NASA Astrophysics Data System (ADS)

Menapace, Joseph A.

2010-11-01

Over the last eight years we have been developing advanced MRF tools and techniques to manufacture meter-scale optics for use in Megajoule class laser systems. These systems call for optics having unique characteristics that can complicate their fabrication using conventional polishing methods. First, exposure to the high-power nanosecond and sub-nanosecond pulsed laser environment in the infrared (>27 J/cm2 at 1053 nm), visible (>18 J/cm2 at 527 nm), and ultraviolet (>10 J/cm2 at 351 nm) demands ultra-precise control of optical figure and finish to avoid intensity modulation and scatter that can result in damage to the optics chain or system hardware. Second, the optics must be super-polished and virtually free of surface and subsurface flaws that can limit optic lifetime through laser-induced damage initiation and growth at the flaw sites, particularly at 351 nm. Lastly, ultra-precise optics for beam conditioning are required to control laser beam quality. These optics contain customized surface topographical structures that cannot be made using traditional fabrication processes. In this review, we will present the development and implementation of large-aperture MRF tools and techniques specifically designed to meet the demanding optical performance challenges required in large aperture high-power laser systems. In particular, we will discuss the advances made by using MRF technology to expose and remove surface and subsurface flaws in optics during final polishing to yield optics with improve laser damage resistance, the novel application of MRF deterministic polishing to imprint complex topographical information and wavefront correction patterns onto optical surfaces, and our efforts to advance the technology to manufacture largeaperture damage resistant optics.

Developing Magnetorheological Finishing (MRF) Technology for the Manufacture of Large-Aperture Optics in Megajoule Class Laser Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Menapace, J A

2010-10-27

Over the last eight years we have been developing advanced MRF tools and techniques to manufacture meter-scale optics for use in Megajoule class laser systems. These systems call for optics having unique characteristics that can complicate their fabrication using conventional polishing methods. First, exposure to the high-power nanosecond and sub-nanosecond pulsed laser environment in the infrared (>27 J/cm{sup 2} at 1053 nm), visible (>18 J/cm{sup 2} at 527 nm), and ultraviolet (>10 J/cm{sup 2} at 351 nm) demands ultra-precise control of optical figure and finish to avoid intensity modulation and scatter that can result in damage to the optics chainmore » or system hardware. Second, the optics must be super-polished and virtually free of surface and subsurface flaws that can limit optic lifetime through laser-induced damage initiation and growth at the flaw sites, particularly at 351 nm. Lastly, ultra-precise optics for beam conditioning are required to control laser beam quality. These optics contain customized surface topographical structures that cannot be made using traditional fabrication processes. In this review, we will present the development and implementation of large-aperture MRF tools and techniques specifically designed to meet the demanding optical performance challenges required in large-aperture high-power laser systems. In particular, we will discuss the advances made by using MRF technology to expose and remove surface and subsurface flaws in optics during final polishing to yield optics with improve laser damage resistance, the novel application of MRF deterministic polishing to imprint complex topographical information and wavefront correction patterns onto optical surfaces, and our efforts to advance the technology to manufacture large-aperture damage resistant optics.« less

Luminescence Sensors Applied to Water Analysis of Organic Pollutants—An Update

PubMed Central

Ibañez, Gabriela A.; Escandar, Graciela M.

2011-01-01

The development of chemical sensors for environmental analysis based on fluorescence, phosphorescence and chemiluminescence signals continues to be a dynamic topic within the sensor field. This review covers the fundamentals of this type of sensors, and an update on recent works devoted to quantifying organic pollutants in environmental waters, focusing on advances since about 2005. Among the wide variety of these contaminants, special attention has been paid polycyclic aromatic hydrocarbons, pesticides, explosives and emerging organic pollutants. The potential of coupling optical sensors with multivariate calibration methods in order to improve the selectivity is also discussed. PMID:22247654

Optical Measurement and Visualization in High-Pressure, High-Temperature, Aviation Gas Turbine Combustors

NASA Technical Reports Server (NTRS)

Hicks, Yolanda R.; Anderson, Robert C.; Locke, Randy J.

2000-01-01

Planar laser-induced fluorescence (PLIF), planar Mie scattering (PMie), and linear (1-D) spontaneous Raman scattering are applied to flame tube and sector combustors that burn Jet-A fuel at a range of inlet temperatures and pressures that simulate conditions expected in future high-performance civilian gas turbine engines. Chemiluminescence arising from C2 in the flame was also imaged. Flame spectral emissions measurements were obtained using a scanning spectrometer. Several different advanced concept fuel injectors were examined. First-ever PLIF and chemiluminescence data are presented from the 60-atm Gas turbine combustor facility.

An integrated modeling and design tool for advanced optical spacecraft

NASA Technical Reports Server (NTRS)

Briggs, Hugh C.

1992-01-01

Consideration is given to the design and status of the Integrated Modeling of Optical Systems (IMOS) tool and to critical design issues. A multidisciplinary spacecraft design and analysis tool with support for structural dynamics, controls, thermal analysis, and optics, IMOS provides rapid and accurate end-to-end performance analysis, simulations, and optimization of advanced space-based optical systems. The requirements for IMOS-supported numerical arrays, user defined data structures, and a hierarchical data base are outlined, and initial experience with the tool is summarized. A simulation of a flexible telescope illustrates the integrated nature of the tools.

Three new bachelors of photonics in Ontario

NASA Astrophysics Data System (ADS)

Nantel, Marc; Beda, Johann; Grevatt, Treena; Chebbi, Brahim; Jessop, Paul; Song, Shaowen

2004-10-01

After the introduction in 2001 of community college programs at the Photonics Technician/Technologist levels, the need to cover the photonics educational space at the undergraduate level was addressed. In the last year, three very different new undergraduate degrees in photonics have started to develop in Ontario. These programs are presented in this paper. The Honours B.Sc. in Photonics at Wilfrid Laurier University (Waterloo) will develop a strong understanding of the theory and application of photonics, with practical hands-on exposure to optics, fibre optics, and lasers. This program benefits from the particularity that the department offering it combines both Physics and Computer Science. At McMaster University, the Engineering Physics program will provide students with a broad background in basic Engineering, Mathematics, Electronics, and Semiconductors, as well as an opportunity to pursue Photonics in greater depth and to have that fact recognized in the program designation. The Niagara and Algonquin College Bachelor of Applied Technology in Photonics program is co-op and joint between the two institutions. Emphasis is placed on the applied aspects of the field, with the more hands-on experimental learning taking precedence in the first years and the more advanced theoretical subjects following in the latter years.

Recent Advances in Radio and Optical Propagation for Modern Communications, Navigation and Detection Systems

DTIC Science & Technology

1978-04-01

of coherent detection techniques (e.g. laser and optical heterodyning, sensitive to phase fluctuations caused by atmospheric turbulence). The...ATMOSPHERIC OPTICAL EFFECTS 2.1 Atmospheric Refraction The index of refraction n = c/v, with c = velocity of propagation in a vacuum and v ’n air , is... oscillating electrons reradiate and the net effect is to change the phase of the advancing wave. When sufficient molecules are present the moving electrons

Optical Probes for Neurobiological Sensing and Imaging.

PubMed

Kim, Eric H; Chin, Gregory; Rong, Guoxin; Poskanzer, Kira E; Clark, Heather A

2018-05-15

Fluorescent nanosensors and molecular probes are next-generation tools for imaging chemical signaling inside and between cells. Electrophysiology has long been considered the gold standard in elucidating neural dynamics with high temporal resolution and precision, particularly on the single-cell level. However, electrode-based techniques face challenges in illuminating the specific chemicals involved in neural cell activation with adequate spatial information. Measuring chemical dynamics is of fundamental importance to better understand synergistic interactions between neurons as well as interactions between neurons and non-neuronal cells. Over the past decade, significant technological advances in optical probes and imaging methods have enabled entirely new possibilities for studying neural cells and circuits at the chemical level. These optical imaging modalities have shown promise for combining chemical, temporal, and spatial information. This potential makes them ideal candidates to unravel the complex neural interactions at multiple scales in the brain, which could be complemented by traditional electrophysiological methods to obtain a full spatiotemporal picture of neurochemical dynamics. Despite the potential, only a handful of probe candidates have been utilized to provide detailed chemical information in the brain. To date, most live imaging and chemical mapping studies rely on fluorescent molecular indicators to report intracellular calcium (Ca 2+ ) dynamics, which correlates with neuronal activity. Methodological advances for monitoring a full array of chemicals in the brain with improved spatial, temporal, and chemical resolution will thus enable mapping of neurochemical circuits with finer precision. On the basis of numerous studies in this exciting field, we review the current efforts to develop and apply a palette of optical probes and nanosensors for chemical sensing in the brain. There is a strong impetus to further develop technologies capable of probing entire neurobiological units with high spatiotemporal resolution. Thus, we introduce selected applications for ion and neurotransmitter detection to investigate both neurons and non-neuronal brain cells. We focus on families of optical probes because of their ability to sense a wide array of molecules and convey spatial information with minimal damage to tissue. We start with a discussion of currently available molecular probes, highlight recent advances in genetically modified fluorescent probes for ions and small molecules, and end with the latest research in nanosensors for biological imaging. Customizable, nanoscale optical sensors that accurately and dynamically monitor the local environment with high spatiotemporal resolution could lead to not only new insights into the function of all cell types but also a broader understanding of how diverse neural signaling systems act in conjunction with neighboring cells in a spatially relevant manner.

Optimal Performance Monitoring of Hybrid Mid-Infrared Wavelength MIMO Free Space Optical and RF Wireless Networks in Fading Channels

NASA Astrophysics Data System (ADS)

Schmidt, Barnet Michael

An optimal performance monitoring metric for a hybrid free space optical and radio-frequency (RF) wireless network, the Outage Capacity Objective Function, is analytically developed and studied. Current and traditional methods of performance monitoring of both optical and RF wireless networks are centered on measurement of physical layer parameters, the most common being signal-to-noise ratio, error rate, Q factor, and eye diagrams, occasionally combined with link-layer measurements such as data throughput, retransmission rate, and/or lost packet rate. Network management systems frequently attempt to predict or forestall network failures by observing degradations of these parameters and to attempt mitigation (such as offloading traffic, increasing transmitter power, reducing the data rate, or combinations thereof) prior to the failure. These methods are limited by the frequent low sensitivity of the physical layer parameters to the atmospheric optical conditions (measured by optical signal-to-noise ratio) and the radio frequency fading channel conditions (measured by signal-to-interference ratio). As a result of low sensitivity, measurements of this type frequently are unable to predict impending failures sufficiently in advance for the network management system to take corrective action prior to the failure. We derive and apply an optimal measure of hybrid network performance based on the outage capacity of the hybrid optical and RF channel, the outage capacity objective function. The objective function provides high sensitivity and reliable failure prediction, and considers both the effects of atmospheric optical impairments on the performance of the free space optical segment as well as the effect of RF channel impairments on the radio frequency segment. The radio frequency segment analysis considers the three most common RF channel fading statistics: Rayleigh, Ricean, and Nakagami-m. The novel application of information theory to the underlying physics of the gamma-gamma optical channel and radio fading channels in determining the joint hybrid channel outage capacity provides the best performance estimate under any given set of operating conditions. It is shown that, unlike traditional physical layer performance monitoring techniques, the objective function based upon the outage capacity of the hybrid channel at any combination of OSNR and SIR, is able to predict channel degradation and failure well in advance of the actual outage. An outage in the information-theoretic definition occurs when the offered load exceeds the outage capacity under the current conditions of OSNR and SIR. The optical channel is operated at the "long" mid-infrared wavelength of 10000 nm. which provides improved resistance to scattering compared to shorter wavelengths such as 1550 nm.

Genetically Targeted All-Optical Electrophysiology with a Transgenic Cre-Dependent Optopatch Mouse

PubMed Central

Lou, Shan; Adam, Yoav; Weinstein, Eli N.; Williams, Erika; Williams, Katherine; Parot, Vicente; Kavokine, Nikita; Liberles, Stephen; Madisen, Linda; Zeng, Hongkui

2016-01-01

Recent advances in optogenetics have enabled simultaneous optical perturbation and optical readout of membrane potential in diverse cell types. Here, we develop and characterize a Cre-dependent transgenic Optopatch2 mouse line that we call Floxopatch. The animals expressed a blue-shifted channelrhodopsin, CheRiff, and a near infrared Archaerhodopsin-derived voltage indicator, QuasAr2, via targeted knock-in at the rosa26 locus. In Optopatch-expressing animals, we tested for overall health, genetically targeted expression, and function of the optogenetic components. In offspring of Floxopatch mice crossed with a variety of Cre driver lines, we observed spontaneous and optically evoked activity in vitro in acute brain slices and in vivo in somatosensory ganglia. Cell-type-specific expression allowed classification and characterization of neuronal subtypes based on their firing patterns. The Floxopatch mouse line is a useful tool for fast and sensitive characterization of neural activity in genetically specified cell types in intact tissue. SIGNIFICANCE STATEMENT Optical recordings of neural activity offer the promise of rapid and spatially resolved mapping of neural function. Calcium imaging has been widely applied in this mode, but is insensitive to the details of action potential waveforms and subthreshold events. Simultaneous optical perturbation and optical readout of single-cell electrical activity (“Optopatch”) has been demonstrated in cultured neurons and in organotypic brain slices, but not in acute brain slices or in vivo. Here, we describe a transgenic mouse in which expression of Optopatch constructs is controlled by the Cre-recombinase enzyme. This animal enables fast and robust optical measurements of single-cell electrical excitability in acute brain slices and in somatosensory ganglia in vivo, opening the door to rapid optical mapping of neuronal excitability. PMID:27798186

Nonlinear optical microscopy for immunoimaging: a custom optimized system of high-speed, large-area, multicolor imaging

PubMed Central

Li, Hui; Cui, Quan; Zhang, Zhihong; Luo, Qingming

2015-01-01

Background The nonlinear optical microscopy has become the current state-of-the-art for intravital imaging. Due to its advantages of high resolution, superior tissue penetration, lower photodamage and photobleaching, as well as intrinsic z-sectioning ability, this technology has been widely applied in immunoimaging for a decade. However, in terms of monitoring immune events in native physiological environment, the conventional nonlinear optical microscope system has to be optimized for live animal imaging. Generally speaking, three crucial capabilities are desired, including high-speed, large-area and multicolor imaging. Among numerous high-speed scanning mechanisms used in nonlinear optical imaging, polygon scanning is not only linearly but also dispersion-freely with high stability and tunable rotation speed, which can overcome disadvantages of multifocal scanning, resonant scanner and acousto-optical deflector (AOD). However, low frame rate, lacking large-area or multicolor imaging ability make current polygonbased nonlinear optical microscopes unable to meet the requirements of immune event monitoring. Methods We built up a polygon-based nonlinear optical microscope system which was custom optimized for immunoimaging with high-speed, large-are and multicolor imaging abilities. Results Firstly, we validated the imaging performance of the system by standard methods. Then, to demonstrate the ability to monitor immune events, migration of immunocytes observed by the system based on typical immunological models such as lymph node, footpad and dorsal skinfold chamber are shown. Finally, we take an outlook for the possible advance of related technologies such as sample stabilization and optical clearing for more stable and deeper intravital immunoimaging. Conclusions This study will be helpful for optimizing nonlinear optical microscope to obtain more comprehensive and accurate information of immune events. PMID:25694951

Optical modulation from an electro-optic polymer based hybrid Fabry-Perot etalon using transparent conducting oxides

NASA Astrophysics Data System (ADS)

Gan, Haiyong; Zhang, Hongxi; DeRose, Christopher T.; Norwood, Robert A.; Fallahi, Mahmoud; Luo, Jingdong; Jen, Alex K.-Y.; Liu, Boyang; Ho, Seng-Tiong; Peyghambarian, Nasser

2007-02-01

Fabry-Perot etalons using electro-optic (EO) organic materials can be used for devices such as tunable filters and spatial light modulators (SLM's) for wavelength division multiplexing (WDM) communication systems 1-5 and ultrafast imaging systems. For these applications the SLM's need to have: (i) low insertion loss, (ii) high speed operation, and (iii) large modulation depth with low drive voltage. Recently, there have been three developments which together can enhance the SLM performance to a higher level. First, low loss distributed Bragg reflector (DBR) mirrors are now used in SLM's to replace thin metal mirrors, resulting in reduced transmission loss, high reflectivity (>99%) and high finesse. Second, EO polymer materials have shown excellent properties for wide bandwidth optical modulation for information technology due to their fabrication flexibility, compatibility with high speed operation, and large EO coefficients at telecommunication wavelengths. For instance, the EO polymer AJL8/APC (AJL8: nonlinear optical chromophore, and APC: amorphous polycarbonate has recently been incorporated into waveguide modulators and achieved good performance for optical modulation. Finally, very low loss transparent conducting oxide (TCO) electrodes have drawn increasing attention for applications in optoelectronic devices. Here we will address how the low loss indium oxide (In IIO 3) electrodes with an absorption coefficient ~1000/cm and conductivity ~204 S/cm can help improve the modulation performance of EO polymer Fabry-Pérot étalons using the advanced electro-optic (EO) polymer material (AJL8/APC). A hybrid etalon structure with one highly conductive indium tin oxide (ITO) electrode outside the etalon cavity and one low-absorption In IIO 3 electrode inside etalon cavity has been demonstrated. High finesse (~234), improved effective applied voltage ratio (~0.25), and low insertion loss (~4 dB) have been obtained. A 10 dB isolation ratio and ~10% modulation depth at 200 kHz with only 5 V applied voltage have been achieved. These results indicate that such etalons are very promising candidates for ultrafast spatial light modulation in information technology.

Highly Non-Linear Optical (NLO) organic crystals and films. Electrooptical organic materials

NASA Technical Reports Server (NTRS)

Mcmanus, Samuel P.; Rosenberger, Franz; Matthews, John

1987-01-01

Devices employing nonlinear optics (NLO) hold great promise for important applications in integrated optics, optical information processing and telecommunications. Properly designed organics possess outstanding optical and electrooptical properties which will substantially advance many technologies including electrooptical switching, optical amplification for communications, and parallel processing for hybrid optical computers. A brief comparison of organic and inorganic materials is given.

Advanced imaging research and development at DARPA

NASA Astrophysics Data System (ADS)

Dhar, Nibir K.; Dat, Ravi

2012-06-01

Advances in imaging technology have huge impact on our daily lives. Innovations in optics, focal plane arrays (FPA), microelectronics and computation have revolutionized camera design. As a result, new approaches to camera design and low cost manufacturing is now possible. These advances are clearly evident in visible wavelength band due to pixel scaling, improvements in silicon material and CMOS technology. CMOS cameras are available in cell phones and many other consumer products. Advances in infrared imaging technology have been slow due to market volume and many technological barriers in detector materials, optics and fundamental limits imposed by the scaling laws of optics. There is of course much room for improvements in both, visible and infrared imaging technology. This paper highlights various technology development projects at DARPA to advance the imaging technology for both, visible and infrared. Challenges and potentials solutions are highlighted in areas related to wide field-of-view camera design, small pitch pixel, broadband and multiband detectors and focal plane arrays.

Optical Verification Laboratory Demonstration System for High Security Identification Cards

NASA Technical Reports Server (NTRS)

Javidi, Bahram

1997-01-01

Document fraud including unauthorized duplication of identification cards and credit cards is a serious problem facing the government, banks, businesses, and consumers. In addition, counterfeit products such as computer chips, and compact discs, are arriving on our shores in great numbers. With the rapid advances in computers, CCD technology, image processing hardware and software, printers, scanners, and copiers, it is becoming increasingly easy to reproduce pictures, logos, symbols, paper currency, or patterns. These problems have stimulated an interest in research, development and publications in security technology. Some ID cards, credit cards and passports currently use holograms as a security measure to thwart copying. The holograms are inspected by the human eye. In theory, the hologram cannot be reproduced by an unauthorized person using commercially-available optical components; in practice, however, technology has advanced to the point where the holographic image can be acquired from a credit card-photographed or captured with by a CCD camera-and a new hologram synthesized using commercially-available optical components or hologram-producing equipment. Therefore, a pattern that can be read by a conventional light source and a CCD camera can be reproduced. An optical security and anti-copying device that provides significant security improvements over existing security technology was demonstrated. The system can be applied for security verification of credit cards, passports, and other IDs so that they cannot easily be reproduced. We have used a new scheme of complex phase/amplitude patterns that cannot be seen and cannot be copied by an intensity-sensitive detector such as a CCD camera. A random phase mask is bonded to a primary identification pattern which could also be phase encoded. The pattern could be a fingerprint, a picture of a face, or a signature. The proposed optical processing device is designed to identify both the random phase mask and the primary pattern [1-3]. We have demonstrated experimentally an optical processor for security verification of objects, products, and persons. This demonstration is very important to encourage industries to consider the proposed system for research and development.

Joint Applied Optics and Chinese Optics Letters feature introduction: digital holography and three-dimensional imaging.

PubMed

Poon, Ting-Chung

2011-12-01

This feature issue serves as a pilot issue promoting the joint issue of Applied Optics and Chinese Optics Letters. It focuses upon topics of current relevance to the community working in the area of digital holography and 3-D imaging. © 2011 Optical Society of America

Recent developments of advanced structures for space optics at Astrium, Germany

NASA Astrophysics Data System (ADS)

Stute, Thomas; Wulz, Georg; Scheulen, Dietmar

2003-12-01

The mechanical division of EADS Astrium GmbH, Friedrichshafen Germany, the former Dornier Satellitensystem GmbH is currently engaged with the development, manufacturing and testing of three different advanced dimensionally stable composite and ceramic material structures for satellite borne optics: -CFRP Camera Structure -Planck Telescope Reflectors -NIRSpec Optical Bench Breadboard for James Web Space Telescope The paper gives an overview over the requirements and the main structural features how these requirements are met. Special production aspects and available test results are reported.

Laser anemometry - Advances and applications 1991; Proceedings of the 4th International Conference, Cleveland, OH, Aug. 5-9, 1991. Vols. 1 & 2

NASA Technical Reports Server (NTRS)

Dybbs, Alexander (Editor); Ghorashi, Bahman (Editor)

1991-01-01

The papers presented in this volume provide an overview of the latest advances in laser anemometry and optical flow diagnostics. Topics discussed include turbulence, jets, and chaos; novel optical techniques for velocity measurements; chemical reactions and combusting flows; and LDA/CFD interface. Attention is also given to particle image velocimetry, high speed flows and aerodynamic flows, internal flows, particle sizing, optics and signal processing, two-phase flows, and general fluid mechanics applications.

Generalized Kramers-Kronig relations in nonlinear optical- and THz-spectroscopy

NASA Astrophysics Data System (ADS)

Peiponen, K.-E.; Saarinen, J. J.

2009-05-01

Kramers-Kronig (K-K) relations have constituted one of the principal tools in the optical spectroscopy for the assessment of the optical properties of media from measured spectra. The underlying principle for the existence of the K-K relations is causality. Thanks to the K-K relations we have achieved a better understanding of both macroscopic and microscopic properties of media. Recently, various kinds of modified K-K relations have been presented in the literature. Such relations have been applied, e.g. to the nonlinear optical properties of polymers. A typical advantage of these generalized K-K relations is that the measured data do not need to be manipulated as in the case of the traditional K-K relations. Hence, the accuracy of the inverted data on linear or nonlinear optical properties of media becomes higher. A novel way to utilize generalized K-K relations is related to the measurement and correction of terahertz spectra in the time-domain reflection spectroscopy. Terahertz spectroscopy is nowadays one of the most rapidly developing fields in modern physics with applications being related to, e.g. security at the airports or inspection of pharmaceutical tablets. While recording THz spectra it is also possible to perform a chemical mapping of species. Therefore, correctness of the spectrum is of crucial importance for the identification of different species. This is possible by the generalized K-K relations. In this review paper we consider advances of K-K relations both in nonlinear optical and THz spectroscopy.

Design and fabrication of sub-wavelength annular apertures on fiber tip for femtosecond laser machining

NASA Astrophysics Data System (ADS)

Tung, Yen-Chun; Chung, Ming-Han; Sung, I.-Hui; Lee, Chih-Kung

2014-03-01

Adopting optical technique to pursue micromachining must make a compromise between the focal spot sizes the depth of focus. The focal spot size determines the minimum features can be fabricated. On the other hand, the depth of focus influences the ease of alignment in positioning the fabrication light beam. A typical approach to bypass the diffraction limit is to adopt the near-field approach, which has spot size in the range of the optical fiber tip. However, the depth of focus of the emitted light beam will be limited to tens of nanometers in most cases, which posts a difficult challenge to control the distance between the optical fiber tip and the sample to be machined optically. More specifically, problems remained in this machining approach, which include issues such as residue induced by laser ablation tends to deposit near the optical fiber tip and leads to loss of coupling efficiency. We proposed a method based on illuminating femtosecond laser through a sub-wavelength annular aperture on metallic film so as to produce Bessel light beam of sub-wavelength while maintaining large depth of focus first. To further advance the ease of use in one such system, producing sub-wavelength annular aperture on a single mode optical fiber head with sub-wavelength focusing ability is detailed. It is shown that this method can be applied in material machining with an emphasis to produce high aspect ratio structure. Simulations and experimental results are presented in this paper.

Recommendations and illustrations for the evaluation of photonic random number generators

NASA Astrophysics Data System (ADS)

Hart, Joseph D.; Terashima, Yuta; Uchida, Atsushi; Baumgartner, Gerald B.; Murphy, Thomas E.; Roy, Rajarshi

2017-09-01

The never-ending quest to improve the security of digital information combined with recent improvements in hardware technology has caused the field of random number generation to undergo a fundamental shift from relying solely on pseudo-random algorithms to employing optical entropy sources. Despite these significant advances on the hardware side, commonly used statistical measures and evaluation practices remain ill-suited to understand or quantify the optical entropy that underlies physical random number generation. We review the state of the art in the evaluation of optical random number generation and recommend a new paradigm: quantifying entropy generation and understanding the physical limits of the optical sources of randomness. In order to do this, we advocate for the separation of the physical entropy source from deterministic post-processing in the evaluation of random number generators and for the explicit consideration of the impact of the measurement and digitization process on the rate of entropy production. We present the Cohen-Procaccia estimate of the entropy rate h (𝜖 ,τ ) as one way to do this. In order to provide an illustration of our recommendations, we apply the Cohen-Procaccia estimate as well as the entropy estimates from the new NIST draft standards for physical random number generators to evaluate and compare three common optical entropy sources: single photon time-of-arrival detection, chaotic lasers, and amplified spontaneous emission.

Sequential x-ray diffraction topography at 1-BM x-ray optics testing beamline at the advanced photon source

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stoupin, Stanislav, E-mail: sstoupin@aps.anl.gov; Shvyd’ko, Yuri; Trakhtenberg, Emil

2016-07-27

We report progress on implementation and commissioning of sequential X-ray diffraction topography at 1-BM Optics Testing Beamline of the Advanced Photon Source to accommodate growing needs of strain characterization in diffractive crystal optics and other semiconductor single crystals. The setup enables evaluation of strain in single crystals in the nearly-nondispersive double-crystal geometry. Si asymmetric collimator crystals of different crystallographic orientations were designed, fabricated and characterized using in-house capabilities. Imaging the exit beam using digital area detectors permits rapid sequential acquisition of X-ray topographs at different angular positions on the rocking curve of a crystal under investigation. Results on sensitivity andmore » spatial resolution are reported based on experiments with high-quality Si and diamond crystals. The new setup complements laboratory-based X-ray topography capabilities of the Optics group at the Advanced Photon Source.« less

Pilot Project for Spaceborne Massive Optical Storage Devices

NASA Technical Reports Server (NTRS)

Chen, Y. J.

1996-01-01

A space bound storage device has many special requirements. In addition to large storage capacity, fas read/ write time, and high reliability, it also needs to have small volume, light weight, low power consumption, radiation hardening, ability to operate in extreme temperature ranges, etc. Holographic optical recording technology, which has been making major advancements in recent years, is an extremely promising candidate. The goal of this pilot project is to demonstrate a laboratory bench-top holographic optical recording storage system (HORSS) based on nonlinear polymer films 1 and/or other advanced photo-refractive materials. This system will be used as a research vehicle to study relevant optical properties of novel holographic optical materials, to explore massive optical storage technologies based on the photo-refractive effect and to evaluate the feasibility of developing a massive storage system, based on holographic optical recording technology, for a space bound experiment in the near future.

Ion beam processing and characterization of advanced optical materials

NASA Astrophysics Data System (ADS)

Zhu, Jie

Ion beams have been extensively applied for materials modification and characterization. In this dissertation, I will focus on the applications of ion beams for advanced optical materials. The first part of my work addresses the effects of 1.0 MeV proton irradiation on photoluminescence (PL) properties of self-assembled InAs QDs. Compared to the QDs grown in a GaAs thin film, the QDs embedded in an AlAs/GaAs superlattice structure exhibits much higher photoluminescence degradation resistance to proton irradiation. Proton irradiation combined with thermal annealing results in significant blueshifts in PL spectra of QDs embedded in GaAs, suggesting enhanced atomic intermixing in the QD systems due to point defects introduced by ion irradiation. In the second part of my work, ion channeling combined with Rutherford backscattering is applied to investigate In-Ga atomic intermixing processes in the proton irradiated InAs QD system. Ion channeling along the growth (<100>) direction shows evidence of In atoms with small displacement from the atomic row, which gives direct signature of QD lattice structures, allowing us to monitor atomic intermixing between In and Ga. Based on the channeling data, a model for In-Ga atomic intermixing in InAs/GaAs QD system is proposed, in which In-Ga atomic intermixing can take place along both the growth direction and the lateral direction in the QD layer. The third part of my dissertation is the elemental mapping of silica-based optical cross section using micron-ion-beam imaging techniques. This work is intended to examine the thermal stability of Ge-doped fiber cores in high-temperature environments. Our measurements show that Ge completely diffuses out of the core region following thermal annealing at 1000°C. This indicates that silica-based optical fibers cannot be used for applications at extreme high temperatures. The final part is the study of the effects of various wet treatment on GaN surface, which is a necessary step during the GaN device fabrication. In our work, the HCL treatment has reduced the Ga concentration on the surface for N type GaN. However, for samples with lower concentration of Si doping or P type GaN samples, this effect does not occur.

Assurance Technology Challenges of Advanced Space Systems

NASA Technical Reports Server (NTRS)

Chern, E. James

2004-01-01

The initiative to explore space and extend a human presence across our solar system to revisit the moon and Mars post enormous technological challenges to the nation's space agency and aerospace industry. Key areas of technology development needs to enable the endeavor include advanced materials, structures and mechanisms; micro/nano sensors and detectors; power generation, storage and management; advanced thermal and cryogenic control; guidance, navigation and control; command and data handling; advanced propulsion; advanced communication; on-board processing; advanced information technology systems; modular and reconfigurable systems; precision formation flying; solar sails; distributed observing systems; space robotics; and etc. Quality assurance concerns such as functional performance, structural integrity, radiation tolerance, health monitoring, diagnosis, maintenance, calibration, and initialization can affect the performance of systems and subsystems. It is thus imperative to employ innovative nondestructive evaluation methodologies to ensure quality and integrity of advanced space systems. Advancements in integrated multi-functional sensor systems, autonomous inspection approaches, distributed embedded sensors, roaming inspectors, and shape adaptive sensors are sought. Concepts in computational models for signal processing and data interpretation to establish quantitative characterization and event determination are also of interest. Prospective evaluation technologies include ultrasonics, laser ultrasonics, optics and fiber optics, shearography, video optics and metrology, thermography, electromagnetics, acoustic emission, x-ray, data management, biomimetics, and nano-scale sensing approaches for structural health monitoring.

Millimeter-wave imaging diagnostics systems on the EAST tokamak (invited)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhu, Y. L.; Xie, J. L., E-mail: jlxie@ustc.edu.cn; Yu, C. X.

2016-11-15

Millimeter-wave imaging diagnostics, with large poloidal span and wide radial range, have been developed on the EAST tokamak for visualization of 2D electron temperature and density fluctuations. A 384 channel (24 poloidal × 16 radial) Electron Cyclotron Emission Imaging (ECEI) system in F-band (90-140 GHz) was installed on the EAST tokamak in 2012 to provide 2D electron temperature fluctuation images with high spatial and temporal resolution. A co-located Microwave Imaging Reflectometry (MIR) will be installed for imaging of density fluctuations by December 2016. This “4th generation” MIR system has eight independent frequency illumination beams in W-band (75-110 GHz) driven bymore » fast tuning synthesizers and active multipliers. Both of these advanced millimeter-wave imaging diagnostic systems have applied the latest techniques. A novel design philosophy “general optics structure” has been employed for the design of the ECEI and MIR receiver optics with large aperture. The extended radial and poloidal coverage of ECEI on EAST is made possible by innovations in the design of front-end optics. The front-end optical structures of the two imaging diagnostics, ECEI and MIR, have been integrated into a compact system, including the ECEI receiver and MIR transmitter and receiver. Two imaging systems share the same mid-plane port for simultaneous, co-located 2D fluctuation measurements of electron density and temperature. An intelligent remote-control is utilized in the MIR electronics systems to maintain focusing at the desired radial region even with density variations by remotely tuning the probe frequencies in about 200 μs. A similar intelligent technique has also been applied on the ECEI IF system, with remote configuration of the attenuations for each channel.« less

Millimeter-wave imaging diagnostics systems on the EAST tokamak (invited)

NASA Astrophysics Data System (ADS)

Zhu, Y. L.; Xie, J. L.; Yu, C. X.; Zhao, Z. L.; Gao, B. X.; Chen, D. X.; Liu, W. D.; Liao, W.; Qu, C. M.; Luo, C.; Hu, X.; Spear, A. G.; Luhmann, N. C.; Domier, C. W.; Chen, M.; Ren, X.; Tobias, B. J.

2016-11-01

Millimeter-wave imaging diagnostics, with large poloidal span and wide radial range, have been developed on the EAST tokamak for visualization of 2D electron temperature and density fluctuations. A 384 channel (24 poloidal × 16 radial) Electron Cyclotron Emission Imaging (ECEI) system in F-band (90-140 GHz) was installed on the EAST tokamak in 2012 to provide 2D electron temperature fluctuation images with high spatial and temporal resolution. A co-located Microwave Imaging Reflectometry (MIR) will be installed for imaging of density fluctuations by December 2016. This "4th generation" MIR system has eight independent frequency illumination beams in W-band (75-110 GHz) driven by fast tuning synthesizers and active multipliers. Both of these advanced millimeter-wave imaging diagnostic systems have applied the latest techniques. A novel design philosophy "general optics structure" has been employed for the design of the ECEI and MIR receiver optics with large aperture. The extended radial and poloidal coverage of ECEI on EAST is made possible by innovations in the design of front-end optics. The front-end optical structures of the two imaging diagnostics, ECEI and MIR, have been integrated into a compact system, including the ECEI receiver and MIR transmitter and receiver. Two imaging systems share the same mid-plane port for simultaneous, co-located 2D fluctuation measurements of electron density and temperature. An intelligent remote-control is utilized in the MIR electronics systems to maintain focusing at the desired radial region even with density variations by remotely tuning the probe frequencies in about 200 μs. A similar intelligent technique has also been applied on the ECEI IF system, with remote configuration of the attenuations for each channel.

Microscopic Perspective on Photovoltaic Reciprocity in Ultrathin Solar Cells

NASA Astrophysics Data System (ADS)

Aeberhard, Urs; Rau, Uwe

2017-06-01

The photovoltaic reciprocity theory relates the electroluminescence spectrum of a solar cell under applied bias to the external photovoltaic quantum efficiency of the device as measured at short circuit conditions. Its derivation is based on detailed balance relations between local absorption and emission rates in optically isotropic media with nondegenerate quasiequilibrium carrier distributions. In many cases, the dependence of density and spatial variation of electronic and optical device states on the point of operation is modest and the reciprocity relation holds. In nanostructure-based photovoltaic devices exploiting confined modes, however, the underlying assumptions are no longer justifiable. In the case of ultrathin absorber solar cells, the modification of the electronic structure with applied bias is significant due to the large variation of the built-in field. Straightforward use of the external quantum efficiency as measured at short circuit conditions in the photovoltaic reciprocity theory thus fails to reproduce the electroluminescence spectrum at large forward bias voltage. This failure is demonstrated here by numerical simulation of both spectral quantities at normal incidence and emission for an ultrathin GaAs p -i -n solar cell using an advanced quantum kinetic formalism based on nonequilibrium Green's functions of coupled photons and charge carriers. While coinciding with the semiclassical relations under the conditions of their validity, the theory provides a consistent microscopic relationship between absorption, emission, and charge carrier transport in photovoltaic devices at arbitrary operating conditions and for any shape of optical and electronic density of states.

Microscopic Perspective on Photovoltaic Reciprocity in Ultrathin Solar Cells.

PubMed

Aeberhard, Urs; Rau, Uwe

2017-06-16

The photovoltaic reciprocity theory relates the electroluminescence spectrum of a solar cell under applied bias to the external photovoltaic quantum efficiency of the device as measured at short circuit conditions. Its derivation is based on detailed balance relations between local absorption and emission rates in optically isotropic media with nondegenerate quasiequilibrium carrier distributions. In many cases, the dependence of density and spatial variation of electronic and optical device states on the point of operation is modest and the reciprocity relation holds. In nanostructure-based photovoltaic devices exploiting confined modes, however, the underlying assumptions are no longer justifiable. In the case of ultrathin absorber solar cells, the modification of the electronic structure with applied bias is significant due to the large variation of the built-in field. Straightforward use of the external quantum efficiency as measured at short circuit conditions in the photovoltaic reciprocity theory thus fails to reproduce the electroluminescence spectrum at large forward bias voltage. This failure is demonstrated here by numerical simulation of both spectral quantities at normal incidence and emission for an ultrathin GaAs p-i-n solar cell using an advanced quantum kinetic formalism based on nonequilibrium Green's functions of coupled photons and charge carriers. While coinciding with the semiclassical relations under the conditions of their validity, the theory provides a consistent microscopic relationship between absorption, emission, and charge carrier transport in photovoltaic devices at arbitrary operating conditions and for any shape of optical and electronic density of states.

WDM package enabling high-bandwidth optical intrasystem interconnects for high-performance computer systems

NASA Astrophysics Data System (ADS)

Schrage, J.; Soenmez, Y.; Happel, T.; Gubler, U.; Lukowicz, P.; Mrozynski, G.

2006-02-01

From long haul, metro access and intersystem links the trend goes to applying optical interconnection technology at increasingly shorter distances. Intrasystem interconnects such as data busses between microprocessors and memory blocks are still based on copper interconnects today. This causes a bottleneck in computer systems since the achievable bandwidth of electrical interconnects is limited through the underlying physical properties. Approaches to solve this problem by embedding optical multimode polymer waveguides into the board (electro-optical circuit board technology, EOCB) have been reported earlier. The principle feasibility of optical interconnection technology in chip-to-chip applications has been validated in a number of projects. For reasons of cost considerations waveguides with large cross sections are used in order to relax alignment requirements and to allow automatic placement and assembly without any active alignment of components necessary. On the other hand the bandwidth of these highly multimodal waveguides is restricted due to mode dispersion. The advance of WDM technology towards intrasystem applications will provide sufficiently high bandwidth which is required for future high-performance computer systems: Assuming that, for example, 8 wavelength-channels with 12Gbps (SDR1) each are given, then optical on-board interconnects with data rates a magnitude higher than the data rates of electrical interconnects for distances typically found at today's computer boards and backplanes can be realized. The data rate will be twice as much, if DDR2 technology is considered towards the optical signals as well. In this paper we discuss an approach for a hybrid integrated optoelectronic WDM package which might enable the application of WDM technology to EOCB.

Optical filter finesses enhancement based on nested coupled cavities and active medium

NASA Astrophysics Data System (ADS)

Adib, George A.; Sabry, Yasser M.; Khalil, Diaa

2016-04-01

Optical filters with relatively large FSR and narrow linewidth are simultaneously needed for different applications. The ratio between the FSR and the 3-dB linewidth is given by finesse of the filter, which is solely determined by the different energy loss mechanisms limited by the technology advancement. In this work, we present a novel coupled-cavity configuration embedding an optical filter and a gain medium; allowing an overall finesse enhancement and simultaneous FSR and 3-dB linewidth engineering beyond the technological limits of the filter fabrication method. The configuration consists of two resonators. An active ring resonator comprises an optical gain medium and a passive resonator. In one configuration, the optical filter is the passive resonator itself. In a second configuration, the passive resonator is another ring resonator that embeds the optical filter. The presented configurations using a semiconductor optical amplifier are applied one time to a mechanically Fabry-Perot filter in the first presented configuration; and a second time to a fiber ring filter in the second presented configuration. The mechanical filter has an original 3-dB linewidth of 1nm and an FSR that is larger than 100nm while the enhanced linewidth is about 0.3nm. The fiber ring filter length is 4 m and directional coupler ratios of 90/10corresponding to a 3-dBlinewidth of about 4MHz and an FSR of 47 MHz. The enhanced 3- dBlinewidth of the overall filter configuration is 200kHz, demonstrating finesse enhancement up to20 times the original finesse of the filter.

Optical fiber voltage sensor based on Michelsion interferometer using Fabry-Perot demodulation interferometer

NASA Astrophysics Data System (ADS)

Chen, Xinwei; He, Shengnan; Li, Dandan; Wang, Kai; Fan, Yan'en; Wu, Shuai

2014-11-01

We present an optical fiber voltage sensor by Michelsion interferometer (MI) employing a Fabry-Perot (F-P) interferometer and the DC phase tracking (DCPT) signal processing method. By mounting a MI fabricated by an optical fiber coupler on a piezoelectric (PZT) transducer bar, a dynamic strain would be generated to change the optical path difference (OPD) of the interferometer when the measured voltage was applied on the PZT. Applying an F-P interferometer to demodulate the optical intensity variation output of the MI, the voltage can be obtained. The experiment results show that the relationship between the optical intensity variation and the voltage applied on the PZT is approximately linear. Furthermore, the phase generate carrier (PGC) algorithm was applied to demodulate the output of the sensor also.

A novel dual-detector micro-spectrometer

NASA Astrophysics Data System (ADS)

Otto, Thomas; Saupe, Ray; Stock, Volker; Bruch, Reinhard; Gruska, Bernd; Gessner, Thomas

2005-01-01

Infrared analysis is a well-established tool for measuring composition and purity of various materials in industrial-, medical- and environmental applications. Traditional spectrometers, for example Fourier Transform Infrared (FTIR) Instruments are mainly designed for laboratory use and are generally, too large, heavy, costly and delicate to handle for remote applications. With important advances in the miniaturization, ruggedness and cost efficiency we have designed and created a new type of a micromirror spectrometer that can operate in harsh temperature and vibrating environments This device is ideally suited for environmental monitoring, chemical and biological applications as well as detection of biological warfare agents and sensing in important security locations In order to realize such compact, portable and field-deployable spectrometers we have applied MOEMS technology. Thus our novel dual detector micro mirror system is composed of a scanning micro mirror combined with a diffraction grating and other essential optical components in order to miniaturize the basic modular set-up. Especially it periodically disperses polychromatic radiation into its spectral components, which are measured by a combination of a visible (VIS) and near infrared (NIR) single element detector. By means of integrated preamplifiers high-precise measurements over a wide dynamic wavelength range are possible. In addition the spectrometer, including the radiation source, detectors and electronics can be coupled to a minimum-volume liquid or gas-flow cell. Furthermore a SMA connector as a fiber optical input allows easy attachment of fiber based probes. By utilizing rapid prototyping techniques, where all components are directly integrated, the micro mirror spectrometer is manufactured for the 700-1700 nm spectral range. In this work the advanced optical design and integration of the electronic interface will be reviewed. Furthermore we will demonstrate the performance of the system and present characteristic measurement results. Finally advanced packaging issues and test results of the device will be discussed.

Functionalization and Characterization of Nanomaterial Gated Field-Effect Transistor-Based Biosensors and the Design of a Multi-Analyte Implantable Biosensing Platform

NASA Astrophysics Data System (ADS)

Croce, Robert A., Jr.

Advances in semiconductor research and complementary-metal-oxide semiconductor fabrication allow for the design and implementation of miniaturized metabolic monitoring systems, as well as advanced biosensor design. The first part of this dissertation will focus on the design and fabrication of nanomaterial (single-walled carbon nanotube and quantum dot) gated field-effect transistors configured as protein sensors. These novel device structures have been functionalized with single-stranded DNA aptamers, and have shown sensor operation towards the protein Thrombin. Such advanced transistor-based sensing schemes present considerable advantages over traditional sensing methodologies in view of its miniaturization, low cost, and facile fabrication, paving the way for the ultimate realization of a multi-analyte lab-on-chip. The second part of this dissertation focuses on the design and fabrication of a needle-implantable glucose sensing platform which is based solely on photovoltaic powering and optical communication. By employing these powering and communication schemes, this design negates the need for bulky on-chip RF-based transmitters and batteries in an effort to attain extreme miniaturization required for needle-implantable/extractable applications. A complete single-sensor system coupled with a miniaturized amperometric glucose sensor has been demonstrated to exhibit reality of this technology. Furthermore, an optical selection scheme of multiple potentiostats for four different analytes (glucose, lactate, O 2 and CO2) as well as the optical transmission of sensor data has been designed for multi-analyte applications. The last part of this dissertation will focus on the development of a computational model for the amperometric glucose sensors employed in the aforementioned implantable platform. This model has been applied to single-layer single-enzyme systems, as well as multi-layer (single enzyme) systems utilizing glucose flux limiting layer-by-layer assembled outer membranes. The concentration of glucose and hydrogen peroxide within the sensor geometry, the transient response and the device response time has been simulated for both systems.

Finite Element Modeling of a Semi-Rigid Hybrid Mirror and a Highly Actuated Membrane Mirror as Candidates for the Next Generation Space Telescope

NASA Technical Reports Server (NTRS)

Craig, Larry; Jacobson, Dave; Mosier, Gary; Nein, Max; Page, Timothy; Redding, Dave; Sutherlin, Steve; Wilkerson, Gary

2000-01-01

Advanced space telescopes, which will eventually replace the Hubble Space Telescope (HTS), will have apertures of 8 - 20 n. Primary mirrors of these dimensions will have to be foldable to fit into the space launcher. By necessity these mirrors will be extremely light weight and flexible and the historical approaches to mirror designs, where the mirror is made as rigid as possible to maintain figure and to serve as the anchor for the entire telescope, cannot be applied any longer. New design concepts and verifications will depend entirely on analytical methods to predict optical performance. Finite element modeling of the structural and thermal behavior of such mirrors is becoming the tool for advanced space mirror designs. This paper discusses some of the preliminary tasks and study results, which are currently the basis for the design studies of the Next Generation Space Telescope.

Multidimensional Processing and Visual Rendering of Complex 3D Biomedical Images

NASA Technical Reports Server (NTRS)

Sams, Clarence F.

2016-01-01

The proposed technology uses advanced image analysis techniques to maximize the resolution and utility of medical imaging methods being used during spaceflight. We utilize COTS technology for medical imaging, but our applications require higher resolution assessment of the medical images than is routinely applied with nominal system software. By leveraging advanced data reduction and multidimensional imaging techniques utilized in analysis of Planetary Sciences and Cell Biology imaging, it is possible to significantly increase the information extracted from the onboard biomedical imaging systems. Year 1 focused on application of these techniques to the ocular images collected on ground test subjects and ISS crewmembers. Focus was on the choroidal vasculature and the structure of the optic disc. Methods allowed for increased resolution and quantitation of structural changes enabling detailed assessment of progression over time. These techniques enhance the monitoring and evaluation of crew vision issues during space flight.

Established Designs For Advanced Ground Based Astronomical Telescopes In The 1-meter To 4-meter Domain

NASA Astrophysics Data System (ADS)

Hull, Anthony B.; Barentine, J.; Legters, S.

2012-01-01

The same technology and analytic approaches that led to cost-effective unmitigated successes for the spaceborne Kepler and WISE telescopes are now being applied to meter-class to 4-meter-class ground telescopes, providing affordable solutions to ground astronomy, with advanced features as needed for the application. The range of optical and mechanical performance standards and features that can be supplied for ground astronomy shall be described. Both classical RC designs, as well as unobscured designs are well represented in the IOS design library, allowing heritage designs for both night time and day time operations, the latter even in the proximity of the sun. In addition to discussing this library of mature features, we will also describe a process for working with astronomers early in the definition process to provide the best-value solution. Solutions can include remote operation and astronomical data acquisition and transmission.

Combined Advanced Finishing and UV-Laser Conditioning for Producing UV-Damage-Resistant Fused Silica Optics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Menapace, J A; Penetrante, B; Golini, D

2001-11-01

Laser induced damage initiation on fused silica optics can limit the lifetime of the components when used in high power UV laser environments. Foe example in inertial confinement fusion research applications, the optics can be exposed to temporal laser pulses of about 3-nsec with average fluences of 8 J/cm{sup 2} and peak fluences between 12 and 15 J/cm{sup 2}. During the past year, we have focused on optimizing the damage performance at a wavelength of 355-nm (3{omega}), 3-nsec pulse length, for optics in this category by examining a variety of finishing technologies with a challenge to improve the laser damagemore » initiation density by at least two orders of magnitude. In this paper, we describe recent advances in improving the 3{omega} damage initiation performance of laboratory-scale zirconium oxide and cerium oxide conventionally finished fused silica optics via application of processes incorporating magnetorheological finishing (MRF), wet chemical etching, and UV laser conditioning. Details of the advanced finishing procedures are described and comparisons are made between the procedures based upon large area 3{omega} damage performance, polishing layer contamination, and optical subsurface damage.« less

Signal processing for molecular and cellular biological physics: an emerging field.

PubMed

Little, Max A; Jones, Nick S

2013-02-13

Recent advances in our ability to watch the molecular and cellular processes of life in action--such as atomic force microscopy, optical tweezers and Forster fluorescence resonance energy transfer--raise challenges for digital signal processing (DSP) of the resulting experimental data. This article explores the unique properties of such biophysical time series that set them apart from other signals, such as the prevalence of abrupt jumps and steps, multi-modal distributions and autocorrelated noise. It exposes the problems with classical linear DSP algorithms applied to this kind of data, and describes new nonlinear and non-Gaussian algorithms that are able to extract information that is of direct relevance to biological physicists. It is argued that these new methods applied in this context typify the nascent field of biophysical DSP. Practical experimental examples are supplied.

Signal processing for molecular and cellular biological physics: an emerging field

PubMed Central

Little, Max A.; Jones, Nick S.

2013-01-01

Recent advances in our ability to watch the molecular and cellular processes of life in action—such as atomic force microscopy, optical tweezers and Forster fluorescence resonance energy transfer—raise challenges for digital signal processing (DSP) of the resulting experimental data. This article explores the unique properties of such biophysical time series that set them apart from other signals, such as the prevalence of abrupt jumps and steps, multi-modal distributions and autocorrelated noise. It exposes the problems with classical linear DSP algorithms applied to this kind of data, and describes new nonlinear and non-Gaussian algorithms that are able to extract information that is of direct relevance to biological physicists. It is argued that these new methods applied in this context typify the nascent field of biophysical DSP. Practical experimental examples are supplied. PMID:23277603

Ultra-Wideband Optical Modulation Spectrometer (OMS) Development: Study of the Optical Setup of a Wide-Band Optical Modulation Spectrometer

NASA Technical Reports Server (NTRS)

Tolls, Volker; Stringfellow, Guy (Technical Monitor)

2001-01-01

The purpose of this study is to advance the design of the optical setup for a wide-band Optical Modulation Spectrometer (OMS) for use with astronomical heterodyne receiver systems. This report describes the progress of this investigation achieved from March until December 2001.

Advances in optical structure systems; Proceedings of the Meeting, Orlando, FL, Apr. 16-19, 1990

NASA Astrophysics Data System (ADS)

Breakwell, John; Genberg, Victor L.; Krumweide, Gary C.

Various papers on advances in optical structure systems are presented. Individual topics addressed include: beam pathlength optimization, thermal stress in glass/metal bond with PR 1578 adhesive, structural and optical properties for typical solid mirror shapes, parametric study of spinning polygon mirror deformations, simulation of small structures-optics-controls system, spatial PSDs of optical structures due to random vibration, mountings for a four-meter glass mirror, fast-steering mirrors in optical control systems, adaptive state estimation for control of flexible structures, surface control techniques for large segmented mirrors, two-time-scale control designs for large flexible structures, closed-loop dynamic shape control of a flexible beam. Also discussed are: inertially referenced pointing for body-fixed payloads, sensor blending line-of-sight stabilization, controls/optics/structures simulation development, transfer functions for piezoelectric control of a flexible beam, active control experiments for large-optics vibration alleviation, composite structures for a large-optical test bed, graphite/epoxy composite mirror for beam-steering applications, composite structures for optical-mirror applications, thin carbon-fiber prepregs for dimensionally critical structures.

Large Electro-Optic Kerr Effect in Ionic Liquid Crystals: Connecting Features of Liquid Crystals and Polyelectrolytes.

PubMed

Schlick, M Christian; Kapernaum, Nadia; Neidhardt, Manuel M; Wöhrle, Tobias; Stöckl, Yannick; Laschat, Sabine; Giesselmann, Frank

2018-06-06

The electro-optic Kerr effect in simple dipolar fluids such as nitrobenzene has been widely applied in electro-optical phase modulators and light shutters. In 2005, the discovery of the large Kerr effect in liquid-crystalline blue phases (Y. Hisakado et al., Adv. Mater. 2005, 17, 96-98.) gave new directions to the search for advanced Kerr effect materials. Even though the Kerr effect is present in all transparent and optically isotropic media, it is well known that the effect can be anomalously large in complex fluids, namely in the isotropic phase of liquid crystals or in polyelectrolyte solutions. Herein, it is shown that the Kerr effect in the isotropic phase of ionic liquid crystals combines the effective counterion polarization mechanism found in polyelectrolytes and the unique pretransitional growth of the Kerr constant found in the isotropic phase of nematic liquid crystals. Maximum Kerr constants in the order of several 10 -11  m V -2 (ten times higher than the Kerr constant of the toxic nitrobenzene and less temperature sensitive than Kerr constants of nematic liquid crystals) make ionic liquid crystals attractive as new class of functional materials in low-speed Kerr effect applications. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Optical performance of a PDMS tunable lens with automatically controlled applied stress

NASA Astrophysics Data System (ADS)

Cruz-Felix, Angel S.; Santiago-Alvarado, Agustín.; Hernández-Méndez, Arturo; Reyes-Pérez, Emilio R.; Tepichín-Rodriguez, Eduardo

2016-09-01

The advances in the field of adaptive optics and in the fabrication of tunable optical components capable to automatically modify their physical features are of great interest in areas like machine vision, imaging systems, ophthalmology, etc. Such components like tunable lenses are used to reduce the overall size of optical setups like in small camera systems and even to imitate some biological functions made by the human eye. In this direction, in the last years we have been working in the development and fabrication of PDMS-made tunable lenses and in the design of special mechanical mounting systems to manipulate them. A PDMS-made tunable lens was previously designed by us, following the scheme reported by Navarro et al. in 1985, in order to mimic the accommodation process made by the crystalline lens of the human eye. The design included a simulation of the application of radial stress onto the lens and it was shown that the effective focal length was indeed changed. In this work we show the fabrication process of this particular tunable lens and an optimized mechanism that is able to automatically change the curvature of both surfaces of the lens by the application of controlled stress. We also show results of a study and analysis of aberrations performed to the Solid Elastic Lens (SEL).

Planar Diffractive Lenses: Fundamentals, Functionalities, and Applications.

PubMed

Huang, Kun; Qin, Fei; Liu, Hong; Ye, Huapeng; Qiu, Cheng-Wei; Hong, Minghui; Luk'yanchuk, Boris; Teng, Jinghua

2018-06-01

Traditional objective lenses in modern microscopy, based on the refraction of light, are restricted by the Rayleigh diffraction limit. The existing methods to overcome this limit can be categorized into near-field (e.g., scanning near-field optical microscopy, superlens, microsphere lens) and far-field (e.g., stimulated emission depletion microscopy, photoactivated localization microscopy, stochastic optical reconstruction microscopy) approaches. However, they either operate in the challenging near-field mode or there is the need to label samples in biology. Recently, through manipulation of the diffraction of light with binary masks or gradient metasurfaces, some miniaturized and planar lenses have been reported with intriguing functionalities such as ultrahigh numerical aperture, large depth of focus, and subdiffraction-limit focusing in far-field, which provides a viable solution for the label-free superresolution imaging. Here, the recent advances in planar diffractive lenses (PDLs) are reviewed from a united theoretical account on diffraction-based focusing optics, and the underlying physics of nanofocusing via constructive or destructive interference is revealed. Various approaches of realizing PDLs are introduced in terms of their unique performances and interpreted by using optical aberration theory. Furthermore, a detailed tutorial about applying these planar lenses in nanoimaging is provided, followed by an outlook regarding future development toward practical applications. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Development of a standardized differential-reflective bioassay for microbial pathogens

NASA Astrophysics Data System (ADS)

Wilhelm, Jay; Auld, J. R. X.; Smith, James E.

2008-04-01

This research examines standardizing a method for the rapid/semi-automated identification of microbial contaminates. It introduces a method suited to test for food/water contamination, serology, urinalysis and saliva testing for any >1 micron sized molecule that can be effectively bound to an identifying marker with exclusivity. This optical biosensor method seeks to integrate the semi-manual distribution of a collected sample onto a "transparent" substrate array of binding sites that will then be applied to a standard optical data disk and run for analysis. The detection of most microbe species is possible in this platform because the relative scale is greater than the resolution of the standard-scale digital information on a standard CD or DVD. This paper explains the critical first stage in the advance of this detection concept. This work has concentrated on developing the necessary software component needed to perform highly sensitive small-scale recognition using the standard optical disk as a detection platform. Physical testing has made significant progress in demonstrating the ability to utilize a standard optical drive for the purposes of micro-scale detection through the exploitation of CIRC error correction. Testing has also shown a definable trend in the optimum scale and geometry of micro-arrayed attachment sites for the technology's concept to reach achievement.

Diagnostics of the Fermilab Tevatron using an AC dipole

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miyamoto, Ryoichi

2008-08-01

The Fermilab Tevatron is currently the world's highest energy colliding beam facility. Its counter-rotating proton and antiproton beams collide at 2 TeV center-of-mass. Delivery of such intense beam fluxes to experiments has required improved knowledge of the Tevatron's beam optical lattice. An oscillating dipole magnet, referred to as an AC dipole, is one of such a tool to non-destructively assess the optical properties of the synchrotron. We discusses development of an AC dipole system for the Tevatron, a fast-oscillating (f ~ 20 kHz) dipole magnet which can be adiabatically turned on and off to establish sustained coherent oscillations of themore » beam particles without affecting the transverse emittance. By utilizing an existing magnet and a higher power audio amplifier, the cost of the Tevatron AC dipole system became relatively inexpensive. We discuss corrections which must be applied to the driven oscillation measurements to obtain the proper interpretation of beam optical parameters from AC dipole studies. After successful operations of the Tevatron AC dipole system, AC dipole systems, similar to that in the Tevatron, will be build for the CERN LHC. We present several measurements of linear optical parameters (beta function and phase advance) for the Tevatron, as well as studies of non-linear perturbations from sextupole and octupole elements.« less

Extragalactic SETI: The Tully-Fisher Relation as a Probe of Dysonian Astroengineering in Disk Galaxies

NASA Astrophysics Data System (ADS)

Zackrisson, Erik; Calissendorff, Per; Asadi, Saghar; Nyholm, Anders

2015-09-01

If advanced extraterrestrial civilizations choose to construct vast numbers of Dyson spheres to harvest radiation energy, this could affect the characteristics of their host galaxies. Potential signatures of such astroengineering projects include reduced optical luminosity, boosted infrared luminosity, and morphological anomalies. Here, we apply a technique pioneered by Annis to search for Kardashev type III civilizations in disk galaxies, based on the predicted offset of these galaxies from the optical Tully-Fisher (TF) relation. By analyzing a sample of 1359 disk galaxies, we are able to set a conservative upper limit of ≲ 3% on the fraction of local disks subject to Dysonian astroengineering on galaxy-wide scales. However, the available data suggests that a small subset of disk galaxies actually may be underluminous with respect to the TF relation in the way expected for Kardashev type III objects. Based on the optical morphologies and infrared-to-optical luminosity ratios of such galaxies in our sample, we conclude that none of them stand out as strong Kardashev type III candidates and that their inferred properties likely have mundane explanations. This allows us to set a tentative upper limit at ≲ 0.3% on the fraction of Karashev type III disk galaxies in the local universe.

Optics of high-performance electron microscopes*

PubMed Central

Rose, H H

2008-01-01

During recent years, the theory of charged particle optics together with advances in fabrication tolerances and experimental techniques has lead to very significant advances in high-performance electron microscopes. Here, we will describe which theoretical tools, inventions and designs have driven this development. We cover the basic theory of higher-order electron optics and of image formation in electron microscopes. This leads to a description of different methods to correct aberrations by multipole fields and to a discussion of the most advanced design that take advantage of these techniques. The theory of electron mirrors is developed and it is shown how this can be used to correct aberrations and to design energy filters. Finally, different types of energy filters are described. PMID:27877933

Space Optics for the 21st Century

NASA Technical Reports Server (NTRS)

Bilbro, James W.

2006-01-01

Technological advances over the last decade in metrology, fabrication techniques and materials have made a significant impact on spacebased astronomy and together with advances in adaptive optics offer the opportunity for even more radical changes in the future. The Hubble Space Telescope primary mirror is 2.4 meters in diameter and weighs on the order of 150 kilograms per square meter. The technology demonstration mirrors developed for the James Webb Telescope had an order of magnitude less in area density and developments in membrane optics offer the opportunity to achieve another order of magnitude decrease. Similar advances in mirrors for x-ray astronomy means that across the spectrum future space based telescopes will have greater and greater collecting areas with ever increasing resolution.

Peptide Integrated Optics.

PubMed

Handelman, Amir; Lapshina, Nadezda; Apter, Boris; Rosenman, Gil

2018-02-01

Bio-nanophotonics is a wide field in which advanced optical materials, biomedicine, fundamental optics, and nanotechnology are combined and result in the development of biomedical optical chips. Silk fibers or synthetic bioabsorbable polymers are the main light-guiding components. In this work, an advanced concept of integrated bio-optics is proposed, which is based on bioinspired peptide optical materials exhibiting wide optical transparency, nonlinear and electrooptical properties, and effective passive and active waveguiding. Developed new technology combining bottom-up controlled deposition of peptide planar wafers of a large area and top-down focus ion beam lithography provides direct fabrication of peptide optical integrated circuits. Finding a deep modification of peptide optical properties by reconformation of biological secondary structure from native phase to β-sheet architecture is followed by the appearance of visible fluorescence and unexpected transition from a native passive optical waveguiding to an active one. Original biocompatibility, switchable regimes of waveguiding, and multifunctional nonlinear optical properties make these new peptide planar optical materials attractive for application in emerging technology of lab-on-biochips, combining biomedical photonic and electronic circuits toward medical diagnosis, light-activated therapy, and health monitoring. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Graphene-Boron Nitride Heterostructure Based Optoelectronic Devices for On-Chip Optical Interconnects

NASA Astrophysics Data System (ADS)

Gao, Yuanda

Graphene has emerged as an appealing material for a variety of optoelectronic applications due to its unique electrical and optical characteristics. In this thesis, I will present recent advances in integrating graphene and graphene-boron nitride (BN) heterostructures with confined optical architectures, e.g. planar photonic crystal (PPC) nanocavities and silicon channel waveguides, to make this otherwise weakly absorbing material optically opaque. Based on these integrations, I will further demonstrate the resulting chip-integrated optoelectronic devices for optical interconnects. After transferring a layer of graphene onto PPC nanocavities, spectral selectivity at the resonance frequency and orders-of-magnitude enhancement of optical coupling with graphene have been observed in infrared spectrum. By applying electrostatic potential to graphene, electro-optic modulation of the cavity reflection is possible with contrast in excess of 10 dB. And furthermore, a novel and complex modulator device structure based on the cavity-coupled and BN-encapsulated dual-layer graphene capacitor is demonstrated to operate at a speed of 1.2 GHz. On the other hand, an enhanced broad-spectrum light-graphene interaction coupled with silicon channel waveguides is also demonstrated with ?0.1 dB/?m transmission attenuation due to graphene absorption. A waveguide-integrated graphene photodetector is fabricated and shown 0.1 A/W photoresponsivity and 20 GHz operation speed. An improved version of a similar photodetector using graphene-BN heterostructure exhibits 0.36 A/W photoresponsivity and 42 GHz response speed. The integration of graphene and graphene-BN heterostructures with nanophotonic architectures promises a new generation of compact, energy-efficient, high-speed optoelectronic device concepts for on-chip optical communications that are not yet feasible or very difficult to realize using traditional bulk semiconductors.

Advanced Spatial-Division Multiplexed Measurement Systems Propositions—From Telecommunication to Sensing Applications: A Review

PubMed Central

Weng, Yi; Ip, Ezra; Pan, Zhongqi; Wang, Ting

2016-01-01

The concepts of spatial-division multiplexing (SDM) technology were first proposed in the telecommunications industry as an indispensable solution to reduce the cost-per-bit of optical fiber transmission. Recently, such spatial channels and modes have been applied in optical sensing applications where the returned echo is analyzed for the collection of essential environmental information. The key advantages of implementing SDM techniques in optical measurement systems include the multi-parameter discriminative capability and accuracy improvement. In this paper, to help readers without a telecommunication background better understand how the SDM-based sensing systems can be incorporated, the crucial components of SDM techniques, such as laser beam shaping, mode generation and conversion, multimode or multicore elements using special fibers and multiplexers are introduced, along with the recent developments in SDM amplifiers, opto-electronic sources and detection units of sensing systems. The examples of SDM-based sensing systems not only include Brillouin optical time-domain reflectometry or Brillouin optical time-domain analysis (BOTDR/BOTDA) using few-mode fibers (FMF) and the multicore fiber (MCF) based integrated fiber Bragg grating (FBG) sensors, but also involve the widely used components with their whole information used in the full multimode constructions, such as the whispering gallery modes for fiber profiling and chemical species measurements, the screw/twisted modes for examining water quality, as well as the optical beam shaping to improve cantilever deflection measurements. Besides, the various applications of SDM sensors, the cost efficiency issue, as well as how these complex mode multiplexing techniques might improve the standard fiber-optic sensor approaches using single-mode fibers (SMF) and photonic crystal fibers (PCF) have also been summarized. Finally, we conclude with a prospective outlook for the opportunities and challenges of SDM technologies in optical sensing industry. PMID:27589754

Innovative materials tailored for advanced micro-optic applications

NASA Astrophysics Data System (ADS)

Himmelhuber, Roland; Fink, Marion; Pfeiffer, Karl; Ostrzinski, Ute; Klukowska, Anna; Gruetzner, Gabi; Houbertz, Ruth; Wolter, Herbert

2007-02-01

The handling of a continuously increasing amount of data leads to a strong need for high-speed short-range connections. Conventional Cu technology between chips on a board is limited. Optical interconnects will dominate the market, since they can overcome the limitations. One of the issues for materials used, e.g., for waveguides embedded in printed circuit boards (PCBs) is the compatibility with standard epoxies used for PCBs during the entire board fabrication process. Materials applied for optical interconnects should be mechanically and optically reliable, and also allow low-cost production. From the material production side, the process should be easy to up-scale. Therefore, anticipatory research strategy and suitable tailoring is asked for. The handling of light in the UV and visible range often requires the use of specially designed materials. Most polymer materials show an increased yellowing effect upon being exposed to shorter wavelength light. The major influence on the absorption in the UV and visible range of a UV curable material is related to the UV initiator, beside any other chromophores formed mainly during the exposure. Different material approaches will be presented which fulfil the requirements for highly sophisticated applications in optics / optical packaging technology. Firstly, an epoxy-based material system for optical chip-to-chip interconnection will be introduced. Secondly, the adaptation of a UV patternable inorganic-organic hybrid material (ORMOCER ®) originally developed for waveguide applications in the data and telecom regime, will be discussed with respect to applications in the visible regime. Spectroscopy and UV-DSC measurements were carried out to investigate the influence of standard photoinitiators on the optical properties for an ORMOCER ® system suitable for microoptic applications. The results show that the resulting material properties were significantly improved by exchange of the initiators compared to the originally incorporated one.

Seeing through Musculoskeletal Tissues: Improving In Situ Imaging of Bone and the Lacunar Canalicular System through Optical Clearing

PubMed Central

Berke, Ian M.; Miola, Joseph P.; David, Michael A.; Smith, Melanie K.; Price, Christopher

2016-01-01

In situ, cells of the musculoskeletal system reside within complex and often interconnected 3-D environments. Key to better understanding how 3-D tissue and cellular environments regulate musculoskeletal physiology, homeostasis, and health is the use of robust methodologies for directly visualizing cell-cell and cell-matrix architecture in situ. However, the use of standard optical imaging techniques is often of limited utility in deep imaging of intact musculoskeletal tissues due to the highly scattering nature of biological tissues. Drawing inspiration from recent developments in the deep-tissue imaging field, we describe the application of immersion based optical clearing techniques, which utilize the principle of refractive index (RI) matching between the clearing/mounting media and tissue under observation, to improve the deep, in situ imaging of musculoskeletal tissues. To date, few optical clearing techniques have been applied specifically to musculoskeletal tissues, and a systematic comparison of the clearing ability of optical clearing agents in musculoskeletal tissues has yet to be fully demonstrated. In this study we tested the ability of eight different aqueous and non-aqueous clearing agents, with RIs ranging from 1.45 to 1.56, to optically clear murine knee joints and cortical bone. We demonstrated and quantified the ability of these optical clearing agents to clear musculoskeletal tissues and improve both macro- and micro-scale imaging of musculoskeletal tissue across several imaging modalities (stereomicroscopy, spectroscopy, and one-, and two-photon confocal microscopy) and investigational techniques (dynamic bone labeling and en bloc tissue staining). Based upon these findings we believe that optical clearing, in combination with advanced imaging techniques, has the potential to complement classical musculoskeletal analysis techniques; opening the door for improved in situ investigation and quantification of musculoskeletal tissues. PMID:26930293

Seeing through Musculoskeletal Tissues: Improving In Situ Imaging of Bone and the Lacunar Canalicular System through Optical Clearing.

PubMed

Berke, Ian M; Miola, Joseph P; David, Michael A; Smith, Melanie K; Price, Christopher

2016-01-01

In situ, cells of the musculoskeletal system reside within complex and often interconnected 3-D environments. Key to better understanding how 3-D tissue and cellular environments regulate musculoskeletal physiology, homeostasis, and health is the use of robust methodologies for directly visualizing cell-cell and cell-matrix architecture in situ. However, the use of standard optical imaging techniques is often of limited utility in deep imaging of intact musculoskeletal tissues due to the highly scattering nature of biological tissues. Drawing inspiration from recent developments in the deep-tissue imaging field, we describe the application of immersion based optical clearing techniques, which utilize the principle of refractive index (RI) matching between the clearing/mounting media and tissue under observation, to improve the deep, in situ imaging of musculoskeletal tissues. To date, few optical clearing techniques have been applied specifically to musculoskeletal tissues, and a systematic comparison of the clearing ability of optical clearing agents in musculoskeletal tissues has yet to be fully demonstrated. In this study we tested the ability of eight different aqueous and non-aqueous clearing agents, with RIs ranging from 1.45 to 1.56, to optically clear murine knee joints and cortical bone. We demonstrated and quantified the ability of these optical clearing agents to clear musculoskeletal tissues and improve both macro- and micro-scale imaging of musculoskeletal tissue across several imaging modalities (stereomicroscopy, spectroscopy, and one-, and two-photon confocal microscopy) and investigational techniques (dynamic bone labeling and en bloc tissue staining). Based upon these findings we believe that optical clearing, in combination with advanced imaging techniques, has the potential to complement classical musculoskeletal analysis techniques; opening the door for improved in situ investigation and quantification of musculoskeletal tissues.

Advanced Spatial-Division Multiplexed Measurement Systems Propositions-From Telecommunication to Sensing Applications: A Review.

PubMed

Weng, Yi; Ip, Ezra; Pan, Zhongqi; Wang, Ting

2016-08-30

The concepts of spatial-division multiplexing (SDM) technology were first proposed in the telecommunications industry as an indispensable solution to reduce the cost-per-bit of optical fiber transmission. Recently, such spatial channels and modes have been applied in optical sensing applications where the returned echo is analyzed for the collection of essential environmental information. The key advantages of implementing SDM techniques in optical measurement systems include the multi-parameter discriminative capability and accuracy improvement. In this paper, to help readers without a telecommunication background better understand how the SDM-based sensing systems can be incorporated, the crucial components of SDM techniques, such as laser beam shaping, mode generation and conversion, multimode or multicore elements using special fibers and multiplexers are introduced, along with the recent developments in SDM amplifiers, opto-electronic sources and detection units of sensing systems. The examples of SDM-based sensing systems not only include Brillouin optical time-domain reflectometry or Brillouin optical time-domain analysis (BOTDR/BOTDA) using few-mode fibers (FMF) and the multicore fiber (MCF) based integrated fiber Bragg grating (FBG) sensors, but also involve the widely used components with their whole information used in the full multimode constructions, such as the whispering gallery modes for fiber profiling and chemical species measurements, the screw/twisted modes for examining water quality, as well as the optical beam shaping to improve cantilever deflection measurements. Besides, the various applications of SDM sensors, the cost efficiency issue, as well as how these complex mode multiplexing techniques might improve the standard fiber-optic sensor approaches using single-mode fibers (SMF) and photonic crystal fibers (PCF) have also been summarized. Finally, we conclude with a prospective outlook for the opportunities and challenges of SDM technologies in optical sensing industry.

Optics and lasers: A compilation

NASA Technical Reports Server (NTRS)

1976-01-01

A number of innovative devices and techniques in optics and related fields were presented. The following areas were covered: advances in laser and holography technology, articles on spectroscopy and general optics, new information in the area of photography.

Applied Impact Physics Research

NASA Astrophysics Data System (ADS)

Wickert, Matthias

2013-06-01

Applied impact physics research is based on the capability to examine impact processes for a wide range of impact conditions with respect to velocity as well as mass and shape of the projectile. For this reason, Fraunhofer EMI operates a large variety of launchers that address velocities up to ordnance velocities as single stage powder gun but which can also be operated as two-stage light gas guns achieving the regime of low earth orbital velocity. Thereby for projectile masses of up to 100 g hypervelocity impact phenomena up to 7.8 km/s can be addressed. Advanced optical diagnostic techniques like microsecond video are used as commercial systems but - since impact phenomena are mostly related with debris or dust - specialized diagnostics are developed in-house like x-ray cinematography and x-ray tomography. Selected topics of the field of applied impact physics will be presented like the interesting behavior of long rods penetrating low-density materials or experimental findings at hypervelocity for this class of materials as well as new x-ray diagnositic techniques.

Applications of flight control system methods to an advanced combat rotorcraft

NASA Technical Reports Server (NTRS)

Tischler, Mark B.; Fletcher, Jay W.; Morris, Patrick M.; Tucker, George T.

1989-01-01

Advanced flight control system design, analysis, and testing methodologies developed at the Ames Research Center are applied in an analytical and flight test evaluation of the Advanced Digital Optical Control System (ADOCS) demonstrator. The primary objectives are to describe the knowledge gained about the implications of digital flight control system design for rotorcraft, and to illustrate the analysis of the resulting handling-qualities in the context of the proposed new handling-qualities specification for rotorcraft. Topics covered in-depth are digital flight control design and analysis methods, flight testing techniques, ADOCS handling-qualities evaluation results, and correlation of flight test results with analytical models and the proposed handling-qualities specification. The evaluation of the ADOCS demonstrator indicates desirable response characteristics based on equivalent damping and frequency, but undersirably large effective time-delays (exceeding 240 m sec in all axes). Piloted handling-qualities are found to be desirable or adequate for all low, medium, and high pilot gain tasks; but handling-qualities are inadequate for ultra-high gain tasks such as slope and running landings.

Application of advanced diffraction based optical metrology overlay capabilities for high-volume manufacturing

NASA Astrophysics Data System (ADS)

Chen, Kai-Hsiung; Huang, Guo-Tsai; Hsieh, Hung-Chih; Ni, Wei-Feng; Chuang, S. M.; Chuang, T. K.; Ke, Chih-Ming; Huang, Jacky; Rao, Shiuan-An; Cumurcu Gysen, Aysegul; d'Alfonso, Maxime; Yueh, Jenny; Izikson, Pavel; Soco, Aileen; Wu, Jon; Nooitgedagt, Tjitte; Ottens, Jeroen; Kim, Yong Ho; Ebert, Martin

2017-03-01

On-product overlay requirements are becoming more challenging with every next technology node due to the continued decrease of the device dimensions and process tolerances. Therefore, current and future technology nodes require demanding metrology capabilities such as target designs that are robust towards process variations and high overlay measurement density (e.g. for higher order process corrections) to enable advanced process control solutions. The impact of advanced control solutions based on YieldStar overlay data is being presented in this paper. Multi patterning techniques are applied for critical layers and leading to additional overlay measurement demands. The use of 1D process steps results in the need of overlay measurements relative to more than one layer. Dealing with the increased number of overlay measurements while keeping the high measurement density and metrology accuracy at the same time presents a challenge for high volume manufacturing (HVM). These challenges are addressed by the capability to measure multi-layer targets with the recently introduced YieldStar metrology tool, YS350. On-product overlay results of such multi-layers and standard targets are presented including measurement stability performance.

Near real-time measurement of forces applied by an optical trap to a rigid cylindrical object

NASA Astrophysics Data System (ADS)

Glaser, Joseph; Hoeprich, David; Resnick, Andrew

2014-07-01

An automated data acquisition and processing system is established to measure the force applied by an optical trap to an object of unknown composition in real time. Optical traps have been in use for the past 40 years to manipulate microscopic particles, but the magnitude of applied force is often unknown and requires extensive instrument characterization. Measuring or calculating the force applied by an optical trap to nonspherical particles presents additional difficulties which are also overcome with our system. Extensive experiments and measurements using well-characterized objects were performed to verify the system performance.

Overview of microoptics: Past, present, and future

NASA Technical Reports Server (NTRS)

Veldkamp, Wilfrid B.

1993-01-01

Through advances in semiconductor miniaturization technology, microrelief patterns, with characteristic dimensions as small as the wavelength of light, can now be mass reproduced to form high-quality and low-cost optical components. In a unique example of technology transfer, from electronics to optics, this capability is allowing optics designers to create innovative optical components that promise to solve key problems in optical sensors, optical communication channels, and optical processors.

Optical interconnection and packaging technologies for advanced avionics systems

NASA Astrophysics Data System (ADS)

Schroeder, J. E.; Christian, N. L.; Cotti, B.

1992-09-01

An optical backplane developed to demonstrate the advantages of high-performance optical interconnections and supporting technologies and designed to be compatible with standard avionics racks is described. The hardware demonstrates the three basic components of optical interconnects: optical sources, an optical signal distribution network, and optical receivers. Results from characterization and environmental tests, including a demonstration of the reliable transmission of serial data at a 1 Gb/s, are reported.

Design of Optical Systems with Extended Depth of Field: An Educational Approach to Wavefront Coding Techniques

ERIC Educational Resources Information Center

Ferran, C.; Bosch, S.; Carnicer, A.

2012-01-01

A practical activity designed to introduce wavefront coding techniques as a method to extend the depth of field in optical systems is presented. The activity is suitable for advanced undergraduate students since it combines different topics in optical engineering such as optical system design, aberration theory, Fourier optics, and digital image…

REVIEWS OF TOPICAL PROBLEMS: Recent advances in X-ray refractive optics

NASA Astrophysics Data System (ADS)

Aristov, V. V.; Shabel'nikov, L. G.

2008-01-01

X-ray refractive optics has made rapid strides to a large degree due to the work of Russian scientists, and has now become one of the most rapidly advancing areas in modern physical optics. This review outlines the results of investigation of refractive devices and analysis of their properties. The conception of planar lenses made of silicon and other materials is set forth. We discuss the applications of refractive lenses to the transformation of X-ray images, photonic crystal research, and the development of focusing devices in high-energy X-ray telescopes.

Microscopic Imaging and Spectroscopy with Scattered Light

PubMed Central

Boustany, Nada N.; Boppart, Stephen A.; Backman, Vadim

2012-01-01

Optical contrast based on elastic scattering interactions between light and matter can be used to probe cellular structure and dynamics, and image tissue architecture. The quantitative nature and high sensitivity of light scattering signals to subtle alterations in tissue morphology, as well as the ability to visualize unstained tissue in vivo, has recently generated significant interest in optical scatter based biosensing and imaging. Here we review the fundamental methodologies used to acquire and interpret optical scatter data. We report on recent findings in this field and present current advances in optical scatter techniques and computational methods. Cellular and tissue data enabled by current advances in optical scatter spectroscopy and imaging stand to impact a variety of biomedical applications including clinical tissue diagnosis, in vivo imaging, drug discovery and basic cell biology. PMID:20617940

Eliminating crystals in non-oxide optical fiber preforms and optical fibers

NASA Technical Reports Server (NTRS)

LaPointe, Michael R. (Inventor); Tucker, Dennis S. (Inventor)

2010-01-01

A method is provided for eliminating crystals in non-oxide optical fiber preforms as well as optical fibers drawn therefrom. The optical-fiber-drawing axis of the preform is aligned with the force of gravity. A magnetic field is applied to the preform as it is heated to at least a melting temperature thereof. The magnetic field is applied in a direction that is parallel to the preform's optical-fiber-drawing axis. The preform is then cooled to a temperature that is less than a glass transition temperature of the preform while the preform is maintained in the magnetic field. When the processed preform is to have an optical fiber drawn therefrom, the preform's optical-fiber-drawing axis is again aligned with the force of gravity and a magnetic field is again applied along the axis as the optical fiber is drawn from the preform.

Converged photonic data storage and switch platform for exascale disaggregated data centers

NASA Astrophysics Data System (ADS)

Pitwon, R.; Wang, K.; Worrall, A.

2017-02-01

We report on a converged optically enabled Ethernet storage, switch and compute platform, which could support future disaggregated data center architectures. The platform includes optically enabled Ethernet switch controllers, an advanced electro-optical midplane and optically interchangeable generic end node devices. We demonstrate system level performance using optically enabled Ethernet disk drives and micro-servers across optical links of varied lengths.

US long distance fiber optic networks: Technology, evolution and advanced concepts. Volume 2: Fiber optic technology and long distance networks

NASA Astrophysics Data System (ADS)

1986-10-01

The study projects until 2000 the evolution of long distance fiber optic networks in the U.S. Volume 1 is the Executive Summary. Volume 2 focuses on fiber optic components and systems that are directly related to the operation of long-haul networks. Optimistic, pessimistic and most likely scenarios of technology development are presented. The activities of national and regional companies implementing fiber long haul networks are also highlighted, along with an analysis of the market and regulatory forces affecting network evolution. Volume 3 presents advanced fiber optic network concept definitions. Inter-LATA traffic is quantified and forms the basis for the construction of 11-, 15-, 17-, and 23-node networks. Using the technology projections from Volume 2, a financial model identifies cost drivers and determines circuit mile costs between any two LATAs. A comparison of fiber optics with alternative transmission concludes the report.

Recent flight-test results of optical airdata techniques

NASA Technical Reports Server (NTRS)

Bogue, Rodney K.

1993-01-01

Optical techniques for measuring airdata parameters were demonstrated with promising results on high performance fighter aircraft. These systems can measure the airspeed vector, and some are not as dependent on special in-flight calibration processes as current systems. Optical concepts for measuring freestream static temperature and density are feasible for in-flight applications. The best feature of these concepts is that the air data measurements are obtained nonintrusively, and for the most part well into the freestream region of the flow field about the aircraft. Current requirements for measuring air data at high angle of attack, and future need to measure the same information at hypersonic flight conditions place strains on existing techniques. Optical technology advances show outstanding potential for application in future programs and promise to make common use of optical concepts a reality. Results from several flight-test programs are summarized, and the technology advances required to make optical airdata techniques practical are identified.

US long distance fiber optic networks: Technology, evolution and advanced concepts. Volume 2: Fiber optic technology and long distance networks

NASA Technical Reports Server (NTRS)

1986-01-01

The study projects until 2000 the evolution of long distance fiber optic networks in the U.S. Volume 1 is the Executive Summary. Volume 2 focuses on fiber optic components and systems that are directly related to the operation of long-haul networks. Optimistic, pessimistic and most likely scenarios of technology development are presented. The activities of national and regional companies implementing fiber long haul networks are also highlighted, along with an analysis of the market and regulatory forces affecting network evolution. Volume 3 presents advanced fiber optic network concept definitions. Inter-LATA traffic is quantified and forms the basis for the construction of 11-, 15-, 17-, and 23-node networks. Using the technology projections from Volume 2, a financial model identifies cost drivers and determines circuit mile costs between any two LATAs. A comparison of fiber optics with alternative transmission concludes the report.

Acousto-Optic Tunable Filter for Time-Domain Processing of Ultra-Short Optical Pulses,

DTIC Science & Technology

The application of acousto - optic tunable filters for shaping of ultra-fast pulses in the time domain is analyzed and demonstrated. With the rapid...advance of acousto - optic tunable filter (AOTF) technology, the opportunity for sophisticated signal processing capabilities arises. AOTFs offer unique

Ultralightweight optics for space applications

NASA Astrophysics Data System (ADS)

Mayo, James W.; DeHainaut, Linda L.; Bell, Kevin D.; Smith, Winfred S.; Killpatrick, Don H.; Dyer, Richard W.

2000-07-01

Lightweight, deployable space optics has been identified as a key technology for future cost-effective, space-based systems. The United States Department of Defense has partnered with the National Aeronautical Space Administration to implement a space mirror technology development activity known as the Advanced Mirror System Demonstrator (AMSD). The AMSD objectives are to advance technology in the production of low-mass primary mirror systems, reduce mirror system cost and shorten mirror- manufacturing time. The AMSD program will offer substantial weight, cost and production rate improvements over Hubble Space Telescope mirror technology. A brief history of optical component development and a review of optical component state-of-the-art technology will be given, and the AMSD program will be reviewed.

Advanced optical imaging platform for CD metrology and defect review on 130-nm to 100-nm node reticles: an overview of preliminary results

NASA Astrophysics Data System (ADS)

Hourd, Andrew C.; Grimshaw, Anthony; Scheuring, Gerd; Gittinger, Christian; Brueck, Hans-Juergen; Chen, Shiuh-Bin; Chen, Parkson W.; Hartmann, Hans; Ordynskyy, Volodymyr; Jonckheere, Rik M.; Philipsen, Vicky; Schaetz, Thomas; Sommer, Karl

2002-08-01

Critical Dimension fidelity continues to be one of the key driving parameters defining photomask quality and printing performance. The present advanced optical CD metrology systems, operating at i-line, will very soon be challenged as viable tools owing to their restricted resolution and measurement linearity impact on the ability to produce repeatable measurements. Alternative measurement technologies such as CD-SEM and -AFM have started to appear, but are also not without tier concerns in the field of reticle CD metrology. This paper introduces a new optical metrology system (MueTec /) operating at DUV wavelength (248nm), which has been specifically designed to meet the resolution and measurement repeatability requirements of reticle manufacture at the 130nm and 100nm nodes. The system is based upon a specially designed mechanical-optical platform for maximum stability and very advanced optical, illumination, alignment and software systems. The at wavelength operation of this system also makes it an ideal platform for defect printability analysis and review. The system is currently part of a European Commission funded assessment project (IST-2000-28086: McD'OR) to develop a testing strategy to verify the system performance, agree on equipment specifications and demonstrate its capability on advanced production reticles - including long-term reliability. It is the preliminary results from this evaluation that are presented here.

Optical design considerations for high-concentration photovoltaics

NASA Astrophysics Data System (ADS)

Garboushian, Vahan; Gordon, Robert

2006-08-01

Over the past 15 years, major advances in Concentrating Photovoltaics (CPV) have been achieved. Ultra-efficient Si solar cells have produced commercial concentration systems which are being fielded today and are competitively priced. Advanced research has primarily focused on significantly more efficient multi-junction solar cells for tomorrow's systems. This effort has produced sophisticated solar cells that significantly improve power production. Additional performance and cost improvements, especially in the optical system area and system integration, must be made before CPV can realize its ultimate commercial potential. Structural integrity and reliability are vital for commercial success. As incremental technical improvements are made in solar cell technologies, evaluation and 'fine-tuning' of optical systems properly matched to the solar cell are becoming increasingly necessary. As we move forward, it is increasingly important to optimize all of the interrelated elements of a CPV system for high performance without sacrificing the marketable cost and structural requirements of the system. Areas such as wavelength absorption of refractive optics need to be carefully matched to the solar cell technology employed. Reflective optics require advanced engineering models to insure uniform flux distribution without excessive losses. In Situ measurement of the 'fine-grain' improvements are difficult as multiple variables such as solar insolation, temperature, wind, altitude, etc. infringe on analytical data. This paper discusses design considerations based on 10 years of field trials of high concentration systems and their relevance for tomorrow's advanced CPV systems.

The Application of Leap Motion in Astronaut Virtual Training

NASA Astrophysics Data System (ADS)

Qingchao, Xie; Jiangang, Chao

2017-03-01

With the development of computer vision, virtual reality has been applied in astronaut virtual training. As an advanced optic equipment to track hand, Leap Motion can provide precise and fluid tracking of hands. Leap Motion is suitable to be used as gesture input device in astronaut virtual training. This paper built an astronaut virtual training based Leap Motion, and established the mathematics model of hands occlusion. At last the ability of Leap Motion to handle occlusion was analysed. A virtual assembly simulation platform was developed for astronaut training, and occlusion gesture would influence the recognition process. The experimental result can guide astronaut virtual training.

Absorbance Based Light Emitting Diode Optical Sensors and Sensing Devices

PubMed Central

O'Toole, Martina; Diamond, Dermot

2008-01-01

The ever increasing demand for in situ monitoring of health, environment and security has created a need for reliable, miniaturised sensing devices. To achieve this, appropriate analytical devices are required that possess operating characteristics of reliability, low power consumption, low cost, autonomous operation capability and compatibility with wireless communications systems. The use of light emitting diodes (LEDs) as light sources is one strategy, which has been successfully applied in chemical sensing. This paper summarises the development and advancement of LED based chemical sensors and sensing devices in terms of their configuration and application, with the focus on transmittance and reflectance absorptiometric measurements. PMID:27879829

Absorbance Based Light Emitting Diode Optical Sensors and Sensing Devices.

PubMed

O'Toole, Martina; Diamond, Dermot

2008-04-07

The ever increasing demand for in situ monitoring of health, environment and security has created a need for reliable, miniaturised sensing devices. To achieve this, appropriate analytical devices are required that possess operating characteristics of reliability, low power consumption, low cost, autonomous operation capability and compatibility with wireless communications systems. The use of light emitting diodes (LEDs) as light sources is one strategy, which has been successfully applied in chemical sensing. This paper summarises the development and advancement of LED based chemical sensors and sensing devices in terms of their configuration and application, with the focus on transmittance and reflectance absorptiometric measurements.

Single-point diamond crushing of Zerodur with in-situ polishing and metrology on a diamond turning machine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bryan, J.B.; Carter, D.L.

1985-04-01

Large, complicated, aspherical optical elements of glass are presently used in many astronomical devices, both on land and in space. Grazing-incident mirrors are envisioned for use in such missions as the proposed Advanced X-Ray Astrophysical Facility (AXAF), the Far Ultraviolet Spectroscopic Explorer (FUSE), and others. These elements are very expensive to fabricate because a great deal of time and labor are required to shape a glass blank. The fabrication of these mirrors can best be achieved by applying precision machining techniques and precision machines for figuring and finishing low-expansion glasses such as Zerodur.

Research studies on advanced optical module/head designs for optical devices

NASA Technical Reports Server (NTRS)

Burke, James J.

1991-01-01

A summary is presented of research in optical data storage materials and of research at the center. The first section contains summary reports under the general headings of: (1) Magnetooptic media: modeling, design, fabrication, characterization, and testing; (2) Optical heads: holographic optical elements; and (3) Optical heads: integrated optics. The second section consist of a proposal entitled, Signal Processing Techniques for Optical Data Storage. And section three presents various publications prepared by the center.

High pressure fiber optic sensor system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Guida, Renato; Xia, Hua; Lee, Boon K

2013-11-26

The present application provides a fiber optic sensor system. The fiber optic sensor system may include a small diameter bellows, a large diameter bellows, and a fiber optic pressure sensor attached to the small diameter bellows. Contraction of the large diameter bellows under an applied pressure may cause the small diameter bellows to expand such that the fiber optic pressure sensor may measure the applied pressure.

Velocity filtering applied to optical flow calculations

NASA Technical Reports Server (NTRS)

Barniv, Yair

1990-01-01

Optical flow is a method by which a stream of two-dimensional images obtained from a forward-looking passive sensor is used to map the three-dimensional volume in front of a moving vehicle. Passive ranging via optical flow is applied here to the helicopter obstacle-avoidance problem. Velocity filtering is used as a field-based method to determine range to all pixels in the initial image. The theoretical understanding and performance analysis of velocity filtering as applied to optical flow is expanded and experimental results are presented.

MULTI-CORE AND OPTICAL PROCESSOR RELATED APPLICATIONS RESEARCH AT OAK RIDGE NATIONAL LABORATORY

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barhen, Jacob; Kerekes, Ryan A; ST Charles, Jesse Lee

2008-01-01

High-speed parallelization of common tasks holds great promise as a low-risk approach to achieving the significant increases in signal processing and computational performance required for next generation innovations in reconfigurable radio systems. Researchers at the Oak Ridge National Laboratory have been working on exploiting the parallelization offered by this emerging technology and applying it to a variety of problems. This paper will highlight recent experience with four different parallel processors applied to signal processing tasks that are directly relevant to signal processing required for SDR/CR waveforms. The first is the EnLight Optical Core Processor applied to matched filter (MF) correlationmore » processing via fast Fourier transform (FFT) of broadband Dopplersensitive waveforms (DSW) using active sonar arrays for target tracking. The second is the IBM CELL Broadband Engine applied to 2-D discrete Fourier transform (DFT) kernel for image processing and frequency domain processing. And the third is the NVIDIA graphical processor applied to document feature clustering. EnLight Optical Core Processor. Optical processing is inherently capable of high-parallelism that can be translated to very high performance, low power dissipation computing. The EnLight 256 is a small form factor signal processing chip (5x5 cm2) with a digital optical core that is being developed by an Israeli startup company. As part of its evaluation of foreign technology, ORNL's Center for Engineering Science Advanced Research (CESAR) had access to a precursor EnLight 64 Alpha hardware for a preliminary assessment of capabilities in terms of large Fourier transforms for matched filter banks and on applications related to Doppler-sensitive waveforms. This processor is optimized for array operations, which it performs in fixed-point arithmetic at the rate of 16 TeraOPS at 8-bit precision. This is approximately 1000 times faster than the fastest DSP available today. The optical core performs the matrix-vector multiplications, where the nominal matrix size is 256x256. The system clock is 125MHz. At each clock cycle, 128K multiply-and-add operations per second (OPS) are carried out, which yields a peak performance of 16 TeraOPS. IBM Cell Broadband Engine. The Cell processor is the extraordinary resulting product of 5 years of sustained, intensive R&D collaboration (involving over $400M investment) between IBM, Sony, and Toshiba. Its architecture comprises one multithreaded 64-bit PowerPC processor element (PPE) with VMX capabilities and two levels of globally coherent cache, and 8 synergistic processor elements (SPEs). Each SPE consists of a processor (SPU) designed for streaming workloads, local memory, and a globally coherent direct memory access (DMA) engine. Computations are performed in 128-bit wide single instruction multiple data streams (SIMD). An integrated high-bandwidth element interconnect bus (EIB) connects the nine processors and their ports to external memory and to system I/O. The Applied Software Engineering Research (ASER) Group at the ORNL is applying the Cell to a variety of text and image analysis applications. Research on Cell-equipped PlayStation3 (PS3) consoles has led to the development of a correlation-based image recognition engine that enables a single PS3 to process images at more than 10X the speed of state-of-the-art single-core processors. NVIDIA Graphics Processing Units. The ASER group is also employing the latest NVIDIA graphical processing units (GPUs) to accelerate clustering of thousands of text documents using recently developed clustering algorithms such as document flocking and affinity propagation.« less

Advancing the state-of-the-art of the optical atomic clock

NASA Astrophysics Data System (ADS)

Ye, Jun

2014-05-01

The continued advance in laser phase coherence has permitted an improvement of the stability of optical lattice clocks by a factor of 10. This measurement precision has facilitated characterization of systematic effects, allowing us to improve the lattice clock accuracy by a factor of 20. The accuracy and stability of the JILA Sr clock now reach the 10-18 level. Owing to these advances, the lattice clock has also emerged as an effective laboratory to study many-body spin correlations. NIST, NSF, DARPA-QuASAR.

Advanced Propulsion Physics Lab: Eagleworks Investigations

NASA Technical Reports Server (NTRS)

Scogin, Tyler

2014-01-01

Eagleworks Laboratory is an advanced propulsions physics laboratory with two primary investigations currently underway. The first is a Quantum Vacuum Plasma Thruster (QVPT or Q-thrusters), an advanced electric propulsion technology in the development and demonstration phase. The second investigation is in Warp Field Interferometry (WFI). This is an investigation of Dr. Harold "Sonny" White's theoretical physics models for warp field equations using optical experiments in the Electro Optical laboratory (EOL) at Johnson Space Center. These investigations are pursuing technology necessary to enable human exploration of the solar system and beyond.

Optical-domain subsampling for data efficient depth ranging in Fourier-domain optical coherence tomography

PubMed Central

Siddiqui, Meena; Vakoc, Benjamin J.

2012-01-01

Recent advances in optical coherence tomography (OCT) have led to higher-speed sources that support imaging over longer depth ranges. Limitations in the bandwidth of state-of-the-art acquisition electronics, however, prevent adoption of these advances into the clinical applications. Here, we introduce optical-domain subsampling as a method for imaging at high-speeds and over extended depth ranges but with a lower acquisition bandwidth than that required using conventional approaches. Optically subsampled laser sources utilize a discrete set of wavelengths to alias fringe signals along an extended depth range into a bandwidth limited frequency window. By detecting the complex fringe signals and under the assumption of a depth-constrained signal, optical-domain subsampling enables recovery of the depth-resolved scattering signal without overlapping artifacts from this bandwidth-limited window. We highlight key principles behind optical-domain subsampled imaging, and demonstrate this principle experimentally using a polygon-filter based swept-source laser that includes an intra-cavity Fabry-Perot (FP) etalon. PMID:23038343

Advanced optical systems for ultra high energy cosmic rays detection

NASA Astrophysics Data System (ADS)

Gambicorti, L.; Pace, E.; Mazzinghi, P.

2017-11-01

A new advanced optical system is proposed and analysed in this work with the purpose to improve the photons collection efficiency of Multi-AnodePhotoMultipliers (MAPMT) detectors, which will be used to cover large focal surface of instruments dedicated to the Ultra High Energy Cosmic Rays (UHECRs, above 1019eV) and Ultra High Energy Neutrino (UHEN) detection. The employment of the advanced optical system allows to focus all photons inside the sensitive area of detectors and to improve the signal-to-noise ratios in the wavelength range of interest (300-400nm), thus coupling imaging and filtering capability. Filter is realised with a multilayer coating to reach high transparency in UV range and with a sharp cut-off outside. In this work the applications on different series of PMTs have been studied and results of simulations are shown. First prototypes have been realised. Finally, this paper proposes another class of adapters to be optically coupled on each pixel of MAPMT detector selected, consisting of non-imaging concentrators as Winston cones.

Advancements in non-contact metrology of asphere and diffractive optics

NASA Astrophysics Data System (ADS)

DeFisher, Scott

2017-11-01

Advancements in optical manufacturing technology allow optical designers to implement steep aspheric or high departure surfaces into their systems. Measuring these surfaces with profilometers or CMMs can be difficult due to large surface slopes or sharp steps in the surface. OptiPro has developed UltraSurf to qualify the form and figure of steep aspheric and diffractive optics. UltraSurf is a computer controlled, non-contact coordinate measuring machine. It incorporates five air-bearing axes, linear motors, high-resolution feedback, and a non-contact probe. The measuring probe is scanned over the optical surface while maintaining perpendicularity and a constant focal offset. Multiple probe technologies are available on UltraSurf. Each probe has strengths and weaknesses relative to the material properties, surface finish, and figure error of an optical component. The measuring probes utilize absolute distance to resolve step heights and diffractive surface patterns. The non-contact scanning method avoids common pitfalls with stylus contact instruments. Advancements in measuring speed and precision has enabled fast and accurate non-contact metrology of diffractive and steep aspheric surfaces. The benefits of data sampling with twodimensional profiles and three-dimensional topography maps will be presented. In addition, accuracy, repeatability, and machine qualification will be discussed with regards to aspheres and diffractive surfaces.

An advanced optical system for laser ablation propulsion in space

NASA Astrophysics Data System (ADS)

Bergstue, Grant; Fork, Richard; Reardon, Patrick

2014-03-01

We propose a novel space-based ablation driven propulsion engine concept utilizing transmitted energy in the form of a series of ultra-short optical pulses. Key differences are generating the pulses at the transmitting spacecraft and the safe delivery of that energy to the receiving spacecraft for propulsion. By expanding the beam diameter during transmission in space, the energy can propagate at relatively low intensity and then be refocused and redistributed to create an array of ablation sites at the receiver. The ablation array strategy allows greater control over flight dynamics and eases thermal management. Research efforts for this transmission and reception of ultra-short optical pulses include: (1) optical system design; (2) electrical system requirements; (3) thermal management; (4) structured energy transmission safety. Research has also been focused on developing an optical switch concept for the multiplexing of the ultra-short pulses. This optical switch strategy implements multiple reflectors polished into a rotating momentum wheel device to combine the pulses from different laser sources. The optical system design must minimize the thermal load on any one optical element. Initial specifications and modeling for the optical system are being produced using geometrical ray-tracing software to give a better understanding of the optical requirements. In regards to safety, we have advanced the retro-reflective beam locking strategy to include look-ahead capabilities for long propagation distances. Additional applications and missions utilizing multiplexed pulse transmission are also presented. Because the research is in early development, it provides an opportunity for new and valuable advances in the area of transmitted energy for propulsion as well as encourages joint international efforts. Researchers from different countries can cooperate in order to find constructive and safe uses of ordered pulse transmission for propulsion in future space-based missions.

Near infrared spectroscopy of human muscles

NASA Astrophysics Data System (ADS)

Gasbarrone, R.; Currà, A.; Cardillo, A.; Bonifazi, G.; Serranti, S.

2018-02-01

Optical spectroscopy is a powerful tool in research and industrial applications. Its properties of being rapid, non-invasive and not destructive make it a promising technique for qualitative as well as quantitative analysis in medicine. Recent advances in materials and fabrication techniques provided portable, performant, sensing spectrometers readily operated by user-friendly cabled or wireless systems. We used such a system to test whether infrared spectroscopy techniques, currently utilized in many areas as primary/secondary raw materials sector, cultural heritage, agricultural/food industry, environmental remote and proximal sensing, pharmaceutical industry, etc., could be applied in living humans to categorize muscles. We acquired muscles infrared spectra in the Vis-SWIR regions (350-2500 nm), utilizing an ASD FieldSpec 4 Standard-Res Spectroradiometer with a spectral sampling capability of 1.4 nm at 350-1000 nm and 1.1 nm at 1001-2500 nm. After a preliminary spectra pre-processing (i.e. signal scattering reduction), Principal Component Analysis (PCA) was applied to identify similar spectral features presence and to realize their further grouping. Partial Least-Squares Discriminant Analysis (PLS-DA) was utilized to implement discrimination/prediction models. We studied 22 healthy subjects (age 25-89 years, 11 females), by acquiring Vis-SWIR spectra from the upper limb muscles (i.e. biceps, a forearm flexor, and triceps, a forearm extensor). Spectroscopy was performed in fixed limb postures (elbow angle approximately 90‡). We found that optical spectroscopy can be applied to study human tissues in vivo. Vis-SWIR spectra acquired from the arm detect muscles, distinguish flexors from extensors.

Imaging and applied optics: introduction to the feature issue.

PubMed

Zalevsky, Zeev; Arnison, Matthew R; Javidi, Bahram; Testorf, Markus

2018-03-01

This special issue of Applied Optics contains selected papers from OSA's Imaging Congress with particular emphasis on work from mathematics in imaging, computational optical sensing and imaging, imaging systems and applications, and 3D image acquisition and display.

Integrated optical circuit engineering V; Proceedings of the Meeting, San Diego, CA, Aug. 17-20, 1987

NASA Astrophysics Data System (ADS)

Mentzer, Mark A.

Recent advances in the theoretical and practical design and applications of optoelectronic devices and optical circuits are examined in reviews and reports. Topics discussed include system and market considerations, guided-wave phenomena, waveguide devices, processing technology, lithium niobate devices, and coupling problems. Consideration is given to testing and measurement, integrated optics for fiber-optic systems, optical interconnect technology, and optical computing.

Distributed abnormalities of brain white matter architecture in patients with dominant optic atrophy and OPA1 mutations.

PubMed

Rocca, Maria A; Bianchi-Marzoli, Stefania; Messina, Roberta; Cascavilla, Maria Lucia; Zeviani, Massimo; Lamperti, Costanza; Milesi, Jacopo; Carta, Arturo; Cammarata, Gabriella; Leocani, Letizia; Lamantea, Eleonora; Bandello, Francesco; Comi, Giancarlo; Falini, Andrea; Filippi, Massimo

2015-05-01

Using advanced MRI techniques, we investigated the presence and topographical distribution of brain grey matter (GM) and white matter (WM) alterations in dominant optic atrophy (DOA) patients with genetically proven OPA1 mutation as well as their correlation with clinical and neuro-ophthalmologic findings. Nineteen DOA patients underwent neurological, neuro-ophthalmologic and brainstem auditory evoked potentials (BAEP) evaluations. Voxel-wise methods were applied to assess regional GM and WM abnormalities in patients compared to 20 healthy controls. Visual acuity was reduced in 16 patients. Six DOA patients (4 with missense mutations) had an abnormal I peripheral component (auditory nerve) at BAEP. Compared to controls, DOA patients had significant atrophy of the optic nerves (p < 0.0001). Voxel-based morphometry (VBM) analysis showed that, compared to controls, DOA patients had significant WM atrophy of the chiasm and optic tracts; whereas no areas of GM atrophy were found. Tract-based spatial statistics (TBSS) analysis showed that compared to controls, DOA patients had significantly lower mean diffusivity, axial and radial diffusivity in the WM of the cerebellum, brainstem, thalamus, fronto-occipital-temporal lobes, including the cingulum, corpus callosum, corticospinal tract and optic radiation bilaterally. No abnormalities of fractional anisotropy were detected. No correlations were found between volumetric and diffusivity abnormalities quantified with MRI and clinical and neuro-ophthalmologic measures of disease severity. Consistently with pathological studies, tissue loss in DOA patients is limited to anterior optic pathways reflecting retinal ganglion cell degeneration. Distributed abnormalities of diffusivity indexes might reflect abnormal intracellular mitochondrial morphology as well as alteration of protein levels due to OPA1 mutations.

Advanced polarization sensitive analysis in optical coherence tomography

NASA Astrophysics Data System (ADS)

Wieloszyńska, Aleksandra; StrÄ kowski, Marcin R.

2017-08-01

The optical coherence tomography (OCT) is an optical imaging method, which is widely applied in variety applications. This technology is used to cross-sectional or surface imaging with high resolution in non-contact and non-destructive way. OCT is very useful in medical applications like ophthalmology, dermatology or dentistry, as well as beyond biomedical fields like stress mapping in polymers or protective coatings defects detection. Standard OCT imaging is based on intensity images which can visualize the inner structure of scattering devices. However, there is a number of extensions improving the OCT measurement abilities. The main of them are the polarization sensitive OCT (PS-OCT), Doppler enable OCT (D-OCT) or spectroscopic OCT (S-OCT). Our research activities have been focused on PS-OCT systems. The polarization sensitive analysis delivers an useful information about optical anisotropic properties of the evaluated sample. This kind of measurements is very important for inner stress monitoring or e.g. tissue recognition. Based on our research results and knowledge the standard PS-OCT provide only data about birefringence of the measured sample. However, based on the OCT measurements more information including depolarization and diattenuation might be obtained. In our work, the method based on Jones formalism are going to be presented. It is used to determine birefringence, dichroism and optic axis orientation of the tested sample. In this contribution the setup of the optical system, as well as tests results verifying the measurements abilities of the system are going to be presented. The brief discussion about the effectiveness and usefulness of this approach will be carried out.

Mathematical Modeling of Optical Radiation Emission as a Function of Welding Power during Gas Shielded Metal Arc Welding.

PubMed

Bauer, Stefan; Janßen, Marco; Schmitz, Martin; Ott, Günter

2017-11-01

Arc welding is accompanied by intense optical radiation emission that can be detrimental not only for the welder himself but also for people working nearby or for passersby. Technological progress advances continuously in the field of joining, so an up-to-date radiation database is necessary. Additionally, many literature irradiance data have been measured for a few welding currents or for parts of the optical spectral region only. Within this paper, a comprehensive study of contemporary metal active gas, metal inert gas, and cold metal transfer welding is presented covering optical radiation emission from 200 up to 2,700 nm by means of (spectro-) radiometric measurements. The investigated welding currents range from 70 to 350 A, reflecting values usually applied in industry. Based upon these new irradiance data, three mathematical models were derived in order to describe optical radiation emission as a function of welding power. The linear, exponential, and sigmoidal emission models depend on the process variant (standard or pulsed) as well as on the welding material (mild and stainless steel, aluminum). In conjunction with the corresponding exposure limit values for incoherent optical radiation maximum permissible exposure durations were calculated as a function of welding power. Typical times are shorter than 1 s for the ultraviolet spectral region and range from 1 to 10 s for visible radiation. For the infrared regime, exposure durations are of the order of minutes to hours. Finally, a validation of the metal active gas emission models was carried out with manual arc welding.

Fly-by-Light Advanced Systems Hardware (FLASH) program

NASA Astrophysics Data System (ADS)

Bedoya, Carlos A.

1995-05-01

Fiber optics are immune to electromagnetic emissions and have the potential to eliminate this concern especially in flight critical applications if they can be developed to the same level of technology as current systems using wire to carry the signals. As aircraft become more and more dependent of digital signals to control all systems, the Electromagnetic Environment (EME) will become more and more a concern for the safe long term operation. The International Severe HIRF electromagnetic environment (EME) is less than 2000 Volts per meter below 400 MHz and reaches a maximum of 6,850 Volts per meter in the 4-6 GHz range. The normal assumption is that a metal or composite aircraft skin with appropriate seals provides 20 dB attenuation of the external environment. This reduces peak levels at the avionics boxes to less than 200 Volts per meter below 400 MHz and a maximum of 685 Volts per meter in the 406 GHz range. MIL-STD-461D imposed an additional box level requirement to 200 Volts per meter from 10 KHz to 40 GHz. This requirement equals or surpasses the attenuated HIRF environment over significant portions of the spectrum and implies that the aircraft must be designed to achieve and maintain this value throughout its service life. Although wires can be shielded and designed to achieve these requirements, it is a more expensive process, adds the weight of shielding and requires maintenance of the shielding integrity at all times. The very light weight and high bandwidth of fiber optics also offer the potential of eliminating the number of connections and weight savings in aircraft. For example on a one to one replacement of wire by fiber, it is estimated that fiber would weight about 1/20 the weight of wire. Current wire buses used for duplex communications in aircraft applications have a bandwidth of about 1 MHz while equivalent buses using fiber optics have a bandwidth of 20 MHz. For other applications such as video and avionics interfaces, fiber buses in the hundreds of MHz are available. Applications of fiber optic buses would then result in the reduction of wires and connections because of reduction in the number of buses needed for information transfer due to the fact that a large number of different signals can be sent across one fiber by multiplexing each signal. The Advanced Research Projects Agency (ARPA) Technology Reinvestment Project (TRP) Fly-by-Light Advanced Systems Hardware (FLASH) program addresses the development of Fly-by-Light Technology in order to apply the benefits of fiber optics to military and commercial aircraft.

Possibilities in optical monitoring of laser welding process

NASA Astrophysics Data System (ADS)

Horník, Petr; Mrňa, Libor; Pavelka, Jan

2016-11-01

Laser welding is a modern, widely used but still not really common method of welding. With increasing demands on the quality of the welds, it is usual to apply automated machine welding and with on-line monitoring of the welding process. The resulting quality of the weld is largely affected by the behavior of keyhole. However, its direct observation during the welding process is practically impossible and it is necessary to use indirect methods. At ISI we have developed optical methods of monitoring the process. Most advanced is an analysis of radiation of laser-induced plasma plume forming in the keyhole where changes in the frequency of the plasma bursts are monitored and evaluated using Fourier and autocorrelation analysis. Another solution, robust and suitable for industry, is based on the observation of the keyhole inlet opening through a coaxial camera mounted in the welding head and the subsequent image processing by computer vision methods. A high-speed camera is used to understand the dynamics of the plasma plume. Through optical spectroscopy of the plume, we can study the excitation of elements in a material. It is also beneficial to monitor the gas flow of shielding gas using schlieren method.

Development of a second generation SiLC-based Laue lens

NASA Astrophysics Data System (ADS)

Girou, David; Wade, Colin; Barrière, Nicolas; Collon, Maximilien; Günther, Ramses; Hanlon, Lorraine; Tomsick, John; Uliyanov, Alexey; Vacanti, Giuseppe; Zoglauer, Andreas

2017-09-01

For more than a decade, cosine has been developing silicon pore optics (SPO), lightweight modular X-ray optics made of stacks of bent and directly bonded silicon mirror plates. This technology, which has been selected by ESA to realize the optics of ATHENA, can also be used to fabricate soft gamma-ray Laue lenses where Bragg diffraction through the bulk silicon is exploited, rather than grazing incidence reflection. Silicon Laue Components (SiLCs) are made of stacks of curved, polished, wedged silicon plates, allowing the concentration of radiation in both radial and azimuthal directions. This greatly increases the focusing properties of a Laue lens since the size of the focal spot is no longer determined by the size of the individual single crystals, but by the accuracy of the applied curvature. After a successful proof of concept in 2013, establishing the huge potential of this technology, a new project has been launched in Spring 2017 at cosine to further develop and test this technique. Here we present the latest advances of the second generation of SiLCs made from even thinner silicon plates stacked by a robot with dedicated tools in a class-100 clean room environment.

The FOXSI solar sounding rocket campaigns

NASA Astrophysics Data System (ADS)

Glesener, Lindsay; Krucker, Säm.; Christe, Steven; Ishikawa, Shin-nosuke; Buitrago-Casas, Juan Camilo; Ramsey, Brian; Gubarev, Mikhail; Takahashi, Tadayuki; Watanabe, Shin; Takeda, Shin'ichiro; Courtade, Sasha; Turin, Paul; McBride, Stephen; Shourt, Van; Hoberman, Jane; Foster, Natalie; Vievering, Juliana

2016-07-01

The Focusing Optics X-ray Solar Imager (FOXSI) is, in its initial form, a sounding rocket experiment designed to apply the technique of focusing hard X-ray (HXR) optics to the study of fundamental questions about the high-energy Sun. Solar HXRs arise via bremsstrahlung from energetic electrons and hot plasma produced in solar flares and thus are one of the most direct diagnostics of are-accelerated electrons and the impulsive heating of the solar corona. Previous missions have always been limited in sensitivity and dynamic range by the use of indirect (Fourier) imaging due to the lack of availability of direct focusing optics, but technological advances now make direct focusing accessible in the HXR regime (as evidenced by the NuSTAR spacecraft and several suborbital missions). The FOXSI rocket experiment develops and optimizes HXR focusing telescopes for the unique scientific requirements of the Sun. To date, FOXSI has completed two successful flights on 2012 November 02 and 2014 December 11 and is funded for a third flight. This paper gives a brief overview of the experiment, which is sensitive to solar HXRs in the 4-20 keV range, describes its first two flights, and gives a preview of plans for FOXSI-3.

Raman spectroscopic instrumentation and plasmonic methods for material characterization

NASA Astrophysics Data System (ADS)

Tanaka, Kazuki

The advent of nanotechnology has led to incredible growth in how we consume, make and approach advanced materials. By exploiting nanoscale material properties, unique control of optical, thermal, mechanical, and electrical characteristics becomes possible. This thesis describes the development of a novel localized surface plasmon resonant (LSPR) color sensitive photosensor, based on functionalization of gold nanoparticles onto tianium dioxide nanowires and sensing by a metal-semiconducting nanowire-metal photodiode structure. This LSPR photosensor has been integrated into a system that incorporates Raman spectroscopy, microfluidics, optical trapping, and sorting flow cytometry into a unique material characterization system called the microfluidic optical fiber trapping Raman sorting flow cytometer (MOFTRSFC). Raman spectroscopy is utilized as a powerful molecular characterization technique used to analyze biological, mineralogical and nanomaterial samples. To combat the inherently weak Raman signal, plasmonic methods have been applied to exploit surface enhanced Raman scattering (SERS) and localized surface plasmon resonance (LSPR), increasing Raman intensity by up to 5 orders of magnitude. The resultant MOFTRSFC system is a prototype instrument that can effectively trap, analyze, and sort micron-sized dielectric particles and biological cells. Raman spectroscopy has been presented in several modalities, including the development of a portable near-infrared Raman spectrometer and other emerging technologies.

Vortex based information storage in Bose-Einstein condensates

NASA Astrophysics Data System (ADS)

Dutton, Zachary; Ruostekoski, Janne

2004-05-01

Recent demonstrations of coherent optical storage in atomic clouds [1,2] have opened up new possibilities for both classical and quantum information storage. In parallel, there have been advances in the generation of Laguerre-Gaussian (LG) modes with angular momentum (optical vortices)[3] and applications of these modes to quantum information architectures based on a alphabets larger than the traditional two-state systems. Here we theoretically consider the storage of such LG modes in atomic Rb-87 Bose-Einstein condensates (BECs). An LG mode writes its vortex phase pattern into a two-component BEC vortex state. The angular momentum information can then be stored in the BEC and then efficiently read back onto the optical field by switching a control field on. We study the fidelity of the writing, storage, and read-out processes. We also consider applying this method to to the transfer of more complicated states, such as two-component vortex lattices, between two spatially distinct BECs. 1. C. Liu, Z. Dutton, C.H. Behroozi, and L.V. Hau, Nature 409, 490 (2001). 2. D.F. Phillips, A. Fleischhauer, A. Mair, R.L. Walsworth, and M.D. Lukin, Phys. Rev. Lett. 86, 783 (2001). 3. A. Vaziri, Gregor Weihs, and A. Zeilinger, cond-mat/0111033.

The FOXSI Solar Sounding Rocket Campaigns

NASA Technical Reports Server (NTRS)

Glesener, Lindsay; Krucker, Sam; Christe, Steven; Ishikawa, Shin-Nosuke; Buitrago-Casas, Juan Camilo; Ramsey, Brian; Gubarev, Mikhail; Takahashi, Tadayuki; Watanabe, Shin; Takeda, Shin'ichiro;

Deep brain optical measurements of cell type-specific neural activity in behaving mice.

PubMed

Cui, Guohong; Jun, Sang Beom; Jin, Xin; Luo, Guoxiang; Pham, Michael D; Lovinger, David M; Vogel, Steven S; Costa, Rui M

2014-01-01

Recent advances in genetically encoded fluorescent sensors enable the monitoring of cellular events from genetically defined groups of neurons in vivo. In this protocol, we describe how to use a time-correlated single-photon counting (TCSPC)-based fiber optics system to measure the intensity, emission spectra and lifetime of fluorescent biosensors expressed in deep brain structures in freely moving mice. When combined with Cre-dependent selective expression of genetically encoded Ca(2+) indicators (GECIs), this system can be used to measure the average neural activity from a specific population of cells in mice performing complex behavioral tasks. As an example, we used viral expression of GCaMPs in striatal projection neurons (SPNs) and recorded the fluorescence changes associated with calcium spikes from mice performing a lever-pressing operant task. The whole procedure, consisting of virus injection, behavior training and optical recording, takes 3-4 weeks to complete. With minor adaptations, this protocol can also be applied to recording cellular events from other cell types in deep brain regions, such as dopaminergic neurons in the ventral tegmental area. The simultaneously recorded fluorescence signals and behavior events can be used to explore the relationship between the neural activity of specific brain circuits and behavior.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kuruma, K.; Takamiya, D.; Ota, Y.

We demonstrate precise and quick detection of the positions of quantum dots (QDs) embedded in two-dimensional photonic crystal nanocavities. We apply this technique to investigate the QD position dependence of the optical coupling between the QD and the nanocavity. We use a scanning electron microscope (SEM) operating at a low acceleration voltage to detect surface bumps induced by the QDs buried underneath. This enables QD detection with a sub-10 nm precision. We then experimentally measure the vacuum Rabi spectra to extract the optical coupling strengths (gs) between single QDs and cavities, and compare them to the values estimated by a combinationmore » of the SEM-measured QD positions and electromagnetic cavity field simulations. We found a highly linear relationship between the local cavity field intensities and the QD-cavity gs, suggesting the validity of the point dipole approximation used in the estimation of the gs. The estimation using SEM has a small standard deviation of ±6.2%, which potentially enables the high accuracy prediction of g prior to optical measurements. Our technique will play a key role for deeply understanding the interaction between QDs and photonic nanostructures and for advancing QD-based cavity quantum electrodynamics.« less

Combined advanced finishing and UV laser conditioning process for producing damage resistant optics

DOEpatents

Menapace, Joseph A.; Peterson, John E.; Penetrante, Bernardino M.; Miller, Philip E.; Parham, Thomas G.; Nichols, Michael A.

2005-07-26

A method for reducing the density of sites on the surface of fused silica optics that are prone to the initiation of laser-induced damage, resulting in optics which have far fewer catastrophic defects, and are better capable of resisting optical deterioration upon exposure to a high-power laser beam.

Three-Axis Distributed Fiber Optic Strain Measurement in 3D Woven Composite Structures

NASA Technical Reports Server (NTRS)

Castellucci, Matt; Klute, Sandra; Lally, Evan M.; Froggatt, Mark E.; Lowry, David

2013-01-01

Recent advancements in composite materials technologies have broken further from traditional designs and require advanced instrumentation and analysis capabilities. Success or failure is highly dependent on design analysis and manufacturing processes. By monitoring smart structures throughout manufacturing and service life, residual and operational stresses can be assessed and structural integrity maintained. Composite smart structures can be manufactured by integrating fiber optic sensors into existing composite materials processes such as ply layup, filament winding and three-dimensional weaving. In this work optical fiber was integrated into 3D woven composite parts at a commercial woven products manufacturing facility. The fiber was then used to monitor the structures during a VARTM manufacturing process, and subsequent static and dynamic testing. Low cost telecommunications-grade optical fiber acts as the sensor using a high resolution commercial Optical Frequency Domain Reflectometer (OFDR) system providing distributed strain measurement at spatial resolutions as low as 2mm. Strain measurements using the optical fiber sensors are correlated to resistive strain gage measurements during static structural loading. Keywords: fiber optic, distributed strain sensing, Rayleigh scatter, optical frequency domain reflectometry

Retinal Optical Coherence Tomography Imaging

NASA Astrophysics Data System (ADS)

Drexler, Wolfgang; Fujimoto, James G.

The eye is essentially transparent, transmitting light with only minimal optical attenuation and scattering providing easy optical access to the anterior segment as well as the retina. For this reason, ophthalmic and especially retinal imaging has been not only the first but also most successful clinical application for optical coherence tomography (OCT). This chapter focuses on the development of OCT technology for retinal imaging. OCT has significantly improved the potential for early diagnosis, understanding of retinal disease pathogenesis, as well as monitoring disease progression and response to therapy. Development of ultrabroad bandwidth light sources and high-speed detection techniques has enabled significant improvements in ophthalmic OCT imaging performance, demonstrating the potential of three-dimensional, ultrahigh-resolution OCT (UHR OCT) to perform noninvasive optical biopsy of the living human retina, i.e., the in vivo visualization of microstructural, intraretinal morphology in situ approaching the resolution of conventional histopathology. Significant improvements in axial resolution and speed not only enable three-dimensional rendering of retinal volumes but also high-definition, two-dimensional tomograms, topographic thickness maps of all major intraretinal layers, as well as volumetric quantification of pathologic intraretinal changes. These advances in OCT technology have also been successfully applied in several animal models of retinal pathologies. The development of light sources emitting at alternative wavelengths, e.g., around #1,060 nm, not only enabled three-dimensional OCT imaging with enhanced choroidal visualization but also improved OCT performance in cataract patients due to reduced scattering losses in this wavelength region. Adaptive optics using deformable mirror technology, with unique high stroke to correct higher-order ocular aberrations, with specially designed optics to compensate chromatic aberration of the human eye, in combination with three-dimensional UHR OCT, recently enabled in vivo cellular resolution retinal imaging.

Advanced materials and techniques for fibre-optic sensing

NASA Astrophysics Data System (ADS)

Henderson, Philip J.

2014-06-01

Fibre-optic monitoring systems came of age in about 1999 upon the emergence of the world's first significant commercialising company - a spin-out from the UK's collaborative MAST project. By using embedded fibre-optic technology, the MAST project successfully measured transient strain within high-performance composite yacht masts. Since then, applications have extended from smart composites into civil engineering, energy, military, aerospace, medicine and other sectors. Fibre-optic sensors come in various forms, and may be subject to embedment, retrofitting, and remote interrogation. The unique challenges presented by each implementation require careful scrutiny before widespread adoption can take place. Accordingly, various aspects of design and reliability are discussed spanning a range of representative technologies that include resonant microsilicon structures, MEMS, Bragg gratings, advanced forms of spectroscopy, and modern trends in nanotechnology. Keywords: Fibre-optic sensors, fibre Bragg gratings, MEMS, MOEMS, nanotechnology, plasmon.

Applications of Optical Microcavity Resonators in Analytical Chemistry

PubMed Central

Wade, James H.; Bailey, Ryan C.

2018-01-01

Optical resonator sensors are an emerging class of analytical technologies that use recirculating light confined within a microcavity to sensitively measure the surrounding environment. Bolstered by advances in microfabrication, these devices can be configured for a wide variety of chemical or biomolecular sensing applications. The review begins with a brief description of optical resonator sensor operation followed by discussions regarding sensor design, including different geometries, choices of material systems, methods of sensor interrogation, and new approaches to sensor operation. Throughout, key recent developments are highlighted, including advancements in biosensing and other applications of optical sensors. Alternative sensing mechanisms and hybrid sensing devices are then discussed in terms of their potential for more sensitive and rapid analyses. Brief concluding statements offer our perspective on the future of optical microcavity sensors and their promise as versatile detection elements within analytical chemistry. PMID:27049629

Low cost, small form factor, and integration as the key features for the optical component industry takeoff

NASA Astrophysics Data System (ADS)

Schiattone, Francesco; Bonino, Stefano; Gobbi, Luigi; Groppi, Angelamaria; Marazzi, Marco; Musio, Maurizio

2003-04-01

In the past the optical component market has been mainly driven by performances. Today, as the number of competitors has drastically increased, the system integrators have a wide range of possible suppliers and solutions giving them the possibility to be more focused on cost and also on footprint reduction. So, if performances are still essential, low cost and Small Form Factor issues are becoming more and more crucial in selecting components. Another evolution in the market is the current request of the optical system companies to simplify the supply chain in order to reduce the assembling and testing steps at system level. This corresponds to a growing demand in providing subassemblies, modules or hybrid integrated components: that means also Integration will be an issue in which all the optical component companies will compete to gain market shares. As we can see looking several examples offered by electronic market, to combine low cost and SFF is a very challenging task but Integration can help in achieving both features. In this work we present how these issues could be approached giving examples of some advanced solutions applied to LiNbO3 modulators. In particular we describe the progress made on automation, new materials and low cost fabrication methods for the parts. We also introduce an approach in integrating optical and electrical functionality on LiNbO3 modulators including RF driver, bias control loop, attenuator and photodiode integrated in a single device.

Material science and Condensed matter Physics. 8th International Conference. Abstracts.

NASA Astrophysics Data System (ADS)

Kulyuk, L. L.; Paladi, Florentin; Canter, Valeriu; Nikorich, Valentina; Filippova, Irina

2016-08-01

The book includes the abstracts of the communications presented at the 8th International Conference on Materials Science and Condensed Matter Physics (MSCMP 2016), a traditional biennial meeting organized by the Institute of Applied Physics of the Academy of Sciences of Moldova (IAP).A total of 346 abstracts has been included in the book. The Conference programm included plenary lectures, topical keynote lectures, contributed oral and poster presentations distributed into 7 sections: * Condensed Matter Theory; * Advanced Bulk Materials; * Design and Structural Characterization of Materials; * Solid State Nanophysics and Nanotechnology; * Energy Conversion and Storage. Solid State Devices; * Surface Engineering and Applied Electrochemistry; * Digital and Optical holography: Materials and Methods. The abstracts are arranged according to the sections mentioned above. The Abstracts book includes a table of matters at the beginning of the book and an index of authors at the finish of the book.

Zernike phase-contrast electron cryotomography applied to marine cyanobacteria infected with cyanophages.

PubMed

Dai, Wei; Fu, Caroline; Khant, Htet A; Ludtke, Steven J; Schmid, Michael F; Chiu, Wah

2014-11-01

Advances in electron cryotomography have provided new opportunities to visualize the internal 3D structures of a bacterium. An electron microscope equipped with Zernike phase-contrast optics produces images with markedly increased contrast compared with images obtained by conventional electron microscopy. Here we describe a protocol to apply Zernike phase plate technology for acquiring electron tomographic tilt series of cyanophage-infected cyanobacterial cells embedded in ice, without staining or chemical fixation. We detail the procedures for aligning and assessing phase plates for data collection, and methods for obtaining 3D structures of cyanophage assembly intermediates in the host by subtomogram alignment, classification and averaging. Acquiring three or four tomographic tilt series takes ∼12 h on a JEM2200FS electron microscope. We expect this time requirement to decrease substantially as the technique matures. The time required for annotation and subtomogram averaging varies widely depending on the project goals and data volume.

Conditionally prepared photon and quantum imaging

NASA Astrophysics Data System (ADS)

Lvovsky, Alexander I.; Aichele, Thomas

2004-10-01

We discuss a classical model allowing one to visualize and characterize the optical mode of the single photon generated by means of a conditional measurement on a biphoton produced in parametric down-conversion. The model is based on Klyshko's advanced wave interpretation, but extends beyond it, providing a precise mathematical description of the advanced wave. The optical mode of the conditional photon is shown to be identical to the mode of the classical difference-frequency field generated due to nonlinear interaction of the partially coherent advanced wave with the pump pulse. With this "nonlinear advanced wave model" most coherence properties of the conditional photon become manifest, which permits one to intuitively understand many recent results, in particular, in quantum imaging.

Advanced Silicon Photonic Transceivers - the Case of a Wavelength Division and Polarization Multiplexed Quadrature Phase Shift Keying Receiver for Terabit/s Optical Transmission

DTIC Science & Technology

2017-03-10

formats by the co- integration of a passive 90 degree optical hybrid, highspeed balanced Ge photodetectors and a high-speed two-channel transimpedance...40 Gbaud and can handle advanced modulation formats by the co-integration of a passive 90 degree optical hybrid, high- speed balanced Ge...reached at an OSNR of 12.4 dB. The hard -decision FEC (HD-FEC) threshold (BER of 3.8 × 10-3 for 7% overhead) requires 14 dB OSNR. For 16-QAM this requires

Advanced miniature processing handware for ATR applications

NASA Technical Reports Server (NTRS)

Chao, Tien-Hsin (Inventor); Daud, Taher (Inventor); Thakoor, Anikumar (Inventor)

2003-01-01

A Hybrid Optoelectronic Neural Object Recognition System (HONORS), is disclosed, comprising two major building blocks: (1) an advanced grayscale optical correlator (OC) and (2) a massively parallel three-dimensional neural-processor. The optical correlator, with its inherent advantages in parallel processing and shift invariance, is used for target of interest (TOI) detection and segmentation. The three-dimensional neural-processor, with its robust neural learning capability, is used for target classification and identification. The hybrid optoelectronic neural object recognition system, with its powerful combination of optical processing and neural networks, enables real-time, large frame, automatic target recognition (ATR).

3D data processing with advanced computer graphics tools

NASA Astrophysics Data System (ADS)

Zhang, Song; Ekstrand, Laura; Grieve, Taylor; Eisenmann, David J.; Chumbley, L. Scott

2012-09-01

Often, the 3-D raw data coming from an optical profilometer contains spiky noises and irregular grid, which make it difficult to analyze and difficult to store because of the enormously large size. This paper is to address these two issues for an optical profilometer by substantially reducing the spiky noise of the 3-D raw data from an optical profilometer, and by rapidly re-sampling the raw data into regular grids at any pixel size and any orientation with advanced computer graphics tools. Experimental results will be presented to demonstrate the effectiveness of the proposed approach.

Thermal and Optical Modulation of the Carrier Mobility in OTFTs Based on an Azo-anthracene Liquid Crystal Organic Semiconductor.

PubMed

Chen, Yantong; Li, Chao; Xu, Xiuru; Liu, Ming; He, Yaowu; Murtaza, Imran; Zhang, Dongwei; Yao, Chao; Wang, Yongfeng; Meng, Hong

2017-03-01

One of the most striking features of organic semiconductors compared with their corresponding inorganic counterparts is their molecular diversity. The major challenge in organic semiconductor material technology is creating molecular structural motifs to develop multifunctional materials in order to achieve the desired functionalities yet to optimize the specific device performance. Azo-compounds, because of their special photoresponsive property, have attracted extensive interest in photonic and optoelectronic applications; if incorporated wisely in the organic semiconductor groups, they can be innovatively utilized in advanced smart electronic applications, where thermal and photo modulation is applied to tune the electronic properties. On the basis of this aspiration, a novel azo-functionalized liquid crystal semiconductor material, (E)-1-(4-(anthracen-2-yl)phenyl)-2-(4-(decyloxy)phenyl)diazene (APDPD), is designed and synthesized for application in organic thin-film transistors (OTFTs). The UV-vis spectra of APDPD exhibit reversible photoisomerizaton upon photoexcitation, and the thin films of APDPD show a long-range orientational order based on its liquid crystal phase. The performance of OTFTs based on this material as well as the effects of thermal treatment and UV-irradiation on mobility are investigated. The molecular structure, stability of the material, and morphology of the thin films are characterized by thermal gravimetric analysis (TGA), polarizing optical microscopy (POM), (differential scanning calorimetry (DSC), UV-vis spectroscopy, atomic force microscopy (AFM), and scanning tunneling microscopy (STM). This study reveals that our new material has the potential to be applied in optical sensors, memories, logic circuits, and functional switches.

Functional analysis and classification of phytoplankton based on data from an automated flow cytometer.

PubMed

Malkassian, Anthony; Nerini, David; van Dijk, Mark A; Thyssen, Melilotus; Mante, Claude; Gregori, Gerald

2011-04-01

Analytical flow cytometry (FCM) is well suited for the analysis of phytoplankton communities in fresh and sea waters. The measurement of light scatter and autofluorescence properties of particles by FCM provides optical fingerprints, which enables different phytoplankton groups to be separated. A submersible version of the CytoSense flow cytometer (the CytoSub) has been designed for in situ autonomous sampling and analysis, making it possible to monitor phytoplankton at a short temporal scale and obtain accurate information about its dynamics. For data analysis, a manual clustering is usually performed a posteriori: data are displayed on histograms and scatterplots, and group discrimination is made by drawing and combining regions (gating). The purpose of this study is to provide greater objectivity in the data analysis by applying a nonmanual and consistent method to automatically discriminate clusters of particles. In other words, we seek for partitioning methods based on the optical fingerprints of each particle. As the CytoSense is able to record the full pulse shape for each variable, it quickly generates a large and complex dataset to analyze. The shape, length, and area of each curve were chosen as descriptors for the analysis. To test the developed method, numerical experiments were performed on simulated curves. Then, the method was applied and validated on phytoplankton cultures data. Promising results have been obtained with a mixture of various species whose optical fingerprints overlapped considerably and could not be accurately separated using manual gating. Copyright © 2011 International Society for Advancement of Cytometry.

Optical Fabrication and Measurement: AR&C and NGST

NASA Technical Reports Server (NTRS)

Martin, Greg; Engelhaupt, Darell

1997-01-01

The need exists at MSFC for research and development within three major areas: (1) Automated Rendezvous and Capture (AR&C) including Video Guidance System (VGS); (2) Next Generation Space Telescope, (NGST); and (3) replicated optics. AR&C/VGS is a laser retroreflection guidance and tracking device which is used from the shuttle to provide video information regarding deployment and guidance of released satellites. NGST is the next large telescope for space to complement Hubble Space Telescope. This will be larger than HST and may be produced in segments to be assembled and aligned in space utilizing advanced mechanisms and materials. The replicated optics will involve a variety of advanced procedures and materials to produce x-ray collimating as well as imaging telescopes and optical components.

Mirror coatings for large aperture UV optical infrared telescope optics

NASA Astrophysics Data System (ADS)

Balasubramanian, Kunjithapatham; Hennessy, John; Raouf, Nasrat; Nikzad, Shouleh; Del Hoyo, Javier; Quijada, Manuel

2017-09-01

Large space telescope concepts such as LUVOIR and HabEx aiming for observations from far UV to near IR require advanced coating technologies to enable efficient gathering of light with important spectral signatures including those in far UV region down to 90nm. Typical Aluminum mirrors protected with MgF2 fall short of the requirements below 120nm. New and improved coatings are sought to protect aluminum from oxidizing readily in normal environment causing severe absorption and reduction of reflectance in the deep UV. Choice of materials and the process of applying coatings present challenges. Here we present the progress achieved to date with experimental investigations of coatings at JPL and at GSFC and discuss the path forward to achieve high reflectance in the spectral region from 90 to 300nm without degrading performance in the visible and NIR regions taking into account durability concerns when the mirrors are exposed to normal laboratory environment as well as high humidity conditions. Reflectivity uniformity required on these mirrors is also discussed.

A Small Angle Scattering Sensor System for the Characterization of Combustion Generated Particulate

NASA Technical Reports Server (NTRS)

Feikema, Douglas A.; Kim, W.; Sivathanu, Yudaya

2007-01-01

One of the critical issues for the US space program is fire safety of the space station and future launch vehicles. A detailed understanding of the scattering signatures of particulate is essential for the development of a false alarm free fire detection system. This paper describes advanced optical instrumentation developed and applied for fire detection. The system is being designed to determine four important physical properties of disperse fractal aggregates and particulates including size distribution, number density, refractive indices, and fractal dimension. Combustion generated particulate are the primary detection target; however, in order to discriminate from other particulate, non-combustion generated particles should also be characterized. The angular scattering signature is measured and analyzed using two photon optical laser scattering. The Rayleigh-Debye-Gans (R-D-G) scattering theory for disperse fractal aggregates is utilized. The system consists of a pulsed laser module, detection module and data acquisition system and software to analyze the signals. The theory and applications are described.

Clinical validity of macular ganglion cell complex by spectral domain-optical coherence tomography in advanced glaucoma.

PubMed

Sung, Mi-Sun; Kang, Byung-Wan; Kim, Hwang-Gyun; Heo, Hwan; Park, Sang-Woo

2014-08-01

To evaluate the repeatability and diagnostic power of macular ganglion cell complex (mGCC) thickness and peripapillary retinal nerve fiber layer (pRNFL) thickness using a spectral domain-optical coherence tomography in advanced glaucoma. Forty advanced glaucoma patients were enrolled. Patients were divided into 2 groups of 20 patients each, according to the MD between -20 and -10 dB, and <-20 dB. The thickness of mGCC and pRNFL were measured with spectral domain-optical coherence tomography in both the groups. The repeatability of each parameter was assessed in both the groups, and the diagnostic power of each parameter was compared with the normal controls. Comparison of diagnostic power between the pRNFL and mGCC parameters revealed that the area under the receiver operating characteristic curve was not significantly different in patients with advanced glaucoma. The repeatability of pRNFL parameters was similar, irrespective of the severity of glaucoma. However, the repeatability of mGCC parameters became lower as the severity increased in patients with advanced glaucoma. In advanced glaucoma, the measurement of mGCC thickness has similar diagnostic power as the measurement of pRNFL thickness. However, the measurement of mGCC thickness showed a lower repeatability as MD decreased.

Advanced In-Pile Instrumentation for Materials Testing Reactors

NASA Astrophysics Data System (ADS)

Rempe, J. L.; Knudson, D. L.; Daw, J. E.; Unruh, T. C.; Chase, B. M.; Davis, K. L.; Palmer, A. J.; Schley, R. S.

2014-08-01

The U.S. Department of Energy sponsors the Advanced Test Reactor (ATR) National Scientific User Facility (NSUF) program to promote U.S. research in nuclear science and technology. By attracting new research users - universities, laboratories, and industry - the ATR NSUF facilitates basic and applied nuclear research and development, advancing U.S. energy security needs. A key component of the ATR NSUF effort is to design, develop, and deploy new in-pile instrumentation techniques that are capable of providing real-time measurements of key parameters during irradiation. This paper describes the strategy developed by the Idaho National Laboratory (INL) for identifying instrumentation needed for ATR irradiation tests and the program initiated to obtain these sensors. New sensors developed from this effort are identified, and the progress of other development efforts is summarized. As reported in this paper, INL researchers are currently involved in several tasks to deploy real-time length and flux detection sensors, and efforts have been initiated to develop a crack growth test rig. Tasks evaluating `advanced' technologies, such as fiber-optics based length detection and ultrasonic thermometers, are also underway. In addition, specialized sensors for real-time detection of temperature and thermal conductivity are not only being provided to NSUF reactors, but are also being provided to several international test reactors.

Improving the Multi-Wavelength Capability of Chandra Large Programs

NASA Astrophysics Data System (ADS)

Pacucci, Fabio

2017-09-01

In order to fully exploit the joint Chandra/JWST/HST ventures to detect faint sources, we urgently need an advanced matching algorithm between optical/NIR and X-ray catalogs/images. This will be of paramount importance in bridging the gap between upcoming optical/NIR facilities (JWST) and later X-ray ones (Athena, Lynx). We propose to develop an advanced and automated tool to improve the identification of Chandra X-ray counterparts detected in deep optical/NIR fields based on T-PHOT, a software widely used in the community. The developed code will include more than 20 years in advancements of X-ray data analysis and will be released to the public. Finally, we will release an updated catalog of X-ray sources in the CANDELS regions: a leap forward in our endeavor of charting the Universe.

No Photon Left Behind: Advanced Optics at ARPA-E for Buildings and Solar Energy

NASA Astrophysics Data System (ADS)

Branz, Howard M.

2015-04-01

Key technology challenges in building efficiency and solar energy utilization require transformational optics, plasmonics and photonics technologies. We describe advanced optical technologies funded by the Advanced Research Projects Agency - Energy. Buildings technologies include a passive daytime photonic cooler, infra-red computer vision mapping for energy audit, and dual-band electrochromic windows based on plasmonic absorption. Solar technologies include novel hybrid energy converters that combine high-efficiency photovoltaics with concentrating solar thermal collection and storage. Because the marginal cost of thermal energy storage is low, these systems enable generation of inexpensive and dispatchable solar energy that can be deployed when the sun doesn't shine. The solar technologies under development include nanoparticle plasmonic spectrum splitting, Rugate filter interference structures and photovoltaic cells that can operate efficiently at over 400° C.

Design and Development of the WVU Advanced Technology Satellite for Optical Navigation

NASA Astrophysics Data System (ADS)

Straub, Miranda

In order to meet the demands of future space missions, it is beneficial for spacecraft to have the capability to support autonomous navigation. This is true for both crewed and uncrewed vehicles. For crewed vehicles, autonomous navigation would allow the crew to safely navigate home in the event of a communication system failure. For uncrewed missions, autonomous navigation reduces the demand on ground-based infrastructure and could allow for more flexible operation. One promising technique for achieving these goals is through optical navigation. To this end, the present work considers how camera images of the Earth's surface could enable autonomous navigation of a satellite in low Earth orbit. Specifically, this study will investigate the use of coastlines and other natural land-water boundaries for navigation. Observed coastlines can be matched to a pre-existing coastline database in order to determine the location of the spacecraft. This paper examines how such measurements may be processed in an on-board extended Kalman filter (EKF) to provide completely autonomous estimates of the spacecraft state throughout the duration of the mission. In addition, future work includes implementing this work on a CubeSat mission within the WVU Applied Space Exploration Lab (ASEL). The mission titled WVU Advanced Technology Satellite for Optical Navigation (WATSON) will provide students with an opportunity to experience the life cycle of a spacecraft from design through operation while hopefully meeting the primary and secondary goals defined for mission success. The spacecraft design process, although simplified by CubeSat standards, will be discussed in this thesis as well as the current results of laboratory testing with the CubeSat model in the ASEL.

Framework for waveband switching in multigranular optical networks: part I-multigranular cross-connect architectures [Invited

NASA Astrophysics Data System (ADS)

Cao, Xiaojun; Anand, Vishal; Qiao, Chunming

2006-12-01

Optical networks using wavelength-division multiplexing (WDM) are the foremost solution to the ever-increasing traffic in the Internet backbone. Rapid advances in WDM technology will enable each fiber to carry hundreds or even a thousand wavelengths (using dense-WDM, or DWDM, and ultra-DWDM) of traffic. This, coupled with worldwide fiber deployment, will bring about a tremendous increase in the size of the optical cross-connects, i.e., the number of ports of the wavelength switching elements. Waveband switching (WBS), wherein wavelengths are grouped into bands and switched as a single entity, can reduce the cost and control complexity of switching nodes by minimizing the port count. This paper presents a detailed study on recent advances and open research issues in WBS networks. In this study, we investigate in detail the architecture for various WBS cross-connects and compare them in terms of the number of ports and complexity and also in terms of how flexible they are in adjusting to dynamic traffic. We outline various techniques for grouping wavelengths into bands for the purpose of WBS and show how traditional wavelength routing is different from waveband routing and why techniques developed for wavelength-routed networks (WRNs) cannot be simply applied to WBS networks. We also outline how traffic grooming of subwavelength traffic can be done in WBS networks. In part II of this study [Cao , submitted to J. Opt. Netw.], we study the effect of wavelength conversion on the performance of WBS networks with reconfigurable MG-OXCs. We present an algorithm for waveband grouping in wavelength-convertible networks and evaluate its performance. We also investigate issues related to survivability in WBS networks and show how waveband and wavelength conversion can be used to recover from failures in WBS networks.

Optical application of electrowetting

NASA Astrophysics Data System (ADS)

He, Mei; Peng, Runling; Chen, Jiabi

2017-02-01

Since electrowetting has been proposed, researchers began to apply eletrowetting into different fields, such as lab-on-chip systems, display technologies, printings and optics etc. This paper mainly introduced structure, theory and application of optical devices based on electrowetting. The optical devices include liquid optical prism, liquid optical lens and display. The paper introduced their principle, specific application and many advantages in optical applications. When they are applied to optical system, production and experiment, they can reduce mechanical moving parts, simplify the structure, operate easily, decrease manufacturing cost and energy consumption, improve working efficiency, and so on. We learn and research them in detail that will contribute to research and develop optical eletrowetting in the future.

Novel applications of photonic signal processing: Temporal cloaking and biphoton pulse shaping

NASA Astrophysics Data System (ADS)

Lukens, Joseph M.

We experimentally demonstrate two innovative applications of photonic technologies previously solidified in the field of classical optical communications. In the first application, we exploit electro-optic modulator technology to develop a novel "time cloak,'' a device which hides events in time by manipulating the flow of a probing light beam. Our temporal cloak is capable of masking high-speed optical data from a receiver, greatly improving the feasibility of time cloaking and bringing such exotic concepts to the verge of practical application. In the second specialization, high-resolution Fourier-transform pulse shaping---perfected for multi-wavelength telecom networks---is applied to shape the correlations of entangled photon pairs, states which have received considerable attention in nonlocal tests of quantum theory and in quantum key distribution. Using nonlinear waveguides fabricated out of periodically poled lithium niobate, we are able to demonstrate ultrafast coincidence detection with record-high efficiency, which coupled with our pulse shaper allows us to realize for the first time several capabilities in biphoton control, including high-order dispersion cancellation, orthogonal spectral coding, correlation train generation, and tunable delay control. Each of these experiments represents an important advance in quantum state manipulation, with the potential to impact developments in quantum information. And more generally, our work introducing telecommunication technology into both temporal cloaking and biphoton control highlights the potential of such tools in more nascent outgrowths of classical and quantum optics.

Small-Field Measurements of 3D Polymer Gel Dosimeters through Optical Computed Tomography.

PubMed

Shih, Tian-Yu; Wu, Jay; Shih, Cheng-Ting; Lee, Yao-Ting; Wu, Shin-Hua; Yao, Chun-Hsu; Hsieh, Bor-Tsung

2016-01-01

With advances in therapeutic instruments and techniques, three-dimensional dose delivery has been widely used in radiotherapy. The verification of dose distribution in a small field becomes critical because of the obvious dose gradient within the field. The study investigates the dose distributions of various field sizes by using NIPAM polymer gel dosimeter. The dosimeter consists of 5% gelatin, 5% monomers, 3% cross linkers, and 5 mM THPC. After irradiation, a 24 to 96 hour delay was applied, and the gel dosimeters were read by a cone beam optical computed tomography (optical CT) scanner. The dose distributions measured by the NIPAM gel dosimeter were compared to the outputs of the treatment planning system using gamma evaluation. For the criteria of 3%/3 mm, the pass rates for 5 × 5, 3 × 3, 2 × 2, 1 × 1, and 0.5 × 0.5 cm2 were as high as 91.7%, 90.7%, 88.2%, 74.8%, and 37.3%, respectively. For the criteria of 5%/5 mm, the gamma pass rates of the 5 × 5, 3 × 3, and 2 × 2 cm2 fields were over 99%. The NIPAM gel dosimeter provides high chemical stability. With cone-beam optical CT readouts, the NIPAM polymer gel dosimeter has potential for clinical dose verification of small-field irradiation.

Advances in highly doped upconversion nanoparticles.

PubMed

Wen, Shihui; Zhou, Jiajia; Zheng, Kezhi; Bednarkiewicz, Artur; Liu, Xiaogang; Jin, Dayong

2018-06-20

Lanthanide-doped upconversion nanoparticles (UCNPs) are capable of converting near-infra-red excitation into visible and ultraviolet emission. Their unique optical properties have advanced a broad range of applications, such as fluorescent microscopy, deep-tissue bioimaging, nanomedicine, optogenetics, security labelling and volumetric display. However, the constraint of concentration quenching on upconversion luminescence has hampered the nanoscience community to develop bright UCNPs with a large number of dopants. This review surveys recent advances in developing highly doped UCNPs, highlights the strategies that bypass the concentration quenching effect, and discusses new optical properties as well as emerging applications enabled by these nanoparticles.

Results from a new 193nm die-to-database reticle inspection platform

NASA Astrophysics Data System (ADS)

Broadbent, William H.; Alles, David S.; Giusti, Michael T.; Kvamme, Damon F.; Shi, Rui-fang; Sousa, Weston L.; Walsh, Robert; Xiong, Yalin

2010-05-01

A new 193nm wavelength high resolution reticle defect inspection platform has been developed for both die-to-database and die-to-die inspection modes. In its initial configuration, this innovative platform has been designed to meet the reticle qualification requirements of the IC industry for the 22nm logic and 3xhp memory generations (and shrinks) with planned extensions to the next generation. The 22nm/3xhp IC generation includes advanced 193nm optical lithography using conventional RET, advanced computational lithography, and double patterning. Further, EUV pilot line lithography is beginning. This advanced 193nm inspection platform has world-class performance and the capability to meet these diverse needs in optical and EUV lithography. The architecture of the new 193nm inspection platform is described. Die-to-database inspection results are shown on a variety of reticles from industry sources; these reticles include standard programmed defect test reticles, as well as advanced optical and EUV product and product-like reticles. Results show high sensitivity and low false and nuisance detections on complex optical reticle designs and small feature size EUV reticles. A direct comparison with the existing industry standard 257nm wavelength inspection system shows measurable sensitivity improvement for small feature sizes

A Proposal to Develop and Test a Fibre-Optic Coupled Solar Thermal Propulsion System for Microsatellites

DTIC Science & Technology

2006-03-01

high numerical aperture fibre optics. Applying fibre optics to STP allows the solar concentrator mirror to be mechanically decoupled from the solar...Applying fibre optics to STP allows the solar concentrator mirror to be mechanically decoupled from the solar heat exchanger as well as granting...concentration is achieved via an optical concentrating system, such as a series of lenses or mirrors . This concentrated sunlight impinges on a blackbody

Applied optics and optical engineering. Volume 9

NASA Astrophysics Data System (ADS)

Shannon, R. R.; Wyant, J. C.

This volume of the series continues the variety of articles which have appeared in the past two volumes. The range of topics runs from the most applied to some fairly complex theory. Basic algorithms for optical engineering are considered along with diffraction gratings, recording and reading of information on optical disks, and the perfect point spread function. An atlas is provided of the imagery which can be expected from telescopes, or other optical systems with nonconventional aperture shapes. A chapter on simulators collects descriptions of the principal types of visual simulators into one article. The optics of the eye is discussed with special emphasis on modern concepts such as contact lenses and automatic refraction. Attention is given to the theory which is of great interest to the applied optical engineer who needs to understand some of the fundamental relations and limitations on image formation by lenses.

National Jet Fuels Combustion Program – Area #3 : Advanced Combustion Tests

DOT National Transportation Integrated Search

2017-12-31

The goal of this study is to develop, conduct, and analyze advanced laser and optical measurements in the experimental combustors developed under ASCENT National Fuel Combustion Program to measure sensitivity to fuel properties. We conducted advanced...

Advances in X-ray optics: From metrology characterization to wavefront sensing-based optimization of active optics

DOE PAGES

Cocco, Daniele; Idir, Mourad; Morton, Daniel; ...

2018-03-20

Experiments using high brightness X-rays are on the forefront of science due to the vast variety of knowledge they can provide. New Synchrotron Radiation (SR) and Free Electron Laser (FEL) light sources provide unique tools for advanced studies using X-rays. Top-level scientists from around the world are attracted to these beamlines to perform unprecedented experiments. High brightness, low emittance light sources allow beamline scientists the possibility to dream up cutting-edge experimental stations. X-ray optics play a key role in bringing the beam from the source to the experimental stations. This paper explores the recent developments in X-ray optics. It touchesmore » on simulations, diagnostics, metrology and adaptive optics, giving an overview of the role X-ray optics have played in the recent past. It will also touch on future developments for one of the most active field in the X-ray science.« less

Advances in X-ray optics: From metrology characterization to wavefront sensing-based optimization of active optics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cocco, Daniele; Idir, Mourad; Morton, Daniel

Experiments using high brightness X-rays are on the forefront of science due to the vast variety of knowledge they can provide. New Synchrotron Radiation (SR) and Free Electron Laser (FEL) light sources provide unique tools for advanced studies using X-rays. Top-level scientists from around the world are attracted to these beamlines to perform unprecedented experiments. High brightness, low emittance light sources allow beamline scientists the possibility to dream up cutting-edge experimental stations. X-ray optics play a key role in bringing the beam from the source to the experimental stations. This paper explores the recent developments in X-ray optics. It touchesmore » on simulations, diagnostics, metrology and adaptive optics, giving an overview of the role X-ray optics have played in the recent past. It will also touch on future developments for one of the most active field in the X-ray science.« less

Metamaterial, plasmonic and nanophotonic devices

NASA Astrophysics Data System (ADS)

Monticone, Francesco; Alù, Andrea

2017-03-01

The field of metamaterials has opened landscapes of possibilities in basic science, and a paradigm shift in the way we think about and design emergent material properties. In many scenarios, metamaterial concepts have helped overcome long-held scientific challenges, such as the absence of optical magnetism and the limits imposed by diffraction in optical imaging. As the potential of metamaterials, as well as their limitations, become clearer, these advances in basic science have started to make an impact on several applications in different areas, with far-reaching implications for many scientific and engineering fields. At optical frequencies, the alliance of metamaterials with the fields of plasmonics and nanophotonics can further advance the possibility of controlling light propagation, radiation, localization and scattering in unprecedented ways. In this review article, we discuss the recent progress in the field of metamaterials, with particular focus on how fundamental advances in this field are enabling a new generation of metamaterial, plasmonic and nanophotonic devices. Relevant examples include optical nanocircuits and nanoantennas, invisibility cloaks, superscatterers and superabsorbers, metasurfaces for wavefront shaping and wave-based analog computing, as well as active, nonreciprocal and topological devices. Throughout the paper, we highlight the fundamental limitations and practical challenges associated with the realization of advanced functionalities, and we suggest potential directions to go beyond these limits. Over the next few years, as new scientific breakthroughs are translated into technological advances, the fields of metamaterials, plasmonics and nanophotonics are expected to have a broad impact on a variety of applications in areas of scientific, industrial and societal significance.

Advanced technology optical telescopes IV; Proceedings of the Meeting, Tucson, AZ, Feb. 12-16, 1990. Parts 1 & 2

NASA Technical Reports Server (NTRS)

Barr, Lawrence D. (Editor)

1990-01-01

The present conference on the current status of large, advanced-technology optical telescope development and construction projects discusses topics on such factors as their novel optical system designs, the use of phased arrays, seeing and site performance factors, mirror fabrication and testing, pointing and tracking techniques, mirror thermal control, structural design strategies, mirror supports and coatings, and the control of segmented mirrors. Attention is given to the proposed implementation of the VLT Interferometer, the first diffraction-limited astronomical images with adaptive optics, a fiber-optic telescope using a large cross-section image-transmitting bundle, the design of wide-field arrays, Hartmann test data reductions, liquid mirrors, inertial drives for telescope pointing, temperature control of large honeycomb mirrors, evaporative coatings for very large telescope mirrors, and the W. M. Keck telescope's primary mirror active control system software.

Advanced optical fiber communication systems

NASA Astrophysics Data System (ADS)

Kazovsky, Leonid G.

1994-03-01

Our research is focused on three major aspects of advanced optical fiber communication systems: dynamic wavelength division multiplexing (WDM) networks, fiber nonlinearities, and high dynamic range coherent analog optical links. In the area of WDM networks, we have designed and implemented two high-speed interface boards and measured their throughput and latency. Furthermore, we designed and constructed an experimental PSK/ASK transceiver that simultaneously transmits packet-switched ASK data and circuit-switched PSK data on the same optical carrier. In the area of fiber nonlinearities, we investigated the theoretical impact of modulation frequency on cross-phase modulation (XPM) in dispersive fibers. In the area of high dynamic range coherent analog optical links, we developed theoretical expressions for the RF power transfer ratio (or RF power gain) and the noise figure (NF) of angle-modulated links. We then compared the RF power gains and noise figures of these links to that of an intensity modulated direct detection (DD) link.

A micropatterning and image processing approach to simplify measurement of cellular traction forces

PubMed Central

Polio, Samuel R.; Rothenberg, Katheryn E.; Stamenović, Dimitrije; Smith, Michael L.

2012-01-01

Quantification of the traction forces that cells apply to their surroundings has been critical to the advancement of our understanding of cancer, development and basic cell biology. This field was made possible through the development of engineered cell culture systems that permit optical measurement of cell-mediated displacements and computational algorithms that allow conversion of these displacements into stresses and forces. Here, we present a novel advancement of traction force microscopy on polyacrylamide (PAA) gels that addresses limitations of existing technologies. Through an indirect patterning technique, we generated PAA gels with fluorescent 1 μm dot markers in a regularized array. This improves existing traction measurements since (i) multiple fields of view can be measured in one experiment without the need for cell removal; (ii) traction vectors are modeled as discrete point forces, and not as a continuous field, using an extremely simple computational algorithm that we have made available online; and (iii) the pattern transfer technique is amenable to any of the published techniques for producing patterns on glass. In the future, this technique will be used for measuring traction forces on complex patterns with multiple, spatially distinct ligands in systems for applying strain to the substrate, and in sandwich cultures that generate quasi-three-dimensional environments for cells. PMID:21884832

Computer Sciences and Data Systems, volume 2

NASA Technical Reports Server (NTRS)

1987-01-01

Topics addressed include: data storage; information network architecture; VHSIC technology; fiber optics; laser applications; distributed processing; spaceborne optical disk controller; massively parallel processors; and advanced digital SAR processors.

Optical coherence tomography - principles and applications

NASA Astrophysics Data System (ADS)

Fercher, A. F.; Drexler, W.; Hitzenberger, C. K.; Lasser, T.

2003-02-01

There have been three basic approaches to optical tomography since the early 1980s: diffraction tomography, diffuse optical tomography and optical coherence tomography (OCT). Optical techniques are of particular importance in the medical field, because these techniques promise to be safe and cheap and, in addition, offer a therapeutic potential. Advances in OCT technology have made it possible to apply OCT in a wide variety of applications but medical applications are still dominating. Specific advantages of OCT are its high depth and transversal resolution, the fact, that its depth resolution is decoupled from transverse resolution, high probing depth in scattering media, contact-free and non-invasive operation, and the possibility to create various function dependent image contrasting methods. This report presents the principles of OCT and the state of important OCT applications. OCT synthesises cross-sectional images from a series of laterally adjacent depth-scans. At present OCT is used in three different fields of optical imaging, in macroscopic imaging of structures which can be seen by the naked eye or using weak magnifications, in microscopic imaging using magnifications up to the classical limit of microscopic resolution and in endoscopic imaging, using low and medium magnification. First, OCT techniques, like the reflectometry technique and the dual beam technique were based on time-domain low coherence interferometry depth-scans. Later, Fourier-domain techniques have been developed and led to new imaging schemes. Recently developed parallel OCT schemes eliminate the need for lateral scanning and, therefore, dramatically increase the imaging rate. These schemes use CCD cameras and CMOS detector arrays as photodetectors. Video-rate three-dimensional OCT pictures have been obtained. Modifying interference microscopy techniques has led to high-resolution optical coherence microscopy that achieved sub-micrometre resolution. This report is concluded with a short presentation of important OCT applications. Ophthalmology is, due to the transparent ocular structures, still the main field of OCT application. The first commercial instrument too has been introduced for ophthalmic diagnostics (Carl Zeiss Meditec AG). Advances in using near-infrared light, however, opened the path for OCT imaging in strongly scattering tissues. Today, optical in vivo biopsy is one of the most challenging fields of OCT application. High resolution, high penetration depth, and its potential for functional imaging attribute to OCT an optical biopsy quality, which can be used to assess tissue and cell function and morphology in situ. OCT can already clarify the relevant architectural tissue morphology. For many diseases, however, including cancer in its early stages, higher resolution is necessary. New broad-bandwidth light sources, like photonic crystal fibres and superfluorescent fibre sources, and new contrasting techniques, give access to new sample properties and unmatched sensitivity and resolution.

GLOBECOM '86 - Global Telecommunications Conference, Houston, TX, Dec. 1-4, 1986, Conference Record. Volumes 1, 2, & 3

NASA Astrophysics Data System (ADS)

Papers are presented on local area networks; formal methods for communication protocols; computer simulation of communication systems; spread spectrum and coded communications; tropical radio propagation; VLSI for communications; strategies for increasing software productivity; multiple access communications; advanced communication satellite technologies; and spread spectrum systems. Topics discussed include Space Station communication and tracking development and design; transmission networks; modulation; data communications; computer network protocols and performance; and coding and synchronization. Consideration is given to free space optical communications systems; VSAT communication networks; network topology design; advances in adaptive filtering echo cancellation and adaptive equalization; advanced signal processing for satellite communications; the elements, design, and analysis of fiber-optic networks; and advances in digital microwave systems.

Exploiting Repulsive and Attractive Optical Forces in Advanced Nanophotonic Systems

DTIC Science & Technology

2015-10-26

in the same device. Such all-optical interaction is achieved without involving any optoelectronic interaction or nonlinear optical effect and thus...other cavity and tilt the see-saw, causing detuning of both cavities but in opposite directions. Furthermore, the see- saw oscillation can “shuttle

Drive to miniaturization: integrated optical networks on mobile platforms

NASA Astrophysics Data System (ADS)

Salour, Michael M.; Batayneh, Marwan; Figueroa, Luis

2011-11-01

With rapid growth of the Internet, bandwidth demand for data traffic is continuing to explode. In addition, emerging and future applications are becoming more and more network centric. With the proliferation of data communication platforms and data-intensive applications (e.g. cloud computing), high-bandwidth materials such as video clips dominating the Internet, and social networking tools, a networking technology is very desirable which can scale the Internet's capability (particularly its bandwidth) by two to three orders of magnitude. As the limits of Moore's law are approached, optical mesh networks based on wavelength-division multiplexing (WDM) have the ability to satisfy the large- and scalable-bandwidth requirements of our future backbone telecommunication networks. In addition, this trend is also affecting other special-purpose systems in applications such as mobile platforms, automobiles, aircraft, ships, tanks, and micro unmanned air vehicles (UAVs) which are becoming independent systems roaming the sky while sensing data, processing, making decisions, and even communicating and networking with other heterogeneous systems. Recently, WDM optical technologies have seen advances in its transmission speeds, switching technologies, routing protocols, and control systems. Such advances have made WDM optical technology an appealing choice for the design of future Internet architectures. Along these lines, scientists across the entire spectrum of the network architectures from physical layer to applications have been working on developing devices and communication protocols which can take full advantage of the rapid advances in WDM technology. Nevertheless, the focus has always been on large-scale telecommunication networks that span hundreds and even thousands of miles. Given these advances, we investigate the vision and applicability of integrating the traditionally large-scale WDM optical networks into miniaturized mobile platforms such as UAVs. We explain the benefits of WDM optical technology for these applications. We also describe some of the limitations of WDM optical networks as the size of a vehicle gets smaller, such as in micro-UAVs, and study the miniaturization and communication system limitations in such environments.

Research Studies on Advanced Optical Module/Head Designs for Optical Data Storage

NASA Technical Reports Server (NTRS)

1992-01-01

Preprints are presented from the recent 1992 Optical Data Storage meeting in San Jose. The papers are divided into the following topical areas: Magneto-optical media (Modeling/design and fabrication/characterization/testing); Optical heads (holographic optical elements); and Optical heads (integrated optics). Some representative titles are as follow: Diffraction analysis and evaluation of several focus and track error detection schemes for magneto-optical disk systems; Proposal for massively parallel data storage system; Transfer function characteristics of super resolving systems; Modeling and measurement of a micro-optic beam deflector; Oxidation processes in magneto-optic and related materials; and A modal analysis of lamellar diffraction gratings in conical mountings.

Preface: phys. stat. sol. (b) 242/13

NASA Astrophysics Data System (ADS)

Esser, Norbert; Zahn, Dietrich R. T.

2005-11-01

Wolfgang Richter celebrated his 65th birthday on 2 January 2005. On such an occasion, usually marking retirement, achievements and breakthroughs in research are reviewed. But Wolfgang Richter is not retiring: he has accepted an offer of a professorship at the University Rome II Tor Vergata. As he explained to us with his famous smile, he plans to concentrate his future efforts even more on his true love in science - the optical diagnostics of interfaces.Wolfgang Richter has been working in the field of optical spectroscopy of solids since his PhD studies at the University of Cologne. Having finished his PhD in 1969 in the field of infrared spectroscopy he decided to reduce the probed volume by increasing the energy of probing photons: Raman spectroscopy! During his postdoctoral and Habilitation periods (1970-1979) at Pennsylvania State University, Max-Planck-Institut für Festkörperforschung, and RWTH Aachen, he pursued his interest in resonance Raman spectroscopy on semiconductors.In 1979 he received his first appointment as full professor at the University of Ulm. He returned to RWTH Aachen in 1981 and discovered his true destiny: semiconductor interfaces. At that time in the Department of Semiconductor Technology, metal-organic vapour phase epitaxy (MOVPE) was under development as a new technique for growing semiconductor layers. The underlying processes in MOVPE were known to be complex and very difficult to analyse with available experimental techniques, due to the unfriendly, reactive gas phase environment. Optical diagnostics turned out to be the key to a better understanding of MOVPE processes. Wolfgang Richter moved from RWTH Aachen to TU Berlin at the end of 1988 and began building a strong research group concentrating on interface analysis from two complementary sides: on the one hand, tracking MOVPE growth processes online by in situ optics and, on the other hand, advancing the fundamental understanding of optical spectra of interfaces by relating the optical response to atomic structures. Combining both aspects has finally led to considerable progress in surface and interface optics, as well as in vapour phase epitaxy and, moreover, the in situ optical tools developed are nowadays available as standard options in commercial MOVPE machines.The advances largely concerned the development of reflectance anisotropy spectroscopy and spectroscopic ellipsometry as in situ optical tools. However, considerable progress in Raman spectroscopy was also made: analysis of surfaces, ultrathin layers down to a single monolayer or even sub-monolayer coverages, and sub-wavelength spatial resolution were demonstrated in recent years. Current challenges concern, in particular, organic materials, molecule-solid interfaces and bio-interfaces, which will help in the development of many new applications and devices. Interfaces will play a crucial role in many of these developments and optical spectroscopy offers promising capabilities for analysing such interfaces. Wolfgang Richter and his group at University of Rome II Tor Vergata are sure to be active in this emerging field for a long time to come.Based on a symposium on Optical Spectroscopy of Interfaces at the Spring Meeting of the German Physical Society in Berlin 2005, we have asked former and present colleagues of Wolfgang Richter to contribute to this special issue of physica status solidi (b) on Advanced Optical Diagnostics of Surfaces, Nanostructures and Ultrathin Films. We think that the collection of 26 papers gives an excellent overview on recent achievements and future developments in the field of linear optics. In addition to a number of Original Papers on experimental work and some Review Articles, the issue includes examples of the current approaches of computational theory to solid state optics and interface optics. We hope that this issue will stimulate the expansion of the growing field of optical analysis of interfaces, nanostructures and ultrathin layers into new areas of basic and applied science. After the success in characterising inorganic materials, it is surely time that the potential of optical spectroscopy techniques for probing thin films and interfaces of composite (organic-inorganic) materials was considered.5 October 2005

Advanced optical blade tip clearance measurement system

NASA Technical Reports Server (NTRS)

Ford, M. J.; Honeycutt, R. E.; Nordlund, R. E.; Robinson, W. W.

1978-01-01

An advanced electro-optical system was developed to measure single blade tip clearances and average blade tip clearances between a rotor and its gas path seal in an operating gas turbine engine. This system is applicable to fan, compressor, and turbine blade tip clearance measurement requirements, and the system probe is particularly suitable for operation in the extreme turbine environment. A study of optical properties of blade tips was conducted to establish measurement system application limitations. A series of laboratory tests was conducted to determine the measurement system's operational performance characteristics and to demonstrate system capability under simulated operating gas turbine environmental conditions. Operational and environmental performance test data are presented.

Analysis of physical layer performance of data center with optical wavelength switches based on advanced modulation formats

NASA Astrophysics Data System (ADS)

Ahmad, Iftikhar; Chughtai, Mohsan Niaz

2018-05-01

In this paper the IRIS (Integrated Router Interconnected spectrally), an optical domain architecture for datacenter network is analyzed. The IRIS integrated with advanced modulation formats (M-QAM) and coherent optical receiver is analyzed. The channel impairments are compensated using the DSP algorithms following the coherent receiver. The proposed scheme allows N2 multiplexed wavelengths for N×N size. The performance of the N×N-IRIS switch with and without wavelength conversion is analyzed for different Baud rates over M-QAM modulation formats. The performance of the system is analyzed in terms of bit error rate (BER) vs OSNR curves.

Recent results and future plans for a 45 actuator adaptive x-ray optics experiment at the advanced light source

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brejnholt, Nicolai F., E-mail: brejnholt1@llnl.gov; Poyneer, Lisa A.; Hill, Randal M.

2016-07-27

We report on the current status of the Adaptive X-ray Optics project run by Lawrence Livermore National Laboratory (LLNL). LLNL is collaborating with the Advanced Light Source (ALS) to demonstrate a near real-time adaptive X-ray optic. To this end, a custom-built 45 cm long deformable mirror has been installed at ALS beamline 5.3.1 (end station 2) for a two-year period that started in September 2014. We will outline general aspects of the instrument, present results from a recent experimental campaign and touch on future plans for the project.

A review on the advances in 3D printing and additive manufacturing of ceramics and ceramic matrix composites for optical applications

NASA Astrophysics Data System (ADS)

Goodman, William A.

2017-09-01

This paper provides a review of advances in 3D printing and additive manufacturing of ceramic and ceramic matrix composites for optical applications. Dr. Goodman has been pioneering additive manufacturing of ceramic matrix composites since 2008. He is the inventor of HoneySiC material, a zero-CTE additively manufactured carbon fiber reinforced silicon carbide ceramic matrix composite, briefly mentioned here. More recently Dr. Goodman has turned his attention to the direct printing of ceramics for optical applications via various techniques including slurry and laser sintering of silicon carbide and other ceramic materials.

Efficient modeling of Bragg coherent x-ray nanobeam diffraction

DOE PAGES

Hruszkewycz, S. O.; Holt, M. V.; Allain, M.; ...

2015-07-02

X-ray Bragg diffraction experiments that utilize tightly focused coherent beams produce complicated Bragg diffraction patterns that depend on scattering geometry, characteristics of the sample, and properties of the x-ray focusing optic. In this paper, we use a Fourier-transform-based method of modeling the 2D intensity distribution of a Bragg peak and apply it to the case of thin films illuminated with a Fresnel zone plate in three different Bragg scattering geometries. Finally, the calculations agree well with experimental coherent diffraction patterns, demonstrating that nanodiffraction patterns can be modeled at nonsymmetric Bragg conditions with this approach—a capability critical for advancing nanofocused x-raymore » diffraction microscopy.« less

Engineering Approaches to Illuminating Brain Structure and Dynamics

PubMed Central

Deisseroth, Karl; Schnitzer, Mark J.

2017-01-01

Historical milestones in neuroscience have come in diverse forms, ranging from the resolution of specific biological mysteries via creative experimentation to broad technological advances allowing neuroscientists to ask new kinds of questions. The continuous development of tools is driven with a special necessity by the complexity, fragility, and inaccessibility of intact nervous systems, such that inventive technique development and application drawing upon engineering and the applied sciences has long been essential to neuroscience. Here we highlight recent technological directions in neuroscience spurred by progress in optical, electrical, mechanical, chemical, and biological engineering. These research areas are poised for rapid growth and will likely be central to the practice of neuroscience well into the future. PMID:24183010

Seeing cilia: imaging modalities for ciliary motion and clinical connections.

PubMed

Peabody, Jacelyn E; Shei, Ren-Jay; Bermingham, Brent M; Phillips, Scott E; Turner, Brett; Rowe, Steven M; Solomon, George M

2018-06-01

The respiratory tract is lined with multiciliated epithelial cells that function to move mucus and trapped particles via the mucociliary transport apparatus. Genetic and acquired ciliopathies result in diminished mucociliary clearance, contributing to disease pathogenesis. Recent innovations in imaging technology have advanced our understanding of ciliary motion in health and disease states. Application of imaging modalities including transmission electron microscopy, high-speed video microscopy, and micron-optical coherence tomography could improve diagnostics and be applied for precision medicine. In this review, we provide an overview of ciliary motion, imaging modalities, and ciliopathic diseases of the respiratory system including primary ciliary dyskinesia, cystic fibrosis, chronic obstructive pulmonary disease, and idiopathic pulmonary fibrosis.

[Ten years retrospective review of the application of digital medical technology in general surgery in China].

PubMed

Fang, C H; Lau, Y Y; Zhou, W P; Cai, W

2017-12-01

Digital medical technology is a powerful tool which has forcefully promoted the development of general surgery in China. In this article, we reviews the application status of three-dimensional visualization and three-dimensional printing technology in general surgery, introduces the development situation of surgical navigation guided by optical and electromagnetic technology and preliminary attempt to combined with mixed reality applied to complicated hepatectomy, looks ahead the development direction of digital medicine in the era of artificial intelligence and big data on behalf of surgical robot and radiomics. Surgeons should proactively master these advanced techniques and accelerate the innovative development of general surgery in China.

Advanced Channeling Technologies in Plasma and Laser Fields

NASA Astrophysics Data System (ADS)

Dabagov, Sultan B.

2018-01-01

Channeling is the phenomenon well known in the world mostly related to the motion of the beams of charged particles in aligned crystals. However, recent studies have shown the feasibility of channeling phenomenology application for description of other various mechanisms of interaction of charged as well as neutral particle beams in solids, plasmas and electromagnetic fields covering the research fields from crystal based undulators, collimators and accelerators to capillary based X-ray and neutron optical elements. This brief review is devoted to the status of channeling-based researches at different centers within international and national collaborations. Present and future possible developments in channeling tools applied to electron interactions in strong plasma and laser fields will be analyzed.

Simultaneous imaging of cellular morphology and multiple biomarkers using an acousto-optic tunable filter-based bright field microscope.

PubMed

Wachman, Elliot S; Geyer, Stanley J; Recht, Joel M; Ward, Jon; Zhang, Bill; Reed, Murray; Pannell, Chris

2014-05-01

An acousto-optic tunable filter (AOTF)-based multispectral imaging microscope system allows the combination of cellular morphology and multiple biomarker stainings on a single microscope slide. We describe advances in AOTF technology that have greatly improved spectral purity, field uniformity, and image quality. A multispectral imaging bright field microscope using these advances demonstrates pathology results that have great potential for clinical use.

Advanced Optical Fibers for High power Fiber lasers

DTIC Science & Technology

2015-08-24

crystal fiber cladding . Advanced Optical Fibers for High Power Fiber Lasers http://dx.doi.org/10.5772/58958 223 lengths above the second-order mode cut...brightness multimode diode lasers for a given pump waveguide dimen‐ sion. In conventional double- clad fibers, low-index polymer coatings are typically used to...was below 0.2. The fiber was passive and there was no laser demonstration in this first attempt. The first cladding - pumping demonstration in an

Quantum memories: emerging applications and recent advances

NASA Astrophysics Data System (ADS)

Heshami, Khabat; England, Duncan G.; Humphreys, Peter C.; Bustard, Philip J.; Acosta, Victor M.; Nunn, Joshua; Sussman, Benjamin J.

2016-11-01

Quantum light-matter interfaces are at the heart of photonic quantum technologies. Quantum memories for photons, where non-classical states of photons are mapped onto stationary matter states and preserved for subsequent retrieval, are technical realizations enabled by exquisite control over interactions between light and matter. The ability of quantum memories to synchronize probabilistic events makes them a key component in quantum repeaters and quantum computation based on linear optics. This critical feature has motivated many groups to dedicate theoretical and experimental research to develop quantum memory devices. In recent years, exciting new applications, and more advanced developments of quantum memories, have proliferated. In this review, we outline some of the emerging applications of quantum memories in optical signal processing, quantum computation and non-linear optics. We review recent experimental and theoretical developments, and their impacts on more advanced photonic quantum technologies based on quantum memories.

Technology development of fabrication techniques for advanced solar dynamic concentrators

NASA Technical Reports Server (NTRS)

Richter, Scott W.

1991-01-01

The objective of the advanced concentrator program is to develop the technology that will lead to lightweight, highly reflective, accurate, scaleable, and long lived space solar dynamic concentrators. The advanced concentrator program encompasses new and innovative concepts, fabrication techniques, materials selection, and simulated space environmental testing. Fabrication techniques include methods of fabricating the substrates and coating substrate surfaces to produce high quality optical surfaces, acceptable for further coating with vapor deposited optical films. The selected materials to obtain a high quality optical surface include microsheet glass and Eccocoat EP-3 epoxy, with DC-93-500 selected as a candidate silicone adhesive and levelizing layer. The following procedures are defined: cutting, cleaning, forming, and bonding microsheet glass. Procedures are also defined for surface cleaning, and EP-3 epoxy application. The results and analyses from atomic oxygen and thermal cycling tests are used to determine the effects of orbital conditions in a space environment.

Quantum memories: emerging applications and recent advances.

PubMed

Heshami, Khabat; England, Duncan G; Humphreys, Peter C; Bustard, Philip J; Acosta, Victor M; Nunn, Joshua; Sussman, Benjamin J

2016-11-12

Quantum light-matter interfaces are at the heart of photonic quantum technologies. Quantum memories for photons, where non-classical states of photons are mapped onto stationary matter states and preserved for subsequent retrieval, are technical realizations enabled by exquisite control over interactions between light and matter. The ability of quantum memories to synchronize probabilistic events makes them a key component in quantum repeaters and quantum computation based on linear optics. This critical feature has motivated many groups to dedicate theoretical and experimental research to develop quantum memory devices. In recent years, exciting new applications, and more advanced developments of quantum memories, have proliferated. In this review, we outline some of the emerging applications of quantum memories in optical signal processing, quantum computation and non-linear optics. We review recent experimental and theoretical developments, and their impacts on more advanced photonic quantum technologies based on quantum memories.

Quantum memories: emerging applications and recent advances

PubMed Central

Heshami, Khabat; England, Duncan G.; Humphreys, Peter C.; Bustard, Philip J.; Acosta, Victor M.; Nunn, Joshua; Sussman, Benjamin J.

2016-01-01

Quantum light–matter interfaces are at the heart of photonic quantum technologies. Quantum memories for photons, where non-classical states of photons are mapped onto stationary matter states and preserved for subsequent retrieval, are technical realizations enabled by exquisite control over interactions between light and matter. The ability of quantum memories to synchronize probabilistic events makes them a key component in quantum repeaters and quantum computation based on linear optics. This critical feature has motivated many groups to dedicate theoretical and experimental research to develop quantum memory devices. In recent years, exciting new applications, and more advanced developments of quantum memories, have proliferated. In this review, we outline some of the emerging applications of quantum memories in optical signal processing, quantum computation and non-linear optics. We review recent experimental and theoretical developments, and their impacts on more advanced photonic quantum technologies based on quantum memories. PMID:27695198

Analysis of leading edge and trailing edge cover glass samples before and after treatment with advanced satellite contamination removal techniques

NASA Technical Reports Server (NTRS)

Hotaling, S. P.

1993-01-01

Two samples from Long Duration Exposure Facility (LDEF) experiment M0003-4 were analyzed for molecular and particulate contamination prior to and following treatment with advanced satellite contamination removal techniques (CO2 gas/solid jet spray and oxygen ion beam). The pre- and post-cleaning measurements and analyses are presented. The jet spray removed particulates in seconds. The low energy reactive oxygen ion beam removed 5,000 A of photo polymerized organic hydrocarbon contamination in less than 1 hour. Spectroscopic analytical techniques were applied to the analysis of cleaning efficiency including: Fourier transform infrared, Auger, x ray photoemissions, energy dispersive x ray, and ultraviolet/visible. The results of this work suggest that the contamination studied here was due to spacecraft self-contamination enhanced by atomic oxygen plasma dynamics and solar UV radiation. These results also suggest the efficacy for the jet spray and ion beam contamination control technologies for spacecraft optical surfaces.

Accelerated Testing Methodology Developed for Determining the Slow Crack Growth of Advanced Ceramics

NASA Technical Reports Server (NTRS)

Choi, Sung R.; Gyekenyesi, John P.

1998-01-01

Constant stress-rate ("dynamic fatigue") testing has been used for several decades to characterize the slow crack growth behavior of glass and structural ceramics at both ambient and elevated temperatures. The advantage of such testing over other methods lies in its simplicity: strengths are measured in a routine manner at four or more stress rates by applying a constant displacement or loading rate. The slow crack growth parameters required for component design can be estimated from a relationship between strength and stress rate. With the proper use of preloading in constant stress-rate testing, test time can be reduced appreciably. If a preload corresponding to 50 percent of the strength is applied to the specimen prior to testing, 50 percent of the test time can be saved as long as the applied preload does not change the strength. In fact, it has been a common, empirical practice in the strength testing of ceramics or optical fibers to apply some preloading (<40 percent). The purpose of this work at the NASA Lewis Research Center is to study the effect of preloading on measured strength in order to add a theoretical foundation to the empirical practice.

Experimental scrambling and noise reduction applied to the optical encryption of QR codes.

PubMed

Barrera, John Fredy; Vélez, Alejandro; Torroba, Roberto

2014-08-25

In this contribution, we implement two techniques to reinforce optical encryption, which we restrict in particular to the QR codes, but could be applied in a general encoding situation. To our knowledge, we present the first experimental-positional optical scrambling merged with an optical encryption procedure. The inclusion of an experimental scrambling technique in an optical encryption protocol, in particular dealing with a QR code "container", adds more protection to the encoding proposal. Additionally, a nonlinear normalization technique is applied to reduce the noise over the recovered images besides increasing the security against attacks. The opto-digital techniques employ an interferometric arrangement and a joint transform correlator encrypting architecture. The experimental results demonstrate the capability of the methods to accomplish the task.

Research advances on potential neurotoxicity of quantum dots.

PubMed

Wu, Tianshu; Zhang, Ting; Chen, Yilu; Tang, Meng

2016-03-01

With rapid development of nanotechnology, quantum dots (QDs) as advanced nanotechnology products have been widely used in biological and biomedical studies, including neuroscience, due to their superior optical properties. In recent years, there has been intense concern regarding the toxicity of QDs with a growing number of studies. However, the knowledge of neurotoxic consequences of QDs applied in living organisms is lagging behind their development, while a potential risk of neurotoxicity arises if mass production of QDs leads to increased exposure and distribution in the nervous system. Owing to the quantum size effect of QDs, they are capable of crossing the blood-brain barrier or moving along neural pathways and entering the brain. Nevertheless, the interactions of QDs with cells and tissues in the central nervous system are not well understood. This review highlighted research advances on the neurotoxicity of QDs in the central nervous system, including oxidative stress injury, elevated cytoplasmic Ca(2+) levels and autophagy to damage in vitro neural cells, and impairments of synaptic transmission and plasticity as well as brain functions in tested animals, with the hope of throwing light on future research directions of QD neurotoxicity, which is a demanding topic that requires further exploration. Copyright © 2015 John Wiley & Sons, Ltd.

Advanced Optical Diagnostic Methods for Describing Fuel Injection and Combustion Flowfield Phenomena

NASA Technical Reports Server (NTRS)

Locke, Randy J.; Hicks, Yolanda R.; Anderson, Robert C.

2004-01-01

Over the past decade advanced optical diagnostic techniques have evolved and matured to a point where they are now widely applied in the interrogation of high pressure combusting flows. At NASA Glenn Research Center (GRC), imaging techniques have been used successfully in on-going work to develop the next generation of commercial aircraft gas turbine combustors. This work has centered on providing a means by which researchers and designers can obtain direct visual observation and measurements of the fuel injection/mixing/combustion processes and combustor flowfield in two- and three-dimensional views at actual operational conditions. Obtaining a thorough understanding of the chemical and physical processes at the extreme operating conditions of the next generation of combustors is critical to reducing emissions and increasing fuel efficiency. To accomplish this and other tasks, the diagnostic team at GRC has designed and constructed optically accessible, high pressurer high temperature flame tubes and sectar rigs capable of optically probing the 20-60 atm flowfields of these aero-combustors. Among the techniques employed at GRC are planar laser-induced fluorescence (PLIF) for imaging molecular species as well as liquid and gaseous fuel; planar light scattering (PLS) for imaging fuel sprays and droplets; and spontaneous Raman scattering for species and temperature measurement. Using these techniques, optical measurements never before possible have been made in the actual environments of liquid fueled gas turbines. 2-D mapping of such parameters as species (e.g. OH-, NO and kerosene-based jet fuel) distribution, injector spray angle, and fuel/air distribution are just some of the measurements that are now routinely made. Optical imaging has also provided prompt feedback to researchers regarding the effects of changes in the fuel injector configuration on both combustor performance and flowfield character. Several injector design modifications and improvements have resulted from this feedback. Alternate diagnostic methods are constantly being evaluated as to their suitability as a diagnostic tool in these environments. A new method currently under examination is background oriented Schlieren (BOS) for examining the fuel/air mixing processes. While ratioing the Stokes and anti-Stokes nitrogen lines obtained from spontaneous Raman is being refined for temperature measurement. While the primary focus of the GRC diagnostic work remains optical species measurement and flow stream characterization, an increased emphasis has been placed on our involvement in flame code validation efforts. A functional combustor code should shorten and streamline future combustor design. Quantitative measurements of flow parameters such as temperature, species concentration, drop size and velocity using such methods as Raman and phase Doppler anemometry will provide data necessary in this effort.

Embedded 100 Gbps Photonic Components

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kuznia, Charlie

This innovation to fiber optic component technology increases the performance, reduces the size and reduces the power consumption of optical communications within dense network systems, such as advanced distributed computing systems and data centers. VCSEL technology is enabling short-reach (< 100 m) and >100 Gbps optical interconnections over multi-mode fiber in commercial applications.

Assessing the future of diffuse optical imaging technologies for breast cancer management

PubMed Central

Tromberg, Bruce J.; Pogue, Brian W.; Paulsen, Keith D.; Yodh, Arjun G.; Boas, David A.; Cerussi, Albert E.

2008-01-01

Diffuse optical imaging (DOI) is a noninvasive optical technique that employs near-infrared (NIR) light to quantitatively characterize the optical properties of thick tissues. Although NIR methods were first applied to breast transillumination (also called diaphanography) nearly 80 years ago, quantitative DOI methods employing time- or frequency-domain photon migration technologies have only recently been used for breast imaging (i.e., since the mid-1990s). In this review, the state of the art in DOI for breast cancer is outlined and a multi-institutional Network for Translational Research in Optical Imaging (NTROI) is described, which has been formed by the National Cancer Institute to advance diffuse optical spectroscopy and imaging (DOSI) for the purpose of improving breast cancer detection and clinical management. DOSI employs broadband technology both in near-infrared spectral and temporal signal domains in order to separate absorption from scattering and quantify uptake of multiple molecular probes based on absorption or fluorescence contrast. Additional dimensionality in the data is provided by integrating and co-registering the functional information of DOSI with x-ray mammography and magnetic resonance imaging (MRI), which provide structural information or vascular flow information, respectively. Factors affecting DOSI performance, such as intrinsic and extrinsic contrast mechanisms, quantitation of biochemical components, image formation∕visualization, and multimodality co-registration are under investigation in the ongoing research NTROI sites. One of the goals is to develop standardized DOSI platforms that can be used as stand-alone devices or in conjunction with MRI, mammography, or ultrasound. This broad-based, multidisciplinary effort is expected to provide new insight regarding the origins of breast disease and practical approaches for addressing several key challenges in breast cancer, including: Detecting disease in mammographically dense tissue, distinguishing between malignant and benign lesions, and understanding the impact of neoadjuvant chemotherapies. PMID:18649477

High-Power, High-Speed Electro-Optic Pockels Cell Modulator

NASA Technical Reports Server (NTRS)

Hawthorne, Justin; Battle, Philip

2013-01-01

Electro-optic modulators rely on a change in the index of refraction for the optical wave as a function of an applied voltage. The corresponding change in index acts to delay the wavefront in the waveguide. The goal of this work was to develop a high-speed, high-power waveguide- based modulator (phase and amplitude) and investigate its use as a pulse slicer. The key innovation in this effort is the use of potassium titanyl phosphate (KTP) waveguides, making the highpower, polarization-based waveguide amplitude modulator possible. Furthermore, because it is fabricated in KTP, the waveguide component will withstand high optical power and have a significantly higher RF modulation figure of merit (FOM) relative to lithium niobate. KTP waveguides support high-power TE and TM modes - a necessary requirement for polarization-based modulation as with a Pockels cell. High-power fiber laser development has greatly outpaced fiber-based modulators in terms of its maturity and specifications. The demand for high-performance nonlinear optical (NLO) devices in terms of power handling, efficiency, bandwidth, and useful wavelength range has driven the development of bulk NLO options, which are limited in their bandwidth, as well as waveguide based LN modulators, which are limited by their low optical damage threshold. Today, commercially available lithium niobate (LN) modulators are used for laser formatting; however, because of photorefractive damage that can reduce transmission and increase requirements on bias control, LN modulators cannot be used with powers over several mW, dependent on wavelength. The high-power, high-speed modulators proposed for development under this effort will enable advancements in several exciting fields including lidarbased remote sensing, atomic interferometry, free-space laser communications, and others.

Hybrid plasmonic electro-optical absorption modulator based on epsilon-near-zero characteristics of ITO

NASA Astrophysics Data System (ADS)

Abdelatty, M. Y.; Badr, M. M.; Swillam, M. A.

2018-03-01

Using transparent conducting oxides (TCOs), like indium-tin-oxide (ITO), for optical modulation attracted research interest because of their epsilon-near-zero (ENZ) characteristics at telecom wavelengths. Utilizing indium-tin-oxide (ITO) in multilayer structure modulators, optical absorption of the active ITO layer can be electrically modulated over a large spectrum range. Although they show advances over common silicon electro-optical modulators (EOMs), they suffer from high insertion losses. To reduce insertion losses and device footprints without sacrificing bandwidth and modulation strength, slot waveguides are promising options because of their high optical confinement. In this paper, we present the study and the design of an electro-optical absorption modulator based on electrically tuning ITO carrier density inside a MOS structure. The device structure is based on dielectric slot waveguide with an ITO plasmonic waveguide modulation section. By changing the dimensions, the effective refractive indices for the slot mode and the off-sate mode of the plasmonic section can be matched. When applying electric field to the plasmonic section (on-state), carriers are generated at the ITO-dielectric interface that result in changing the layer where the electric field is confined from a transparent layer into a lossy layer. A finite difference time domain method with perfect matching layer (PML) absorbing boundary conditions is taken up to simulate and analyze this design. An extinction ratio of 2.3 dB is achieved for a 1-μm-short modulation section, at the telecommunications wavelength (1.55 μm). This EOM has advantages of simple design, easy fabrication, compact size, compatibility with existing silicon photonics platforms, as well as broadband performance.

Time-Of-Flight Camera, Optical Tracker and Computed Tomography in Pairwise Data Registration.

PubMed

Pycinski, Bartlomiej; Czajkowska, Joanna; Badura, Pawel; Juszczyk, Jan; Pietka, Ewa

2016-01-01

A growing number of medical applications, including minimal invasive surgery, depends on multi-modal or multi-sensors data processing. Fast and accurate 3D scene analysis, comprising data registration, seems to be crucial for the development of computer aided diagnosis and therapy. The advancement of surface tracking system based on optical trackers already plays an important role in surgical procedures planning. However, new modalities, like the time-of-flight (ToF) sensors, widely explored in non-medical fields are powerful and have the potential to become a part of computer aided surgery set-up. Connection of different acquisition systems promises to provide a valuable support for operating room procedures. Therefore, the detailed analysis of the accuracy of such multi-sensors positioning systems is needed. We present the system combining pre-operative CT series with intra-operative ToF-sensor and optical tracker point clouds. The methodology contains: optical sensor set-up and the ToF-camera calibration procedures, data pre-processing algorithms, and registration technique. The data pre-processing yields a surface, in case of CT, and point clouds for ToF-sensor and marker-driven optical tracker representation of an object of interest. An applied registration technique is based on Iterative Closest Point algorithm. The experiments validate the registration of each pair of modalities/sensors involving phantoms of four various human organs in terms of Hausdorff distance and mean absolute distance metrics. The best surface alignment was obtained for CT and optical tracker combination, whereas the worst for experiments involving ToF-camera. The obtained accuracies encourage to further develop the multi-sensors systems. The presented substantive discussion concerning the system limitations and possible improvements mainly related to the depth information produced by the ToF-sensor is useful for computer aided surgery developers.

Conceptual design of an on-board optical processor with components

NASA Technical Reports Server (NTRS)

Walsh, J. R.; Shackelford, R. G.

1977-01-01

The specification of components for a spacecraft on-board optical processor was investigated. A space oriented application of optical data processing and the investigation of certain aspects of optical correlators were examined. The investigation confirmed that real-time optical processing has made significant advances over the past few years, but that there are still critical components which will require further development for use in an on-board optical processor. The devices evaluated were the coherent light valve, the readout optical modulator, the liquid crystal modulator, and the image forming light modulator.

Design, analysis and test verification of advanced encapsulation systems, phase 2 program results

NASA Astrophysics Data System (ADS)

Garcia, A.; Minning, C.; Breen, R. T.; Coakley, J. F.; Duncan, L. B.; Gllaspy, D. M.; Kiewert, R. H.; McKinney, F. G.; Taylor, W. E.; Vaughn, L. E.

1982-06-01

Optical, electrical isolation, thermal structural, structural deflection, and thermal tests are reported. The utility of the optical, series capacitance, and structural deflection models was verified.

Design, analysis and test verification of advanced encapsulation systems, phase 2 program results

NASA Technical Reports Server (NTRS)

Garcia, A.; Minning, C.; Breen, R. T.; Coakley, J. F.; Duncan, L. B.; Gllaspy, D. M.; Kiewert, R. H.; Mckinney, F. G.; Taylor, W. E.; Vaughn, L. E.

1982-01-01

Optical, electrical isolation, thermal structural, structural deflection, and thermal tests are reported. The utility of the optical, series capacitance, and structural deflection models was verified.

Astronomy in Denver: Probing Interstellar Circular Polarization with Polvis, a Full Stokes Single Shot Polarimeter

NASA Astrophysics Data System (ADS)

Wolfe, Tristan; Stencel, Robert E.

2018-06-01

Measurements of optical circular polarization (Stokes V) introduced by dust grains in the ISM are important for two main reasons. First of all, the polarization itself contains information about the metallic versus dielectric composition of the dust grains themselves (H. C. van de Hulst 1957, textbook). Additionally, circular polarization can help constrain the interstellar component of the polarization of any source that may have intrinsic polarization, which needs to be calibrated for astrophysical study. Though interstellar circular polarization has been observed (P. G. Martin 1972, MNRAS 159), most broadband measurements of ISM polarization include linear polarization only (Stokes Q and U), due to the relatively low circular polarization signal and the added instrumentation complexity of including V-measurement capability. Prior circular polarization measurements have also received very little follow-up in the past several decades, even as polarimeters have become more accurate due to advances in technology. The University of Denver is pursuing these studies with POLVIS, a prototype polarimeter that utilizes a stress-engineered optic ("SEO", A. K. Spilman and T. G. Brown 2007, Applied Optics IP 46) to produce polarization-dependent PSFs (A. M. Beckley and T. G. Brown 2010, Proc SPIE 7570). These PSFs are analyzed to provide simultaneous Stokes I, Q, U, and V measurements, in a single beam and single image, along the line-of-sight to point source-like objects. Polvis is the first polarimeter to apply these optics and measurement techniques for astronomical observations. We present the first results of this instrument in B, V, and R wavebands, providing a fresh look at full Stokes interstellar polarization. Importantly, this set of efforts will constrain the ISM contribution to the polarization with respect to intrinsic stellar components. The authors are grateful to the estate of William Herschel Womble for the support of astronomy at the University of Denver, and for funding provided by the Mt. Cuba Astronomical Foundation.

Tunable Optical Filters Having Electro-optic Whispering-gallery-mode Resonators

NASA Technical Reports Server (NTRS)

Savchenkov, Anatoliy (Inventor); Ilchenko, Vladimir (Inventor); Matsko, Andrey B. (Inventor); Maleki, Lutfollah (Inventor)

2006-01-01

Tunable optical filters using whispering-gallery-mode (WGM) optical resonators are described. The WGM optical resonator in a filter exhibits an electro-optical effect and hence is tunable by applying a control electrical signal.

Comparative study of the retinal nerve fibre layer thickness performed with optical coherence tomography and GDx scanning laser polarimetry in patients with primary open-angle glaucoma.

PubMed

Wasyluk, Jaromir T; Jankowska-Lech, Irmina; Terelak-Borys, Barbara; Grabska-Liberek, Iwona

2012-03-01

We compared the parameters of retinal nerve fibre layer in patients with advanced glaucoma with the use of different OCT (Optical Coherence Tomograph) devices in relation to analogical measurements performed with GDx VCC (Nerve Fiber Analyzer with Variable Corneal Compensation) scanning laser polarimetry. Study subjects had advanced primary open-angle glaucoma, previously treated conservatively, diagnosed and confirmed by additional examinations (visual field, ophthalmoscopy of optic nerve, gonioscopy), A total of 10 patients were enrolled (9 women and 1 man), aged 18-70 years of age. Nineteen eyes with advanced glaucomatous neuropathy were examined. 1) Performing a threshold perimetry Octopus, G2 strategy and ophthalmoscopy of optic nerve to confirm the presence of advanced primary open-angle glaucoma; 2) performing a GDx VCC scanning laser polarimetry of retinal nerve fibre layer; 3) measuring the retinal nerve fibre layer thickness with 3 different optical coherence tomographs. The parameters of the retinal nerve fibre layer thickness are highly correlated between the GDx and OCT Stratus and 3D OCT-1000 devices in mean retinal nerve fibre layer thickness, retinal nerve fibre layer thickness in the upper sector, and correlation of NFI (GDx) with mean retinal nerve fibre layer thickness in OCT examinations. Absolute values of the retinal nerve fibre layer thickness (measured in µm) differ significantly between GDx and all OCT devices. Examination with OCT devices is a sensitive diagnostic method of glaucoma, with good correlation with the results of GDx scanning laser polarimetry of the patients.

Technical Readiness and Gaps Analysis of Commercial Optical Materials and Measurement Systems for Advanced Small Modular Reactors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anheier, Norman C.; Suter, Jonathan D.; Qiao, Hong

2013-08-06

This report intends to support Department of Energy’s Office of Nuclear Energy (DOE-NE) Nuclear Energy Research and Development Roadmap and industry stakeholders by evaluating optical-based instrumentation and control (I&C) concepts for advanced small modular reactor (AdvSMR) applications. These advanced designs will require innovative thinking in terms of engineering approaches, materials integration, and I&C concepts to realize their eventual viability and deployability. The primary goals of this report include: 1. Establish preliminary I&C needs, performance requirements, and possible gaps for AdvSMR designs based on best available published design data. 2. Document commercial off-the-shelf (COTS) optical sensors, components, and materials in termsmore » of their technical readiness to support essential AdvSMR in-vessel I&C systems. 3. Identify technology gaps by comparing the in-vessel monitoring requirements and environmental constraints to COTS optical sensor and materials performance specifications. 4. Outline a future research, development, and demonstration (RD&D) program plan that addresses these gaps and develops optical-based I&C systems that enhance the viability of future AdvSMR designs. The development of clean, affordable, safe, and proliferation-resistant nuclear power is a key goal that is documented in the Nuclear Energy Research and Development Roadmap. This roadmap outlines RD&D activities intended to overcome technical, economic, and other barriers, which currently limit advances in nuclear energy. These activities will ensure that nuclear energy remains a viable component to this nation’s energy security.« less

Novel EO/IR sensor technologies

NASA Astrophysics Data System (ADS)

Lewis, Keith

2011-10-01

The requirements for advanced EO/IR sensor technologies are discussed in the context of evolving military operations, with significant emphasis on the development of new sensing technologies to meet the challenges posed by asymmetric threats. The Electro-Magnetic Remote Sensing (EMRS DTC) was established in 2003 to provide a centre of excellence in sensor research and development, supporting new capabilities in key military areas such as precision attack, battlespace manoeuvre and information superiority. In the area of advanced electro-optic technology, the DTC has supported work on discriminative imaging, advanced detectors, laser components/technologies, and novel optical techniques. This paper provides a summary of some of the EO/IR technologies explored by the DTC.

Advanced Solar Power Systems

NASA Technical Reports Server (NTRS)

Atkinson, J. H.; Hobgood, J. M.

1984-01-01

The Advanced Solar Power System (ASPS) concentrator uses a technically sophisticated design and extensive tooling to produce very efficient (80 to 90%) and versatile energy supply equipment which is inexpensive to manufacture and requires little maintenance. The advanced optical design has two 10th order, generalized aspheric surfaces in a Cassegrainian configuration which gives outstanding performance and is relatively insensitive to temperature changes and wind loading. Manufacturing tolerances also have been achieved. The key to the ASPS is the direct absorption of concentrated sunlight in the working fluid by radiative transfers in a black body cavity. The basic ASPS design concepts, efficiency, optical system, and tracking and focusing controls are described.

Earth Observing-1 Advanced Land Imager: Radiometric Response Calibration

NASA Technical Reports Server (NTRS)

Mendenhall, J. A.; Lencioni, D. E.; Evans, J. B.

2000-01-01

The Advanced Land Imager (ALI) is one of three instruments to be flown on the first Earth Observing mission (EO-1) under NASA's New Millennium Program (NMP). ALI contains a number of innovative features, including a wide field of view optical design, compact multispectral focal plane arrays, non-cryogenic HgCdTe detectors for the short wave infrared bands, and silicon carbide optics. This document outlines the techniques adopted during ground calibration of the radiometric response of the Advanced Land Imager. Results from system level measurements of the instrument response, signal-to-noise ratio, saturation radiance, and dynamic range for all detectors of every spectral band are also presented.

The theoretical study of passive and active optical devices via planewave based transfer (scattering) matrix method and other approaches

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhuo, Ye

2011-01-01

In this thesis, we theoretically study the electromagnetic wave propagation in several passive and active optical components and devices including 2-D photonic crystals, straight and curved waveguides, organic light emitting diodes (OLEDs), and etc. Several optical designs are also presented like organic photovoltaic (OPV) cells and solar concentrators. The first part of the thesis focuses on theoretical investigation. First, the plane-wave-based transfer (scattering) matrix method (TMM) is briefly described with a short review of photonic crystals and other numerical methods to study them (Chapter 1 and 2). Next TMM, the numerical method itself is investigated in details and developed inmore » advance to deal with more complex optical systems. In chapter 3, TMM is extended in curvilinear coordinates to study curved nanoribbon waveguides. The problem of a curved structure is transformed into an equivalent one of a straight structure with spatially dependent tensors of dielectric constant and magnetic permeability. In chapter 4, a new set of localized basis orbitals are introduced to locally represent electromagnetic field in photonic crystals as alternative to planewave basis. The second part of the thesis focuses on the design of optical devices. First, two examples of TMM applications are given. The first example is the design of metal grating structures as replacements of ITO to enhance the optical absorption in OPV cells (chapter 6). The second one is the design of the same structure as above to enhance the light extraction of OLEDs (chapter 7). Next, two design examples by ray tracing method are given, including applying a microlens array to enhance the light extraction of OLEDs (chapter 5) and an all-angle wide-wavelength design of solar concentrator (chapter 8). In summary, this dissertation has extended TMM which makes it capable of treating complex optical systems. Several optical designs by TMM and ray tracing method are also given as a full complement of this work.« less

Mask manufacturing of advanced technology designs using multi-beam lithography (part 2)

NASA Astrophysics Data System (ADS)

Green, Michael; Ham, Young; Dillon, Brian; Kasprowicz, Bryan; Hur, Ik Boum; Park, Joong Hee; Choi, Yohan; McMurran, Jeff; Kamberian, Henry; Chalom, Daniel; Klikovits, Jan; Jurkovic, Michal; Hudek, Peter

2016-09-01

As optical lithography is extended into 10nm and below nodes, advanced designs are becoming a key challenge for mask manufacturers. Techniques including advanced optical proximity correction (OPC) and Inverse Lithography Technology (ILT) result in structures that pose a range of issues across the mask manufacturing process. Among the new challenges are continued shrinking sub-resolution assist features (SRAFs), curvilinear SRAFs, and other complex mask geometries that are counter-intuitive relative to the desired wafer pattern. Considerable capability improvements over current mask making methods are necessary to meet the new requirements particularly regarding minimum feature resolution and pattern fidelity. Advanced processes using the IMS Multi-beam Mask Writer (MBMW) are feasible solutions to these coming challenges. In this paper, Part 2 of our study, we further characterize an MBMW process for 10nm and below logic node mask manufacturing including advanced pattern analysis and write time demonstration.

Single molecule RNA folding studied with optical trapping

NASA Astrophysics Data System (ADS)

Vieregg, Jeffrey Robert

The RNA folding problem (predicting the equilibrium structure and folding pathway of an RNA molecule from its sequence) is one of the classic problems of biophysics. Recent discoveries of many new functions for RNA have increased its importance, and new instrumental techniques have provided new ways to characterize molecular behavior. In particular, optical trapping (optical tweezers) allows controlled mechanical force to be applied to single RNA molecules while their end-to-end extension is monitored in real time. This enables characterization of RNA folding dynamics at a level unreachable by traditional bulk methods. Furthermore, recent advances in statistical mechanics make it possible to recover equilibrium quantities such as free energy from reactions which occur away from equilibrium. This dissertation describes the application of optical trapping and non-equilibrium statistical mechanics to quantitatively characterize folding of RNA secondary structures. By measuring the folding free energy of several specially designed hairpins in solutions containing various amounts of sodium and potassium, we were able to determine that RNA secondary structure thermodynamics depends not only on monovalent cation concentration but also surprisingly, on species. We also investigated the temperature dependence of hairpin folding thermodynamics and kinetics, which provided a direct measurement of enthalpy and entropy for RNA folding at physiological temperatures. We found that the folding pathway was quite sensitive to both salt and temperature, as measured by the folding success rate of a biologically important hairpin from the HIV-1 viral genome. Finally, I discuss modeling of force-induced RNA folding and unfolding, as well as a series of efforts which have dramatically improved the performance of our optical trapping instrument.

Fabrication of high precision metallic freeform mirrors with magnetorheological finishing (MRF)

NASA Astrophysics Data System (ADS)

Beier, Matthias; Scheiding, Sebastian; Gebhardt, Andreas; Loose, Roman; Risse, Stefan; Eberhardt, Ramona; Tünnermann, Andreas

2013-09-01

The fabrication of complex shaped metal mirrors for optical imaging is a classical application area of diamond machining techniques. Aspherical and freeform shaped optical components up to several 100 mm in diameter can be manufactured with high precision in an acceptable amount of time. However, applications are naturally limited to the infrared spectral region due to scatter losses for shorter wavelengths as a result of the remaining periodic diamond turning structure. Achieving diffraction limited performance in the visible spectrum demands for the application of additional polishing steps. Magnetorheological Finishing (MRF) is a powerful tool to improve figure and finish of complex shaped optics at the same time in a single processing step. The application of MRF as a figuring tool for precise metal mirrors is a nontrivial task since the technology was primarily developed for figuring and finishing a variety of other optical materials, such as glasses or glass ceramics. In the presented work, MRF is used as a figuring tool for diamond turned aluminum lightweight mirrors with electroless nickel plating. It is applied as a direct follow-up process after diamond machining of the mirrors. A high precision measurement setup, composed of an interferometer and an advanced Computer Generated Hologram with additional alignment features, allows for precise metrology of the freeform shaped optics in short measuring cycles. Shape deviations less than 150 nm PV / 20 nm rms are achieved reliably for freeform mirrors with apertures of more than 300 mm. Characterization of removable and induced spatial frequencies is carried out by investigating the Power Spectral Density.

Low-loss interference filter arrays made by plasma-assisted reactive magnetron sputtering (PARMS) for high-performance multispectral imaging

NASA Astrophysics Data System (ADS)

Broßmann, Jan; Best, Thorsten; Bauer, Thomas; Jakobs, Stefan; Eisenhammer, Thomas

2016-10-01

Optical remote sensing of the earth from air and space typically utilizes several channels in the visible and near infrared spectrum. Thin-film optical interference filters, mostly of narrow bandpass type, are applied to select these channels. The filters are arranged in filter wheels, arrays of discrete stripe filters mounted in frames, or patterned arrays on a monolithic substrate. Such multi-channel filter assemblies can be mounted close to the detector, which allows a compact and lightweight camera design. Recent progress in image resolution and sensor sensitivity requires improvements of the optical filter performance. Higher demands placed on blocking in the UV and NIR and in between the spectral channels, in-band transmission and filter edge steepness as well as scattering lead to more complex filter coatings with thicknesses in the range of 10 - 25μm. Technological limits of the conventionally used ion-assisted evaporation process (IAD) can be overcome only by more precise and higher-energetic coating technologies like plasma-assisted reactive magnetron sputtering (PARMS) in combination with optical broadband monitoring. Optics Balzers has developed a photolithographic patterning process for coating thicknesses up to 15μm that is fully compatible with the advanced PARMS coating technology. This provides the possibility of depositing multiple complex high-performance filters on a monolithic substrate. We present an overview of the performance of recently developed filters with improved spectral performance designed for both monolithic filter-arrays and stripe filters mounted in frames. The pros and cons as well as the resulting limits of the filter designs for both configurations are discussed.

Extended depth of focus adaptive optics spectral domain optical coherence tomography

PubMed Central

Sasaki, Kazuhiro; Kurokawa, Kazuhiro; Makita, Shuichi; Yasuno, Yoshiaki

2012-01-01

We present an adaptive optics spectral domain optical coherence tomography (AO-SDOCT) with a long focal range by active phase modulation of the pupil. A long focal range is achieved by introducing AO-controlled third-order spherical aberration (SA). The property of SA and its effects on focal range are investigated in detail using the Huygens-Fresnel principle, beam profile measurement and OCT imaging of a phantom. The results indicate that the focal range is extended by applying SA, and the direction of extension can be controlled by the sign of applied SA. Finally, we demonstrated in vivo human retinal imaging by altering the applied SA. PMID:23082278

Extended depth of focus adaptive optics spectral domain optical coherence tomography.

PubMed

Sasaki, Kazuhiro; Kurokawa, Kazuhiro; Makita, Shuichi; Yasuno, Yoshiaki

2012-10-01

We present an adaptive optics spectral domain optical coherence tomography (AO-SDOCT) with a long focal range by active phase modulation of the pupil. A long focal range is achieved by introducing AO-controlled third-order spherical aberration (SA). The property of SA and its effects on focal range are investigated in detail using the Huygens-Fresnel principle, beam profile measurement and OCT imaging of a phantom. The results indicate that the focal range is extended by applying SA, and the direction of extension can be controlled by the sign of applied SA. Finally, we demonstrated in vivo human retinal imaging by altering the applied SA.

Advanced Wavefront Sensor Concepts.

DTIC Science & Technology

1981-01-01

internal optics (a) Characteristics (see Figure 47) - Intensification with a 256 element linear self scanned diode array - Optical input; lenticular ...34 diameter - Lenticular array input to fiber optics which spread out to tubes - Photon counting for low noise fac- tor (b) Pe r fo rmance - Bialkali...problem in making the lenslet arrays in the pupil divider rectangular. The last optical elements are the lenticular lens arrays. In this group, the first

Advanced Organic Electro-Optic Materials for Integrated Device Applications

DTIC Science & Technology

2001-06-01

Electro - optic chromophores (FTC and CLD) were synthesized in bulk (kilogram) quantities and were distributed to the participants of this program...to stabilize electro - optic activity for operation at elevated temperatures and photon flux levels. Over 100 variants of these chromophores were...1.5-2.0 improvement over FTC and CLD chromophores in terms of electro - optic activity at telecommunication wavelengths. They also have proven more

Thin film ferroelectric electro-optic memory

NASA Technical Reports Server (NTRS)

Thakoor, Sarita (Inventor); Thakoor, Anilkumar P. (Inventor)

1993-01-01

An electrically programmable, optically readable data or memory cell is configured from a thin film of ferroelectric material, such as PZT, sandwiched between a transparent top electrode and a bottom electrode. The output photoresponse, which may be a photocurrent or photo-emf, is a function of the product of the remanent polarization from a previously applied polarization voltage and the incident light intensity. The cell is useful for analog and digital data storage as well as opto-electric computing. The optical read operation is non-destructive of the remanent polarization. The cell provides a method for computing the product of stored data and incident optical data by applying an electrical signal to store data by polarizing the thin film ferroelectric material, and then applying an intensity modulated optical signal incident onto the thin film material to generate a photoresponse therein related to the product of the electrical and optical signals.

Trends in optical coherence tomography applied to medical imaging

NASA Astrophysics Data System (ADS)

Podoleanu, Adrian G.

2014-01-01

The number of publications on optical coherence tomography (OCT) continues to double every three years. Traditionally applied to imaging the eye, OCT is now being extended to fields outside ophthalmology and optometry. Widening its applicability, progress in the core engine of the technology, and impact on development of novel optical sources, make OCT a very active and rapidly evolving field. Trends in the developments of different specific devices, such as optical sources, optical configurations and signal processing will be presented. Encompassing studies on both the configurations as well as on signal processing themes, current research in Kent looks at combining spectral domain with time domain imaging for long axial range and simultaneous imaging at several depths. Results of the collaborative work of the Applied Optics Group in Kent with organisers of this conference will be presented, with reference to 3D monitoring of abfraction.

The Mars Microbeam Raman Spectrometer: An Improved Advanced Brassboard

NASA Technical Reports Server (NTRS)

Haskin, L. A.; Wang, Alian

2003-01-01

An advanced brassboard (ADBB) of the Mars Miscrobeam Raman Spectrometer is being developed. The probe and spectrograph have been redesigned with improved optics and the electronics have been miniaturized. The modified optical design in the probe and spectrograph provides better spectral resolution than the previous model and enables the probe design to be more compatible with robotic arm deployment. The CCD detector is now cooled thermoelectrically in anticipation of eventual terrestrial field testing of the instrument.

Chirp-enhanced fast light in semiconductor optical amplifiers.

PubMed

Sedgwick, F G; Pesala, Bala; Uskov, Alexander V; Chang-Hasnain, C J

2007-12-24

We present a novel scheme to increase the THz-bandwidth fast light effect in semiconductor optical amplifiers and increase the number of advanced pulses. By introducing a linear chirp to the input pulses before the SOA and recompressing at the output with an opposite chirp, the advance-bandwidth product reached 3.5 at room temperature, 1.55 microm wavelength. This is the largest number reported, to the best of our knowledge, for a semiconductor slow/fast light device.

Advanced instrumentation for next-generation aerospace propulsion control systems

NASA Technical Reports Server (NTRS)

Barkhoudarian, S.; Cross, G. S.; Lorenzo, Carl F.

1993-01-01

New control concepts for the next generation of advanced air-breathing and rocket engines and hypersonic combined-cycle propulsion systems are analyzed. The analysis provides a database on the instrumentation technologies for advanced control systems and cross matches the available technologies for each type of engine to the control needs and applications of the other two types of engines. Measurement technologies that are considered to be ready for implementation include optical surface temperature sensors, an isotope wear detector, a brushless torquemeter, a fiberoptic deflectometer, an optical absorption leak detector, the nonintrusive speed sensor, and an ultrasonic triducer. It is concluded that all 30 advanced instrumentation technologies considered can be recommended for further development to meet need of the next generation of jet-, rocket-, and hypersonic-engine control systems.

Grain optical properties

NASA Technical Reports Server (NTRS)

Hanner, Martha

1988-01-01

The optical properties of small grains provide the link between the infrared observations presented in Chapter 1 and the dust composition described in Chapter 3. In this session, the optical properties were discussed from the viewpoint of modeling the emission from the dust coma and the scattering in order to draw inference about the dust size distribution and composition. The optical properties are applied to the analysis of the infrared data in several ways, and these different uses should be kept in mind when judging the validity of the methods for applying optical constants to real grains.

[The design and application of domestic mid-IR fiber optics].

PubMed

Weng, Shi-fu; Gao, Jian-ping; Xu, Yi-zhuang; Yang, Li-min; Bian, Bei-ya; Xiang, Hai-bo; Wu, Jin-guang

2004-05-01

The combination of mid-IR fiber optics and FTIR has made the non-invasive determination of samples in situ, with long distances, and in vivo possible. In this paper domestic mid-IR fiber optics was improved to investigate the transmission ability of fiber optics and its application to the sample determination. New design was applied to obtaining one bare fiber optics, which has a minor energy loss and higher signal-to-noise ratio. The spectra of H2O/EtOH and tissue samples were measured using the new designed fiber optics and the results show that home-made mid-IR fiber optics can be applied to the field of determination of general and biological samples.

Research on fabrication of aspheres at the Center of Optics Technology (University of Applied Science in Aalen); Techical Digest

NASA Astrophysics Data System (ADS)

Boerret, Rainer; Burger, Jochen; Bich, Andreas; Gall, Christoph; Hellmuth, Thomas

2005-05-01

The Center of Optics Technology at the University of Applied Science, founded in 2003, is part of the School of Optics and Mechatronics. It completes the existing optical engineering department with a full optical fabrication and metrology chain and serves in parallel as a technology transfer center, to provide area industries with the most up-to-date technology in optical fabrication and engineering. Two examples of research work will be presented. The first example is the optimizing of the grinding process for high precision aspheres, the other is generating and polishing of a freeform optical element which is used as a phase plate.

Research on fabrication of aspheres at the Center of Optics Technology (University of Applied Science in Aalen); Techical Digest

NASA Astrophysics Data System (ADS)

Boerret, Rainer; Burger, Jochen; Bich, Andreas; Gall, Christoph; Hellmuth, Thomas

2005-05-01

The Center of Optics Technology at the University of Applied Science, founded in 2003, is part of the School of Optics & Mechatronics. It completes the existing optical engineering department with a full optical fabrication and metrology chain and serves in parallel as a technology transfer center, to provide area industries with the most up-to-date technology in optical fabrication and engineering. Two examples of research work will be presented. The first example is the optimizing of the grinding process for high precision aspheres, the other is generating and polishing of a freeform optical element which is used as a phase plate.

Micro-optics technology and sensor systems applications

NASA Technical Reports Server (NTRS)

Gal, George; Herman, B.; Anderson, W.; Whitney, R.; Morrow, H.

1993-01-01

The current generation of electro-optical sensors utilizing refractive and reflective optical elements require sophisticated, complex, and expensive designs. Advanced-technology-based electro-optical sensors of minimum size and weight require miniaturization of optical, electrical, and mechanical devices with an increasing trend toward integration of various components. Micro-optics technology has the potential in a number of areas to simplify optical design with improved performance. This includes internally cooled apertures, hybrid optical design, microlenses, dispersive multicolor microlenses, active dither, electronically controlled optical beam steer, and microscopic integration of micro-optics, detectors, and signal processing layers. This paper describes our approach to the development of micro-optics technology with our main emphasis for sensors applications.

Advanced optical measuring systems for measuring the properties of fluids and structures

NASA Technical Reports Server (NTRS)

Decker, A. J.

1986-01-01

Four advanced optical models are reviewed for the measurement of visualization of flow and structural properties. Double-exposure, diffuse-illumination, holographic interferometry can be used for three-dimensional flow visualization. When this method is combined with optical heterodyning, precise measurements of structural displacements or fluid density are possible. Time-average holography is well known as a method for displaying vibrational mode shapes, but it also can be used for flow visualization and flow measurements. Deflectometry is used to measure or visualize the deflection of light rays from collimation. Said deflection occurs because of refraction in a fluid or because of reflection from a tilted surface. The moire technique for deflectometry, when combined with optical heterodyning, permits very precise measurements of these quantities. The rainbow schlieren method of deflectometry allows varying deflection angles to be encoded with colors for visualization.

Advanced optical manufacturing and testing; Proceedings of the Meeting, San Diego, CA, July 9-11, 1990

NASA Astrophysics Data System (ADS)

Sanger, Gregory M.; Reid, Paul B.; Baker, Lionel R.

1990-11-01

Consideration is given to advanced optical fabrication, profilometry and thin films, and metrology. Particular attention is given to automation for optics manufacturing, 3D contouring on a numerically controlled grinder, laser-scanning lens configurations, a noncontact precision measurement system, novel noncontact profiler design for measuring synchrotron radiation mirrors, laser-diode technologies for in-process metrology, measurements of X-ray reflectivities of Au-coatings at several energies, platinum coating of an X-ray mirror for SR lithography, a Hilbert transform algorithm for fringe-pattern analysis, structural error sources during fabrication of the AXAF optical elements, an in-process mirror figure qualification procedure for large deformable mirrors, interferometric evaluation of lenslet arrays for 2D phase-locked laser diode sources, and manufacturing and metrology tooling for the solar-A soft X-ray telescope.

Application of fluorescence spectroscopy and imaging in the detection of a photosensitizer in photodynamic therapy

NASA Astrophysics Data System (ADS)

Zang, Lixin; Zhao, Huimin; Zhang, Zhiguo; Cao, Wenwu

2017-02-01

Photodynamic therapy (PDT) is currently an advanced optical technology in medical applications. However, the application of PDT is limited by the detection of photosensitizers. This work focuses on the application of fluorescence spectroscopy and imaging in the detection of an effective photosenzitizer, hematoporphyrin monomethyl ether (HMME). Optical properties of HMME were measured and analyzed based on its absorption and fluorescence spectra. The production mechanism of its fluorescence emission was analyzed. The detection device for HMME based on fluorescence spectroscopy was designed. Ratiometric method was applied to eliminate the influence of intensity change of excitation sources, fluctuates of excitation sources and photo detectors, and background emissions. The detection limit of this device is 6 μg/L, and it was successfully applied to the diagnosis of the metabolism of HMME in the esophageal cancer cells. To overcome the limitation of the point measurement using fluorescence spectroscopy, a two-dimensional (2D) fluorescence imaging system was established. The algorithm of the 2D fluorescence imaging system is deduced according to the fluorescence ratiometric method using bandpass filters. The method of multiple pixel point addition (MPPA) was used to eliminate fluctuates of signals. Using the method of MPPA, SNR was improved by about 30 times. The detection limit of this imaging system is 1.9 μg/L. Our systems can be used in the detection of porphyrins to improve the PDT effect.

Applied Optics growth: 1991-1999.

PubMed

Murray, John R

2012-07-20

A commemorative editorial for the 50th anniversary of Applied Optics describes the journal's growth during the 1990s including internationalization of authors and editors as well as the rise of the Internet.

A Novel Variable-Focus Lens for HFGW

NASA Astrophysics Data System (ADS)

Woods, R. Clive

2006-01-01

Li and Torr published calculations claiming to show that gravitational waves (GWs) propagate inside superconductors with a phase velocity reduction (compared to free space) by a factor n ~ 300× and a wavenumber increase by a factor n. This gives major opportunities for designing future GW components able to focus, refract, reflect, and otherwise manipulate gravitational waves for efficient coupling to detectors, transmitters, generators, resonant chambers, and other sensors. To exploit this result, a novel type of HFGW lens design is proposed here using a magnetic field to adjust the focal length in an infinitely-variable manner. Type-II superconductors do not always completely expel large magnetic fields; above their lower critical field they allow vortices of magnetic flux to channel the magnetic field through the material. Within these vortices, the superconductor is magnetically quenched and so behaves as a non-superconductor. Varying the applied magnetic field varies the proportion of material that is quenched. This subsequently affects GW propagation behavior through a type II superconductor. Therefore, using a suitable non-uniform magnetic field, the GW optical path length may be arranged to vary in a technologically useful manner. A GW lens may be designed with focal length dependent upon the applied magnetic field. Such a lens would be invaluable in the design of advanced GW optics since focusing will be achieved electrically with no moving parts; for this reason it would be unparalleled in conventional optics. Since, therefore, variations in n (due to calculation error limits) can be compensated electrically, successful demonstration of this device would confirm the Li and Torr prediction much more easily than directly using a fixed lens structure. The device would also enable fast auto-focusing, zooming, and imaging tomography using electronic servos following development of the necessary HFGW detectors.

Color changing plasmonic surfaces utilizing liquid crystal (Conference Presentation)

NASA Astrophysics Data System (ADS)

Franklin, Daniel; Wu, Shin-Tson; Chanda, Debashis

2016-09-01

Plasmonic structural color has recently garnered significant interest as an alternative to the organic dyes standard in print media and liquid crystal displays. These nanostructured metallic systems can produce diffraction limited images, be made polarization dependent, and exhibit resistance to color bleaching. Perhaps even more advantageous, their optical characteristics can also be tuned, post-fabrication, by altering the surrounding media's refractive index parallel to the local plasmonic fields. A common material with which to achieve this is liquid crystal. By reorienting the liquid crystal molecules through external electric fields, the optical resonances of the plasmonic filters can be dynamically controlled. Demonstrations of this phenomenon, however, have been limited to modest shifts in plasmon resonance. Here, we report a liquid crystal-plasmonic system with an enhanced tuning range through the use of a shallow array of nano-wells and high birefringent liquid crystal. The continuous metallic nanostructure maximizes the overlap between plasmonic fields and liquid crystal while also allowing full reorientation of the liquid crystal upon an applied electric field. Sweeping over structural dimensions and voltages results in a color palette for these dynamic reflective pixels that can further be exploited to create color tunable images. These advances make plasmonic-liquid crystal systems more attractive candidates for filter, display, and other tunable optical technologies.

Background-Free 3D Nanometric Localization and Sub-nm Asymmetry Detection of Single Plasmonic Nanoparticles by Four-Wave Mixing Interferometry with Optical Vortices

NASA Astrophysics Data System (ADS)

Zoriniants, George; Masia, Francesco; Giannakopoulou, Naya; Langbein, Wolfgang; Borri, Paola

2017-10-01

Single nanoparticle tracking using optical microscopy is a powerful technique with many applications in biology, chemistry, and material sciences. Despite significant advances, localizing objects with nanometric position precision in a scattering environment remains challenging. Applied methods to achieve contrast are dominantly fluorescence based, with fundamental limits in the emitted photon fluxes arising from the excited-state lifetime as well as photobleaching. Here, we show a new four-wave-mixing interferometry technique, whereby the position of a single nonfluorescing gold nanoparticle of 25-nm radius is determined with 16 nm precision in plane and 3 nm axially from rapid single-point measurements at 1-ms acquisition time by exploiting optical vortices. The precision in plane is consistent with the photon shot-noise, while axially it is limited by the nano-positioning sample stage, with an estimated photon shot-noise limit of 0.5 nm. The detection is background-free even inside biological cells. The technique is also uniquely sensitive to particle asymmetries of only 0.5% ellipticity, corresponding to a single atomic layer of gold, as well as particle orientation. This method opens new ways of unraveling single-particle trafficking within complex 3D architectures.

Challenges to Laser-Based Imaging Techniques in Gas Turbine Combustor Systems for Aerospace Applications

NASA Technical Reports Server (NTRS)

Locke, Randy J.; Anderson, Robert C.; Zaller, Michelle M.; Hicks, Yolanda R.

1998-01-01

Increasingly severe constraints on emissions, noise and fuel efficiency must be met by the next generation of commercial aircraft powerplants. At NASA Lewis Research Center (LeRC) a cooperative research effort with industry is underway to design and test combustors that will meet these requirements. To accomplish these tasks, it is necessary to gain both a detailed understanding of the combustion processes and a precise knowledge of combustor and combustor sub-component performance at close to actual conditions. To that end, researchers at LeRC are engaged in a comprehensive diagnostic investigation of high pressure reacting flowfields that duplicate conditions expected within the actual engine combustors. Unique, optically accessible flame-tubes and sector rig combustors, designed especially for these tests. afford the opportunity to probe these flowfields with the most advanced, laser-based optical diagnostic techniques. However, these same techniques, tested and proven on comparatively simple bench-top gaseous flame burners, encounter numerous restrictions and challenges when applied in these facilities. These include high pressures and temperatures, large flow rates, liquid fuels, remote testing, and carbon or other material deposits on combustor windows. Results are shown that document the success and versatility of these nonintrusive optical diagnostics despite the challenges to their implementation in realistic systems.

Fiber optic sensor for continuous health monitoring in CFRP composite materials

NASA Astrophysics Data System (ADS)

Rippert, Laurent; Papy, Jean-Michel; Wevers, Martine; Van Huffel, Sabine

2002-07-01

An intensity modulated sensor, based on the microbending concept, has been incorporated in laminates produced from a C/epoxy prepreg. Pencil lead break tests (Hsu-Neilsen sources) and tensile tests have been performed on this material. In this research study, fibre optic sensors will be proven to offer an alternative for the robust piezoelectric transducers used for Acoustic Emission (AE) monitoring. The main emphasis has been put on the use of advanced signal processing techniques based on time-frequency analysis. The signal Short Time Fourier Transform (STFT) has been computed and several robust noise reduction algorithms, such as Wiener adaptive filtering, improved spectral subtraction filtering, and Singular Value Decomposition (SVD) -based filtering, have been applied. An energy and frequency -based detection criterion is put forward to detect transient signals that can be correlated with Modal Acoustic Emission (MAE) results and thus damage in the composite material. There is a strong indication that time-frequency analysis and the Hankel Total Least Squares (HTLS) method can also be used for damage characterization. This study shows that the signal from a quite simple microbend optical sensor contains information on the elastic energy released whenever damage is being introduced in the host material by mechanical loading. Robust algorithms can be used to retrieve and analyze this information.

Simultaneous calculation of three optical surfaces in the 3D SMS freeform RXI optic

NASA Astrophysics Data System (ADS)

Sorgato, Simone; Chaves, Julio; Mohedano, Rubén.; Hernández, Maikel; Blen, José; Benitez, Pablo; Miñano, Juan C.; Grabovickic, Dejan; Thienpont, Hugo; Duerr, Fabian

2016-09-01

The Freeform RXI collimator is a remarkable example of advanced nonimaging device designed with the 3D Simultaneous Multiple Surface (SMS) Method. In the original design, two (the front refracting surface and the back mirror) of the three optical surfaces of the RXI are calculated simultaneously and one (the cavity surrounding the source) is fixed by the designer. As a result, the RXI perfectly couples two input wavefronts (coming from the edges of the extended LED source) with two output wavefronts (defining the output beam). This allows for LED lamps able to produce controlled intensity distributions, which can and have been successfully applied to demanding applications like high- and low-beams for Automotive Lighting. Nevertheless, current trends in this field are moving towards smaller headlamps with more shape constraints driven by car design. We present an improved version of the 3D RXI in which also the cavity surface is computed during the design, so that there are three freeform surfaces calculated simultaneously and an additional degree of freedom for controlling the light emission: now the RXI can perfectly couple three input wavefronts with three output wavefronts. The enhanced control over ray beams allows for improved light homogeneity and better pattern definition.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Novotny, Lukas

The seventh conference in the NFO conference series, held here in Rochester, provided to be the principal forum for advances in sub-wavelength optics, near-field optical microscopy, local field enhancement, instrumental developments and the ever-increasing range of applications. This conference brought together the diverse scientific communities working on the theory and application of near-field optics (NFO) and related techniques.

Optical Coherence Microscopy

NASA Astrophysics Data System (ADS)

Aguirre, Aaron D.; Zhou, Chao; Lee, Hsiang-Chieh; Ahsen, Osman O.; Fujimoto, James G.

Cellular imaging of human tissues remains an important advance for many clinical applications of optical coherence tomography (OCT). Imaging cells with traditional OCT systems has not been possible due to the limited transverse resolution of such techniques. Optical coherence microscopy (OCM) refers to OCT methods that achieve high transverse resolution to visualize cells and subcellular features. This chapter provides a comprehensive discussion of the rationale for cellular imaging in human tissues as well as a review of the key technological advances required to achieve it. Time domain and Fourier domain OCM approaches are described with an emphasis on state of the art system designs, including miniaturized endoscopic imaging probes. Clinical applications are discussed and multiple examples of cellular imaging in human tissues are provided.

Fabrication technology

NASA Astrophysics Data System (ADS)

1988-05-01

Many laboratory programs continue to need optical components of ever-increasing size and accuracy. Unfortunately, optical surfaces produced by the conventional sequence of grinding, lapping, and polishing can become prohibitively expensive. Research in the Fabrication Technology area focuses on methods of fabricating components with heretofore unrealized levels of precision. In FY87, researchers worked to determine the fundamental mechanical limits of material removal, experimented with unique material removal and deposition processes, developed servo systems for controlling the geometric position of ultraprecise machine tools, and advanced the ability to precisely measure contoured workpieces. Continued work in these areas will lead to more cost-effective processes to fabricate even higher quality optical components for advanced lasers and for visible, ultraviolet, and X-ray diagnostic systems.

Optics outreach in Irish context

NASA Astrophysics Data System (ADS)

McHugh, Emer; Smith, Arlene

2009-06-01

The Applied Optics Group, National University of Ireland Galway is a research centre involved in programmes that cover a wide variety of topics in applied optics and imaging science, including smart optics, adaptive optics, optical scattering and propagation, and engineering optics. The Group have also developed significant outreach programmes both in Primary and Post-Primary schools. It is recognised that there is a need for innovation in Science Education in Ireland and we are committed to working extensively with schools. The main aim of these outreach programmes is to increase awareness and interest in science with students and enhance the communication skills of the researchers working in the Group. The education outreach team works closely with the relevant teachers in both Primary and Post-Primary schools to design and develop learning initiatives to match the needs of the target group of students. The learning programmes are usually delivered in the participating schools during normal class time by a team of Applied Optics specialists. We are involved in running these programmes in both Primary and Post-Primary schools where the programmes are tailored to the curriculum and concentrating on optics and light. The students may also visit the Groups research centre where presentations and laboratory tours are arranged.

Single-walled carbon nanotubes as near-infrared optical biosensors for life sciences and biomedicine.

PubMed

Jain, Astha; Homayoun, Aida; Bannister, Christopher W; Yum, Kyungsuk

2015-03-01

Single-walled carbon nanotubes that emit photostable near-infrared fluorescence have emerged as near-infrared optical biosensors for life sciences and biomedicine. Since the discovery of their near-infrared fluorescence, researchers have engineered single-walled carbon nanotubes to function as an optical biosensor that selectively modulates its fluorescence upon binding of target molecules. Here we review the recent advances in the single-walled carbon nanotube-based optical sensing technology for life sciences and biomedicine. We discuss the structure and optical properties of single-walled carbon nanotubes, the mechanisms for molecular recognition and signal transduction in single-walled carbon nanotube complexes, and the recent development of various single-walled carbon nanotube-based optical biosensors. We also discuss the opportunities and challenges to translate this emerging technology into biomedical research and clinical use, including the biological safety of single-walled carbon nanotubes. The advances in single-walled carbon nanotube-based near-infrared optical sensing technology open up a new avenue for in vitro and in vivo biosensing with high sensitivity and high spatial resolution, beneficial for many areas of life sciences and biomedicine. Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Developments in optical modeling methods for metrology

NASA Astrophysics Data System (ADS)

Davidson, Mark P.

1999-06-01

Despite the fact that in recent years the scanning electron microscope has come to dominate the linewidth measurement application for wafer manufacturing, there are still many applications for optical metrology and alignment. These include mask metrology, stepper alignment, and overlay metrology. Most advanced non-optical lithographic technologies are also considering using topics for alignment. In addition, there have been a number of in-situ technologies proposed which use optical measurements to control one aspect or another of the semiconductor process. So optics is definitely not dying out in the semiconductor industry. In this paper a description of recent advances in optical metrology and alignment modeling is presented. The theory of high numerical aperture image simulation for partially coherent illumination is discussed. The implications of telecentric optics on the image simulation is also presented. Reciprocity tests are proposed as an important measure of numerical accuracy. Diffraction efficiencies for chrome gratings on reticles are one good way to test Kirchoff's approximation as compared to rigorous calculations. We find significant differences between the predictions of Kirchoff's approximation and rigorous methods. The methods for simulating brightfield, confocal, and coherence probe microscope imags are outlined, as are methods for describing aberrations such as coma, spherical aberration, and illumination aperture decentering.

Optically efficient InAsSb nanowires for silicon-based mid-wavelength infrared optoelectronics.

PubMed

Zhuang, Q D; Alradhi, H; Jin, Z M; Chen, X R; Shao, J; Chen, X; Sanchez, Ana M; Cao, Y C; Liu, J Y; Yates, P; Durose, K; Jin, C J

2017-03-10

InAsSb nanowires (NWs) with a high Sb content have potential in the fabrication of advanced silicon-based optoelectronics such as infrared photondetectors/emitters and highly sensitive phototransistors, as well as in the generation of renewable electricity. However, producing optically efficient InAsSb NWs with a high Sb content remains a challenge, and optical emission is limited to 4.0 μm due to the quality of the nanowires. Here, we report, for the first time, the success of high-quality and optically efficient InAsSb NWs enabling silicon-based optoelectronics operating in entirely mid-wavelength infrared. Pure zinc-blende InAsSb NWs were realized with efficient photoluminescence emission. We obtained room-temperature photoluminescence emission in InAs NWs and successfully extended the emission wavelength in InAsSb NWs to 5.1 μm. The realization of this optically efficient InAsSb NW material paves the way to realizing next-generation devices, combining advances in III-V semiconductors and silicon.

High-throughput linear optical stretcher for mechanical characterization of blood cells.

PubMed

Roth, Kevin B; Neeves, Keith B; Squier, Jeff; Marr, David W M

2016-04-01

This study describes a linear optical stretcher as a high-throughput mechanical property cytometer. Custom, inexpensive, and scalable optics image a linear diode bar source into a microfluidic channel, where cells are hydrodynamically focused into the optical stretcher. Upon entering the stretching region, antipodal optical forces generated by the refraction of tightly focused laser light at the cell membrane deform each cell in flow. Each cell relaxes as it flows out of the trap and is compared to the stretched state to determine deformation. The deformation response of untreated red blood cells and neutrophils were compared to chemically treated cells. Statistically significant differences were observed between normal, diamide-treated, and glutaraldehyde-treated red blood cells, as well as between normal and cytochalasin D-treated neutrophils. Based on the behavior of the pure, untreated populations of red cells and neutrophils, a mixed population of these cells was tested and the discrete populations were identified by deformability. © 2015 International Society for Advancement of Cytometry. © 2015 International Society for Advancement of Cytometry.

The advanced LIGO input optics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mueller, Chris L., E-mail: cmueller@phys.ufl.edu; Arain, Muzammil A.; Ciani, Giacomo

The advanced LIGO gravitational wave detectors are nearing their design sensitivity and should begin taking meaningful astrophysical data in the fall of 2015. These resonant optical interferometers will have unprecedented sensitivity to the strains caused by passing gravitational waves. The input optics play a significant part in allowing these devices to reach such sensitivities. Residing between the pre-stabilized laser and the main interferometer, the input optics subsystem is tasked with preparing the laser beam for interferometry at the sub-attometer level while operating at continuous wave input power levels ranging from 100 mW to 150 W. These extreme operating conditions requiredmore » every major component to be custom designed. These designs draw heavily on the experience and understanding gained during the operation of Initial LIGO and Enhanced LIGO. In this article, we report on how the components of the input optics were designed to meet their stringent requirements and present measurements showing how well they have lived up to their design.« less

Point-of-care and point-of-procedure optical imaging technologies for primary care and global health.

PubMed

Boppart, Stephen A; Richards-Kortum, Rebecca

2014-09-10

Leveraging advances in consumer electronics and wireless telecommunications, low-cost, portable optical imaging devices have the potential to improve screening and detection of disease at the point of care in primary health care settings in both low- and high-resource countries. Similarly, real-time optical imaging technologies can improve diagnosis and treatment at the point of procedure by circumventing the need for biopsy and analysis by expert pathologists, who are scarce in developing countries. Although many optical imaging technologies have been translated from bench to bedside, industry support is needed to commercialize and broadly disseminate these from the patient level to the population level to transform the standard of care. This review provides an overview of promising optical imaging technologies, the infrastructure needed to integrate them into widespread clinical use, and the challenges that must be addressed to harness the potential of these technologies to improve health care systems around the world. Copyright © 2014, American Association for the Advancement of Science.

Advanced Learning Theories Applied to Leadership Development

DTIC Science & Technology

2006-11-01

Theory . We combined the cognitive , experiential and motivational components of advanced learning theories to develop a training application...Center for Army Leadership Technical Report 2006-2 Advanced Learning Theories Applied to Leadership Development Christina Curnow...2006 5a. CONTRACT NUMBER W91QF4-05-F-0026 5b. GRANT NUMBER 4. TITLE AND SUBTITLE Advanced Learning Theories Applied to Leadership Development 5c

X-Ray Spectroscopy of Optically Bright Planets using the Chandra Observatory

NASA Technical Reports Server (NTRS)

Ford, P. G.; Elsner, R. F.

2005-01-01

Since its launch in July 1999, Chandra's Advanced CCD Imaging Spectrometer (ACIS) has observed several planets (Venus, Mars, Jupiter and Saturn) and 6 comets. At 0.5 arc-second spatial resolution, ACIS detects individual x-ray photons with good quantum efficiency (25% at 0.6 KeV) and energy resolution (20% FWHM at 0.6 KeV). However, the ACIS CCDs are also sensitive to optical and near-infrared light, which is absorbed by optical blocking filters (OBFs) that eliminate optical contamination from all but the brightest extended sources, e.g., planets. .Jupiter at opposition subseconds approx.45 arc-seconds (90 CCD pixels.) Since Chandra is incapable of tracking a moving target, the planet takes 10 - 20 kiloseconds to move across the most sensitive ACIS CCD, after which the observatory must be re-pointed. Meanwhile, the OBF covering that CCD adds an opt,ical signal equivalent to approx.110 eV to each pixel that lies within thc outline of the Jovian disk. This has three consequences: (1) the observatory must be pointed away from Jupiter while CCD bias maps are constructed; (2) most x-rays from within the optical image will be misidentified as charged-particle background and ignored; and (3) those x-rays that are reported will bc assigned anomalously high energies. The same also applies to thc other planets, but is less serious since they are either dimmer at optical wavelengths, or they show less apparent motion across the sky, permitting reduced CCD exposure times: the optical contamination from Saturn acids approx.15 eV per pixel, and from Mars and Venus approx.31 eV. After analyzing a series of short .Jupiter observations in December 2000, ACIS parameters were optimized for the February 2003 opposition. CCD bias maps were constructed while Chandra pointed away from Jupiter, and the subsequent observations employed on-board software to ignore any pixel that contained less charge than that expected from optical leakage. In addition, ACIS was commanded to report 5 x 5 arrays of pixel values surrounding each x-ray event, and the outlying values were employed during ground processing to correct for the optical contamination.

Fiber optic control system integration

NASA Technical Reports Server (NTRS)

Poppel, G. L.; Glasheen, W. M.; Russell, J. C.

1987-01-01

A total fiber optic, integrated propulsion/flight control system concept for advanced fighter aircraft is presented. Fiber optic technology pertaining to this system is identified and evaluated for application readiness. A fiber optic sensor vendor survey was completed, and the results are reported. The advantages of centralized/direct architecture are reviewed, and the concept of the protocol branch is explained. Preliminary protocol branch selections are made based on the F-18/F404 application. Concepts for new optical tools are described. Development plans for the optical technology and the described system are included.

Applicability of geometrical optics to in-plane liquid-crystal configurations.

PubMed

Sluijter, M; Xu, M; Urbach, H P; de Boer, D K G

2010-02-15

We study the applicability of geometrical optics to inhomogeneous dielectric nongyrotropic optically anisotropic media typically found in in-plane liquid-crystal configurations with refractive indices n(o)=1.5 and n(e)=1.7. To this end, we compare the results of advanced ray- and wave-optics simulations of the propagation of an incident plane wave to a special anisotropic configuration. Based on the results, we conclude that for a good agreement between ray and wave optics, a maximum change in optical properties should occur over a distance of at least 20 wavelengths.

Optical methods for the optimization of system SWaP-C using aspheric components and advanced optical polymers

NASA Astrophysics Data System (ADS)

Zelazny, Amy; Benson, Robert; Deegan, John; Walsh, Ken; Schmidt, W. David; Howe, Russell

2013-06-01

We describe the benefits to camera system SWaP-C associated with the use of aspheric molded glasses and optical polymers in the design and manufacture of optical components and elements. Both camera objectives and display eyepieces, typical for night vision man-portable EO/IR systems, are explored. We discuss optical trade-offs, system performance, and cost reductions associated with this approach in both visible and non-visible wavebands, specifically NIR and LWIR. Example optical models are presented, studied, and traded using this approach.

Progress in Evaluating Quantitative Optical Gas Imaging

EPA Science Inventory

Development of advanced fugitive emission detection and assessment technologies that facilitate cost effective leak and malfunction mitigation strategies is an ongoing goal shared by industry, regulators, and environmental groups. Optical gas imaging (OGI) represents an importan...

Report to Congress on the Activities of the DoD Office of Technology Transition

DTIC Science & Technology

2001-02-01

known as Magnetorheological Finishing (MRF), that provides significant cost savings in the manufacture of precision optical surfaces. Compared to...The programs included: - The Army’s Advanced Optics Manufacturing program developed a multi- axis, computer-controlled optical finishing technology...percent. The MRF finishing machine is commercially available, and has received industry-wide acclaim, winning two of the optical industry’s most

[INVITED] Recent advances in surface plasmon resonance based fiber optic chemical and biosensors utilizing bulk and nanostructures

NASA Astrophysics Data System (ADS)

Gupta, Banshi D.; Kant, Ravi

2018-05-01

Surface plasmon resonance has established itself as an immensely acclaimed and influential optical sensing tool with quintessential applications in life sciences, environmental monitoring, clinical diagnostics, pharmaceutical developments and ensuring food safety. The implementation of sensing principle of surface plasmon resonance employing an optical fiber as a substrate has concomitantly resulted in the evolution of fiber optic surface plasmon resonance as an exceptionally lucrative scaffold for chemical and biosensing applications. This perspective article outlines the contemporary studies on fiber optic sensors founded on the sensing architecture of propagating as well as localized surface plasmon resonance. An in-depth review of the prevalent analytical and surface chemical tactics involved in configuring the sensing layer over an optical fiber for the detection of various chemical and biological entities is presented. The involvement of nanomaterials as a strategic approach to enhance the sensor sensitivity is furnished concurrently providing an insight into the diverse geometrical blueprints for designing fiber optic sensing probes. Representative examples from the literature are discussed to appreciate the latest advancements in this potentially valuable research avenue. The article concludes by identifying some of the key challenges and exploring the opportunities for expanding the scope and impact of surface plasmon resonance based fiber optic sensors.

PREFACE: Ultrafast biophotonics Ultrafast biophotonics

NASA Astrophysics Data System (ADS)

Gu, Min; Reid, Derryck; Ben-Yakar, Adela

2010-08-01

The use of light to explore biology can be traced to the first observations of tissue made with early microscopes in the mid-seventeenth century, and has today evolved into the discipline which we now know as biophotonics. This field encompasses a diverse range of activities, each of which shares the common theme of exploiting the interaction of light with biological material. With the rapid advancement of ultrafast optical technologies over the last few decades, ultrafast lasers have increasingly found applications in biophotonics, to the extent that the distinctive new field of ultrafast biophotonics has now emerged, where robust turnkey ultrafast laser systems are facilitating cutting-edge studies in the life sciences to take place in everyday laboratories. The broad spectral bandwidths, precision timing resolution, low coherence and high peak powers of ultrafast optical pulses provide unique opportunities for imaging and manipulating biological systems. Time-resolved studies of bio-molecular dynamics exploit the short pulse durations from such lasers, while other applications such as optical coherence tomography benefit from the broad optical bandwidths possible by using super-continuum generation and additionally allowing for high speed imaging with speeds as high as 47 000 scans per second. Continuing progress in laser-system technology is accelerating the adoption of ultrafast techniques across the life sciences, both in research laboratories and in clinical applications, such as laser-assisted in situ keratomileusis (LASIK) eye surgery. Revolutionizing the field of optical microscopy, two-photon excitation fluorescence (TPEF) microscopy has enabled higher spatial resolution with improved depth penetration into biological specimens. Advantages of this nonlinear optical process include: reduced photo-interactions, allowing for extensive imaging time periods; simultaneously exciting multiple fluorescent molecules with only one excitation wavelength; and reduced chromatic aberration effects. These extensive advantages have led to further exploration of nonlinear processes including second-harmonic generation (SHG) microscopy and third-harmonic generation (THG) microscopy. Second-harmonic generation has provided biologists with an extremely powerful tool for generating contrast in biological imaging, with the additional benefit of non-invasive three-dimensional imaging. The recent popularity of THG microscopy is largely due to the fact that three-dimensional imaging is achievable without the need for any labels, but rather relying on the intrinsic properties of the biological specimen itself. This optical nonlinear technique has attracted much attention recently from the biological community due to its non-invasive capabilities. Users of ultrafast lasers in the biological and medical fields are becoming a fast-growing community, employing pulse-shaping microscopy, resolution-enhancing microscopy techniques, linear and nonlinear micro-spectroscopy, functional deep-tissue imaging, optical coherence tomography, nonlinear fluorescence microscopy, molecular imaging and control, harmonic microscopy and femtosecond lifetime imaging, for cutting-edge research concerning the interaction of light with biological dynamics. The adaptability of ultrafast lasers to interact with a large array of materials through nonlinear excitation has enabled precise control of laser fluence allowing for highly localized material interactions, permitting micro-structured fabricated surfaces. The resultant multi-dimensional fabricated micro-structures are capable of replicating and/or manipulating microenvironments for controlled cell biology. In this special issue of Journal of Optics readers have a chance to view a collection of new contributions to the growing research field of ultrafast biophotonics. They are presented with recent advances in ultrafast technology applied to biological and medical investigations, where topics include advances in the visualization and identification of photo-reaction dynamics of biological functions under relevant physiological conditions, theoretically proposed imaging designs for obtaining super-resolved optical sectioned images in single exposures and fabricated micro-structured surfaces for biological micro-environments. We hope the collection will stimulate innovative new research in this growing field by showcasing new techniques for the visualization and manipulation of complex biological systems using linear and and nonlinear optical processes. Professor Min Gu would like to acknowledge Dr Betty Kouskousis for her contribution and support towards this editorial.

Nonlinear and non-Hermitian optical systems applied to the development of filters and optical sensors

NASA Astrophysics Data System (ADS)

Amaro de Faria Júnior, A. C.

2015-09-01

In this work we present a method of investigation of nonlinear optical beams generated from non-Hermitian optical systems1 . This method can be applied in the development of optical filters and optical sensors to process, analyze and choose the passband of the propagation modes of an optical pulse from an non-Hermitian optical system. Non-Hermitian optical systems can be used to develop optical fiber sensors that suppress certain propagation modes of optical pulses that eventually behave as quantum noise. Such systems are described by the Nonlinear Schrödinger-like Equation with Parity-Time (PT) Symmetric Optical Potentials. There are optical fiber sensors that due to high laser intensity and frequency can produce quantum noise, such as Raman and Brillouin scattering. However, the optical fiber, for example, can be designed so that its geometry suppress certain propagation modes of the beam. We apply some results of non- Hermitian optical systems with PT symmetry to simulate optical lattice by a appropriate potential function, which among other applications, can naturally suppress certain propagation modes of an optical beam propagating through a waveguide. In other words, the optical system is modeled by a potential function in the Nonlinear Schrödinger-like Equation that one relates with the geometric aspects of the wave guides and with the optical beam interacting with the waveguide material. The paper is organized as follows: sections 1 and 2 present a brief description about nonlinear optical systems and non-Hermitian optical systems with PT symmetry. Section 3 presents a description of the dynamics of nonlinear optical pulses propagating through optical networks described by a optical potential non-Hermitian. Sections 4 and 5 present a general description of this non-Hermitian optical systems and how to get them from a more general model. Section 6 presents some conclusions and comment and the final section presents the references. Begin the abstract two lines below author names and addresses.

Multichannel demultiplexer/demodulator technologies for future satellite communication systems

NASA Technical Reports Server (NTRS)

Ivancic, William D.; Budinger, James M.; Staples, Edward J.; Abramovitz, Irwin; Courtois, Hector A.

1992-01-01

NASA-Lewis' Space Electronics Div. supports ongoing research in advanced satellite communication architectures, onboard processing, and technology development. Recent studies indicate that meshed VSAT (very small aperture terminal) satellite communication networks using FDMA (frequency division multiple access) uplinks and TDMA (time division multiplexed) downlinks are required to meet future communication needs. One of the critical advancements in such a satellite communication network is the multichannel demultiplexer/demodulator (MCDD). The progress is described which was made in MCDD development using either acousto-optical, optical, or digital technologies.

Teaching of optics and photonics in a college astronomy course

NASA Astrophysics Data System (ADS)

Tremberger, George, Jr.; Flamholz, Alex; Marchese, Paul J.; Lieberman, David H.; Cheung, Tak D.

2004-10-01

Astronomy is among the most popular courses that students select to fulfill their college science requirement at Queensborough Community College, New York City. Recent advances in photonics now enable us to observe celestial objects from extrasolar planets to ultra deep space galaxies that are 13 billion light years away. These results are regularly reported in the popular press such as the New York Times and "Sky & Telescope" magazine. We upgraded our astronomy course to keep pace with these advances in optics and photonics. The laboratory hands-on exercises include observations in our observatory using a telescope with digital camera and CCD, spectrum analysis with grating, Java photonics simulation delivered over the Internet, and the use of virtual instruments in optics and photonics written with Labview. Advanced techniques such as interferometry are also included as demonstrations in the laboratory. The scientific principles were demonstrated to them to promote learning by inquiry. As a result of these teaching designs, the students gain a clearer understanding of the optics and photonics basis of the astronomical instrumentation reported in popular articles. The preliminary assessment was encouraging as measured by the number of questions received and the amount of popular press materials that the students brought to the classroom.

Photonomics: automation approaches yield economic aikido for photonics device manufacture

NASA Astrophysics Data System (ADS)

Jordan, Scott

2002-09-01

In the glory days of photonics, with exponentiating demand for photonics devices came exponentiating competition, with new ventures commencing deliveries seemingly weekly. Suddenly the industry was faced with a commodity marketplace well before a commodity cost structure was in place. Economic issues like cost, scalability, yield-call it all "Photonomics" -now drive the industry. Automation and throughput-optimization are obvious answers, but until now, suitable modular tools had not been introduced. Available solutions were barely compatible with typical transverse alignment tolerances and could not automate angular alignments of collimated devices and arrays. And settling physics served as the insoluble bottleneck to throughput and resolution advancement in packaging, characterization and fabrication processes. The industry has addressed these needs in several ways, ranging from special configurations of catalog motion devices to integrated microrobots based on a novel mini-hexapod configuration. This intriguing approach allows tip/tilt alignments to be automated about any point in space, such as a beam waist, a focal point, the cleaved face of a fiber, or the optical axis of a waveguide- ideal for MEMS packaging automation and array alignment. Meanwhile, patented new low-cost settling-enhancement technology has been applied in applications ranging from air-bearing long-travel stages to subnanometer-resolution piezo positioners to advance resolution and process cycle-times in sensitive applications such as optical coupling characterization and fiber Bragg grating generation. Background, examples and metrics are discussed, providing an up-to-date industry overview of available solutions.

Fiber-Optic/Photoelastic Flow Sensors

NASA Technical Reports Server (NTRS)

Wesson, Laurence N.; Cabato, Nellie L.; Brooks, Edward F.

1995-01-01

Simple, rugged, lightweight transducers detect periodic vortices. Fiber-optic-coupled transducers developed to measure flows over wide dynamic ranges and over wide temperature ranges in severe environments. Used to measure flows of fuel in advanced aircraft engines. Feasibility of sensors demonstrated in tests of prototype sensor in water flowing at various temperatures and speeds. Particularly attractive for aircraft applications because optical fibers compact and make possible transmission of sensor signals at high rates with immunity from electromagnetic interference at suboptical frequencies. Sensors utilize optical-to-optical conversion via photoelastic effect.

Optical trapping

PubMed Central

Neuman, Keir C.; Block, Steven M.

2006-01-01

Since their invention just over 20 years ago, optical traps have emerged as a powerful tool with broad-reaching applications in biology and physics. Capabilities have evolved from simple manipulation to the application of calibrated forces on—and the measurement of nanometer-level displacements of—optically trapped objects. We review progress in the development of optical trapping apparatus, including instrument design considerations, position detection schemes and calibration techniques, with an emphasis on recent advances. We conclude with a brief summary of innovative optical trapping configurations and applications. PMID:16878180

Molecular Imaging: Current Status and Emerging Strategies

PubMed Central

Pysz, Marybeth A.; Gambhir, Sanjiv S.; Willmann, Jürgen K.

2011-01-01

In vivo molecular imaging has a great potential to impact medicine by detecting diseases in early stages (screening), identifying extent of disease, selecting disease- and patient-specific therapeutic treatment (personalized medicine), applying a directed or targeted therapy, and measuring molecular-specific effects of treatment. Current clinical molecular imaging approaches primarily use PET- or SPECT-based techniques. In ongoing preclinical research novel molecular targets of different diseases are identified and, sophisticated and multifunctional contrast agents for imaging these molecular targets are developed along with new technologies and instrumentation for multimodality molecular imaging. Contrast-enhanced molecular ultrasound with molecularly-targeted contrast microbubbles is explored as a clinically translatable molecular imaging strategy for screening, diagnosing, and monitoring diseases at the molecular level. Optical imaging with fluorescent molecular probes and ultrasound imaging with molecularly-targeted microbubbles are attractive strategies since they provide real-time imaging, are relatively inexpensive, produce images with high spatial resolution, and do not involve exposure to ionizing irradiation. Raman spectroscopy/microscopy has emerged as a molecular optical imaging strategy for ultrasensitive detection of multiple biomolecules/biochemicals with both in vivo and ex vivo versatility. Photoacoustic imaging is a hybrid of optical and ultrasound modalities involving optically-excitable molecularly-targeted contrast agents and quantitative detection of resulting oscillatory contrast agent movement with ultrasound. Current preclinical findings and advances in instrumentation such as endoscopes and microcatheters suggest that these molecular imaging modalities have numerous clinical applications and will be translated into clinical use in the near future. PMID:20541650

An underwater optical wireless communication network

NASA Astrophysics Data System (ADS)

Arnon, Shlomi

2009-08-01

The growing need for underwater observation and sub-sea monitoring systems has stimulated considerable interest in advancing the enabling technologies of underwater wireless communication and underwater sensor networks. This communication technology is expected to play an important role in investigating climate change, in monitoring biological, bio-geochemical, evolutionary and ecological changes in the sea, ocean and lake environments and in helping to control and maintain oil production facilities and harbors using unmanned underwater vehicles (UUVs), submarines, ships, buoys, and divers. However, the present technology of underwater acoustic communication cannot provide the high data rate required to investigate and monitor these environments and facilities. Optical wireless communication has been proposed as the best alternative to meet this challenge. We present models of three kinds of optical wireless communication links a) a line-of-sight link, b) a modulating retro-reflector link and c) a reflective link, all of which can provide the required data rate. We analyze the link performance based on these models. From the analysis, it is clear that as the water absorption increases, the communication performance decreases dramatically for the three link types. However, by using the scattered lighted it was possible to mitigate this decrease in some cases. We conclude from the analysis that a high data rate underwater optical wireless network is a feasible solution for emerging applications such as UUV to UUV links and networks of sensors, and extended ranges in these applications could be achieved by applying a multi-hop concept.

Underwater optical wireless communication network

NASA Astrophysics Data System (ADS)

Arnon, Shlomi

2010-01-01

The growing need for underwater observation and subsea monitoring systems has stimulated considerable interest in advancing the enabling technologies of underwater wireless communication and underwater sensor networks. This communication technology is expected to play an important role in investigating climate change, in monitoring biological, biogeochemical, evolutionary, and ecological changes in the sea, ocean, and lake environments, and in helping to control and maintain oil production facilities and harbors using unmanned underwater vehicles (UUVs), submarines, ships, buoys, and divers. However, the present technology of underwater acoustic communication cannot provide the high data rate required to investigate and monitor these environments and facilities. Optical wireless communication has been proposed as the best alternative to meet this challenge. Models are presented for three kinds of optical wireless communication links: (a) a line-of-sight link, (b) a modulating retroreflector link, and (c) a reflective link, all of which can provide the required data rate. We analyze the link performance based on these models. From the analysis, it is clear that as the water absorption increases, the communication performance decreases dramatically for the three link types. However, by using the scattered light it was possible to mitigate this decrease in some cases. It is concluded from the analysis that a high-data-rate underwater optical wireless network is a feasible solution for emerging applications such as UUV-to-UUV links and networks of sensors, and extended ranges in these applications could be achieved by applying a multi-hop concept.

Advanced Telescopes and Observatories Capability Roadmap Presentation to the NRC

NASA Technical Reports Server (NTRS)

2005-01-01

This viewgraph presentation provides an overview of the NASA Advanced Planning and Integration Office (APIO) roadmap for developing technological capabilities for telescopes and observatories in the following areas: Optics; Wavefront Sensing and Control and Interferometry; Distributed and Advanced Spacecraft; Large Precision Structures; Cryogenic and Thermal Control Systems; Infrastructure.

Optics & Materials Science & Technology (OMST) Organization at LLNL

ScienceCinema

Suratwala,; Tayyab,; Nguyen, Hoang; Bude, Jeff; Dylla-Spears, Rebecca

2018-06-13

The Optics and Materials Science & Technology (OMST) organization at Lawrence Livermore National Laboratory (LLNL) supplies optics, recycles optics, and performs the materials science and technology to advance optics and optical materials for high-power and high-energy lasers for a variety of missions. The organization is a core capability at LLNL. We have a strong partnership with many optical fabricators, universities and national laboratories to accomplish our goals. The organization has a long history of performing fundamental optical materials science, developing them into useful technologies, and transferring them into production both on-site and off-site. We are successfully continuing this same strategy today.

Optics & Materials Science & Technology (OMST) Organization at LLNL

DOE Office of Scientific and Technical Information (OSTI.GOV)

Suratwala,; Tayyab,; Nguyen, Hoang

The Optics and Materials Science & Technology (OMST) organization at Lawrence Livermore National Laboratory (LLNL) supplies optics, recycles optics, and performs the materials science and technology to advance optics and optical materials for high-power and high-energy lasers for a variety of missions. The organization is a core capability at LLNL. We have a strong partnership with many optical fabricators, universities and national laboratories to accomplish our goals. The organization has a long history of performing fundamental optical materials science, developing them into useful technologies, and transferring them into production both on-site and off-site. We are successfully continuing this same strategymore » today.« less