Dual-polarized light-field imaging micro-system via a liquid-crystal microlens array for direct three-dimensional observation.

PubMed

Xin, Zhaowei; Wei, Dong; Xie, Xingwang; Chen, Mingce; Zhang, Xinyu; Liao, Jing; Wang, Haiwei; Xie, Changsheng

2018-02-19

Light-field imaging is a crucial and straightforward way of measuring and analyzing surrounding light worlds. In this paper, a dual-polarized light-field imaging micro-system based on a twisted nematic liquid-crystal microlens array (TN-LCMLA) for direct three-dimensional (3D) observation is fabricated and demonstrated. The prototyped camera has been constructed by integrating a TN-LCMLA with a common CMOS sensor array. By switching the working state of the TN-LCMLA, two orthogonally polarized light-field images can be remapped through the functioned imaging sensors. The imaging micro-system in conjunction with the electric-optical microstructure can be used to perform polarization and light-field imaging, simultaneously. Compared with conventional plenoptic cameras using liquid-crystal microlens array, the polarization-independent light-field images with a high image quality can be obtained in the arbitrary polarization state selected. We experimentally demonstrate characters including a relatively wide operation range in the manipulation of incident beams and the multiple imaging modes, such as conventional two-dimensional imaging, light-field imaging, and polarization imaging. Considering the obvious features of the TN-LCMLA, such as very low power consumption, providing multiple imaging modes mentioned, simple and low-cost manufacturing, the imaging micro-system integrated with this kind of liquid-crystal microstructure driven electrically presents the potential capability of directly observing a 3D object in typical scattering media.

Development of a novel non-contact inspection technique to detect micro cracks under the surface of a glass substrate by thermal stress-induced light scattering method

NASA Astrophysics Data System (ADS)

Sakata, Yoshitaro; Terasaki, Nao; Nonaka, Kazuhiro

2017-05-01

Fine polishing techniques, such as a chemical mechanical polishing treatment, are important techniques in glass substrate manufacturing. However, these techniques may cause micro cracks under the surface of glass substrates because they used mechanical friction. A stress-induced light scattering method (SILSM), which was combined with light scattering method and mechanical stress effects, was proposed for inspecting surfaces to detect polishing-induced micro cracks. However, in the conventional SILSM, samples need to be loaded with physical contact, and the loading point is invisible in transparent materials. Here, we introduced a novel non-contact SILSM using a heating device. A glass substrate was heated first, and then the light scattering intensity of micro cracks was detected by a cooled charge-couple device camera during the natural cooling process. Results clearly showed during the decreasing surface temperature of a glass substrate, appropriate thermal stress is generated for detecting micro cracks by using the SILSM and light scattering intensity from micro cracks changes. We confirmed that non-contact thermal SILSM (T-SILSM) can detect micro cracks under the surface of transparent materials.

Micro Solar Cells with Concentration and Light Trapping Optics

NASA Astrophysics Data System (ADS)

Li, Lanfang; Breuckner, Eric; Corcoran, Christopher; Yao, Yuan; Xu, Lu; Nuzzo, Ralph

2013-03-01

Compared with conventional bulk plate semiconductor solar cells, micro solar cells provide opportunity for novel design geometry and provide test bed for light trapping at the device level as well as module level. Surface recombination, however, will have to be addressed properly as the much increased surface area due to the reduced dimension is more prominent in these devices than conventional solar cells. In this poster, we present experimental demonstration of silicon micro solar cells with concentration and light trapping optics. Silicon micro solar cell with optimized surface passivation and doping profile that exhibit high efficiency is demonstrated. Effective incorporation of high quantum yield fluorescent centers in the polymer matrix into which micro solar cell was encapsulated was investigated for luminescent solar concentration application. Micro-cell on a semi-transparent, nanopatterned reflector formed by soft-imprint lithography was investigated for near field effect related solar conversion performance enhancement. This work is supported by the DOE `Light-Material Interactions in Energy Conversion' Energy Frontier Research Center under grant DE-SC0001293

3D model of filler melting with micro-beam plasma arc based on additive manufacturing technology

NASA Astrophysics Data System (ADS)

Chen, Weilin; Yang, Tao; Yang, Ruixin

2017-07-01

Additive manufacturing technology is a systematic process based on discrete-accumulation principle, which is derived by the dimension of parts. Aiming at the dimension mathematical model and slicing problems in additive manufacturing process, the constitutive relations between micro-beam plasma welding parameters and the dimension of part were investigated. The slicing algorithm and slicing were also studied based on the dimension characteristics. By using the direct slicing algorithm according to the geometric characteristics of model, a hollow thin-wall spherical part was fabricated by 3D additive manufacturing technology using micro-beam plasma.

Micro spectrometer for parallel light and method of use

NASA Technical Reports Server (NTRS)

Park, Yeonjoon (Inventor); Choi, Sang H. (Inventor); King, Glen C. (Inventor); Elliott, James R. (Inventor)

2011-01-01

A spectrometer system includes an optical assembly for collimating light, a micro-ring grating assembly having a plurality of coaxially-aligned ring gratings, an aperture device defining an aperture circumscribing a target focal point, and a photon detector. An electro-optical layer of the grating assembly may be electrically connected to an energy supply to change the refractive index of the electro-optical layer. Alternately, the gratings may be electrically connected to the energy supply and energized, e.g., with alternating voltages, to change the refractive index. A data recorder may record the predetermined spectral characteristic. A method of detecting a spectral characteristic of a predetermined wavelength of source light includes generating collimated light using an optical assembly, directing the collimated light onto the micro-ring grating assembly, and selectively energizing the micro-ring grating assembly to diffract the predetermined wavelength onto the target focal point, and detecting the spectral characteristic using a photon detector.

Determination of Strain Rate Sensitivity of Micro-struts Manufactured Using the Selective Laser Melting Method

NASA Astrophysics Data System (ADS)

Gümrük, Recep; Mines, R. A. W.; Karadeniz, Sami

2018-03-01

Micro-lattice structures manufactured using the selective laser melting (SLM) process provides the opportunity to realize optimal cellular materials for impact energy absorption. In this paper, strain rate-dependent material properties are measured for stainless steel 316L SLM micro-lattice struts in the strain rate range of 10-3 to 6000 s-1. At high strain rates, a novel version of the split Hopkinson Bar has been developed. Strain rate-dependent materials data have been used in Cowper-Symonds material model, and the scope and limit of this model in the context of SLM struts have been discussed. Strain rate material data and the Cowper-Symonds model have been applied to the finite element analysis of a micro-lattice block subjected to drop weight impact loading. The model output has been compared to experimental results, and it has been shown that the increase in crush stress due to impact loading is mainly the result of strain rate material behavior. Hence, a systematic methodology has been developed to investigate the impact energy absorption of a micro-lattice structure manufactured using additive layer manufacture (SLM). This methodology can be extended to other micro-lattice materials and configurations, and to other impact conditions.

Wafer-scale micro-optics fabrication

NASA Astrophysics Data System (ADS)

Voelkel, Reinhard

2012-07-01

Micro-optics is an indispensable key enabling technology for many products and applications today. Probably the most prestigious examples are the diffractive light shaping elements used in high-end DUV lithography steppers. Highly-efficient refractive and diffractive micro-optical elements are used for precise beam and pupil shaping. Micro-optics had a major impact on the reduction of aberrations and diffraction effects in projection lithography, allowing a resolution enhancement from 250 nm to 45 nm within the past decade. Micro-optics also plays a decisive role in medical devices (endoscopes, ophthalmology), in all laser-based devices and fiber communication networks, bringing high-speed internet to our homes. Even our modern smart phones contain a variety of micro-optical elements. For example, LED flash light shaping elements, the secondary camera, ambient light and proximity sensors. Wherever light is involved, micro-optics offers the chance to further miniaturize a device, to improve its performance, or to reduce manufacturing and packaging costs. Wafer-scale micro-optics fabrication is based on technology established by the semiconductor industry. Thousands of components are fabricated in parallel on a wafer. This review paper recapitulates major steps and inventions in wafer-scale micro-optics technology. The state-of-the-art of fabrication, testing and packaging technology is summarized.

Enhanced light extraction efficiency of micro-ring array AlGaN deep ultraviolet light-emitting diodes

NASA Astrophysics Data System (ADS)

Bekele Fayisa, Gabisa; Lee, Jong Won; Kim, Jungsub; Kim, Yong-Il; Park, Youngsoo; Kim, Jong Kyu

2017-09-01

An effective approach to overcome inherently poor light extraction efficiency of AlGaN-based deep ultraviolet (DUV) light-emitting diodes (LEDs) is presented. We demonstrated the 5 × 5 array micro-ring DUV LED having an inclined sidewall at the outer perimeter and a p-GaN-removed inner circle of the micro-ring, together with MgF2/Al omnidirectional reflectors. The micro-ring array DUV LED shows remarkably higher light output power by 70% than the reference, consistent with the calculated result, as well as comparable turn-on and operational voltages, which are attributed to the effective extraction of strong transverse-magnetic polarized anisotropic emission and the reduction of the absorption loss by the p-GaN contact layer, simultaneously.

Fabrication, characterization and applications of flexible vertical InGaN micro-light emitting diode arrays.

PubMed

Tian, Pengfei; McKendry, Jonathan J D; Gu, Erdan; Chen, Zhizhong; Sun, Yongjian; Zhang, Guoyi; Dawson, Martin D; Liu, Ran

2016-01-11

Flexible vertical InGaN micro-light emitting diode (micro-LED) arrays have been fabricated and characterized for potential applications in flexible micro-displays and visible light communication. The LED epitaxial layers were transferred from initial sapphire substrates to flexible AuSn substrates by metal bonding and laser lift off techniques. The current versus voltage characteristics of flexible micro-LEDs degraded after bending the devices, but the electroluminescence spectra show little shift even under a very small bending radius 3 mm. The high thermal conductivity of flexible metal substrates enables high thermal saturation current density and high light output power of the flexible micro-LEDs, benefiting the potential applications in flexible high-brightness micro-displays and high-speed visible light communication. We have achieved ~40 MHz modulation bandwidth and 120 Mbit/s data transmission speed for a typical flexible micro-LED.

Protection of therapeutic antibodies from visible light induced degradation: Use safe light in manufacturing and storage.

PubMed

Du, Cheng; Barnett, Gregory; Borwankar, Ameya; Lewandowski, Angela; Singh, Nripen; Ghose, Sanchayita; Borys, Michael; Li, Zheng Jian

2018-06-01

As macromolecules, biologics are susceptible to light exposure, which induces oxidation of multiple amino acid residues including tryptophan, tyrosine, phenylalanine, cysteine and methionine. Pertaining to safety, efficacy and potency, light-induced oxidation of biologics has been widely studied and necessary precautions need to be taken during biologics manufacturing process, drug substance and products handling and storage. Proteins will degrade to varying extents depending on the protein properties, degradation pathways, formulation compositions and type of light source. In addition to UV light, which has been widely known to degrade proteins, visible light from indoor fluorescent lighting also can mediate protein degradation. In this report, we examine and identify wavelengths in the visual spectrum (400-700 nm) that can cause monoclonal antibody and histidine buffer degradation. Installation of safe lights which exclude the identified damaging wavelengths from visible spectra in manufacturing and storage areas can provide a balance between lighting requirement for human operators and their safety and conservation of product quality. Copyright © 2018 Elsevier B.V. All rights reserved.

Creation of a U.S. Phosphorescent OLED Lighting Panel Manufacturing Facility

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

Hack, Michael

Universal Display Corporation (UDC) has pioneered high efficacy phosphorescent OLED (PHOLED™) technology to enable the realization of an exciting new form of high quality, energy saving solid-date lighting. In laboratory test devices, we have demonstrated greater than 100 lm/W conversion efficacy. In this program, Universal Display will demonstrate the scalability of its proprietary UniversalPHOLED technology and materials for the manufacture of white OLED lighting panels that meet commercial lighting targets. Moser Baer Technologies will design and build a U.S.- based pilot facility. The objective of this project is to establish a pilot phosphorescent OLED (PHOLED) manufacturing line in the U.S.more » Our goal is that at the end of the project, prototype lighting panels could be provided to U.S. luminaire manufacturers for incorporation into products to facilitate the testing of design concepts and to gauge customer acceptance, so as to facilitate the growth of the embryonic U.S. OLED lighting industry. In addition, the team will provide a cost of ownership analysis to quantify production costs including OLED performance metrics which relate to OLED cost such as yield, materials usage, cycle time, substrate area, and capital depreciation. This project was part of a new DOE initiative designed to help establish and maintain U.S. leadership in this program will support key DOE objectives by showing a path to meet Department of Energy Solid-State Lighting Manufacturing Roadmap cost targets, as well as meeting its efficiency targets by demonstrating the energy saving potential of our technology through the realization of greater than 76 lm/W OLED lighting panels by 2012.« less

Study of Selecting on Light Source Used for Micro-algae Cultivation in Space

NASA Astrophysics Data System (ADS)

Ai, Weidang; Ai, Weidang; Guo, Shuang-Sheng; Gao, Feng; Tang, Yong-Kang; Qin, Li-Feng

To select suitable light source for micro-algae cultivation in future space station, the selected Spirulina plastensis(No.7) were cultured under different lightening qualities, including six light sources that were made up of different combinations of red and blue light-emitting diode(LED). The growth, photosynthetic efficiency and nutrition quality of the Spirulina, were analyzed. From the experiments, the red light may promote the cumulation of biomass of the Spirulina, and the cumulating rate was the highest under all red light source, but the syntheses of protein, phycobiliprotein, β-carotene, VE and other nutrients needs a certain portion of blue light; yet, the complete blue light condition is not favorable to the growth of Spirulina, and may bring pollution by chlorella and other kinds of micro-algae. It is concluded that the LEDs can be used as the light resource of micro-algae cultivation. The normal growth and development of microalgae need two light sources of both red and blue LEDs. The comprehensive analyses of the various factors that affect the growth of Spirulina, such as nutrition quality and photosynthetic activities, etc., showed that the combination of 80% red and 20% blue LED is the optimum one among those tested combinations. Key word: light-emitting diode; micro-algae; controlled ecological life support system (CELSS); space cultivation

76 FR 77585 - Notice to Manufacturers of Airport Lighting and Navigation Aid Equipment

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-13

...Projects funded under the Airport Improvement Program (AIP) must meet the requirements of 49 U.S.C. 50101, Buy American Preferences. The Federal Aviation Administration (FAA) is considering issuing waivers to foreign manufacturers of certain airport lighting and navigation aid equipment that is lit with Light Emitting Diode (LED) lighting. This notice requests information from manufacturers of systems meeting the technical requirements to determine whether a waiver to the Buy American Preferences should be issued.

X-ray micro-Tomography at the Advanced Light Source

USDA-ARS?s Scientific Manuscript database

The X-ray micro-Tomography Facility at the Advanced Light Source has been in operation since 2004. The source is a superconducting bend magnet of critical energy 10.5KeV; photon energy coverage is 8-45 KeV in monochromatic mode, and a filtered white light option yields useful photons up to 50 KeV. A...

Study on micro-bend light transmission performance of novel liquid-core optical fiber

NASA Astrophysics Data System (ADS)

Ma, Junyan; Zhao, Zhimin; Wang, Kaisheng; Guo, Linfeng

2007-01-01

With the increasing development of material technology and electronic integration technology, optical fiber and its using in smart structure have become hot in the field of material research. And liquid-core optical fiber is a special kind of optical fiber, which is made using liquid material as core and polymer material as optical layer and protective covering, and it has the characteristics of large core diameter, high numerical aperture, large-scope and efficient spectrum transmission and long life for using. So the liquid-core optical fiber is very suitable for spectrum cure, ultraviolet solidification, fluorescence detection, criminal investigation and evidence obtainment, etc, and especially as light transfer element in some new structures for the measurement of some signals, such as concentration, voltage, temperature, light intensity and so on. In this paper, the novel liquid-core optical fiber is self-made, and then through the test of its light transmission performance in free state, the relation between axial micro-bend and light-intensity loss are presented. When the liquid-core optical fiber is micro-bent axially, along with the axial displacement's increase, output power of light is reducing increasingly, and approximately has linear relation to micro-displacement in a range. According to the results liquid-core fiber-optic micro-bend sensor can be designed to measure micro-displacement of the tested objects. Experimental data and analysis provide experimental basis for further application of liquid-core optical fiber.

Combined micro and macro additive manufacturing of a swirling flow coaxial phacoemulsifier sleeve with internal micro-vanes.

PubMed

Choi, Jae-Won; Yamashita, Masaki; Sakakibara, Jun; Kaji, Yuichi; Oshika, Tetsuro; Wicker, Ryan B

2010-10-01

flow with rapidly dissipating streamwise flow velocities where the maximum measured streamwise flow velocities using the micro-vane were lower than those without the micro-vane by 2 mm from the tip where they remained at approximately 70% of those produced by the conventional sleeve as the flow continued to develop. It is believed that this new device will reduce damage to endothelial cells during cataract surgery and significantly improve patient outcomes from this procedure. This unique application demonstrates the utility of combining microSL with a macro rapid prototyping technology for fabricating a real macro-scale device with functional, 3D micro-scale features that would be difficult and costly to fabricate using alternative manufacturing methods.

Micro lens design for efficiency improvement of red organic light-emitting diode

NASA Astrophysics Data System (ADS)

Ki, Hyun-Chul; Kim, Doo-Gun; Kim, Seon-Hoon; Jung, U.-Ra; Kim, Sang-Gi; Hong, Kyung-Jin

2012-11-01

We have proposed a micro lens to improve the luminance of red organic light-emitting devices (ROLEDs). The micro lenses were applied on the glass/indium tin oxide (ITO)/OLED. The size, thickness and diameter of micro lenses were calculated by using FDTD (finite-difference timedomain) method. Simulations were performed for 5 µm and 10 µm sized. The thickness and the gap of the micro lens were both 1 µm. The material of the micro lenses was silicon dioxide. The highest luminance of an OLED applied with a micro lens was 11,185 cd/m2, at on approval voltage of 14.5 V, The efficiency of the device with a micro lens increased by 3 times compared to that of the device with no micro lens.

Design and optimization of the micro-engine turbine rotor manufacturing using the rapid prototyping technology

NASA Astrophysics Data System (ADS)

Vdovin, R. A.; Smelov, V. G.

2017-02-01

This work describes the experience in manufacturing the turbine rotor for the micro-engine. It demonstrates the design principles for the complex investment casting process combining the use of the ProCast software and the rapid prototyping techniques. At the virtual modelling stage, in addition to optimized process parameters, the casting structure was improved to obtain the defect-free section. The real production stage allowed demonstrating the performance and fitness of rapid prototyping techniques for the manufacture of geometrically-complex engine-building parts.

Analysis of light extraction efficiency enhancement for thin-film-flip-chip InGaN quantum wells light-emitting diodes with GaN micro-domes.

PubMed

Zhao, Peng; Zhao, Hongping

2012-09-10

The enhancement of light extraction efficiency for thin-film flip-chip (TFFC) InGaN quantum wells (QWs) light-emitting diodes (LEDs) with GaN micro-domes on n-GaN layer was studied. The light extraction efficiency of TFFC InGaN QWs LEDs with GaN micro-domes were calculated and compared to that of the conventional TFFC InGaN QWs LEDs with flat surface. The three dimensional finite difference time domain (3D-FDTD) method was used to calculate the light extraction efficiency for the InGaN QWs LEDs emitting at 460nm and 550 nm, respectively. The effects of the GaN micro-dome feature size and the p-GaN layer thickness on the light extraction efficiency were studied systematically. Studies indicate that the p-GaN layer thickness is critical for optimizing the TFFC LED light extraction efficiency. Significant enhancement of the light extraction efficiency (2.5-2.7 times for λ(peak) = 460nm and 2.7-2.8 times for λ(peak) = 550nm) is achievable from TFFC InGaN QWs LEDs with optimized GaN micro-dome diameter and height.

Shining a New Light on Silicon PV Manufacturing - Continuum Magazine |

Science.gov Websites

lines. Photo by Dennis Schroeder, NREL Shining a New Light on Silicon PV Manufacturing Groundbreaking system and can be automatically eliminated. Photo by Dennis Schroeder, NREL Tackling the Serious Issue of

Metal vapor micro-jet controls material redistribution in laser powder bed fusion additive manufacturing.

PubMed

Ly, Sonny; Rubenchik, Alexander M; Khairallah, Saad A; Guss, Gabe; Matthews, Manyalibo J

2017-06-22

The results of detailed experiments and finite element modeling of metal micro-droplet motion associated with metal additive manufacturing (AM) processes are presented. Ultra high speed imaging of melt pool dynamics reveals that the dominant mechanism leading to micro-droplet ejection in a laser powder bed fusion AM is not from laser induced recoil pressure as is widely believed and found in laser welding processes, but rather from vapor driven entrainment of micro-particles by an ambient gas flow. The physics of droplet ejection under strong evaporative flow is described using simulations of the laser powder bed interactions to elucidate the experimental results. Hydrodynamic drag analysis is used to augment the single phase flow model and explain the entrainment phenomenon for 316 L stainless steel and Ti-6Al-4V powder layers. The relevance of vapor driven entrainment of metal micro-particles to similar fluid dynamic studies in other fields of science will be discussed.

Metal vapor micro-jet controls material redistribution in laser powder bed fusion additive manufacturing

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

Ly, Sonny; Rubenchik, Alexander M.; Khairallah, Saad A.

The results of detailed experiments and finite element modeling of metal micro-droplet motion associated with metal additive manufacturing (AM) processes are presented. Ultra high speed imaging of melt pool dynamics reveals that the dominant mechanism leading to micro-droplet ejection in a laser powder bed fusion AM is not from laser induced recoil pressure as is widely believed and found in laser welding processes, but rather from vapor driven entrainment of micro-particles by an ambient gas flow. The physics of droplet ejection under strong evaporative flow is described using simulations of the laser powder bed interactions to elucidate the experimental results.more » Hydrodynamic drag analysis is used to augment the single phase flow model and explain the entrainment phenomenon for 316 L stainless steel and Ti-6Al-4V powder layers. The relevance of vapor driven entrainment of metal micro-particles to similar fluid dynamic studies in other fields of science will be discussed.« less

Metal vapor micro-jet controls material redistribution in laser powder bed fusion additive manufacturing

DOE PAGES

Ly, Sonny; Rubenchik, Alexander M.; Khairallah, Saad A.; ...

2017-06-22

The results of detailed experiments and finite element modeling of metal micro-droplet motion associated with metal additive manufacturing (AM) processes are presented. Ultra high speed imaging of melt pool dynamics reveals that the dominant mechanism leading to micro-droplet ejection in a laser powder bed fusion AM is not from laser induced recoil pressure as is widely believed and found in laser welding processes, but rather from vapor driven entrainment of micro-particles by an ambient gas flow. The physics of droplet ejection under strong evaporative flow is described using simulations of the laser powder bed interactions to elucidate the experimental results.more » Hydrodynamic drag analysis is used to augment the single phase flow model and explain the entrainment phenomenon for 316 L stainless steel and Ti-6Al-4V powder layers. The relevance of vapor driven entrainment of metal micro-particles to similar fluid dynamic studies in other fields of science will be discussed.« less

Zinc Sulphide Overlayer Two-Dimensional Photonic Crystal for Enhanced Extraction of Light from a Micro Cavity Light-Emitting Diode

NASA Astrophysics Data System (ADS)

Mastro, Michael A.; Kim, Chul Soo; Kim, Mijin; Caldwell, Josh; Holm, Ron T.; Vurgaftman, Igor; Kim, Jihyun; Eddy, Charles R., Jr.; Meyer, Jerry R.

2008-10-01

A two-dimensional (2D) ZnS photonic crystal was deposited on the surface of a one-dimensional (1D) III-nitride micro cavity light-emitting diode (LED), to intermix the light extraction features of both structures (1D+2D). The deposition of an ideal micro-cavity optical thickness of ≈λ/2 is impractical for III-nitride LEDs, and in realistic multi-mode devices a large fraction of the light is lost to internal refraction as guided light. Therefore, a 2D photonic crystal on the surface of the LED was used to diffract and thus redirect this guided light out of the semiconductor over several hundred microns. Additionally, the employment of a post-epitaxy ZnS 2D photonic crystal avoided the typical etching into the GaN:Mg contact layer, a procedure which can cause damage to the near surface.

Replicative manufacturing of complex lighting optics by non-isothermal glass molding

NASA Astrophysics Data System (ADS)

Kreilkamp, Holger; Vu, Anh Tuan; Dambon, Olaf; Klocke, Fritz

2016-09-01

The advantages of LED lighting, especially its energy efficiency and the long service life have led to a wide distribution of LED technology in the world. However, in order to make fully use of the great potential that LED lighting offers, complex optics are required to distribute the emitted light from the LED efficiently. Nowadays, many applications use polymer optics which can be manufactured at low costs. However, due to ever increasing luminous power, polymer optics reach their technological limits. Due to its outstanding properties, especially its temperature resistance, resistance against UV radiation and its long term stability, glass is the alternative material of choice for the use in LED optics. This research is introducing a new replicative glass manufacturing approach, namely non-isothermal glass molding (NGM) which is able to manufacture complex lighting optics in high volumes at competitive prices. The integration of FEM simulation at the early stage of the process development is presented and helps to guarantee a fast development cycle. A coupled thermo-mechanical model is used to define the geometry of the glass preform as well as to define the mold surface geometry. Furthermore, simulation is used to predict main process outcomes, especially in terms of resulting form accuracy of the molded optics. Experiments conducted on a commercially available molding machine are presented to validate the developed simulation model. Finally, the influence of distinct parameters on important process outcomes like form accuracy, surface roughness, birefringence, etc. is discussed.

Improvement of illumination uniformity for LED flat panel light by using micro-secondary lens array.

PubMed

Lee, Hsiao-Wen; Lin, Bor-Shyh

2012-11-05

LED flat panel light is an innovative lighting product in recent years. However, current flat panel light products still contain some drawbacks, such as narrow lighting areas and hot spots. In this study, a micro-secondary lens array technique was proposed and applied for the design of the light guide surface to improve the illumination uniformity. By using the micro-secondary lens array, the candela distribution of the LED flat panel light can be adjusted to similar to batwing distribution to improve the illumination uniformity. The experimental results show that the enhancement of the floor illumination uniformity is about 61%, and that of the wall illumination uniformity is about 20.5%.

Comparison of prosthetic models produced by traditional and additive manufacturing methods.

PubMed

Park, Jin-Young; Kim, Hae-Young; Kim, Ji-Hwan; Kim, Jae-Hong; Kim, Woong-Chul

2015-08-01

The purpose of this study was to verify the clinical-feasibility of additive manufacturing by comparing the accuracy of four different manufacturing methods for metal coping: the conventional lost wax technique (CLWT); subtractive methods with wax blank milling (WBM); and two additive methods, multi jet modeling (MJM), and micro-stereolithography (Micro-SLA). Thirty study models were created using an acrylic model with the maxillary upper right canine, first premolar, and first molar teeth. Based on the scan files from a non-contact blue light scanner (Identica; Medit Co. Ltd., Seoul, Korea), thirty cores were produced using the WBM, MJM, and Micro-SLA methods, respectively, and another thirty frameworks were produced using the CLWT method. To measure the marginal and internal gap, the silicone replica method was adopted, and the silicone images obtained were evaluated using a digital microscope (KH-7700; Hirox, Tokyo, Japan) at 140X magnification. Analyses were performed using two-way analysis of variance (ANOVA) and Tukey post hoc test (α=.05). The mean marginal gaps and internal gaps showed significant differences according to tooth type (P<.001 and P<.001, respectively) and manufacturing method (P<.037 and P<.001, respectively). Micro-SLA did not show any significant difference from CLWT regarding mean marginal gap compared to the WBM and MJM methods. The mean values of gaps resulting from the four different manufacturing methods were within a clinically allowable range, and, thus, the clinical use of additive manufacturing methods is acceptable as an alternative to the traditional lost wax-technique and subtractive manufacturing.

Manufacture of micro fluidic devices by laser welding using thermal transfer printing techniques

NASA Astrophysics Data System (ADS)

Klein, R.; Klein, K. F.; Tobisch, T.; Thoelken, D.; Belz, M.

2016-03-01

Micro-fluidic devices are widely used today in the areas of medical diagnostics and drug research, as well as for applications within the process, electronics and chemical industry. Microliters of fluids or single cell to cell interactions can be conveniently analyzed with such devices using fluorescence imaging, phase contrast microscopy or spectroscopic techniques. Typical micro-fluidic devices consist of a thermoplastic base component with chambers and channels covered by a hermetic fluid and gas tight sealed lid component. Both components are usually from the same or similar thermoplastic material. Different mechanical, adhesive or thermal joining processes can be used to assemble base component and lid. Today, laser beam welding shows the potential to become a novel manufacturing opportunity for midsize and large scale production of micro-fluidic devices resulting in excellent processing quality by localized heat input and low thermal stress to the device during processing. For laser welding, optical absorption of the resin and laser wavelength has to be matched for proper joining. This paper will focus on a new approach to prepare micro-fluidic channels in such devices using a thermal transfer printing process, where an optical absorbing layer absorbs the laser energy. Advantages of this process will be discussed in combination with laser welding of optical transparent micro-fluidic devices.

An intraocular micro light-emitting diode device for endo-illumination during pars plana vitrectomy.

PubMed

Koelbl, Philipp S; Lingenfelder, Christian; Spraul, Christoph W; Kampmeier, Juergen; Koch, Frank Hj; Kim, Yong Keun; Hessling, Martin

2018-03-01

Development of a new, fiber-free, single-use endo-illuminator for pars plana vitrectomy as a replacement for fiber-based systems with external light sources. The hand-guided intraocularly placed white micro light-emitting diode is evaluated for its illumination properties and potential photochemical and thermal hazards. A micro light-emitting diode was used to develop a single-use intraocular illumination system. The light-source-on-tip device was implemented in a prototype with 23G trocar compatible outer diameter of 0.6 mm. The experimental testing was performed on porcine eyes. All calculations of possible photochemical and thermal hazards during the application of the intraocular micro light-emitting diode were calculated according to DIN EN ISO 15007-2: 2014. The endo-illuminator generated a homogeneous and bright illumination of the intraocular space. The color impression was physiologic and natural. Contrary to initial apprehension, the possible risk caused by inserting a light-emitting diode into the intraocular vitreous was much smaller when compared to conventional fiber-based illumination systems. The photochemical and thermal hazards allowed a continuous exposure time to the retina of at least 4.7 h. This first intraocular light source showed that a light-emitting diode can be introduced into the eye. The system can be built as single-use illumination system. This light-source-on-tip light-emitting diode-endo-illumination combines a chandelier wide-angle illumination with an adjustable endo-illuminator.

Morphologies and optical and electrical properties of InGaN/GaN micro-square array light-emitting diode chips.

PubMed

Han, Dan; Ma, Shufang; Jia, Zhigang; Liu, Peizhi; Jia, Wei; Shang, Lin; Zhai, Guangmei; Xu, Bingshe

2018-04-10

InGaN/GaN micro-square array light-emitting diode (LED) chips (micro-chips) have been prepared via the focused ion beam (FIB) etching technique, which can not only reduce ohmic contact degradation but also control the aspect ratio precisely in three-dimensional (3D) structure LED (3D-LED) device fabrication. The effects of FIB beam current and micro-square array depth on morphologies and optical and electrical properties of the micro-chips have been studied. Our results show that sidewall surface morphology and optical and electrical properties of the micro-chips degrade with increased beam current. After potassium hydroxide etching with different times, an optimal current-voltage and luminescence performance can be obtained. Combining the results of cathodoluminescence mappings and light output-current characteristics, the light extraction efficiency of the micro-chips is reduced as FIB etch depth increases. The mechanisms of micro-square depth on light extraction have been revealed by 3D finite difference time domain.

Micro-fabricated integrated coil and magnetic circuit and method of manufacturing thereof

DOEpatents

Mihailovich, Robert E.; Papavasiliou, Alex P.; Mehrotra, Vivek; Stupar, Philip A.; Borwick, III, Robert L.; Ganguli, Rahul; DeNatale, Jeffrey F.

2017-03-28

A micro-fabricated electromagnetic device is provided for on-circuit integration. The electromagnetic device includes a core. The core has a plurality of electrically insulating layers positioned alternatingly between a plurality of magnetic layers to collectively form a continuous laminate having alternating magnetic and electrically insulating layers. The electromagnetic device includes a coil embedded in openings of the semiconductor substrate. An insulating material is positioned in the cavity and between the coil and an inner surface of the core. A method of manufacturing the electromagnetic device includes providing a semiconductor substrate having openings formed therein. Windings of a coil are electroplated and embedded in the openings. The insulating material is coated on or around an exposed surface of the coil. Alternating magnetic layers and electrically insulating layers may be micro-fabricated and electroplated as a single and substantially continuous segment on or around the insulating material.

Aging characteristics of blue InGaN micro-light emitting diodes at an extremely high current density of 3.5 kA cm-2

NASA Astrophysics Data System (ADS)

Tian, Pengfei; Althumali, Ahmad; Gu, Erdan; Watson, Ian M.; Dawson, Martin D.; Liu, Ran

2016-04-01

The aging characteristics of blue InGaN micro-light emitting diodes (micro-LEDs) with different sizes have been studied at an extremely high current density 3.5 kA cm-2 for emerging micro-LED applications including visible light communication (VLC), micro-LED pumped organic lasers and optogenetics. The light output power of micro-LEDs first increases and then decreases due to the competition of Mg activation in p-GaN layer and defect generation in the active region. The smaller micro-LEDs show less light output power degradation compared with larger micro-LEDs, which is attributed to the lower junction temperature of smaller micro-LEDs. It is found that the high current density without additional junction temperature cannot induce significant micro-LED degradation at room temperature but the combination of the high current density and high junction temperature leads to strong degradation. Furthermore, the cluster LEDs, composed of a micro-LED array, have been developed with both high light output power and less light output degradation for micro-LED applications in solid state lighting and VLC.

Manufacture of gradient micro-structures of magnesium alloys using two stage extrusion dies

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

Hwang, Yeong-Maw; Huang, Tze-Hui; Alexandrov, Sergei

2013-12-16

This paper aims to manufacture magnesium alloy metals with gradient micro-structures using hot extrusion process. The extrusion die was designed to have a straight channel part combined with a conical part. Materials pushed through this specially-designed die generate a non-uniform velocity distribution at cross sections inside the die and result in different strain and strain rate distributions. Accordingly, a gradient microstructure product can be obtained. Using the finite element analysis, the forming temperature, effective strain, and effective strain rate distributions at the die exit were firstly discussed for various inclination angles in the conical die. Then, hot extrusion experiments withmore » a two stage die were conducted to obtain magnesium alloy products with gradient micro-structures. The effects of the inclination angle on the grain size distribution at cross sections of the products were also discussed. Using a die of an inclination angle of 15°, gradient micro-structures of the grain size decreasing gradually from 17 μm at the center to 4 μm at the edge of product were achieved.« less

Diode-based additive manufacturing of metals using an optically-addressable light valve.

PubMed

Matthews, Manyalibo J; Guss, Gabe; Drachenberg, Derrek R; Demuth, James A; Heebner, John E; Duoss, Eric B; Kuntz, Joshua D; Spadaccini, Christopher M

2017-05-15

Selective Laser Melting (SLM) of metal powder bed layers, whereby 3D metal objects can be printed from a digital file with unprecedented design flexibility, is spurring manufacturing innovations in medical, automotive, aerospace and textile industries. Because SLM is based on raster-scanning a laser beam over each layer, the process is relatively slow compared to most traditional manufacturing methods (hours to days), thus limiting wider spread use. Here we demonstrate the use of a large area, photolithographic method for 3D metal printing, using an optically-addressable light valve (OALV) as the photomask, to print entire layers of metal powder at once. An optical sheet of multiplexed ~5 kW, 20 ms laser diode and ~1 MW, 7 ns Q-switched laser pulses are used to selectively melt each layer. The patterning of near infrared light is accomplished by imaging 470 nm light onto the transmissive OALV, which consists of polarization-selective nematic liquid crystal sandwiched between a photoconductor and transparent conductor for switching.

From Extended Nanofluidics to an Autonomous Solar-Light-Driven Micro Fuel-Cell Device.

PubMed

Pihosh, Yuriy; Uemura, Jin; Turkevych, Ivan; Mawatari, Kazuma; Kazoe, Yutaka; Smirnova, Adelina; Kitamori, Takehiko

2017-07-03

Autonomous micro/nano mechanical, chemical, and biomedical sensors require persistent power sources scaled to their size. Realization of autonomous micro-power sources is a challenging task, as it requires combination of wireless energy supply, conversion, storage, and delivery to the sensor. Herein, we realized a solar-light-driven power source that consists of a micro fuel cell (μFC) and a photocatalytic micro fuel generator (μFG) integrated on a single microfluidic chip. The μFG produces hydrogen by photocatalytic water splitting under solar light. The hydrogen fuel is then consumed by the μFC to generate electricity. Importantly, the by-product water returns back to the photocatalytic μFG via recirculation loop without losses. Both devices rely on novel phenomena in extended-nano-fluidic channels that ensure ultra-fast proton transport. As a proof of concept, we demonstrate that μFG/μFC source achieves remarkable energy density of ca. 17.2 mWh cm -2 at room temperature. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Relationships of microRNA expression in mouse lung with age and exposure to cigarette smoke and light

PubMed Central

Izzotti, Alberto; Calin, George A.; Steele, Vernon E.; Croce, Carlo M.; De Flora, Silvio

2009-01-01

MicroRNAs provide a formidable tool not only in cancer research but also to investigate physiological mechanisms and to assess the effect of environmental exposures in healthy tissues. Collectively, cigarette smoke and sunlight have been estimated to account for 40% of all human cancers, and not only smoke but also, surprisingly, UV light induced genomic and postgenomic alterations in mouse lung. Here we evaluated by microarray the expression of 484 microRNAs in the lungs of CD-1 mice, including newborns, postweanling males and females, and their dams, either untreated or exposed to environmental cigarette smoke and/or UV-containing light. The results obtained highlighted age-related variations in microRNA profiles, especially during the weanling period, due to perinatal stress and postnatal maturation of the lung. UV light alone did not affect pulmonary microRNAs, whereas smoke produced dramatic changes, mostly in the sense of down-regulation, reflecting both adaptive mechanisms and activation of pathways involved in the pathogenesis of pulmonary diseases. Both gender and age affected smoke-related microRNA dysregulation in mice. The data presented provide supporting evidence that microRNAs play a fundamental role in both physiological and pathological changes occurring in mouse lung.—Izzotti, A., Calin, G. A., Vernon E. St., Croce, G. M., De Flora, S. Relationships of microRNA expression in mouse lung with age and exposure to cigarette smoke and light. PMID:19465468

Relationships of microRNA expression in mouse lung with age and exposure to cigarette smoke and light.

PubMed

Izzotti, Alberto; Calin, George A; Steele, Vernon E; Croce, Carlo M; De Flora, Silvio

2009-09-01

MicroRNAs provide a formidable tool not only in cancer research but also to investigate physiological mechanisms and to assess the effect of environmental exposures in healthy tissues. Collectively, cigarette smoke and sunlight have been estimated to account for 40% of all human cancers, and not only smoke but also, surprisingly, UV light induced genomic and postgenomic alterations in mouse lung. Here we evaluated by microarray the expression of 484 microRNAs in the lungs of CD-1 mice, including newborns, postweanling males and females, and their dams, either untreated or exposed to environmental cigarette smoke and/or UV-containing light. The results obtained highlighted age-related variations in microRNA profiles, especially during the weanling period, due to perinatal stress and postnatal maturation of the lung. UV light alone did not affect pulmonary microRNAs, whereas smoke produced dramatic changes, mostly in the sense of down-regulation, reflecting both adaptive mechanisms and activation of pathways involved in the pathogenesis of pulmonary diseases. Both gender and age affected smoke-related microRNA dysregulation in mice. The data presented provide supporting evidence that microRNAs play a fundamental role in both physiological and pathological changes occurring in mouse lung.

Precision laser processing for micro electronics and fiber optic manufacturing

NASA Astrophysics Data System (ADS)

Webb, Andrew; Osborne, Mike; Foster-Turner, Gideon; Dinkel, Duane W.

2008-02-01

The application of laser based materials processing for precision micro scale manufacturing in the electronics and fiber optic industry is becoming increasingly widespread and accepted. This presentation will review latest laser technologies available and discuss the issues to be considered in choosing the most appropriate laser and processing parameters. High repetition rate, short duration pulsed lasers have improved rapidly in recent years in terms of both performance and reliability enabling flexible, cost effective processing of many material types including metal, silicon, plastic, ceramic and glass. Demonstrating the relevance of laser micromachining, application examples where laser processing is in use for production will be presented, including miniaturization of surface mount capacitors by applying a laser technique for demetalization of tracks in the capacitor manufacturing process and high quality laser machining of fiber optics including stripping, cleaving and lensing, resulting in optical quality finishes without the need for traditional polishing. Applications include telecoms, biomedical and sensing. OpTek Systems was formed in 2000 and provide fully integrated systems and sub contract services for laser processes. They are headquartered in the UK and are establishing a presence in North America through a laser processing facility in South Carolina and sales office in the North East.

Light propagation in the micro-size capillary injected by high temperature liquid

NASA Astrophysics Data System (ADS)

Li, Yan-jun; Li, Edward; Xiao, Hai

2016-11-01

The high temperature liquid is injected into the micro-size capillary and its light propagation behavior is investigated. We focus on two different liquid pumping methods. The first method can pump the high temperature liquid tin into the micro-size capillary by using a high pressure difference system. After pumping, a single mode fiber (SMF) connected with the optical carrier based microwave interferometry (OCMI) system is used to measure different liquid tin levels in the micro-size capillary. The second method can pump the room temperature engine oil into the capillary by using a syringe pump. This method can avoid the air bubbles when the liquids are pumped into the capillary.

Diode-based additive manufacturing of metals using an optically-addressable light valve

DOE PAGES

Matthews, Manyalibo J.; Guss, Gabe; Drachenberg, Derrek R.; ...

2017-05-10

We present that Selective Laser Melting (SLM) of metal powder bed layers, whereby 3D metal objects can be printed from a digital file with unprecedented design flexibility, is spurring manufacturing innovations in medical, automotive, aerospace and textile industries. Because SLM is based on raster-scanning a laser beam over each layer, the process is relatively slow compared to most traditional manufacturing methods (hours to days), thus limiting wider spread use. Here we demonstrate the use of a large area, photolithographic method for 3D metal printing, using an optically-addressable light valve (OALV) as the photomask, to print entire layers of metal powdermore » at once. An optical sheet of multiplexed ~5 kW, 20 ms laser diode and ~1 MW, 7 ns Q-switched laser pulses are used to selectively melt each layer. Finally, the patterning of near infrared light is accomplished by imaging 470 nm light onto the transmissive OALV, which consists of polarization-selective nematic liquid crystal sandwiched between a photoconductor and transparent conductor for switching.« less

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.

Array servo scanning micro EDM of 3D micro cavities

NASA Astrophysics Data System (ADS)

Tong, Hao; Li, Yong; Yi, Futing

2011-05-01

Micro electro discharge machining (Micro EDM) is a non-traditional processing technology with the special advantages of low set-up cost and few cutting force in machining any conductive materials regardless of their hardness. As well known, die-sinking EDM is unsuitable for machining the complex 3D micro cavity less than 1mm due to the high-priced fabrication of 3D microelectrode itself and its serous wear during EDM process. In our former study, a servo scanning 3D micro-EDM (3D SSMEDM) method was put forward, and our experiments showed it was available to fabricate complex 3D micro-cavities. In this study, in order to improve machining efficiency and consistency accuracy for array 3D micro-cavities, an array-servo-scanning 3D micro EDM (3D ASSMEDM) method is presented considering the complementary advantages of the 3D SSMEDM and the array micro electrodes with simple cross-section. During 3D ASSMEDM process, the array cavities designed by CAD / CAM system can be batch-manufactured by servo scanning layer by layer using array-rod-like micro tool electrodes, and the axial wear of the array electrodes is compensated in real time by keeping discharge gap. To verify the effectiveness of the 3D ASSMEDM, the array-triangle-micro cavities (side length 630 μm) are batch-manufactured on P-doped silicon by applying the array-micro-electrodes with square-cross-section fabricated by LIGA process. Our exploratory experiment shows that the 3D ASSMEDM provides a feasible approach for the batch-manufacture of 3D array-micro-cavities of conductive materials.

Determination of the Acceptable Ambient Light Exposure during Drug Product Manufacturing for Long Term Stability of Monoclonal Antibodies.

PubMed

Luis, Lin M; Hu, Yuzhe; Zamiri, Camellia; Sreedhara, Alavattam

2018-05-31

Monoclonal antibodies (mAbs) are exposed to light during drug product (DP) manufacturing and the acceptable levels of light exposure needs to be determined based on the impact on product quality. In this study, a mild and more representative light model consisting of ambient light instead of stress light as prescribed by ICH Q1B was used to evaluate the impact of light exposure on mAb DP quality. The immediate effect of ambient light exposure on protein drug product quality was determined to be dependent on the amount of light exposure rather than light intensity (up to 5000 lux). The impact on quality of mAbs is product specific due to their differences in light sensitivity, in which mAb II shows larger increases in IEC basic variants and larger decreases in SEC monomer when compared to mAb I after 0.24 million lux hours of light exposure. The acceptable ambient light exposure for mAb II drug product manufacturing was determined to be 0.13 million lux hours, in which no impact on product quality was observed after the short-term light exposure. Additionally, real-time storage (5°C) of the DP after the prescribed ambient light exposure showed no impact to various product quality attributes. The light model used in this study is capable of determining the acceptable amount of ambient light exposure for mAbs, especially during DP manufacturing processes. Copyright © 2018, Parenteral Drug Association.

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

Light propagation in the Solar System for astrometry on sub-micro-arcsecond level

NASA Astrophysics Data System (ADS)

Zschocke, Sven

2018-04-01

We report on recent advancement in the theory of light propagation in the Solar System aiming at sub-micro-arcsecond level of accuracy: (1) A solution for the light ray in 1.5PN approximation has been obtained in the field of N arbitrarily moving bodies of arbitrary shape, inner structure, oscillations, and rotational motion. (2) A solution for the light ray in 2PN approximation has been obtained in the field of one arbitrarily moving pointlike body.

Dimensional metrology of smooth micro structures utilizing the spatial modulation of white-light interference fringes

NASA Astrophysics Data System (ADS)

Zhou, Yi; Tang, Yan; Deng, Qinyuan; Liu, Junbo; Wang, Jian; Zhao, Lixin

2017-08-01

Dimensional metrology for micro structure plays an important role in addressing quality issues and observing the performance of micro-fabricated products. In white light interferometry, the proposed method is expected to measure three-dimensional topography through modulation depth in spatial frequency domain. A normalized modulation depth is first obtained in the xy plane (image plane) for each CCD image individually. After that, the modulation depth of each pixel is analyzed along the scanning direction (z-axis) to reshape the topography of micro samples. Owing to the characteristics of modulation depth in broadband light interferometry, the method could effectively suppress the negative influences caused by light fluctuations and external irradiance disturbance. Both theory and experiments are elaborated in detail to verify that the modulation depth-based method can greatly level up the stability and sensitivity with satisfied precision in the measurement system. This technique can achieve an improved robustness in a complex measurement environment with the potential to be applied in online topography measurement such as chemistry and medical domains.

Light-Driven Nano-oscillators for Label-Free Single-Molecule Monitoring of MicroRNA.

PubMed

Chen, Zixuan; Peng, Yujiao; Cao, Yue; Wang, Hui; Zhang, Jian-Rong; Chen, Hong-Yuan; Zhu, Jun-Jie

2018-06-13

Here, we present a mapping tool based on individual light-driven nano-oscillators for label-free single-molecule monitoring of microRNA. This design uses microRNA as a single-molecule damper for nano-oscillators by forming a rigid dual-strand structure in the gap between nano-oscillators and the immobilized surface. The ultrasensitive detection is attributed to comparable dimensions of the gap and microRNA. A developed surface plasmon-coupled scattering imaging technology enables us to directly measure the real-time gap distance vibration of multiple nano-oscillators with high accuracy and fast dynamics. High-level and low-level states of the oscillation amplitude indicate melting and hybridization statuses of microRNA. Lifetimes of two states reveal that the hybridization rate of microRNA is determined by the three-dimensional diffusion. This imaging technique contributes application potentials in a single-molecule detection and nanomechanics study.

Innovative High-Performance Deposition Technology for Low-Cost Manufacturing of OLED Lighting

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

Hamer, John; Scott, David

In this project, OLEDWorks developed and demonstrated the innovative high-performance deposition technology required to deliver dramatic reductions in the cost of manufacturing OLED lighting in production equipment. The current high manufacturing cost of OLED lighting is the most urgent barrier to its market acceptance. The new deposition technology delivers solutions to the two largest parts of the manufacturing cost problem – the expense per area of good product for organic materials and for the capital cost and depreciation of the equipment. Organic materials cost is the largest expense item in the bill of materials and is predicted to remain somore » through 2020. The high-performance deposition technology developed in this project, also known as the next generation source (NGS), increases material usage efficiency from 25% found in current Gen2 deposition technology to 60%. This improvement alone results in a reduction of approximately 25 USD/m 2 of good product in organic materials costs, independent of production volumes. Additionally, this innovative deposition technology reduces the total depreciation cost from the estimated value of approximately 780 USD/m 2 of good product for state-of-the-art G2 lines (at capacity, 5-year straight line depreciation) to 170 USD/m 2 of good product from the OLEDWorks production line.« less

Improving performance of Si/CdS micro-/nanoribbon p-n heterojunction light emitting diodes by trenched structure

NASA Astrophysics Data System (ADS)

Huang, Shiyuan; Wu, Yuanpeng; Ma, Xiangyang; Yang, Zongyin; Liu, Xu; Yang, Qing

2018-05-01

Realizing high performance silicon based light sources has been an unremitting pursuit for researchers. In this letter, we propose a simple structure to enhance electroluminescence emission and reduce the threshold of injected current of silicon/CdS micro-/nanoribbon p-n heterojunction visible light emitting diodes, by fabricating trenched structure on silicon substrate to mount CdS micro-/nanoribbon. A series of experiments and simulation analysis favors the rationality and validity of our mounting design. After mounting the CdS micro-/nanoribbon, the optical field confinement increases, and absorption and losses from high refractive silicon substrate are effectively reduced. Meanwhile the sharp change of silicon substrate near heterojunction also facilitates the balance between electron current and hole current, which substantially conduces to the stable amplification of electroluminescence emission in CdS micro-/nanoribbon.

Investigations on the micro-scale surface interactions at the tool and workpiece interface in micro-manufacturing of bipolar plates for proton exchange membrane fuel cells

NASA Astrophysics Data System (ADS)

Peker, Mevlut Fatih

the surface topography changes during long-run micro-stamping of BPPs, and establish relationships between surface roughness--corrosion resistance and surface roughness-contact resistance characteristics of BPPs. Formability levels of formed BPPs and repeatability characteristics of the process were investigated. In addition, blank thickness changes, von-Mises stress, plastic strain levels and distributions of micro-stamping process were determined via finite element analysis (FEA). Test results revealed that the surface roughness change for the stamping dies and BPPs was unsteady (no trend) due to the continuous change of surface topography (i.e. asperity deformation). Sub-micron range local plastic deformations on stamping dies led to surface topography changes on BPP in long-run manufacturing case. As surface defects trigger corrosion, the correlation between surface roughness and corrosion resistance of BPPs was found to be direct. Increasing number of surface irregularities (asperities) lowered contact surface area that resulted in increased contact resistance. ZrN coated BPPs, on the other hand, did not change surface roughness, however; it improved the protection of BPPs against corrosion significantly. In addition, ZrN coating increased the conductivity of BPPs and reduced the contact resistance between BPP and gas diffusion layer (GDL), at certain extent. As dimensional stability and repeatability was confirmed in forming of both uncoated and coated BPPs during the long run manufacturing, different formability levels were achieved for coated and uncoated samples. Lower channel height values were obtained for coated plates because of the different surface hardness of uncoated and coated plates. In tribological size effect part of study, micro stamping experiments using three different dies with distinct channel height values at different stamping force levels were performed. It was concluded that decrease in forming die dimensions led to increase in

On-chip micro-power: three-dimensional structures for micro-batteries and micro-supercapacitors

NASA Astrophysics Data System (ADS)

Beidaghi, Majid; Wang, Chunlei

2010-04-01

With the miniaturization of portable electronic devices, there is a demand for micro-power source which can be integrated on the semiconductor chips. Various micro-batteries have been developed in recent years to generate or store the energy that is needed by microsystems. Micro-supercapacitors are also developed recently to couple with microbatteries and energy harvesting microsystems and provide the peak power. Increasing the capacity per footprint area of micro-batteries and micro-supercapacitors is a great challenge. One promising route is the manufacturing of three dimensional (3D) structures for these micro-devices. In this paper, the recent advances in fabrication of 3D structure for micro-batteries and micro-supercapacitors are briefly reviewed.

The numerical simulation and experiment on extrusion roller embossing of light diffusion plate with micro-structure

NASA Astrophysics Data System (ADS)

Zang, Gongzheng; Fu, Zhihong; Zhang, Lei; Wan, Yue

2018-01-01

Extrusion roller embossing process has demonstrated the ability to produce polymer film with micro-structure. However the influence of various parameters on the forming quality has not been understood clearly. In this paper, a light diffusion plate with semi cylindrical micro-structure array as the research object, the influence of the main processing parameters such as roller speed, pressuring distance and polymer film temperature to the rolling quality was investigated in detail by simulation and experimental methods. The results show that the thickness of the light diffusion plate and the micro-structure fitting diameter increases with the increasing of the roll speed and the polymer film temperature, and decreases with the increasing of the pressing distance. Besides, the simulation results conformed well to the experimental results.

Modular Elastomer Photoresins for Digital Light Processing Additive Manufacturing.

PubMed

Thrasher, Carl J; Schwartz, Johanna J; Boydston, Andrew J

2017-11-15

A series of photoresins suitable for the production of elastomeric objects via digital light processing additive manufacturing are reported. Notably, the printing procedure is readily accessible using only entry-level equipment under ambient conditions using visible light projection. The photoresin formulations were found to be modular in nature, and straightforward adjustments to the resin components enabled access to a range of compositions and mechanical properties. Collectively, the series includes silicones, hydrogels, and hybrids thereof. Printed test specimens displayed maximum elongations of up to 472% under tensile load, a tunable swelling behavior in water, and Shore A hardness values from 13.7 to 33.3. A combination of the resins was used to print a functional multimaterial three-armed pneumatic gripper. These photoresins could be transformative to advanced prototyping applications such as simulated human tissues, stimuli-responsive materials, wearable devices, and soft robotics.

Micro-valve pump light valve display

DOEpatents

Yeechun Lee.

1993-01-19

A flat panel display incorporates a plurality of micro-pump light valves (MLV's) to form pixels for recreating an image. Each MLV consists of a dielectric drop sandwiched between substrates, at least one of which is transparent, a holding electrode for maintaining the drop outside a viewing area, and a switching electrode from accelerating the drop from a location within the holding electrode to a location within the viewing area. The sustrates may further define non-wetting surface areas to create potential energy barriers to assist in controlling movement of the drop. The forces acting on the drop are quadratic in nature to provide a nonlinear response for increased image contrast. A crossed electrode structure can be used to activate the pixels whereby a large flat panel display is formed without active driver components at each pixel.

Micro-valve pump light valve display

DOEpatents

Lee, Yee-Chun

1993-01-01

A flat panel display incorporates a plurality of micro-pump light valves (MLV's) to form pixels for recreating an image. Each MLV consists of a dielectric drop sandwiched between substrates, at least one of which is transparent, a holding electrode for maintaining the drop outside a viewing area, and a switching electrode from accelerating the drop from a location within the holding electrode to a location within the viewing area. The sustrates may further define non-wetting surface areas to create potential energy barriers to assist in controlling movement of the drop. The forces acting on the drop are quadratic in nature to provide a nonlinear response for increased image contrast. A crossed electrode structure can be used to activate the pixels whereby a large flat panel display is formed without active driver components at each pixel.

All-inkjet-printed flexible ZnO micro photodetector for a wearable UV monitoring device.

PubMed

Tran, Van-Thai; Wei, Yuefan; Yang, Hongyi; Zhan, Zhaoyao; Du, Hejun

2017-03-03

Fabrication of small-sized patterns of inorganic semiconductor onto flexible substrates is a major concern when manufacturing wearable devices for measuring either biometric or environmental parameters. In this study, micro-sized flexible ZnO UV photodetectors have been thoroughly prepared by a facile inkjet printing technology and followed with heat treatments. A simple ink recipe of zinc acetate precursor solution was investigated. It is found that the substrate temperature during zinc precursor ink depositing has significant effects on ZnO pattern shape, film morphology, and crystallization. The device fabricated from the additive manufacturing approach has good bendability, Ohmic contact, short response time as low as 0.3 s, and high on/off ratio of 3525. We observed the sensor's dependence of response/decay time by the illuminating UV light intensity. The whole process is based on additive manufacturing which has many benefits such as rapid prototyping, saving material, being environmentally friendly, and being capable of creating high-resolution patterns. In addition, this method can be applied to flexible substrates, which makes the device more applicable for applications requiring flexibility such as wearable devices. The proposed all-inkjet-printing approach for a micro-sized ZnO UV photodetector would significantly simplify the fabrication process of micro-sized inorganic semiconductor-based devices. A potential application is real-time monitoring of UV light exposure to warn users about unsafe direct sunlight to implement suitable avoidance solutions.

All-inkjet-printed flexible ZnO micro photodetector for a wearable UV monitoring device

NASA Astrophysics Data System (ADS)

Tran, Van-Thai; Wei, Yuefan; Yang, Hongyi; Zhan, Zhaoyao; Du, Hejun

2017-03-01

Fabrication of small-sized patterns of inorganic semiconductor onto flexible substrates is a major concern when manufacturing wearable devices for measuring either biometric or environmental parameters. In this study, micro-sized flexible ZnO UV photodetectors have been thoroughly prepared by a facile inkjet printing technology and followed with heat treatments. A simple ink recipe of zinc acetate precursor solution was investigated. It is found that the substrate temperature during zinc precursor ink depositing has significant effects on ZnO pattern shape, film morphology, and crystallization. The device fabricated from the additive manufacturing approach has good bendability, Ohmic contact, short response time as low as 0.3 s, and high on/off ratio of 3525. We observed the sensor’s dependence of response/decay time by the illuminating UV light intensity. The whole process is based on additive manufacturing which has many benefits such as rapid prototyping, saving material, being environmentally friendly, and being capable of creating high-resolution patterns. In addition, this method can be applied to flexible substrates, which makes the device more applicable for applications requiring flexibility such as wearable devices. The proposed all-inkjet-printing approach for a micro-sized ZnO UV photodetector would significantly simplify the fabrication process of micro-sized inorganic semiconductor-based devices. A potential application is real-time monitoring of UV light exposure to warn users about unsafe direct sunlight to implement suitable avoidance solutions.

Manipulation of Micro Scale Particles in Optical Traps Using Programmable Spatial Light Modulation

NASA Technical Reports Server (NTRS)

Seibel, Robin E.; Decker, Arthur J. (Technical Monitor)

2003-01-01

1064 nm light, from an Nd:YAG laser, was polarized and incident upon a programmable parallel aligned liquid crystal spatial light modulator (PAL-SLM), where it was phase modulated according to the program controlling the PAL-SLM. Light reflected from the PAL-SLM was injected into a microscope and focused. At the focus, multiple optical traps were formed in which 9.975 m spheres were captured. The traps and the spheres were moved by changing the program of the PAL-SLM. The motion of ordered groups of micro particles was clearly demonstrated.

Active tracking system for visible light communication using a GaN-based micro-LED and NRZ-OOK.

PubMed

Lu, Zhijian; Tian, Pengfei; Chen, Hong; Baranowski, Izak; Fu, Houqiang; Huang, Xuanqi; Montes, Jossue; Fan, Youyou; Wang, Hongyi; Liu, Xiaoyan; Liu, Ran; Zhao, Yuji

2017-07-24

Visible light communication (VLC) holds the promise of a high-speed wireless network for indoor applications and competes with 5G radio frequency (RF) system. Although the breakthrough of gallium nitride (GaN) based micro-light-emitting-diodes (micro-LEDs) increases the -3dB modulation bandwidth exceptionally from tens of MHz to hundreds of MHz, the light collected onto a fast photo receiver drops dramatically, which determines the signal to noise ratio (SNR) of VLC. To fully implement the practical high data-rate VLC link enabled by a GaN-based micro-LED, it requires focusing optics and a tracking system. In this paper, we demonstrate an active on-chip tracking system for VLC using a GaN-based micro-LED and none-return-to-zero on-off keying (NRZ-OOK). Using this novel technique, the field of view (FOV) was enlarged to 120° and data rates up to 600 Mbps at a bit error rate (BER) of 2.1×10 -4 were achieved without manual focusing. This paper demonstrates the establishment of a VLC physical link that shows enhanced communication quality by orders of magnitude, making it optimized for practical communication applications.

A study of female Mexican anthropometric measures useful for workstation design in light manufacturing facilities.

PubMed

Lavender, S A; Marras, W S; Sabol, R J

2002-01-01

As more and more manufacturing is moved to Mexico, the need for anthropometric data describing the Mexican working population becomes more pronounced. The purpose of this study was to obtain data on 21 anthropometric measures that could readily be used to design workplaces in light manufacturing operations. Eighty-seven females, representing 26% of the plant's employees, were sampled. Measurements were made with the shoes on. The mean stature (height) and elbow heights of this sample were 156 cm and 97 cm. Another recently published survey of female factory workers near the U.S. border included 12 anthropometric dimensions. Five of the dimensions were measured in both studies. Hand lengths were nearly identical; however, the 2 to 3 cm differences in the heights measured in the current study are consistent with the incorporation of the footwear in the current measurements. Thus, this study adds to the growing database that can be used when designing these light manufacturing jobs in Mexico.

Micro-light-pipe array with an excitation attenuation filter for lensless digital enzyme-linked immunosorbent assay

NASA Astrophysics Data System (ADS)

Takehara, Hironari; Nagasaki, Mizuki; Sasagawa, Kiyotaka; Takehara, Hiroaki; Noda, Toshihiko; Tokuda, Takashi; Ohta, Jun

2016-03-01

Digital enzyme-linked immunosorbent assay (ELISA) is used for detecting various biomarkers with hypersensitivity. We have been developing compact systems by replacing the fluorescence microscope with a CMOS image sensor. Here, we propose a micro-light-pipe array structure made of metal filled with dye-doped resin, which can be used as a fabrication substrate of the micro-reaction-chamber array of digital ELISA. The possibility that this structure enhances the coupling efficiency for fluorescence was simulated using a simple model. To realize the structure, we fabricated a 30-µm-thick micropipe array by copper electroplating around a thick photoresist pattern. The typical diameter of each fabricated micropipe was 10 µm. The pipes were filled with yellow-dye-doped epoxy resin. The transmittance ratio of fluorescence and excitation light could be controlled by adjusting the doping concentration. We confirmed that an angled excitation light incidence suppressed the leakage of excitation light.

Macro-/Micro-Controlled 3D Lithium-Ion Batteries via Additive Manufacturing and Electric Field Processing.

PubMed

Li, Jie; Liang, Xinhua; Liou, Frank; Park, Jonghyun

2018-01-30

This paper presents a new concept for making battery electrodes that can simultaneously control macro-/micro-structures and help address current energy storage technology gaps and future energy storage requirements. Modern batteries are fabricated in the form of laminated structures that are composed of randomly mixed constituent materials. This randomness in conventional methods can provide a possibility of developing new breakthrough processing techniques to build well-organized structures that can improve battery performance. In the proposed processing, an electric field (EF) controls the microstructures of manganese-based electrodes, while additive manufacturing controls macro-3D structures and the integration of both scales. The synergistic control of micro-/macro-structures is a novel concept in energy material processing that has considerable potential for providing unprecedented control of electrode structures, thereby enhancing performance. Electrochemical tests have shown that these new electrodes exhibit superior performance in their specific capacity, areal capacity, and life cycle.

FPGA Control System for the Automated Test of MicroShutters

NASA Technical Reports Server (NTRS)

Lyness, Eric; Rapchun, David A.; Moseley, S. Harvey

2008-01-01

The James Webb Space Telescope, scheduled to replace the Hubble in 2013, must simultaneously observe hundreds of faint galaxies. This requirement has led to the development of a programmable transmission mask which can be adapted to admit light from an arbitrary pattern of galaxies into its spectrograph. This programmable mask will contain a large array of micro-electromechanical (MEMs) devices called MicroShutters. These microscopic shutters physically open and close like the shutter on a camera, except each shutter is microscopic in size and an array 365 by 171 is used to select the objects under spectroscopic observation at a given time, and to block the unwanted background light from other areas. NASA developed and is currently refining the exceptionally difficult process of manufacturing these shutters. This paper describes how the authors used LabVIEW FPGA and a reconfigurable I/O board to control the shutters in a test chamber and how the flexibility of the system allows us to continue to modify the control algorithms as NASA optimizes the performance of the MicroShutter arrays.

Evaluation of laser ablation crater relief by white light micro interferometer

NASA Astrophysics Data System (ADS)

Gurov, Igor; Volkov, Mikhail; Zhukova, Ekaterina; Ivanov, Nikita; Margaryants, Nikita; Potemkin, Andrey; Samokhvalov, Andrey; Shelygina, Svetlana

2017-06-01

A multi-view scanning method is suggested to assess a complicated surface relief by white light interferometer. Peculiarities of the method are demonstrated on a special object in the form of quadrangular pyramid cavity, which is formed at measurement of micro-hardness of materials using a hardness gauge. An algorithm of the joint processing of multi-view scanning results is developed that allows recovering correct relief values. Laser ablation craters were studied experimentally, and their relief was recovered using the developed method. It is shown that the multi-view scanning reduces ambiguity when determining the local depth of the laser ablation craters micro relief. Results of experimental studies of the multi-view scanning method and data processing algorithm are presented.

Surface roughness: A review of its measurement at micro-/nano-scale

NASA Astrophysics Data System (ADS)

Gong, Yuxuan; Xu, Jian; Buchanan, Relva C.

2018-01-01

The measurement of surface roughness at micro-/nano-scale is of great importance to metrological, manufacturing, engineering, and scientific applications given the critical roles of roughness in physical and chemical phenomena. The surface roughness of materials can significantly change the way of how they interact with light, phonons, molecules, and so forth, thus surface roughness ultimately determines the functionality and property of materials. In this short review, the techniques of measuring micro-/nano-scale surface roughness are discussed with special focus on the limitations and capabilities of each technique. In addition, the calculations of surface roughness and their theoretical background are discussed to offer readers a better understanding of the importance of post-measurement analysis. Recent progress on fractal analysis of surface roughness is discussed to shed light on the future efforts in surface roughness measurement.

A Study on Micro-Machining Technology for the Machining of NiTi: Five-Axis Micro-Milling and Micro Deep-Hole Drilling

NASA Astrophysics Data System (ADS)

Biermann, D.; Kahleyss, F.; Krebs, E.; Upmeier, T.

2011-07-01

Micro-sized applications are gaining more and more relevance for NiTi-based shape memory alloys (SMA). Different types of micro-machining offer unique possibilities for the manufacturing of NiTi components. The advantage of machining is the low thermal influence on the workpiece. This is important, because the phase transformation temperatures of NiTi SMAs can be changed and the components may need extensive post manufacturing. The article offers a simulation-based approach to optimize five-axis micro-milling processes with respect to the special material properties of NiTi SMA. Especially, the influence of the various tool inclination angles is considered for introducing an intelligent tool inclination optimization algorithm. Furthermore, aspects of micro deep-hole drilling of SMAs are discussed. Tools with diameters as small as 0.5 mm are used. The possible length-to-diameter ratio reaches up to 50. This process offers new possibilities in the manufacturing of microstents. The study concentrates on the influence of the cutting speed, the feed and the tool design on the tool wear and the quality of the drilled holes.

Advancing three-dimensional MEMS by complimentary laser micro manufacturing

NASA Astrophysics Data System (ADS)

Palmer, Jeremy A.; Williams, John D.; Lemp, Tom; Lehecka, Tom M.; Medina, Francisco; Wicker, Ryan B.

2006-01-01

This paper describes improvements that enable engineers to create three-dimensional MEMS in a variety of materials. It also provides a means for selectively adding three-dimensional, high aspect ratio features to pre-existing PMMA micro molds for subsequent LIGA processing. This complimentary method involves in situ construction of three-dimensional micro molds in a stand-alone configuration or directly adjacent to features formed by x-ray lithography. Three-dimensional micro molds are created by micro stereolithography (MSL), an additive rapid prototyping technology. Alternatively, three-dimensional features may be added by direct femtosecond laser micro machining. Parameters for optimal femtosecond laser micro machining of PMMA at 800 nanometers are presented. The technical discussion also includes strategies for enhancements in the context of material selection and post-process surface finish. This approach may lead to practical, cost-effective 3-D MEMS with the surface finish and throughput advantages of x-ray lithography. Accurate three-dimensional metal microstructures are demonstrated. Challenges remain in process planning for micro stereolithography and development of buried features following femtosecond laser micro machining.

Enhanced Output Power of Near-Ultraviolet Light-Emitting Diodes by p-GaN Micro-Rods

NASA Astrophysics Data System (ADS)

Wang, Dong-Sheng; Zhang, Ke-Xiong; Liang, Hong-Wei; Song, Shi-Wei; Yang, De-Chao; Shen, Ren-Sheng; Liu, Yang; Xia, Xiao-Chuan; Luo, Ying-Min; Du, Guo-Tong

2014-02-01

Near-ultraviolet (UV) InGaN/AlGaN light-emitting diodes (LEDs) are grown by low-pressure metal-organic chemical vapor deposition. The scanning electronic microscope image shows that the p-GaN micro-rods are formed above the interface of p-AlGaN/p-GaN due to the rapid growth rate of p-GaN in the vertical direction. The p-GaN micro-rods greatly increase the escape probability of photons inside the LED structure. Electroluminescence intensities of the 372 nm UV LED lamps with p-GaN micro rods are 88% higher than those of the flat surface LED samples.

Micro-incubator for bacterial biosensing applications

NASA Astrophysics Data System (ADS)

Clasen, Estine; Land, Kevin; Joubert, Trudi-Heleen

2016-02-01

The presence of Escherichia coli (E. coli ) is a commonly used indicator micro-organism to determine whether water is safe for human consumption.1 This paper discusses the design of a micro-incubator that can be applied to concentrate bacteria prior to environmental water quality screening tests. High sensitivity and rapid test time is essential and there is a great need for these tests to be implemented on-site without the use of a laboratory infrastructure. In the light of these requirements, a mobile micro-incubator was designed, manufactured and characterised. A polydimethylsiloxane (PDMS) receptacle has been designed to house the 1-5 ml cell culture sample.2 A nano-silver printed electronics micro-heater has been designed to incubate the bacterial sample, with an array of temperature sensors implemented to accurately measure the sample temperature at various locations in the cell culture well. The micro-incubator limits the incubation temperature range to 37+/-3 °C in order to ensure near optimal growth of the bacteria at all times.3 The incubation time is adjustable between 30 minutes and 9 hours with a maximum rise time of 15 minutes to reach the set-point temperature. The surface area of the printed nano silver heating element is 500 mm2. Electrical and COMSOL Multiphysics simulations are included in order to give insight on micro-incubator temperature control. The design and characterization of this micro-incubator allows for further research in biosensing applications.

[A micro-silicon multi-slit spectrophotometer based on MEMS technology].

PubMed

Hao, Peng; Wu, Yi-Hui; Zhang, Ping; Liu, Yong-Shun; Zhang, Ke; Li, Hai-Wen

2009-06-01

A new mini-spectrophotometer was developed by adopting micro-silicon slit and pixel segmentation technology, and this spectrophotometer used photoelectron diode array as the detector by the back-dividing-light way. At first, the effect of the spectral bandwidth on the tested absorbance linear correlation was analyzed. A theory for the design of spectrophotometer's slit was brought forward after discussing the relationships between spectrophotometer spectrum band width and pre-and post-slits width. Then, the integrative micro-silicon-slit, which features small volume, high precision, and thin thickness, was manufactured based on the MEMS technology. Finally, a test was carried on linear absorbance solution by this spectrophotometer. The final result showed that the correlation coefficients were larger than 0.999, which means that the new mini-spectrophotometer with micro-silicon slit pixel segmentation has an obvious linear correlation.

Wafer-level manufacturing technology of glass microlenses

NASA Astrophysics Data System (ADS)

Gossner, U.; Hoeftmann, T.; Wieland, R.; Hansch, W.

2014-08-01

In high-tech products, there is an increasing demand to integrate glass lenses into complex micro systems. Especially in the lighting industry LEDs and laser diodes used for automotive applications require encapsulated micro lenses. To enable low-cost production, manufacturing of micro lenses on wafer level base using a replication technology is a key technology. This requires accurate forming of thousands of lenses with a diameter of 1-2 mm on a 200 mm wafer compliant with mass production. The article will discuss the technical aspects of a lens manufacturing replication process and the challenges, which need to be solved: choice of an appropriate master for replication, thermally robust interlayer coating, choice of replica glass, bonding and separation procedure. A promising approach for the master substrate material is based on a lens structured high-quality glass wafer with high melting point covered by a coating layer of amorphous silicon or germanium. This layer serves as an interlayer for the glass bonding process. Low pressure chemical vapor deposition and plasma enhanced chemical vapor deposition processes allow a deposition of layer coatings with different hydrogen and doping content influencing their chemical and physical behavior. A time reduced molding process using a float glass enables the formation of high quality lenses while preserving the recyclability of the mother substrate. The challenge is the separation of the replica from the master mold. An overview of chemical methods based on optimized etching of coating layer through small channels will be given and the impact of glass etching on surface roughness is discussed.

Micro Autonomous Systems Research: Systems Engineering Processes for Micro Autonomous Systems

DTIC Science & Technology

2016-11-01

product family design and reconfigurable system design with recent developments in the fields of automated manufacturing and micro-autonomous...mapped to design parameters. These mappings are the mechanism by which physical product designs are formulated. Finally, manufacture of the product ... design tools and manufacturing and testing the resulting design . The final products were inspected and flight tested so that their

All fiber cladding mode stripper with uniform heat distribution and high cladding light loss manufactured by CO2 laser ablation

NASA Astrophysics Data System (ADS)

Jebali, M. A.; Basso, E. T.

2018-02-01

Cladding mode strippers are primarily used at the end of a fiber laser cavity to remove high-power excess cladding light without inducing core loss and beam quality degradation. Conventional manufacturing methods of cladding mode strippers include acid etching, abrasive blasting or laser ablation. Manufacturing of cladding mode strippers using laser ablation consist of removing parts of the cladding by fused silica ablation with a controlled penetration and shape. We present and characterize an optimized cladding mode stripper design that increases the cladding light loss with a minimal device length and manufacturing time. This design reduces the localized heat generation by improving the heat distribution along the device. We demonstrate a cladding mode stripper written on a 400um fiber with cladding light loss of 20dB, with less than 0.02dB loss in the core and minimal heating of the fiber and coating. The manufacturing process of the designed component is fully automated and takes less than 3 minutes with a very high throughput yield.

A modular assembling platform for manufacturing of microsystems by optical tweezers

NASA Astrophysics Data System (ADS)

Ksouri, Sarah Isabelle; Aumann, Andreas; Ghadiri, Reza; Prüfer, Michael; Baer, Sebastian; Ostendorf, Andreas

2013-09-01

Due to the increased complexity in terms of materials and geometries for microsystems new assembling techniques are required. Assembling techniques from the semiconductor industry are often very specific and cannot fulfill all specifications in more complex microsystems. Therefore, holographic optical tweezers are applied to manipulate structures in micrometer range with highest flexibility and precision. As is well known non-spherical assemblies can be trapped and controlled by laser light and assembled with an additional light modulator application, where the incident laser beam is rearranged into flexible light patterns in order to generate multiple spots. The complementary building blocks are generated by a two-photon-polymerization process. The possibilities of manufacturing arbitrary microstructures and the potential of optical tweezers lead to the idea of combining manufacturing techniques with manipulation processes to "microrobotic" processes. This work presents the manipulation of generated complex microstructures with optical tools as well as a storage solution for 2PP assemblies. A sample holder has been developed for the manual feeding of 2PP building blocks. Furthermore, a modular assembling platform has been constructed for an `all-in-one' 2PP manufacturing process as a dedicated storage system. The long-term objective is the automation process of feeding and storage of several different 2PP micro-assemblies to realize an automated assembly process.

Fully utilizing high power diode lasers by synergizing diode laser light sources and beam shaping micro-optics

NASA Astrophysics Data System (ADS)

Fan, Yingmin; Wang, Jingwei; Cai, Lei; Mitra, Thomas; Hauschild, Dirk; Zah, Chung-En; Liu, Xingsheng

2018-02-01

High power diode lasers (HPDLs) offer the highest wall-plug efficiency, highest specific power (power-to-weight ratio), arguably the lowest cost and highest reliability among all laser types. However, the poor beam quality of commercially HPDLs is the main bottleneck limiting their direct applications requiring high brightness at least in one dimension. In order to expand the applications of HPDLs, beam shaping and optical design are essential. In this work, we report the recent progresses on maximizing applications of HPDLs by synergizing diode laser light source and beam shaping micro-optics. Successful examples of matching of diode laser light sources and beam shaping micro-optics driving new applications are presented.

Optical sectioning microscopes with no moving parts using a micro-stripe array light emitting diode.

PubMed

Poher, V; Zhang, H X; Kennedy, G T; Griffin, C; Oddos, S; Gu, E; Elson, D S; Girkin, M; French, P M W; Dawson, M D; Neil, M A

2007-09-03

We describe an optical sectioning microscopy system with no moving parts based on a micro-structured stripe-array light emitting diode (LED). By projecting arbitrary line or grid patterns onto the object, we are able to implement a variety of optical sectioning microscopy techniques such as grid-projection structured illumination and line scanning confocal microscopy, switching from one imaging technique to another without modifying the microscope setup. The micro-structured LED and driver are detailed and depth discrimination capabilities are measured and calculated.

Light-focusing human micro-lenses generated from pluripotent stem cells model lens development and drug-induced cataract in vitro

PubMed Central

Murphy, Patricia; Kabir, Md Humayun; Srivastava, Tarini; Mason, Michele E.; Dewi, Chitra U.; Lim, Seakcheng; Yang, Andrian; Djordjevic, Djordje; Killingsworth, Murray C.; Ho, Joshua W. K.; Harman, David G.

2018-01-01

ABSTRACT Cataracts cause vision loss and blindness by impairing the ability of the ocular lens to focus light onto the retina. Various cataract risk factors have been identified, including drug treatments, age, smoking and diabetes. However, the molecular events responsible for these different forms of cataract are ill-defined, and the advent of modern cataract surgery in the 1960s virtually eliminated access to human lenses for research. Here, we demonstrate large-scale production of light-focusing human micro-lenses from spheroidal masses of human lens epithelial cells purified from differentiating pluripotent stem cells. The purified lens cells and micro-lenses display similar morphology, cellular arrangement, mRNA expression and protein expression to human lens cells and lenses. Exposing the micro-lenses to the emergent cystic fibrosis drug Vx-770 reduces micro-lens transparency and focusing ability. These human micro-lenses provide a powerful and large-scale platform for defining molecular disease mechanisms caused by cataract risk factors, for anti-cataract drug screening and for clinically relevant toxicity assays. PMID:29217756

Light-focusing human micro-lenses generated from pluripotent stem cells model lens development and drug-induced cataract in vitro.

PubMed

Murphy, Patricia; Kabir, Md Humayun; Srivastava, Tarini; Mason, Michele E; Dewi, Chitra U; Lim, Seakcheng; Yang, Andrian; Djordjevic, Djordje; Killingsworth, Murray C; Ho, Joshua W K; Harman, David G; O'Connor, Michael D

2018-01-09

Cataracts cause vision loss and blindness by impairing the ability of the ocular lens to focus light onto the retina. Various cataract risk factors have been identified, including drug treatments, age, smoking and diabetes. However, the molecular events responsible for these different forms of cataract are ill-defined, and the advent of modern cataract surgery in the 1960s virtually eliminated access to human lenses for research. Here, we demonstrate large-scale production of light-focusing human micro-lenses from spheroidal masses of human lens epithelial cells purified from differentiating pluripotent stem cells. The purified lens cells and micro-lenses display similar morphology, cellular arrangement, mRNA expression and protein expression to human lens cells and lenses. Exposing the micro-lenses to the emergent cystic fibrosis drug Vx-770 reduces micro-lens transparency and focusing ability. These human micro-lenses provide a powerful and large-scale platform for defining molecular disease mechanisms caused by cataract risk factors, for anti-cataract drug screening and for clinically relevant toxicity assays. © 2018. Published by The Company of Biologists Ltd.

To enhance light extraction of OLED devices by multi-optic layers including a micro lens array

NASA Astrophysics Data System (ADS)

Chiu, Chuang-Hung; Chien, Chao-Heng; Kuo, Yu-Xaong; Lee, Jen-Chi

2014-10-01

In recent years, OLED has advantages including that larger light area, thinner thickness, excellent light uniformity, and can be as a flexible light source. Many display panel and lighting have been started to use the OLED due to OLED without back light system, thus how to make and employ light extracting layer could be important issue to enhance OLED brightness. The purpose of this study is to enhance the light extraction efficiency and light emitting area of OLED, so the micro lens array and the prism reflection layer were provided to enhance the surface light extracting efficiency of OLD. Finally the prism layer and diffusing layer were used to increase the uniformity of emitting area of OLED, which the efficiency of 31% increasing to compare with the OLED without light extracting film.

Fully solution-processed organic light-emitting electrochemical cells (OLEC) with inkjet-printed micro-lenses for disposable lab-on-chip applications at ambient conditions

NASA Astrophysics Data System (ADS)

Shu, Zhe; Pabst, Oliver; Beckert, Erik; Eberhardt, Ramona; Tünnermann, Andreas

2016-02-01

Microfluidic lab-on-chip devices can be used for chemical and biological analyses such as DNA tests or environmental monitoring. Such devices integrate most of the basic functionalities needed for scientific analysis on a microfluidic chip. When using such devices, cost and space-intensive lab equipment is no longer necessary. However, in order to make a monolithic and cost-efficient/disposable microfluidic sensing device, direct integration of the excitation light source for fluorescent sensing is often required. To achieve this, we introduce a fully solution processable deviation of OLEDs, organic light-emitting electrochemical cells (OLECs), as a low-cost excitation light source for a disposable microfluidic sensing platform. By mixing metal ions and a solid electrolyte with light-emitting polymers as active materials, an in-situ doping and in-situ PN-junction can be generated within a three layer sandwich device. Thanks to this doping effect, work function adaptation is not necessary and air-stable electrode can be used. An ambient manufacturing process for fully solution-processed OLECs is presented, which consist of a spin-coated blue light-emitting polymer plus dopants on an ITO cathode and an inkjet-printed PEDOT:PSS transparent top anode. A fully transparent blue OLEC is able to obtain light intensity > 2500 cd/m2 under pulsed driving mode and maintain stable after 1000 cycles, which fulfils requirements for simple fluorescent on-chip sensing applications. However, because of the large refractive index difference between substrates and air, about 80% of emitted light is trapped inside the device. Therefore, inkjet printed micro-lenses on the rear side are introduced here to further increase light-emitting brightness.

Method of Manufacturing Micro-Disperse Particles of Sodium Borohydride

DOEpatents

Kravitz, Stanley H.; Hecht, Andrew M.; Sylwester. Alan P.; Bell, Nelson S.

2008-09-23

A compact solid source of hydrogen gas, where the gas is generated by contacting water with micro-disperse particles of sodium borohydride in the presence of a catalyst, such as cobalt or ruthenium. The micro-disperse particles can have a substantially uniform diameter of 1-10 microns, and preferably about 3-5 microns. Ruthenium or cobalt catalytic nanoparticles can be incorporated in the micro-disperse particles of sodium borohydride, which allows a rapid and complete reaction to occur without the problems associated with caking and scaling of the surface by the reactant product sodium metaborate. A closed loop water management system can be used to recycle wastewater from a PEM fuel cell to supply water for reacting with the micro-disperse particles of sodium borohydride in a compact hydrogen gas generator. Capillary forces can wick water from a water reservoir into a packed bed of micro-disperse fuel particles, eliminating the need for using an active pump.

Open-source micro-tensile testers via additive manufacturing for the mechanical characterization of thin films and papers

PubMed Central

Scheftic, Charlie M.; Brinson, L. Catherine

2018-01-01

The cost of specialized scientific equipment can be high and with limited funding resources, researchers and students are often unable to access or purchase the ideal equipment for their projects. In the fields of materials science and mechanical engineering, fundamental equipment such as tensile testing devices can cost tens to hundreds of thousands of dollars. While a research lab often has access to a large-scale testing machine suitable for conventional samples, loading devices for meso- and micro-scale samples for in-situ testing with the myriad of microscopy tools are often hard to source and cost prohibitive. Open-source software has allowed for great strides in the reduction of costs associated with software development and open-source hardware and additive manufacturing have the potential to similarly reduce the costs of scientific equipment and increase the accessibility of scientific research. To investigate the feasibility of open-source hardware, a micro-tensile tester was designed with a freely accessible computer-aided design package and manufactured with a desktop 3D-printer and off-the-shelf components. To our knowledge this is one of the first demonstrations of a tensile tester with additively manufactured components for scientific research. The capabilities of the tensile tester were demonstrated by investigating the mechanical properties of Graphene Oxide (GO) paper and thin films. A 3D printed tensile tester was successfully used in conjunction with an atomic force microscope to provide one of the first quantitative measurements of GO thin film buckling under compression. The tensile tester was also used in conjunction with an atomic force microscope to observe the change in surface topology of a GO paper in response to increasing tensile strain. No significant change in surface topology was observed in contrast to prior hypotheses from the literature. Based on this result obtained with the new open source tensile stage we propose an

Open-source micro-tensile testers via additive manufacturing for the mechanical characterization of thin films and papers.

PubMed

Nandy, Krishanu; Collinson, David W; Scheftic, Charlie M; Brinson, L Catherine

2018-01-01

The cost of specialized scientific equipment can be high and with limited funding resources, researchers and students are often unable to access or purchase the ideal equipment for their projects. In the fields of materials science and mechanical engineering, fundamental equipment such as tensile testing devices can cost tens to hundreds of thousands of dollars. While a research lab often has access to a large-scale testing machine suitable for conventional samples, loading devices for meso- and micro-scale samples for in-situ testing with the myriad of microscopy tools are often hard to source and cost prohibitive. Open-source software has allowed for great strides in the reduction of costs associated with software development and open-source hardware and additive manufacturing have the potential to similarly reduce the costs of scientific equipment and increase the accessibility of scientific research. To investigate the feasibility of open-source hardware, a micro-tensile tester was designed with a freely accessible computer-aided design package and manufactured with a desktop 3D-printer and off-the-shelf components. To our knowledge this is one of the first demonstrations of a tensile tester with additively manufactured components for scientific research. The capabilities of the tensile tester were demonstrated by investigating the mechanical properties of Graphene Oxide (GO) paper and thin films. A 3D printed tensile tester was successfully used in conjunction with an atomic force microscope to provide one of the first quantitative measurements of GO thin film buckling under compression. The tensile tester was also used in conjunction with an atomic force microscope to observe the change in surface topology of a GO paper in response to increasing tensile strain. No significant change in surface topology was observed in contrast to prior hypotheses from the literature. Based on this result obtained with the new open source tensile stage we propose an

Light transmittance and micro-mechanical properties of bulk fill vs. conventional resin based composites.

PubMed

Bucuta, Stefan; Ilie, Nicoleta

2014-11-01

The aim of this study was to quantify the blue light that passes through different incremental thicknesses of bulk fill in comparison to conventional resin-based composites (RBCs) and to relate it to the induced mechanical properties. Seven bulk fill, five nanohybrid and two flowable RBCs were analysed. Specimens (n = 5) of three incremental thicknesses (2, 4 and 6 mm) were cured from the top for 20 s, while at the bottom, a spectrometer monitored in real time the transmitted irradiance. Micro-mechanical properties (Vickers hardness, HV, and indentation modulus, E) were measured at the top and bottom after 24 h of storage in distilled water at 37 °C. Electron microscope images were taken for assessing the filler distribution and size. Bulk fill RBCs (except SonicFill) were more translucent than conventional RBCs. Low-viscosity bulk fill materials showed the lowest mechanical properties. HV depends highly on the following parameters: material (ηp (2) = 0.952), incremental thickness (0.826), filler volume (0.747), filler weight (0.746) and transmitted irradiance (0.491). The bottom-to-top HV ratio (HVbt) was higher than 80 % in all materials in 2- and 4-mm increments (except for Premise), whereas in 6-mm increments, this is valid only in four bulk fill materials (Venus Bulk Fill, SDR, x-tra fil, Tetric EvoCeram Bulk Fill). The depth of cure is dependent on the RBC's translucency. Low-viscosity bulk fill RBCs have lower mechanical properties than all other types of analysed materials. All bulk fill RBCs (except SonicFill) are more translucent for blue light than conventional RBCs. Although bulk fill RBCs are generally more translucent, the practitioner has to follow the manufacturer's recommendations on curing technique and maximum incremental thickness.

Investigation of Very Fast Light Detectors: Silicon Photomultiplier and Micro PMT for a Cosmic Ray Array

NASA Astrophysics Data System (ADS)

Cervantes, Omar; Reyes, Liliana; Hooks, Tyler; Perez, Luis; Ritt, Stefan

2016-03-01

To construct a cosmic detector array using 4 scintillation detectors, we investigated 2 recent light sensor technologies from Hamamatsu, as possible readout detectors. First, we investigated several homemade versions of the multipixel photon counter (MPPC) light sensors. These detectors were either biased with internal or external high voltage power supplies. We made extensive measurements to confirm for the coincidence of the MPPC devices. Each sensor is coupled to a wavelength shifting fiber (WSF) that is embedded along a plastic scintillator sheet (30cmx60cmx1/4''). Using energetic cosmic rays, we evaluated several of these homemade detector modules placed above one another in a light proof enclosure. Next, we assembled 2 miniaturized micro photomultiplier (micro PMT), a device recently marketed by Hamamatsu. These sensors showed very fast response times. With 3 WSF embedded in scintillator sheets, we performed coincidence experiments. The detector waveforms were captured using the 5GS/sec domino ring sampler, the DRS4 and our workflow using the CERN PAW package and data analysis results would be presented. Title V Grant.

Development of ultra-precision micro-cavity measurement technique in HIT-UOI

NASA Astrophysics Data System (ADS)

Cui, Jiwen; Li, Lei; Tan, Jiubin

2010-08-01

Micro cavities with high aspect ratio are widely used in different fields including aerospace and defense industries with the development of manufacturing technology. So how to measure the dimension of these cavities has become one of the major research subjects in the field of measurement and instrument. This paper describes some activities of the precision micro cavity measurement technique in Center of Ultra-precision Optoelectronic Instrument (UOI), Harbin Institute of Technology (HIT). The key issue of micro cavity measurement in UOI is called touch-trigger measurement method. The first scheme is double optical fiber coupling, in which light coming from the incident optical fiber is transmitted in the reversal direction via the optical fiber coupling into the effluent optical fiber, the lateral displacement of the touch-trigger sensor is transformed into the deflexion of light coming out from the effluent optical fiber, and the deflexion is transformed into an image signal by the object lens and CCD capturing system. And the second scheme is micro focal-length collimation, in which a fiber stem with a ball mounted on its end is used as a probe and a small segment of it is used as a cylindrical lens to collimate a point light source and image it to a camera, the deflection of the fiber stem can be inferred from the change in image acquired by the camera with ultrahigh displacement sensitivity. Experiments for these activities will be given with a focus on the measurement results and repeatability uncertainty.

Effective micro-spray cooling for light-emitting diode with graphene nanoporous layers

NASA Astrophysics Data System (ADS)

Keong Lay, Kok; Yew Cheong, Brian Mun; Li Tong, Wei; Tan, Ming Kwang; Hung, Yew Mun

2017-04-01

A graphene nanoplatelet (GNP) coating is utilized as a functionalized surface in enhancing the evaporation rate of micro-spray cooling for light-emitting diodes (LEDs). In micro-spray cooling, water is atomized into micro-sized droplets to reduce the surface energy and to increase the surface area for evaporation. The GNP coating facilitates the effective filmwise evaporation through the attribute of fast water permeation. The oxygenated functional groups of GNPs provide the driving force that initiates the intercalation of water molecules through the carbon nanostructure. The water molecules slip through the frictionless passages between the hydrophobic carbon walls, resulting an effective filmwise evaporation. The enhancement of evaporation leads to an enormous temperature reduction of 61.3 °C. The performance of the LED is greatly enhanced: a maximum increase in illuminance of 25% and an extension of power rating from 9 W to 12 W can be achieved. With the application of GNP coating, the high-temperature region is eliminated while maintaining the LED surface temperature for optimal operation. This study paves the way for employing the effective hybrid spray-evaporation-nanostructure technique in the development of a compact, low-power-consumption cooling system.

A novel carbon tipped single micro-optrode for combined optogenetics and electrophysiology

PubMed Central

Vizvári, Attila D.; Bali, Zsolt K.; Márki, Balázs; Nagy, Lili V.; Kónya, Zoltán; Madarász, Dániel; Henn-Mike, Nóra; Varga, Csaba; Hernádi, István

2018-01-01

Optical microelectrodes (optrodes) are used in neuroscience to transmit light into the brain of a genetically modified animal to evoke and record electrical activity from light-sensitive neurons. Our novel micro-optrode solution integrates a light-transmitting 125 micrometer optical fiber and a 9 micrometer carbon monofilament to form an electrical lead element, which is contained in a borosilicate glass sheathing coaxial arrangement ending with a micrometer-sized carbon tip. This novel unit design is stiff and slender enough to be used for targeting deep brain areas, and may cause less tissue damage compared with previous models. The center-positioned carbon fiber is less prone to light-induced artifacts than side-lit metal microelectrodes previously presented. The carbon tip is capable of not only recording electrical signals of neuronal origin but can also provide valuable surface area for electron transfer, which is essential in electrochemical (voltammetry, amperometry) or microbiosensor applications. We present details of design and manufacture as well as operational examples of the newly developed single micro-optrode, which includes assessments of 1) carbon tip length–impedance relationship, 2) light transmission capabilities, 3) photoelectric artifacts in carbon fibers, 4) responses to dopamine using fast-scan cyclic voltammetry in vivo, and 5) optogenetic stimulation and spike or local field potential recording from the rat brain transfected with channelrhodopsin-2. With this work, we demonstrate that our novel carbon tipped single micro-optrode may open up new avenues for use in optogenetic stimulation when needing to be combined with extracellular recording, electrochemical, or microbiosensor measurements performed on a millisecond basis. PMID:29513711

Application of dynamic light scattering for studying the evolution of micro- and nano-droplets

NASA Astrophysics Data System (ADS)

Derkachov, G.; Jakubczyk, D.; Kolwas, K.; Shopa, Y.; Woźniak, M.; Wojciechowski, T.

2018-01-01

The dynamic light scattering (DLS) technique was used for studying the processes of aggregation of spherical SiO2 particles in various diethylene glycol (DEG) suspensions. The suspensions were studied in a cuvette, in a millimeter-sized droplet and in a micrometer-sized droplet. For the first time DLS signals for droplets of picolitre volume, levitated in an electrodynamic quadrupole trap, were obtained. It is shown that the correlation analysis of light scattered from a micro-droplet allows monitoring the changes of its internal structure, as well as its motions: trap-constricted Brownian motions and random rotations.

Driving platform for OLED lighting investigations

NASA Astrophysics Data System (ADS)

Vogel, Uwe; Elgner, Andreas; Kreye, Daniel; Amelung, Jörg; Scholles, Michael

2006-08-01

OLED technology may be excellently suitable for lighting applications by combining high efficiency, cost effective manufacturing and the use of low cost materials. Certain issues remain to be solved so far, including OLED brightness, color, lifetime, large area uniformity and encapsulation. Another aspect, that might be capable in addressing some of the mentioned issues, is OLED lighting electrical driving. We report on the design of a driving platform for OLED lighting test panels or substrates. It is intended for being a test environment for lighting substrates as well as demonstration/presentation environment. It is based on a 128-channel passive-matrix driver/controller ASIC OC2. Its key component is an MSP430-compatible 16-bit micro-controller core including embedded Flash memory (program), EEPROM (parameter), and RAM (data memory). A significant feature of the device is an electronic approach for improving the lifetime/uniformity behavior of connected OLED. The embedded micro-controller is the key to the high versatility of OC2, since by firmware modification it can be adapted to various applications and conditions. Here its application for an OLED lighting driving platform is presented. Major features of this platform are PC-control mode (via USB interface), stand-alone mode (no external control necessary, just power supply), on-board OLED panel parameter storage, flat geometry of OLED lighting panel carrier (board), AC and DC driving regimes, adjustable reverse voltage, dedicated user SW (PC/Windows-based), sub-tile patterning and single sub-tile control, combination of multiple channels for increasing driving current. This publication contains results of the project "High Brightness OLEDs for ICT & Next Generation Lighting Applications" (OLLA), funded by the European Commission.

Strong Evidence of Variable Micro-meteor Flux from Apollo 17 Samples Obtained at Shorty Crater and on the Light Mantle Avalanche at Taurus-Littrow

NASA Astrophysics Data System (ADS)

Schmitt, H. H.; Petro, N. E.

2017-12-01

Light-gray regolith overlying the orange and black pyroclastic ash (Schmitt, 2017) at Shorty Crater protected the ash from incorporation into surrounding basaltic regolith for 3.5 billion years (Tera and Wasserburg, 1976; Saito and Alexander, 1979). Inspection of LROC images indicate this regolith probably came from a 350 m diameter, degraded impact crater (Fitzgibbon Crater), about 1 km NNE of Shorty. This regolith was derived largely from basalt and spread over the ash deposit about 24 Myr (Eugster, et al., 1979, corrected for post-Shorty exposure) after the last ash eruption. Maturity indexes for light gray regolith samples 74441 and 74461 are about 8 (Morris, 1978) and agglutinate concentrations are 8% and 7.7% (Heiken and McKay, 1974), respectively. These values are inconsistent with the exposure and cycling of the light-gray regolith during 3.5 billion years in the lunar surface impact environment (i.e., the time between ash deposition and the light mantle avalanche). If agglutinate content and Is/FeO indexes largely reflect the cumulative effect of micro-meteor impacts, as generally concluded, the light-gray regolith formed in an environment with significantly less micro-meteor flux than that which has prevailed more recently. 14-18% of fragile, ropy glass in the light-gray regolith, as compared with <1% in presently exposed Taurus-Littrow regoliths, also is consistent with low micro-meteor flux during development. The high recent micro-meteor flux appears to have existed for at least for the last 75 million years (Schmitt, et al., 2017), the estimated time using LROC-based crater frequency analysis (van der Bogert, et al., 2012) since the light mantle avalanche of South Massif regolith covered the light-gray regolith. New regolith on the light mantle appears to be developing a higher concentration of agglutinates and a higher maturity index relative to regolith in deeper portions of the unit. Light mantle avalanche samples 73141 (subsurface) and 73121 (near

Verify Module for Reporting A/C and Off-Cycle GHG Credits for Light-Duty Vehicle and Truck Manufacturers

EPA Pesticide Factsheets

This EPA presentation provides information on using the new Verify module, streamlining the process required to electronically submit annual reporting of air conditioning (A/C) and off-cycle GHG credits for light duty manufacturers.

Manufacturing polymer light emitting diode with high luminance efficiency by solution process

NASA Astrophysics Data System (ADS)

Kim, Miyoung; Jo, SongJin; Yang, Ho Chang; Yoon, Dang Mo; Kwon, Jae-Taek; Lee, Seung-Hyun; Choi, Ju Hwan; Lee, Bum-Joo; Shin, Jin-Koog

2012-06-01

While investigating polymer light emitting diodes (polymer-LEDs) fabricated by solution process, surface roughness influences electro-optical (E-O) characteristics. We expect that E-O characteristics such as luminance and power efficiency related to surface roughness and layer thickness of emitting layer with poly-9-Vinylcarbazole. In this study, we fabricated polymer organic light emitting diodes by solution process which guarantees easy, eco-friendly and low cost manufacturing for flexible display applications. In order to obtain high luminescence efficiency, E-O characteristics of these devices by varying parameters for printing process have been investigated. Therefore, we optimized process condition for polymer-LEDs by adjusting annealing temperatures of emission, thickness of emission layer showing efficiency (10.8 cd/A) at 10 mA/cm2. We also checked wavelength dependent electroluminescence spectrum in order to find the correlation between the variation of efficiency and the thickness of the layer.

Micro-X-ray fluorescence spectrometer with x-ray single bounce metallic capillary optics for light element analysis (Conference Presentation)

NASA Astrophysics Data System (ADS)

Mroczka, Robert; Żukociński, Grzegorz; Łopucki, Rafał

2017-05-01

In the last 20 years, , due to the rapid development of X-ray optics, micro X-ray fluorescence spectrometry (micro-XRF) has become a powerful tool to determine the spatial distribution of major, minor, and trace elements within a sample. Micro-X-ray fluorescence (micro-XRF) spectrometers for light element analysis (6 <= Z <= 14) using glass polycapillary optics are usually designed and applied to confocal geometry. Two such X-ray optics systems are used in this setup. The first one focuses the primary beam on the sample; the second restricts the field of view of the detector. In order to be able to analyze a wider range of elements especialy with (6 <= Z <= 14), both sample and detector are under vacuum. Depth resolution varies between 100 μm at 1 keV fluorescence energy (Na-Kα) and 30 μm for 17.5 keV (Mo-Kα) [1,2]. In order to improve resolution at energies below 9 keV, our group designed similar spectrometer (in cooperation with PREVAC) but instead of primary polycapillary optics we applied single bounce metallic capillaries optics , designed and manufactured in our Laboratory. The vacuum chumber is currently under construction and is expected to be fully operational in September this year. Single bounce gold capillaries with elliptic internal shape have recently been redesigned and developed in our Laboratory. Surface roughness was reduced up to 0.5 nm and slope error to 0.3 mrad. For these capillaries an expected depth resolution varies from 3 μm (1 keV) and 10 µm for 9 keV (Cu-Kα). The spectrometer equipped with gold capillaries offers the possibility of elemental analysis with better depth resolution than is offerred by glass polycapillaries at energies below 9 keV. Furthermore, we will compare the capabilities and limitations of this spectrometer with others, that use laboratory and/or synchrotron sources. Acknowledgments: This work was supported and co-funded by the European Union as part of the Operational Programme Development of Eastern Poland for

Waste generation and utilisation in micro-sized furniture-manufacturing enterprises in Turkey.

PubMed

Top, Y

2015-01-01

The number of small-scale businesses within most national economies is generally high, especially in developing countries. Often these businesses have a weak economic status and limited environmental awareness. The type and amount of waste produced, and the recycling methods adopted by these businesses during their operation can have negative effects on the environment. This study investigated the types of waste generated and the recycling methods adopted in micro-sized enterprises engaged in the manufacture of furniture. An assessment was also made of whether the characteristics of the enterprise had any effect on the waste recycling methods that were practised. A survey was conducted of 31 enterprises in the furniture industry in Gumushane province, Turkey, which is considered a developing economy. Surveys were undertaken via face-to-face interviews. It was found that medium-density fibreboard (MDF), and to a lesser extent, chipboard, were used in the manufacture of furniture, and two major types of waste in the form of fine dust and small fragments of board are generated during the cutting of these boards. Of the resulting composite board waste, 96.9% was used for heating homes and workplaces, where it was burnt under conditions of incomplete combustion. Enterprises were found to have adopted other methods to utilise their wastes in addition to using them as fuel. Such enterprises include those operating from a basement or first floor of a building in the cities, those continuing production throughout the year, those in need for capital and those enterprises not operating a dust-collection system. Copyright © 2014 The Author. Published by Elsevier Ltd.. All rights reserved.

Influence of Manufacturing Methods of Implant-Supported Crowns on External and Internal Marginal Fit: A Micro-CT Analysis.

PubMed

Moris, Izabela C M; Monteiro, Silas Borges; Martins, Raíssa; Ribeiro, Ricardo Faria; Gomes, Erica A

2018-01-01

To evaluate the influence of different manufacturing methods of single implant-supported metallic crowns on the internal and external marginal fit through computed microtomography. Forty external hexagon implants were divided into 4 groups ( n = 8), according to the manufacturing method: GC, conventional casting; GI, induction casting; GP, plasma casting; and GCAD, CAD/CAM machining. The crowns were attached to the implants with insertion torque of 30 N·cm. The external (vertical and horizontal) marginal fit and internal fit were assessed through computed microtomography. Internal and external marginal fit data ( μ m) were submitted to a one-way ANOVA and Tukey's test ( α = .05). Qualitative evaluation of the images was conducted by using micro-CT. The statistical analysis revealed no significant difference between the groups for vertical misfit ( P = 0.721). There was no significant difference ( P > 0.05) for the internal and horizontal marginal misfit in the groups GC, GI, and GP, but it was found for the group GCAD ( P ≤ 0.05). Qualitative analysis revealed that most of the samples of cast groups exhibited crowns underextension while the group GCAD showed overextension. The manufacturing method of the crowns influenced the accuracy of marginal fit between the prosthesis and implant. The best results were found for the crowns fabricated through CAD/CAM machining.

A Knowledge Database on Thermal Control in Manufacturing Processes

NASA Astrophysics Data System (ADS)

Hirasawa, Shigeki; Satoh, Isao

A prototype version of a knowledge database on thermal control in manufacturing processes, specifically, molding, semiconductor manufacturing, and micro-scale manufacturing has been developed. The knowledge database has search functions for technical data, evaluated benchmark data, academic papers, and patents. The database also displays trends and future roadmaps for research topics. It has quick-calculation functions for basic design. This paper summarizes present research topics and future research on thermal control in manufacturing engineering to collate the information to the knowledge database. In the molding process, the initial mold and melt temperatures are very important parameters. In addition, thermal control is related to many semiconductor processes, and the main parameter is temperature variation in wafers. Accurate in-situ temperature measurment of wafers is important. And many technologies are being developed to manufacture micro-structures. Accordingly, the knowledge database will help further advance these technologies.

Fibrous dosage forms by wet 3D-micro-patterning: process design, manufacture, and drug release rate.

PubMed

Blaesi, Aron H; Saka, Nannaji

2018-06-19

Recently, we have introduced fibrous dosage forms prepared by 3D-micro-patterning of drug-laden viscous melts. Such dosage forms enable predictable microstructures and increased drug release rates, and they can be manufactured continuously. However, melt processing is not applicable if the melting temperature of the formulation is greater than the degradation temperature of the drug or of the excipient. In this work, therefore, a continuous wet micro-patterning process that operates at ambient temperature is presented. The excipient is plasticized by a solvent and the patterned dosage form is solidified by air drying. Process models show that the micro-patterning time is the ratio of the fiber length in the dosage form and the velocity of the fiber stream. It was 1.3 minutes in the experiments, but can be reduced further. The drying time is limited by the diffusive flux of solvent through the fibers: it was about 3 minutes for the experimental conditions. Furthermore, models are developed to illustrate the effects of fiber radius, inter-fiber spacing, viscosity of the drug-excipient-solvent mixture, and drying conditions on the microstructure of the dosage form. Models and experimental results show that for a viscosity of the wet fibers of the order 10 3 Pa·s, both the patterned microstructure is well preserved and the crossed fibers are well bonded. Finally, the drug release rate by the dosage forms is experimentally determined and theoretically modeled. The results of the experiments validate the models fairly. Copyright © 2018. Published by Elsevier B.V.

Simulation of micro/nano electroporation for cell transfection

NASA Astrophysics Data System (ADS)

Zhang, Guocheng; Fan, Na; Jiang, Hai; Guo, Jian; Peng, Bei

2018-03-01

The 3D micro/nano electroporation for transfection has become a powerful biological cell research technique with the development of micro-nano manufacturing technology. The micro channels connected the cells with transfection reagents on the chip were important to the transmemnbrane potentical, which directly influences the electroporation efficiency. In this study, a two-dimensional model for electroporation of cells was designed to address the effects of channels’ sizes and number on transmembrane potential. The simulation results indicated that the transmembrane potential increased with increasing size of channels’ entrances. Moreover, compared with single channel entrance, the transmembrane potential was higher when the cells located at multiple channels entrances. These results suggest that it IS required to develop higher micro manufacturing technology to create channels as we expected size.

In situ measurement of the junction temperature of light emitting diodes using a flexible micro temperature sensor.

PubMed

Lee, Chi-Yuan; Su, Ay; Liu, Yin-Chieh; Fan, Wei-Yuan; Hsieh, Wei-Jung

2009-01-01

This investigation aimed to fabricate a flexible micro resistive temperature sensor to measure the junction temperature of a light emitting diode (LED). The junction temperature is typically measured using a thermal resistance measurement approach. This approach is limited in that no standard regulates the timing of data capture. This work presents a micro temperature sensor that can measure temperature stably and continuously, and has the advantages of being lightweight and able to monitor junction temperatures in real time. Micro-electro-mechanical-systems (MEMS) technologies are employed to minimize the size of a temperature sensor that is constructed on a stainless steel foil substrate (SS-304 with 30 μm thickness). A flexible micro resistive temperature sensor can be fixed between the LED chip and the frame. The junction temperature of the LED can be measured from the linear relationship between the temperature and the resistance. The sensitivity of the micro temperature sensor is 0.059 ± 0.004 Ω/°C. The temperature of the commercial CREE(®) EZ1000 chip is 119.97 °C when it is thermally stable, as measured using the micro temperature sensor; however, it was 126.9 °C, when measured by thermal resistance measurement. The micro temperature sensor can be used to replace thermal resistance measurement and performs reliably.

Diffractive micro-optical element with nonpoint response

NASA Astrophysics Data System (ADS)

Soifer, Victor A.; Golub, Michael A.

1993-01-01

Common-use diffractive lenses have microrelief zones in the form of simple rings that provide only an optical power but do not contain any image information. They have a point-image response under point-source illumination. We must use a more complicated non-point response to focus a light beam into different light marks, letter-type images as well as for optical pattern recognition. The current presentation describes computer generation of diffractive micro- optical elements with complicated curvilinear zones of a regular piecewise-smooth structure and grey-level or staircase phase microrelief. The manufacture of non-point response elements uses the steps of phase-transfer calculation and orthogonal-scan masks generation or lithographic glass etching. Ray-tracing method is shown to be applicable in this task. Several working samples of focusing optical elements generated by computer and photolithography are presented. Using the experimental results we discuss here such applications as laser branding.

Micro and nano-structured green gallium indium nitride/gallium nitride light-emitting diodes

NASA Astrophysics Data System (ADS)

Stark, Christoph J. M.

Light-emitting diodes (LEDs) are commonly designed and studied based on bulk material properties. In this thesis different approaches based on patterns in the nano and micrometer length scale range are used to tackle low efficiency in the green spectral region, which is known as “green gap”. Since light generation and extraction are governed by microscopic processes, it is instructive to study LEDs with lateral mesa sizes scaled to the nanometer range. Besides the well-known case of the quantum size effect along the growth direction, a continuous lateral scaling could reveal the mechanisms behind the purported absence of a green gap in nanowire LEDs and the role of their extraction enhancement. Furthermore the possibility to modulate strain and piezoelectric polarization by post growth patterning is of practical interest, because the internal electric fields in conventional wurtzite GaN LEDs cause performance problems. A possible alternative is cubic phase GaN, which is free of built-in polarization fields. LEDs on cubic GaN could show the link between strong polarization fields and efficiency roll-off at high current densities, also known as droop. An additional problem for all nitride-based LEDs is efficient light extraction. For a planar GaN LED only roughly 8% of the generated light can be extracted. Novel lightextraction structures with extraction-favoring geometry can yield significant increase in light output power. To investigate the effect of scaling the mesa dimension, micro and nano-sized LED arrays of variable structure size were fabricated. The nano-LEDs were patterned by electron beam lithography and dry etching. They contained up to 100 parallel nano-stripe LEDs connected to one common contact area. The mesa width was varied over 1 μm, 200 nm, and 50 nm. These LEDs were characterized electrically and optically, and the peak emission wavelength was found to depend on the lateral structure size. An electroluminescence (EL) wavelength shift of 3 nm

And There Was Light: Prospects for the Creation of Micro- and Nanostructures through Maskless Photolithography.

PubMed

Rühe, J

2017-09-26

In photolithographic processes, the light inducing the photochemical reactions is confined to a small volume, which enables direct writing of micro- and nanoscale features onto solid surfaces without the need of a predefined photomask. The direct writing process can be used to generate topographic patterns through photopolymerization or photo-cross-linking or can be employed to use light to generate chemical patterns on the surface with high spatial control, which would make such processes attractive for bioapplications. The prospects of maskless photolithography technologies with a focus on two-photon lithography and scanning-probe-based photochemical processes based on scanning near-field optical microscopy or beam pen lithography are discussed.

Utility of Big Area Additive Manufacturing (BAAM) For The Rapid Manufacture of Customized Electric Vehicles

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

Love, Lonnie J.

This Oak Ridge National Laboratory (ORNL) Manufacturing Development Facility (MDF) technical collaboration project was conducted in two phases as a CRADA with Local Motors Inc. Phase 1 was previously reported as Advanced Manufacturing of Complex Cyber Mechanical Devices through Community Engagement and Micro-manufacturing and demonstrated the integration of components onto a prototype body part for a vehicle. Phase 2 was reported as Utility of Big Area Additive Manufacturing (BAAM) for the Rapid Manufacture of Customized Electric Vehicles and demonstrated the high profile live printing of an all-electric vehicle using ONRL s Big Area Additive Manufacturing (BAAM) technology. This demonstration generatedmore » considerable national attention and successfully demonstrated the capabilities of the BAAM system as developed by ORNL and Cincinnati, Inc. and the feasibility of additive manufacturing of a full scale electric vehicle as envisioned by the CRADA partner Local Motors, Inc.« less

Development of a real-time reflectance and transmittance monitoring system for the manufacturing of metaldielectric light absorbers

NASA Astrophysics Data System (ADS)

Badoil, Bruno; Cathelinaud, Michel; Lemarchand, Fabien; Lemarquis, Frédéric; Lequime, Michel

2017-11-01

Metal-dielectric light absorbers are of great interest for suppressing stray light in optical systems. Such coatings can give an absorption level greater than 99.9% over a broad spectral range provided that the complex refractive index of metallic films is accurately known. For this purpose we developed a new real-time monitoring system that allows to measure in situ both reflectance and transmittance of the coating during manufacturing in the deposition chamber. This paper describes the system design and its characteristics and gives some preliminary results concerning metallic thin film characterizations.

Method of Manufacturing a Light Emitting, Photovoltaic or Other Electronic Apparatus and System

NASA Technical Reports Server (NTRS)

Blanchard, Richard A. (Inventor); Lewandowski, Mark Allan (Inventor); Frazier, Donald Odell (Inventor); Ray, William Johnstone (Inventor); Fuller, Kirk A. (Inventor); Lowenthal, Mark David (Inventor); Shotton, Neil O. (Inventor)

2014-01-01

The present invention provides a method of manufacturing an electronic apparatus, such as a lighting device having light emitting diodes (LEDs) or a power generating device having photovoltaic diodes. The exemplary method includes depositing a first conductive medium within a plurality of channels of a base to form a plurality of first conductors; depositing within the plurality of channels a plurality of semiconductor substrate particles suspended in a carrier medium; forming an ohmic contact between each semiconductor substrate particle and a first conductor; converting the semiconductor substrate particles into a plurality of semiconductor diodes; depositing a second conductive medium to form a plurality of second conductors coupled to the plurality of semiconductor diodes; and depositing or attaching a plurality of lenses suspended in a first polymer over the plurality of diodes. In various embodiments, the depositing, forming, coupling and converting steps are performed by or through a printing process.

Method of Manufacturing a Light Emitting, Photovoltaic or Other Electronic Apparatus and System

NASA Technical Reports Server (NTRS)

Lowenthal, Mark D. (Inventor); Shotton, Neil O. (Inventor); Lewandowski, Mark Allan (Inventor); Frazier, Donald Odell (Inventor); Ray, William Johnstone (Inventor); Blanchard, Richard A. (Inventor); Fuller, Kirk A. (Inventor)

2013-01-01

The present invention provides a method of manufacturing an electronic apparatus, such as a lighting device having light emitting diodes (LEDs) or a power generating device having photovoltaic diodes. The exemplary method includes forming at least one first conductor coupled to a base; coupling a plurality of substrate particles to the at least one first conductor; converting the plurality of substrate particles into a plurality of diodes; forming at least one second conductor coupled to the plurality of spherical diodes; and depositing or attaching a plurality of substantially spherical lenses suspended in a first polymer, with the lenses and the suspending polymer having different indices of refraction. In some embodiments, the lenses and diodes have a ratio of mean diameters or lengths between about 10:1 and 2:1. In various embodiments, the forming, coupling and converting steps are performed by or through a printing process.

Method of manufacturing a light emitting, photovoltaic or other electronic apparatus and system

NASA Technical Reports Server (NTRS)

Fuller, Kirk A. (Inventor); Frazier, Donald Odell (Inventor); Blanchard, Richard A. (Inventor); Lowenthal, Mark D. (Inventor); Lewandowski, Mark Allan (Inventor); Ray, William Johnstone (Inventor); Shotton, Neil O. (Inventor)

2012-01-01

The present invention provides a method of manufacturing an electronic apparatus, such as a lighting device having light emitting diodes (LEDs) or a power generating device having photovoltaic diodes. The exemplary method includes depositing a first conductive medium within a plurality of channels of a base to form a plurality of first conductors; depositing within the plurality of channels a plurality of semiconductor substrate particles suspended in a carrier medium; forming an ohmic contact between each semiconductor substrate particle and a first conductor; converting the semiconductor substrate particles into a plurality of semiconductor diodes; depositing a second conductive medium to form a plurality of second conductors coupled to the plurality of semiconductor diodes; and depositing or attaching a plurality of lenses suspended in a first polymer over the plurality of diodes. In various embodiments, the depositing, forming, coupling and converting steps are performed by or through a printing process.

Method of Manufacturing a Light Emitting, Photovoltaic or Other Electronic Apparatus and System

NASA Technical Reports Server (NTRS)

Blanchard, Richard A. (Inventor); Fuller, Kirk A. (Inventor); Ray, William Johnstone (Inventor); Shotton, Neil O. (Inventor); Frazier, Donald Odell (Inventor); Lowenthal, Mark D. (Inventor); Lewandowski, Mark Allan (Inventor)

2013-01-01

The present invention provides a method of manufacturing an electronic apparatus, such as a lighting device having light emitting diodes (LEDs) or a power generating device having photovoltaic diodes. The exemplary method includes forming at least one first conductor coupled to a base; coupling a plurality of substantially spherical substrate particles to the at least one first conductor; converting the substrate particles into a plurality of substantially spherical diodes; forming at least one second conductor coupled to the substantially spherical diodes; and depositing or attaching a plurality of substantially spherical lenses suspended in a first polymer. The lenses and the suspending polymer have different indices of refraction. In some embodiments, the lenses and diodes have a ratio of mean diameters or lengths between about 10:1 and 2:1. In various embodiments, the forming, coupling and converting steps are performed by or through a printing process.

Low-cost, high-precision micro-lensed optical fiber providing deep-micrometer to deep-nanometer-level light focusing.

PubMed

Wen, Sy-Bor; Sundaram, Vijay M; McBride, Daniel; Yang, Yu

2016-04-15

A new type of micro-lensed optical fiber through stacking appropriate high-refractive microspheres at designed locations with respect to the cleaved end of an optical fiber is numerically and experimentally demonstrated. This new type of micro-lensed optical fiber can be precisely constructed with low cost and high speed. Deep micrometer-scale and submicrometer-scale far-field light spots can be achieved when the optical fibers are multimode and single mode, respectively. By placing an appropriate teardrop dielectric nanoscale scatterer at the far-field spot of this new type of micro-lensed optical fiber, a deep-nanometer near-field spot can also be generated with high intensity and minimum joule heating, which is valuable in high-speed, high-resolution, and high-power nanoscale detection compared with traditional near-field optical fibers containing a significant portion of metallic material.

Living Additive Manufacturing: Transformation of Parent Gels into Diversely Functionalized Daughter Gels Made Possible by Visible Light Photoredox Catalysis.

PubMed

Chen, Mao; Gu, Yuwei; Singh, Awaneesh; Zhong, Mingjiang; Jordan, Alex M; Biswas, Santidan; Korley, LaShanda T J; Balazs, Anna C; Johnson, Jeremiah A

2017-02-22

Light-initiated additive manufacturing techniques typically rely on layer-by-layer addition or continuous extraction of polymers formed via nonliving, free radical polymerization methods that render the final materials "dead" toward further monomer insertion; the polymer chains within the materials cannot be reactivated to induce chain extension. An alternative "living additive manufacturing" strategy would involve the use of photocontrolled living radical polymerization to spatiotemporally insert monomers into dormant "parent" materials to generate more complex and diversely functionalized "daughter" materials. Here, we demonstrate a proof-of-concept study of living additive manufacturing using end-linked polymer gels embedded with trithiocarbonate iniferters that can be activated by photoinduced single-electron transfer from an organic photoredox catalyst in solution. This system enables the synthesis of a wide range of chemically and mechanically differentiated daughter gels from a single type of parent gel via light-controlled modification of the parent's average composition, strand length, and/or cross-linking density. Daughter gels that are softer than their parent, stiffer than their parent, larger but with the same modulus as their parent, thermally responsive, polarity responsive, healable, and weldable are all realized.

Technological development of multispectral filter assemblies for micro bolometer

NASA Astrophysics Data System (ADS)

Le Goff, Roland; Tanguy, François; Fuss, Philippe; Etcheto, Pierre

2017-11-01

Since 2007 Sodern has successfully developed visible and near infrared multispectral filter assemblies for Earth remote sensing imagers. Filter assembly is manufactured by assembling several sliced filter elements (so-called strips), each corresponding to one spectral band. These strips are cut from wafers using a two dimensional accuracy precision process. In the frame of a 2011 R&T preparatory initiative undertaken by the French agency CNES, the filter assembly concept was adapted by Sodern to the long wave infrared spectral band taken into account the germanium substrate, the multilayer bandpass filters and the F-number of the optics. Indeed the current trend in space instrumentation toward more compact uncooled infrared radiometer leads to replace the filter wheel with a multispectral filter assembly mounted directly above the micro bolometer window. The filter assembly was customized to fit the bolometer size. For this development activity we consider a ULIS VGA LWIR micro bolometer with 640 by 480 pixels and 25 microns pixel pitch. The feasibility of the concept and the ability to withstand space environment were investigated and demonstrated by bread boarding activities. The presentation will contain a detailed description of the bolometer and filter assembly design, the stray light modeling analysis assessing the crosstalk between adjacent spectral bands and the results of the manufacturing and environmental tests (damp heat and thermal vacuum cycling).

Fabrication of spherical mitigation pit on KH2PO4 crystal by micro-milling and modeling of its induced light intensification.

PubMed

Cheng, Jian; Chen, Mingjun; Liao, Wei; Wang, Haijun; Xiao, Yong; Li, Mingquan

2013-07-15

Micro-machining is the most promising method for KH(2)PO(4) crystal to mitigate the surface damage growth in high power laser system. In this work, spherical mitigation pit is fabricated by micro-milling with an efficient machining procedure. The light intensification caused by rear surface features before and after mitigation is numerically modeled based on the finite-difference time-domain method. The results indicate that the occurrence of total internal reflections should be responsible for the largest light intensification inside the crystal. For spherical pits after mitigation, the light intensification can be greatly alleviated by preventing the occurrence of total internal reflections. The light intensification caused by spherical mitigation pit is strongly dependent on the width-depth ratio and it is suggested that the width-depth ratio of spherical mitigation pit must be devised to be larger than 5.0 to achieve the minimal light intensification for the mitigation of surface damage growth. Laser damage tests for KH(2)PO(4) crystal validate that the laser damage resistance of initially damaged surface can be retrieved to near the level of ideal surface by replacing initial damage site with predesigned mitigation pit.

The system analysis of light field information collection based on the light field imaging

NASA Astrophysics Data System (ADS)

Wang, Ye; Li, Wenhua; Hao, Chenyang

2016-10-01

Augmented reality(AR) technology is becoming the study focus, and the AR effect of the light field imaging makes the research of light field camera attractive. The micro array structure was adopted in most light field information acquisition system(LFIAS) since emergence of light field camera, micro lens array(MLA) and micro pinhole array(MPA) system mainly included. It is reviewed in this paper the structure of the LFIAS that the Light field camera commonly used in recent years. LFIAS has been analyzed based on the theory of geometrical optics. Meanwhile, this paper presents a novel LFIAS, plane grating system, we call it "micro aperture array(MAA." And the LFIAS are analyzed based on the knowledge of information optics; This paper proves that there is a little difference in the multiple image produced by the plane grating system. And the plane grating system can collect and record the amplitude and phase information of the field light.

An Experimental Study of a Micro-Projection Enabled Optical Terminal for Short-Range Bidirectional Multi-Wavelength Visible Light Communications

PubMed Central

Tsai, Cheng-Yu; Jiang, Jhih-Shan

2018-01-01

A micro-projection enabled short-range communication (SRC) approach using red-, green- and blue-based light-emitting diodes (RGB-LEDs) has experimentally demonstrated recently that micro-projection and high-speed data transmission can be performed simultaneously. In this research, a reconfigurable design of a polarization modulated image system based on the use of a Liquid Crystal on Silicon based Spatial Light Modulator (LCoS-based SLM) serving as a portable optical terminal capable of micro-projection and bidirectional multi-wavelength communications is proposed and experimentally demonstrated. For the proof of concept, the system performance was evaluated through a bidirectional communication link at a transmission distance over 0.65 m. In order to make the proposed communication system architecture compatible with the data modulation format of future possible wireless communication system, baseband modulation scheme, i.e., Non-Return-to-Zero On-Off-Keying (NRZ_OOK), M-ary Phase Shift Keying (M-PSK) and M-ary Quadrature Amplitude Modulation (M-QAM) were used to investigate the system transmission performance. The experimental results shown that an acceptable BER (satisfying the limitation of Forward Error Correction, FEC standard) and crosstalk can all be achieved in the bidirectional multi-wavelength communication scenario. PMID:29587457

Design and fabrication of AlGaInP-based micro-light-emitting-diode array devices

NASA Astrophysics Data System (ADS)

Bao, Xingzhen; Liang, Jingqiu; Liang, Zhongzhu; Wang, Weibiao; Tian, Chao; Qin, Yuxin; Lü, Jinguang

2016-04-01

An integrated high-resolution (individual pixel size 80 μm×80 μm) solid-state self-emissive active matrix programmed with 320×240 micro-light-emitting-diode arrays structure was designed and fabricated on an AlGaInP semiconductor chip using micro electro-mechanical systems, microstructure and semiconductor fabricating techniques. Row pixels share a p-electrode and line pixels share an n-electrode. We experimentally investigated GaAs substrate thickness affects the electrical and optical characteristics of the pixels. For a 150-μm-thick GaAs substrate, the single pixel output power was 167.4 μW at 5 mA, and increased to 326.4 μW when current increase to 10 mA. The device investigated potentially plays an important role in many fields.

A micro-coupling for micro mechanical systems

NASA Astrophysics Data System (ADS)

Li, Wei; Zhou, Zhixiong; Zhang, Bi; Xiao, Yunya

2016-05-01

The error motions of micro mechanical systems, such as micro-spindles, increase with the increasing of the rotational speed, which not only decreases the rotational accuracy, but also promotes instability and limits the maximum operational speed. One effective way to deal with it is to use micro-flexible couplings between the drive and driven shafts so as to reduce error motions of the driven shaft. But the conventional couplings, such as diaphragm couplings, elastomeric couplings, bellows couplings, and grooved couplings, etc, cannot be directly used because of their large and complicated structures. This study presents a novel micro-coupling that consists of a flexible coupling and a shape memory alloy (SMA)-based clamp for micro mechanical systems. It is monolithic and can be directly machined from a shaft. The study performs design optimization and provides manufacturing considerations, including thermo-mechanical training of the SMA ring for the desired Two-Way-Shape-Memory effect (TWSMe). A prototype micro-coupling and a prototype micro-spindle using the proposed coupling are fabricated and tested. The testing results show that the prototype micro-coupling can bear a torque of above 5 N • mm and an axial force of 8.5 N and be fitted with an SMA ring for clamping action at room temperature (15 °C) and unclamping action below-5 °C. At the same time, the prototype micro-coupling can work at a rotational speed of above 200 kr/min with the application to a high-speed precision micro-spindle. Moreover, the radial runout error of the artifact, as a substitute for the micro-tool, is less than 3 μm while that of turbine shaft is above 7 μm. It can be concluded that the micro-coupling successfully accommodates misalignment errors of the prototype micro-spindle. This research proposes a micro-coupling which is featured with an SMA ring, and it is designed to clamp two shafts, and has smooth transmission, simple assembly, compact structure, zero-maintenance and

Mechanical tolerances study through simulations and experimental characterization for a 1000X micro-concentrator CPV module

NASA Astrophysics Data System (ADS)

Ritou, Arnaud; Voarino, Philippe; Goubault, Baptiste; David, Nadine; Bernardis, Sarah; Raccurt, Olivier; Baudrit, Mathieu

2017-09-01

Existing CPV technology markets are not compliant with a standard configuration. Concentrations vary from several suns to more than 1000 suns and the optical technology used could be very different. Nowadays, the market trends are moving toward more and more compact optical systems in order to exploit the Light Emitting Diode (LED) like approach. The aim is to increase the optical efficiency by using an ultra-short focal distance and to improve thermal management. Moreover the efficiency to weight ratio is increasing and the solar cell size becomes sub-millimetric. With these conditions, more stringent mechanical tolerances are essential to ensure an optimum optical alignment between cells and optics. A new process of micro-concentrator manufacturing is developed in this work. This process enables manufacturing and auto-alignment of Primary Optical Elements (POE) with Secondary Optical Elements (SOE) and solar cells with respect to certain mechanical tolerances. A 1000X micro-concentrator is manufactured with 0.6 x 0.6 mm² triple-junction cells and molded silicone optics. Mechanical alignment defects are studied by ray-tracing simulations and a prototype is characterized with respect to its mechanical behavior. An efficiency of 33.4% is measured with a Cell-to-Module ratio of 77.8%.

High-rate production of micro- and nanostructured surfaces: Injection molding and novel process for metal tooling manufacturing

NASA Astrophysics Data System (ADS)

De Jesus Vega, Marisely

rapidly processed via liquid injection molding. LSR with its excellent mechanical properties, transparency, non-toxicity and rapid molding capabilities can bring the production of micro and nanostructured surfaces from laboratory research facilities to high-rate manufacturing. However, previous research on microstructured surfaces made off LSR does not focus on the processing aspect of this material. Therefore, there is a lack of understanding of how different processing conditions affect the replication of microstructures. Additionally, there are no reports molding nanostructures of LSR. Features between 115 microm and 0.250 microm were molded in this work and the effect of different processing conditions and features sizes were studied. For the last part of this work, a novel metal additive manufacturing technique was used for the production of microstructured surfaces to be used as tooling for injection molding. The printing method consists of metal pastes printed through a tip onto a steel substrate. Prior work has shown spreading and swelling of features when metal pastes extrude out of the printing tip. PDMS was studied as a binder material to minimize spreading and swelling of the features by curing right after printing. In addition, prior work has shown durability of this metal printed tool up to 5000 injection molding cycles. This work compares this durability to durability of commercially available selective laser sintering metal tools. Furthermore, surface roughness was studied as this is one of the most important things to consider when molding microchannels for certain applications.

Micro heat barrier

DOEpatents

Marshall, Albert C.; Kravitz, Stanley H.; Tigges, Chris P.; Vawter, Gregory A.

2003-08-12

A highly effective, micron-scale micro heat barrier structure and process for manufacturing a micro heat barrier based on semiconductor and/or MEMS fabrication techniques. The micro heat barrier has an array of non-metallic, freestanding microsupports with a height less than 100 microns, attached to a substrate. An infrared reflective membrane (e.g., 1 micron gold) can be supported by the array of microsupports to provide radiation shielding. The micro heat barrier can be evacuated to eliminate gas phase heat conduction and convection. Semi-isotropic, reactive ion plasma etching can be used to create a microspike having a cusp-like shape with a sharp, pointed tip (<0.1 micron), to minimize the tip's contact area. A heat source can be placed directly on the microspikes. The micro heat barrier can have an apparent thermal conductivity in the range of 10.sup.-6 to 10.sup.-7 W/m-K. Multiple layers of reflective membranes can be used to increase thermal resistance.

Spatial redistribution of nano-particles using electrokinetic micro-focuser

NASA Astrophysics Data System (ADS)

Garcia, Daniel E.; Silva, Aleidy; Ho, Chih-Ming

2007-09-01

Current microfabrication technologies rely on top-down, photolithographic techniques that are ultimately limited by the wavelength of light. While systems for nanofabrication do exist, they frequently suffer from high costs and slow processing times, creating a need for a new manufacturing paradigm. The combination of top-down and bottom-up fabrication approaches in device construction creates a new paradigm in micro- and nano-manufacturing. The pre-requisite for the realization of the manufacturing paradigm relies on the manipulation of molecules in a deterministic and controlled manner. The use of AC electrokinetic forces, such as dielectrophoresis (DEP) and AC electroosmosis, is a promising technology for manipulating nano-sized particle in a parallel fashion. A three-electrode micro-focusing system was designed to expoit this forces in order to control the spatial distribution of nano-particles in different frequency ranges. Thus far, we have demonstrated the ability to concentrate 40 nm and 300 nm diameter particles using a 50 μm diameter focusing system. AC electroosmotic motion of the nano-particles was observed while using low frequencies (in a range of 30 Hz - 1 KHz). By using different frequencies and changing the ground location, we have manipulated the nano-particles into circular band structures with different width, and focused the nanoparticles into circular spots with different diameters. Currently, we are in the progress of optimizing the operation parameters (e.g. frequency and AC voltages) by using the technique of particle image velocimetry (PIV). In the future, design of different electrode geometries and the numerical simulation of electric field distribution will be carried out to manipulate the nano-particles into a variety of geometries.

Micro-laser

DOEpatents

Hutchinson, Donald P.; Richards, Roger K.

2003-07-22

A micro-laser is disclosed which includes a waveguide, a first and a second subwavelength resonant grating in the waveguide, and at least one photonic band gap resonant structure (PBG) in the waveguide and at least one amplifying medium in the waveguide. PBG features are positioned between the first and second subwavelength resonant gratings and allow introduction of amplifying mediums into the highly resonant guided micro-laser microcavity. The micro-laser may be positioned on a die of a bulk substrate material with one or more electronic and optical devices and may be communicably connected to the same. A method for fabricating a micro-laser is disclosed. A method for tuning the micro-laser is also disclosed. The micro-laser may be used as an optical regenerator, or a light source for data transfer or for optical computing.

Fabrication of a Flexible Micro CO Sensor for Micro Reformer Applications

PubMed Central

Lee, Chi-Yuan; Chang, Chi-Chung; Lo, Yi-Man

2010-01-01

Integration of a reformer and a proton exchange membrane fuel cell (PEMFC) is problematic due to the presence in the gas from the reforming process of a slight amount of carbon monoxide. Carbon monoxide poisons the catalyst of the proton exchange membrane fuel cell subsequently degrading the fuel cell performance, and necessitating the sublimation of the reaction gas before supplying to fuel cells. Based on the use of micro-electro-mechanical systems (MEMS) technology to manufacture flexible micro CO sensors, this study elucidates the relation between a micro CO sensor and different SnO2 thin film thicknesses. Experimental results indicate that the sensitivity increases at temperatures ranging from 100–300 °C. Additionally, the best sensitivity is obtained at a specific temperature. For instance, the best sensitivity of SnO2 thin film thickness of 100 nm at 300 °C is 59.3%. Moreover, a flexible micro CO sensor is embedded into a micro reformer to determine the CO concentration in each part of a micro reformer in the future, demonstrating the inner reaction of a micro reformer in depth and immediate detection. PMID:22163494

Eye vision system using programmable micro-optics and micro-electronics

NASA Astrophysics Data System (ADS)

Riza, Nabeel A.; Amin, M. Junaid; Riza, Mehdi N.

2014-02-01

Proposed is a novel eye vision system that combines the use of advanced micro-optic and microelectronic technologies that includes programmable micro-optic devices, pico-projectors, Radio Frequency (RF) and optical wireless communication and control links, energy harvesting and storage devices and remote wireless energy transfer capabilities. This portable light weight system can measure eye refractive powers, optimize light conditions for the eye under test, conduct color-blindness tests, and implement eye strain relief and eye muscle exercises via time sequenced imaging. Described is the basic design of the proposed system and its first stage system experimental results for vision spherical lens refractive error correction.

Growth of micro-crystals in solution by in-situ heating via continuous wave infrared laser light and an absorber

NASA Astrophysics Data System (ADS)

Pathak, Shashank; Dharmadhikari, Jayashree A.; Thamizhavel, A.; Mathur, Deepak; Dharmadhikari, Aditya K.

2016-01-01

We report on growth of micro-crystals such as sodium chloride (NaCl), copper sulphate (CuSO4), potassium di-hydrogen phosphate (KDP) and glycine (NH2CH2COOH) in solution by in-situ heating using continuous wave Nd:YVO4 laser light. Crystals are grown by adding single walled carbon nanotubes (SWNT). The SWNTs absorb 1064 nm light and act as an in-situ heat source that vaporizes the solvent producing microcrystals. The temporal dynamics of micro-crystal growth is investigated by varying experimental parameters such as SWNT bundle size and incident laser power. We also report crystal growth without SWNT in an absorbing medium: copper sulphate in water. Even though the growth dynamics with SWNT and copper sulphate are significantly different, our results indicate that bubble formation is necessary for nucleation. Our simple method may open up new vistas for rapid growth of seed crystals especially for examining the crystallizability of inorganic and organic materials.

A review of micro-powder injection moulding as a microfabrication technique

NASA Astrophysics Data System (ADS)

Attia, Usama M.; Alcock, Jeffrey R.

2011-04-01

Micro-powder injection moulding (µPIM) is a fast-developing micro-manufacturing technique for the production of metal and ceramic components. Shape complexity, dimensional accuracy, replication fidelity, material variety combined with high-volume capabilities are some of the key advantages of the technology. This review assesses the capabilities and limitations of µPIM as a micro-manufacturing technique by reviewing the latest developments in the area and by considering potential improvements. The basic elements of the process chain, variant processes and simulation attempts are discussed and evaluated. Challenges and research gaps are highlighted, and potential areas for improvement are presented.

Solid State Lighting OLED Manufacturing Roundtable Summary

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

none,

2010-03-31

Summary of a meeting of OLED experts to develop proposed priority tasks for the Manufacturing R&D initiative, including task descriptions, discussion points, recommendations, and presentation highlights.

Benchmarks of Global Clean Energy Manufacturing

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

Sandor, Debra; Chung, Donald; Keyser, David

The Clean Energy Manufacturing Analysis Center (CEMAC), sponsored by the U.S. Department of Energy (DOE) Office of Energy Efficiency and Renewable Energy (EERE), provides objective analysis and up-to-date data on global supply chains and manufacturing of clean energy technologies. Benchmarks of Global Clean Energy Manufacturing sheds light on several fundamental questions about the global clean technology manufacturing enterprise: How does clean energy technology manufacturing impact national economies? What are the economic opportunities across the manufacturing supply chain? What are the global dynamics of clean energy technology manufacturing?

49 CFR 579.27 - Reporting requirements for manufacturers of fewer than 100 buses annually, for manufacturers of...

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 7 2013-10-01 2013-10-01 false Reporting requirements for manufacturers of fewer than 100 buses annually, for manufacturers of fewer than 500 emergency vehicles annually, for manufacturers of fewer than 5,000 light vehicles, medium-heavy vehicles (other than buses and emergency vehicles), motorcycles or trailers annually, for...

49 CFR 579.27 - Reporting requirements for manufacturers of fewer than 100 buses annually, for manufacturers of...

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 7 2011-10-01 2011-10-01 false Reporting requirements for manufacturers of fewer than 100 buses annually, for manufacturers of fewer than 500 emergency vehicles annually, for manufacturers of fewer than 5,000 light vehicles, medium-heavy vehicles (other than buses and emergency vehicles), motorcycles or trailers annually, for...

49 CFR 579.27 - Reporting requirements for manufacturers of fewer than 100 buses annually, for manufacturers of...

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 7 2014-10-01 2014-10-01 false Reporting requirements for manufacturers of fewer than 100 buses annually, for manufacturers of fewer than 500 emergency vehicles annually, for manufacturers of fewer than 5,000 light vehicles, medium-heavy vehicles (other than buses and emergency vehicles), motorcycles or trailers annually, for...

49 CFR 579.27 - Reporting requirements for manufacturers of fewer than 100 buses annually, for manufacturers of...

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 7 2012-10-01 2012-10-01 false Reporting requirements for manufacturers of fewer than 100 buses annually, for manufacturers of fewer than 500 emergency vehicles annually, for manufacturers of fewer than 5,000 light vehicles, medium-heavy vehicles (other than buses and emergency vehicles), motorcycles or trailers annually, for...

Detection of viability of micro-algae cells by optofluidic hologram pattern.

PubMed

Wang, Junsheng; Yu, Xiaomei; Wang, Yanjuan; Pan, Xinxiang; Li, Dongqing

2018-03-01

A rapid detection of micro-algae activity is critical for analysis of ship ballast water. A new method for detecting micro-algae activity based on lens-free optofluidic holographic imaging is presented in this paper. A compact lens-free optofluidic holographic imaging device was developed. This device is mainly composed of a light source, a small through-hole, a light propagation module, a microfluidic chip, and an image acquisition and processing module. The excited light from the light source passes through a small hole to reach the surface of the micro-algae cells in the microfluidic chip, and a holographic image is formed by the diffraction light of surface of micro-algae cells. The relation between the characteristics in the hologram pattern and the activity of micro-algae cells was investigated by using this device. The characteristics of the hologram pattern were extracted to represent the activity of micro-algae cells. To demonstrate the accuracy of the presented method and device, four species of micro-algae cells were employed as the test samples and the comparison experiments between the alive and dead cells of four species of micro-algae were conducted. The results show that the developed method and device can determine live/dead microalgae cells accurately.

Micro optical fiber display switch based on the magnetohydrodynamic (MHD) principle

NASA Astrophysics Data System (ADS)

Lian, Kun; Heng, Khee-Hang

2001-09-01

This paper reports on a research effort to design, microfabricate and test an optical fiber display switch based on magneto hydrodynamic (MHD) principal. The switch is driven by the Lorentz force and can be used to turn on/off the light. The SU-8 photoresist and UV light source were used for prototype fabrication in order to lower the cost. With a magnetic field supplied by an external permanent magnet, and a plus electrical current supplied across the two inert sidewall electrodes, the distributed body force generated will produce a pressure difference on the fluid mercury in the switch chamber. By change the direction of current flow, the mercury can turn on or cut off the light pass in less than 10 ms. The major advantages of a MHD-based micro-switch are that it does not contain any solid moving parts and power consumption is much smaller comparing to the relay type switches. This switch can be manufactured by molding gin batch production and may have potential applications in extremely bright traffic control,, high intensity advertising display, and communication.

Self-assembly micro optical filter

NASA Astrophysics Data System (ADS)

Zhang, Ping (Cerina); Le, Kevin; Malalur-Nagaraja-Rao, Smitha; Hsu, Lun-Chen; Chiao, J.-C.

2006-01-01

Optical communication and sensor industry face critical challenges in manufacturing for system integration. Due to the assembly complexity and integration platform variety, micro optical components require costly alignment and assembly procedures, in which many required manual efforts. Consequently, self-assembly device architectures have become a great interest and could provide major advantages over the conventional optical devices. In this paper, we discussed a self-assembly integration platform for micro optical components. To demonstrate the adaptability and flexibility of the proposed optical device architectures, we chose a commercially available MEMS fabrication foundry service - MUMPs (Multi-User MEMS Process). In this work, polysilicon layers of MUMPS are used as the 3-D structural material for construction of micro component framework and actuators. However, because the polysilicon has high absorption in the visible and near infrared wavelength ranges, it is not suitable for optical interaction. To demonstrate the required optical performance, hybrid integration of materials was proposed and implemented. Organic compound materials were applied on the silicon-based framework to form the required optical interfaces. Organic compounds provide good optical transparency, flexibility to form filters or lens and inexpensive manufacturing procedures. In this paper, we have demonstrated a micro optical filter integrated with self-assembly structures. We will discuss the self-assembly mechanism, optical filter designs, fabrication issues and results.

Inactivation of foodborne pathogenic and spoilage micro-organisms using ultraviolet-A light in combination with ferulic acid.

PubMed

Shirai, A; Watanabe, T; Matsuki, H

2017-02-01

The low energy of UV-A (315-400 nm) is insufficient for disinfection. To improve UV-A disinfection technology, we evaluated the effect of ferulic acid (FA) addition on disinfection by UV-A light-emitting diode (LED) (350-385 nm) against various food spoilers and pathogens (seven bacteria and four fungi species). Photoantimicrobial assays were performed at FA concentrations below the MIC. The MIC of the isomerized FA, consisting of 93% cis-form and 7% trans-form, was very similar to that of the commercially available FA (trans-form). Irradiation with UV-A (1·0 J cm -2 ) in the presence of 100 mg l -1 FA resulted in enhanced reducing of all of the tested bacterial strains. A combination of UV-A (10 J cm -2 ) and 1000 mg l -1 FA resulted in enhanced reducing of Saccharomyces cerevisiae and one of the tested filamentous fungi. These results demonstrated that the combination of a short-term application of UV-A and FA at a low concentration yielded synergistic enhancement of antimicrobial activity, especially against bacteria. Microbial contamination is one of the most serious problems for foods, fruit and sugar thick juices. UV light is suitable for the nonthermal decontamination of food products by inactivating the contaminating micro-organisms. However, UV-A exposure is insufficient for disinfection. This study demonstrates that the combination of UV-A LED light (350-385 nm), which is not hazardous to human eyes and skin, and ferulic acid (FA), a known phytochemical and food additive, provides synergistic antimicrobial activity against foodborne pathogenic and spoilage micro-organisms. Therefore, FA addition to UV-A light treatment may be useful for improvement of UV-A disinfection technology to prevent food deterioration. © 2016 The Society for Applied Microbiology.

Efficacy of UV-Pit-light traps for discerning micro-habitat-specific beetle and ant species related with different oil palm age stands and tropical annual seasons for accurate ecology and diversity interpretations

NASA Astrophysics Data System (ADS)

Ahmad Bukhary, A. K.; Ruslan, M. Y.; Mohd. Fauzi, M. M.; Nicholas, S.; Muhamad Fahmi, M. H.; Izfa Riza, H.; Idris, A. B.

2015-09-01

A newly innovated and efficient UV-Pit-light Trap is described and the results of the experiments on its efficacy that were carried out within different oil palm age stands of the year 2013 were evaluated and compared with previous study year of 2010, with out the implementation of the UV-Pit-light Trap. In 2013 the UV-Pit-light Traps, the Malaise Traps, and the Pit-fall Traps were employed, while in 2010, the conventional canopy-height UV-Light Traps, Malaise Traps, and the Pit-fall Traps were employed. The UV-Pit-light traps caught more beetle and ant families, morpho-species, and individuals per species compared with the passive Pit-fall traps. The UV-Pit-light Trap targets different subsets of the oil palm beetles and ants' communities, specifying on epigaeic-related micro-habitats, with different oil palm age stands have different compositions of micro-habitats. The UV-Pit-light Traps have the dual quality for satisfying both the biological and statistical data requirements and evaluations. There were no significant difference between the UV-Pit-light Traps and the passive Pit-fall Traps, while the trapping difference with the Malaise traps for different seasons of the year 2013. The UV-Pit-light Traps and the Malaise Traps were complementary to each other, detecting the activities of beetles and ants around the epigaeic-related micro-habitats or having active flight activities respectively according to annual seasons. The UV-Pit-light Trap is an oil-palm specific type of passive trapping system, focusing on the insect species dwelling the upper-ground/epigaeic micro-habitats.

Analysis of creating an innovative micro-lens made of polydimethylsiloxane polymer on the end of the optical fibers

NASA Astrophysics Data System (ADS)

Zboril, O.; Cubik, J.; Nedoma, J.; Fajkus, M.; Novak, M.; Jargus, J.; Stratil, T.; Vasinek, V.

2017-10-01

The article describes a method for fabrication of polymer optical micro-lenses using polydimethylsiloxane (PDMS) at the end of optical fibers. PDMS is an optically clear substance having a refractive index very similar to the optical fibers. Therefore it is an interesting material for optical purposes. PDMS is characterized by resistance to electromagnetic interference (EMI), enabling the use in electromagnetically noisy environments. These lenses could be used for example for the security applications. For the manufacture of the micro-lenses is used Sylgard silicone elastomer 184. When applied to the end of conventional optical fiber is cured by treatment at 100 °C +/- 5 °C. Authors performed a series of experimental measurements. The optical characteristics of the treated fibers compared with conventional fibers without micro-lenses. The fibers provided with optical lenses made of PDMS may be used for security applications, in the visible light communication (VLC) or as a microprobe.

Reconfigurable and responsive droplet-based compound micro-lenses

PubMed Central

Nagelberg, Sara; Zarzar, Lauren D.; Nicolas, Natalie; Subramanian, Kaushikaram; Kalow, Julia A.; Sresht, Vishnu; Blankschtein, Daniel; Barbastathis, George; Kreysing, Moritz; Swager, Timothy M.; Kolle, Mathias

2017-01-01

Micro-scale optical components play a crucial role in imaging and display technology, biosensing, beam shaping, optical switching, wavefront-analysis, and device miniaturization. Herein, we demonstrate liquid compound micro-lenses with dynamically tunable focal lengths. We employ bi-phase emulsion droplets fabricated from immiscible hydrocarbon and fluorocarbon liquids to form responsive micro-lenses that can be reconfigured to focus or scatter light, form real or virtual images, and display variable focal lengths. Experimental demonstrations of dynamic refractive control are complemented by theoretical analysis and wave-optical modelling. Additionally, we provide evidence of the micro-lenses' functionality for two potential applications—integral micro-scale imaging devices and light field display technology—thereby demonstrating both the fundamental characteristics and the promising opportunities for fluid-based dynamic refractive micro-scale compound lenses. PMID:28266505

Reconfigurable and responsive droplet-based compound micro-lenses.

PubMed

Nagelberg, Sara; Zarzar, Lauren D; Nicolas, Natalie; Subramanian, Kaushikaram; Kalow, Julia A; Sresht, Vishnu; Blankschtein, Daniel; Barbastathis, George; Kreysing, Moritz; Swager, Timothy M; Kolle, Mathias

2017-03-07

Micro-scale optical components play a crucial role in imaging and display technology, biosensing, beam shaping, optical switching, wavefront-analysis, and device miniaturization. Herein, we demonstrate liquid compound micro-lenses with dynamically tunable focal lengths. We employ bi-phase emulsion droplets fabricated from immiscible hydrocarbon and fluorocarbon liquids to form responsive micro-lenses that can be reconfigured to focus or scatter light, form real or virtual images, and display variable focal lengths. Experimental demonstrations of dynamic refractive control are complemented by theoretical analysis and wave-optical modelling. Additionally, we provide evidence of the micro-lenses' functionality for two potential applications-integral micro-scale imaging devices and light field display technology-thereby demonstrating both the fundamental characteristics and the promising opportunities for fluid-based dynamic refractive micro-scale compound lenses.

Additive manufacturing of reflective optics: evaluating finishing methods

NASA Astrophysics Data System (ADS)

Leuteritz, G.; Lachmayer, R.

2018-02-01

Individually shaped light distributions become more and more important in lighting technologies and thus the importance of additively manufactured reflectors increases significantly. The vast field of applications ranges from automotive lighting to medical imaging and bolsters the statement. However, the surfaces of additively manufactured reflectors suffer from insufficient optical properties even when manufactured using optimized process parameters for the Selective Laser Melting (SLM) process. Therefore post-process treatments of reflectors are necessary in order to further enhance their optical quality. This work concentrates on the effectiveness of post-process procedures for reflective optics. Based on already optimized aluminum reflectors, which are manufactured with a SLM machine, the parts are differently machined after the SLM process. Selected finishing methods like laser polishing, sputtering or sand blasting are applied and their effects quantified and compared. The post-process procedures are investigated on their impact on surface roughness and reflectance as well as geometrical precision. For each finishing method a demonstrator will be created and compared to a fully milled sample and among themselves. Ultimately, guidelines are developed in order to figure out the optimal treatment of additively manufactured reflectors regarding their optical and geometrical properties. Simulations of the light distributions will be validated with the developed demonstrators.

Anisotropy of Photopolymer Parts Made by Digital Light Processing

PubMed Central

Monzón, Mario; Ortega, Zaida; Hernández, Alba; Paz, Rubén; Ortega, Fernando

2017-01-01

Digital light processing (DLP) is an accurate additive manufacturing (AM) technology suitable for producing micro-parts by photopolymerization. As most AM technologies, anisotropy of parts made by DLP is a key issue to deal with, taking into account that several operational factors modify this characteristic. Design for this technology and photopolymers becomes a challenge because the manufacturing process and post-processing strongly influence the mechanical properties of the part. This paper shows experimental work to demonstrate the particular behavior of parts made using DLP. Being different to any other AM technology, rules for design need to be adapted. Influence of build direction and post-curing process on final mechanical properties and anisotropy are reported and justified based on experimental data and theoretical simulation of bi-material parts formed by fully-cured resin and partially-cured resin. Three photopolymers were tested under different working conditions, concluding that post-curing can, in some cases, correct the anisotropy, mainly depending on the nature of photopolymer. PMID:28772426

Monte Carlo analysis for the determination of the conic constant of an aspheric micro lens based on a scanning white light interferometric measurement

NASA Astrophysics Data System (ADS)

Gugsa, Solomon A.; Davies, Angela

2005-08-01

Characterizing an aspheric micro lens is critical for understanding the performance and providing feedback to the manufacturing. We describe a method to find the best-fit conic of an aspheric micro lens using a least squares minimization and Monte Carlo analysis. Our analysis is based on scanning white light interferometry measurements, and we compare the standard rapid technique where a single measurement is taken of the apex of the lens to the more time-consuming stitching technique where more surface area is measured. Both are corrected for tip/tilt based on a planar fit to the substrate. Four major parameters and their uncertainties are estimated from the measurement and a chi-square minimization is carried out to determine the best-fit conic constant. The four parameters are the base radius of curvature, the aperture of the lens, the lens center, and the sag of the lens. A probability distribution is chosen for each of the four parameters based on the measurement uncertainties and a Monte Carlo process is used to iterate the minimization process. Eleven measurements were taken and data is also chosen randomly from the group during the Monte Carlo simulation to capture the measurement repeatability. A distribution of best-fit conic constants results, where the mean is a good estimate of the best-fit conic and the distribution width represents the combined measurement uncertainty. We also compare the Monte Carlo process for the stitched data and the not stitched data. Our analysis allows us to analyze the residual surface error in terms of Zernike polynomials and determine uncertainty estimates for each coefficient.

Manipulation of Nano-/Micro Particles Using Light-Actuated Marangoni Tweezers

NASA Astrophysics Data System (ADS)

Lu, Cunjing; Varanakkottu, Subramanyan; Hardt, Steffen; Nano-; Microfluidics, Center of Smart Interfaces, TU Darmstadt Team

2015-11-01

The ability to manipulate and produce patterns of nano-/micro objects has been of great interest from both a fundamental and an application point of view. Here we demonstrate particle patterning using an optical landscape and optical nanoparticle manipulation based on light-actuated Marangoni tweezers. A liquid film with a photosurfactant which exists in two isomeric states (cis and trans) is employed for that purpose. Under multiple laser spots created by diffractive optical elements from a He-Cd laser, cis-rich regions with higher surface tension than unexposed trans-rich regions are created, resulting in converging Marangoni flows directing particles attached to the liquid surface toward the irradiated area. 10 μm polystyrene particles and 600 nm λ-DNA molecules distributed over the liquid surface move to the nearest laser spot and can be arranged in specific patterns. Furthermore, 100 nm polystyrene particles and 20 nm quantum dots can also be trapped, and the 100 nm particles can be driven along quite complex trajectories. Compared to conventional optical tweezers, the corresponding power requirements are much lower.

Manufacturing process of nanofluidics using afm probe

NASA Astrophysics Data System (ADS)

Karingula, Varun Kumar

A new process for fabricating a nano fluidic device that can be used in medical application is developed and demonstrated. Nano channels are fabricated using a nano tip in indentation mode on AFM (Atomic Force Microscopy). The nano channels are integrated between the micro channels and act as a filter to separate biomolecules. Nano channels of 4 to7 m in length, 80nm in width, and at varying depths from 100nm to 850 nm allow the resulting device to separate selected groups of lysosomes and other viruses. Sharply developed vertical micro channels are produced from a deep reaction ion etching followed by deposition of different materials, such as gold and polymers, on the top surface, allowing the study of alternative ways of manufacturing a nanofluidic device. PDMS (Polydimethylsiloxane) bonding is performed to close the top surface of the device. An experimental setup is used to test and validate the device by pouring fluid through the channels. A detailed cost evaluation is conducted to compare the economical merits of the proposed process. It is shown that there is a 47:7% manufacturing time savings and a 60:6% manufacturing cost savings.

Continuous Digital Light Processing (cDLP): Highly Accurate Additive Manufacturing of Tissue Engineered Bone Scaffolds.

PubMed

Dean, David; Jonathan, Wallace; Siblani, Ali; Wang, Martha O; Kim, Kyobum; Mikos, Antonios G; Fisher, John P

2012-03-01

Highly accurate rendering of the external and internal geometry of bone tissue engineering scaffolds effects fit at the defect site, loading of internal pore spaces with cells, bioreactor-delivered nutrient and growth factor circulation, and scaffold resorption. It may be necessary to render resorbable polymer scaffolds with 50 μm or less accuracy to achieve these goals. This level of accuracy is available using Continuous Digital Light processing (cDLP) which utilizes a DLP(®) (Texas Instruments, Dallas, TX) chip. One such additive manufacturing device is the envisionTEC (Ferndale, MI) Perfactory(®). To use cDLP we integrate a photo-crosslinkable polymer, a photo-initiator, and a biocompatible dye. The dye attenuates light, thereby limiting the depth of polymerization. In this study we fabricated scaffolds using the well-studied resorbable polymer, poly(propylene fumarate) (PPF), titanium dioxide (TiO(2)) as a dye, Irgacure(®) 819 (BASF [Ciba], Florham Park, NJ) as an initiator, and diethyl fumarate as a solvent to control viscosity.

Enhancement of the light output power of InGaN/GaN light-emitting diodes grown on pyramidal patterned sapphire substrates in the micro- and nanoscale

NASA Astrophysics Data System (ADS)

Gao, Haiyong; Yan, Fawang; Zhang, Yang; Li, Jinmin; Zeng, Yiping; Wang, Guohong

2008-01-01

Sapphire substrates were patterned by a chemical wet etching technique in the micro- and nanoscale to enhance the light output power of InGaN/GaN light-emitting diodes (LEDs). InGaN/GaN LEDs on a pyramidal patterned sapphire substrate in the microscale (MPSS) and pyramidal patterned sapphire substrate in the nanoscale (NPSS) were grown by metalorganic chemical vapor deposition. The characteristics of the LEDs fabricated on the MPSS and NPSS prepared by wet etching were studied and the light output powers of the LEDs fabricated on the MPSS and NPSS increased compared with that of the conventional LEDs fabricated on planar sapphire substrates. In comparison with the planar sapphire substrate, an enhancement in output power of about 29% and 48% is achieved with the MPSS and NPSS at an injection current of 20 mA, respectively. This significant enhancement is attributable to the improvement of the epitaxial quality of GaN-based epilayers and the improvement of the light extraction efficiency by patterned sapphire substrates. Additionally, the NPSS is more effective to enhance the light output power than the MPSS.

Temperature characteristics of epitaxially grown InAs quantum dot micro-disk lasers on silicon for on-chip light sources

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

Wan, Yating; Li, Qiang; Lau, Kei May, E-mail: eekmlau@ust.hk

2016-07-04

Temperature characteristics of optically pumped micro-disk lasers (MDLs) incorporating InAs quantum dot active regions are investigated for on-chip light sources. The InAs quantum dot MDLs were grown on V-groove patterned (001) silicon, fully compatible with the prevailing complementary metal oxide-semiconductor technology. By combining the high-quality whispering gallery modes and 3D confinement of injected carriers in quantum dot micro-disk structures, we achieved lasing operation from 10 K up to room temperature under continuous optical pumping. Temperature dependences of the threshold, lasing wavelength, slope efficiency, and mode linewidth are examined. An excellent characteristic temperature T{sub o} of 105 K has been extracted.

Development of a micro-mechanical valve in a novel glaucoma implant.

PubMed

Siewert, Stefan; Schultze, Christine; Schmidt, Wolfram; Hinze, Ulf; Chichkov, Boris; Wree, Andreas; Sternberg, Katrin; Allemann, Reto; Guthoff, Rudolf; Schmitz, Klaus-Peter

2012-10-01

This paper describes methods for design, manufacturing and characterization of a micro-mechanical valve for a novel glaucoma implant. The implant is designed to drain aqueous humour from the anterior chamber of the eye into the suprachoroidal space in case of an elevated intraocular pressure (IOP). In contrast to any existing glaucoma drainage device (GDD), the valve mechanism is located in the anterior chamber and there, surrounded by aqueous humour, immune to fibrosis induced failure. For the prevention of hypotony the micro-mechanical valve is designed to open if the physiological pressure difference between the anterior chamber and the suprachoroidal space in the range of 0.8 mmHg to 3.7 mmHg is exceeded. In particular the work includes: (i) manufacturing and morphological characterization of polymer tubing, (ii) mechanical material testing as basis for (iii) the design of micro-mechanical valves using finite element analysis (FEA), (iv) manufacturing of microstent prototypes including micro-mechanical valves by femtosecond laser micromachining and (v) the experimental fluid-mechanical characterization of the manufactured microstent prototypes with regard to valve opening pressure. The considered materials polyurethane (PUR) and silicone (SIL) exhibit low elastic modulus and high extensibility. The unique valve design enables a low opening pressure of micro-mechanical valves. An ideal valve design for PUR and SIL with an experimentally determined opening pressure of 2 mmHg and 3.7 mmHg is identified. The presented valve approach is suitable for the inhibition of hypotony as a major limitation of today's GDD and will potentially improve the minimally invasive treatment of glaucoma.

Coordinated regulation of Arabidopsis microRNA biogenesis and red light signaling through Dicer-like 1 and phytochrome-interacting factor 4

PubMed Central

Sun, Zhenfei; Li, Min; Zhou, Ying; Guo, Tongtong; Liu, Yin; Zhang, Hui

2018-01-01

Light and microRNAs (miRNAs) are key external and internal signals for plant development, respectively. However, the relationship between the light signaling and miRNA biogenesis pathways remains unknown. Here we found that miRNA processer proteins DCL1 and HYL1 interact with a basic helix-loop-helix (bHLH) transcription factor, phytochrome-interacting factor 4 (PIF4), which mediates the destabilization of DCL1 during dark-to-red-light transition. PIF4 acts as a transcription factor for some miRNA genes and is necessary for the proper accumulation of miRNAs. DCL1, HYL1, and mature miRNAs play roles in the regulation of plant hypocotyl growth. These results uncovered a previously unknown crosstalk between miRNA biogenesis and red light signaling through the PIF4-dependent regulation of miRNA transcription and processing to affect red-light-directed plant photomorphogenesis. PMID:29522510

Living additive manufacturing: Transformation of parent gels into diversely functionalized daughter gels made possible by visible light photoredox catalysis

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

Chen, Mao; Gu, Yuwei; Singh, Awaneesh

Light-initiated additive manufacturing techniques typically rely on layer-by-layer addition or continuous extraction of polymers formed via nonliving, free radical polymerization methods that render the final materials “dead” toward further monomer insertion; the polymer chains within the materials cannot be reactivated to induce chain extension. An alternative “living additive manufacturing” strategy would involve the use of photocontrolled living radical polymerization to spatiotemporally insert monomers into dormant “parent” materials to generate more complex and diversely functionalized “daughter” materials. Here, we demonstrate a proof-of-concept study of living additive manufacturing using end-linked polymer gels embedded with trithiocarbonate iniferters that can be activated by photoinducedmore » single-electron transfer from an organic photoredox catalyst in solution. This system enables the synthesis of a wide range of chemically and mechanically differentiated daughter gels from a single type of parent gel via light-controlled modification of the parent’s average composition, strand length, and/or cross-linking density. Furthermore, daughter gels that are softer than their parent, stiffer than their parent, larger but with the same modulus as their parent, thermally responsive, polarity responsive, healable, and weldable are all realized.« less

Living Additive Manufacturing: Transformation of Parent Gels into Diversely Functionalized Daughter Gels Made Possible by Visible Light Photoredox Catalysis

PubMed Central

2017-01-01

Light-initiated additive manufacturing techniques typically rely on layer-by-layer addition or continuous extraction of polymers formed via nonliving, free radical polymerization methods that render the final materials “dead” toward further monomer insertion; the polymer chains within the materials cannot be reactivated to induce chain extension. An alternative “living additive manufacturing” strategy would involve the use of photocontrolled living radical polymerization to spatiotemporally insert monomers into dormant “parent” materials to generate more complex and diversely functionalized “daughter” materials. Here, we demonstrate a proof-of-concept study of living additive manufacturing using end-linked polymer gels embedded with trithiocarbonate iniferters that can be activated by photoinduced single-electron transfer from an organic photoredox catalyst in solution. This system enables the synthesis of a wide range of chemically and mechanically differentiated daughter gels from a single type of parent gel via light-controlled modification of the parent’s average composition, strand length, and/or cross-linking density. Daughter gels that are softer than their parent, stiffer than their parent, larger but with the same modulus as their parent, thermally responsive, polarity responsive, healable, and weldable are all realized. PMID:28280779

Living additive manufacturing: Transformation of parent gels into diversely functionalized daughter gels made possible by visible light photoredox catalysis

DOE PAGES

Chen, Mao; Gu, Yuwei; Singh, Awaneesh; ...

2017-01-13

Light-initiated additive manufacturing techniques typically rely on layer-by-layer addition or continuous extraction of polymers formed via nonliving, free radical polymerization methods that render the final materials “dead” toward further monomer insertion; the polymer chains within the materials cannot be reactivated to induce chain extension. An alternative “living additive manufacturing” strategy would involve the use of photocontrolled living radical polymerization to spatiotemporally insert monomers into dormant “parent” materials to generate more complex and diversely functionalized “daughter” materials. Here, we demonstrate a proof-of-concept study of living additive manufacturing using end-linked polymer gels embedded with trithiocarbonate iniferters that can be activated by photoinducedmore » single-electron transfer from an organic photoredox catalyst in solution. This system enables the synthesis of a wide range of chemically and mechanically differentiated daughter gels from a single type of parent gel via light-controlled modification of the parent’s average composition, strand length, and/or cross-linking density. Furthermore, daughter gels that are softer than their parent, stiffer than their parent, larger but with the same modulus as their parent, thermally responsive, polarity responsive, healable, and weldable are all realized.« less

Pattern-Directed Ordering of Spin-Dewetted Liquid Crystal Micro- or Nanodroplets as Pixelated Light Reflectors and Locomotives.

PubMed

Ravi, Bolleddu; Chakraborty, Snigdha; Bhattacharjee, Mitradip; Mitra, Shirsendu; Ghosh, Abir; Gooh Pattader, Partho Sarathi; Bandyopadhyay, Dipankar

2017-01-11

Chemical pattern directed spin-dewetting of a macroscopic droplet composed of a dilute organic solution of liquid crystal (LC) formed an ordered array of micro- and nanoscale LC droplets. Controlled evaporation of the spin-dewetted droplets through vacuum drying could further miniaturize the size to the level of ∼90 nm. The size, periodicity, and spacing of these mesoscale droplets could be tuned with the variations in the initial loading of LC in the organic solution, the strength of the centripetal force on the droplet, and the duration of the evaporation. A simple theoretical model was developed to predict the spacing between the spin-dewetted droplets. The patterned LC droplets showed a reversible phase transition from nematic to isotropic and vice versa with the periodic exposure of a solvent vapor and its removal. A similar phase transition behavior was also observed with the periodic increase or reduction of temperature, suggesting their usefulness as vapor or temperature sensors. Interestingly, when the spin-dewetted droplets were confined between a pair of electrodes and an external electric field was applied, the droplets situated at the hydrophobic patches showed light-reflecting properties under the polarization microscopy highlighting their importance in the development of micro- or nanoscale LC displays. The digitized LC droplets, which were stationary otherwise, showed dielectrophoretic locomotion under the guidance of the external electric field beyond a threshold intensity of the field. Remarkably, the motion of these droplets could be restricted to the hydrophilic zones, which were confined between the hydrophobic patches of the chemically patterned surface. The findings could significantly contribute in the development of futuristic vapor or temperature sensors, light reflectors, and self-propellers using the micro- or nanoscale digitized LC droplets.

Advanced Material Strategies for Next-Generation Additive Manufacturing

PubMed Central

Chang, Jinke; He, Jiankang; Zhou, Wenxing; Lei, Qi; Li, Xiao; Li, Dichen

2018-01-01

Additive manufacturing (AM) has drawn tremendous attention in various fields. In recent years, great efforts have been made to develop novel additive manufacturing processes such as micro-/nano-scale 3D printing, bioprinting, and 4D printing for the fabrication of complex 3D structures with high resolution, living components, and multimaterials. The development of advanced functional materials is important for the implementation of these novel additive manufacturing processes. Here, a state-of-the-art review on advanced material strategies for novel additive manufacturing processes is provided, mainly including conductive materials, biomaterials, and smart materials. The advantages, limitations, and future perspectives of these materials for additive manufacturing are discussed. It is believed that the innovations of material strategies in parallel with the evolution of additive manufacturing processes will provide numerous possibilities for the fabrication of complex smart constructs with multiple functions, which will significantly widen the application fields of next-generation additive manufacturing. PMID:29361754

Advanced Material Strategies for Next-Generation Additive Manufacturing.

PubMed

Chang, Jinke; He, Jiankang; Mao, Mao; Zhou, Wenxing; Lei, Qi; Li, Xiao; Li, Dichen; Chua, Chee-Kai; Zhao, Xin

2018-01-22

Additive manufacturing (AM) has drawn tremendous attention in various fields. In recent years, great efforts have been made to develop novel additive manufacturing processes such as micro-/nano-scale 3D printing, bioprinting, and 4D printing for the fabrication of complex 3D structures with high resolution, living components, and multimaterials. The development of advanced functional materials is important for the implementation of these novel additive manufacturing processes. Here, a state-of-the-art review on advanced material strategies for novel additive manufacturing processes is provided, mainly including conductive materials, biomaterials, and smart materials. The advantages, limitations, and future perspectives of these materials for additive manufacturing are discussed. It is believed that the innovations of material strategies in parallel with the evolution of additive manufacturing processes will provide numerous possibilities for the fabrication of complex smart constructs with multiple functions, which will significantly widen the application fields of next-generation additive manufacturing.

Pressure activated interconnection of micro transfer printed components

NASA Astrophysics Data System (ADS)

Prevatte, Carl; Guven, Ibrahim; Ghosal, Kanchan; Gomez, David; Moore, Tanya; Bonafede, Salvatore; Raymond, Brook; Trindade, António Jose; Fecioru, Alin; Kneeburg, David; Meitl, Matthew A.; Bower, Christopher A.

2016-05-01

Micro transfer printing and other forms of micro assembly deterministically produce heterogeneously integrated systems of miniaturized components on non-native substrates. Most micro assembled systems include electrical interconnections to the miniaturized components, typically accomplished by metal wires formed on the non-native substrate after the assembly operation. An alternative scheme establishing interconnections during the assembly operation is a cost-effective manufacturing method for producing heterogeneous microsystems, and facilitates the repair of integrated microsystems, such as displays, by ex post facto addition of components to correct defects after system-level tests. This letter describes pressure-concentrating conductor structures formed on silicon (1 0 0) wafers to establish connections to preexisting conductive traces on glass and plastic substrates during micro transfer printing with an elastomer stamp. The pressure concentrators penetrate a polymer layer to form the connection, and reflow of the polymer layer bonds the components securely to the target substrate. The experimental yield of series-connected test systems with >1000 electrical connections demonstrates the suitability of the process for manufacturing, and robustness of the test systems against exposure to thermal shock, damp heat, and mechanical flexure shows reliability of the resulting bonds.

Review of Polyimides Used in the Manufacturing of Micro Systems

NASA Technical Reports Server (NTRS)

Wilson, William C.; Atkinson, Gary M.

2007-01-01

Since their invention, polyimides have found numerous uses in MicroElectroMechanical Systems (MEMS) technology. Polyimides can act as photoresist, sacrificial layers, structural layers, and even as a replacement for silicon as the substrate during MEMS fabrication. They enable fabrication of both low and high aspect ratio devices. Polyimides have been used to fabricate expendable molds and reusable flexible molds. Development of a variety of devices that employ polyimides for sensor applications has occurred. Micro-robotic actuator applications include hinges, thermal actuators and residual stress actuators. Currently, polyimides are being used to create new sensors and devices for aerospace applications. This paper presents a review of some of the many uses of polyimides in the development of MEMS devices, including a new polyimide based MEMS fabrication process.

Fabrication of micro-lens array on convex surface by meaning of micro-milling

NASA Astrophysics Data System (ADS)

Zhang, Peng; Du, Yunlong; Wang, Bo; Shan, Debin

2014-08-01

In order to develop the application of the micro-milling technology, and to fabricate ultra-precision optical surface with complex microstructure, in this paper, the primary experimental research on micro-milling complex microstructure array is carried out. A complex microstructure array surface with vary parameters is designed, and the mathematic model of the surface is set up and simulated. For the fabrication of the designed microstructure array surface, a micro three-axis ultra-precision milling machine tool is developed, aerostatic guideway drove directly by linear motor is adopted in order to guarantee the enough stiffness of the machine, and novel numerical control strategy with linear encoders of 5nm resolution used as the feedback of the control system is employed to ensure the extremely high motion control accuracy. With the help of CAD/CAM technology, convex micro lens array on convex spherical surface with different scales on material of polyvinyl chloride (PVC) and pure copper is fabricated using micro tungsten carbide ball end milling tool based on the ultra-precision micro-milling machine. Excellent nanometer-level micro-movement performance of the axis is proved by motion control experiment. The fabrication is nearly as the same as the design, the characteristic scale of the microstructure is less than 200μm and the accuracy is better than 1μm. It prove that ultra-precision micro-milling technology based on micro ultra-precision machine tool is a suitable and optional method for micro manufacture of microstructure array surface on different kinds of materials, and with the development of micro milling cutter, ultraprecision micro-milling complex microstructure surface will be achieved in future.

Demonstration of a large-size horizontal light-field display based on the LED panel and the micro-pinhole unit array

NASA Astrophysics Data System (ADS)

Yang, Le; Sang, Xinzhu; Yu, Xunbo; Liu, Boyang; Liu, Li; Yang, Shenwu; Yan, Binbin; Du, Jingyan; Gao, Chao

2018-05-01

A 54-inch horizontal-parallax only light-field display based on the light-emitting diode (LED) panel and the micro-pinhole unit array (MPUA) is demonstrated. Normally, the perceived 3D effect of the three-dimensional (3D) display with smooth motion parallax and abundant light-field information can be enhanced with increasing the density of viewpoints. However, the density of viewpoints is inversely proportional to the spatial display resolution for the conventional integral imaging. Here, a special MPUA is designed and fabricated, and the displayed 3D scene constructed by the proposed horizontal light-field display is presented. Compared with the conventional integral imaging, both the density of horizontal viewpoints and the spatial display resolution are significantly improved. In the experiment, A 54-inch horizontal light-field display with 42.8° viewing angle based on the LED panel with the resolution of 1280 × 720 and the MPUA is realized, which can provide natural 3D visual effect to observers with high quality.

Mechanics of additively manufactured biomaterials.

PubMed

Zadpoor, Amir A

2017-06-01

Additive manufacturing (3D printing) has found many applications in healthcare including fabrication of biomaterials as well as bioprinting of tissues and organs. Additively manufactured (AM) biomaterials may possess arbitrarily complex micro-architectures that give rise to novel mechanical, physical, and biological properties. The mechanical behavior of such porous biomaterials including their quasi-static mechanical properties and fatigue resistance is not yet well understood. It is particularly important to understand the relationship between the designed micro-architecture (topology) and the resulting mechanical properties. The current special issue is dedicated to understanding the mechanical behavior of AM biomaterials. Although various types of AM biomaterials are represented in the special issue, the primary focus is on AM porous metallic biomaterials. As a prelude to this special issue, this editorial reviews some of the latest findings in the mechanical behavior of AM porous metallic biomaterials so as to describe the current state-of-the-art and set the stage for the other studies appearing in the issue. Some areas that are important for future research are also briefly mentioned. Copyright © 2017 Elsevier Ltd. All rights reserved.

Numerical and experimental investigation of light trapping effect of nanostructured diatom frustules

NASA Astrophysics Data System (ADS)

Chen, Xiangfan; Wang, Chen; Baker, Evan; Sun, Cheng

2015-07-01

Recent advances in nanophotonic light-trapping technologies offer promising solutions in developing high-efficiency thin-film solar cells. However, the cost-effective scalable manufacturing of those rationally designed nanophotonic structures remains a critical challenge. In contrast, diatoms, the most common type of phytoplankton found in nature, may offer a very attractive solution. Diatoms exhibit high solar energy harvesting efficiency due to their frustules (i.e., hard porous cell wall made of silica) possessing remarkable hierarchical micro-/nano-scaled features optimized for the photosynthetic process through millions of years of evolution. Here we report numerical and experimental studies to investigate the light-trapping characteristic of diatom frustule. Rigorous coupled wave analysis (RCWA) and finite-difference time-domain (FDTD) methods are employed to investigate the light-trapping characteristics of the diatom frustules. In simulation, placing the diatom frustules on the surface of the light-absorption materials is found to strongly enhance the optical absorption over the visible spectrum. The absorption spectra are also measured experimentally and the results are in good agreement with numerical simulations.

PowerGuard® manufacturing innovation and expansion

NASA Astrophysics Data System (ADS)

Dinwoodie, Thomas; Kleiner, Tim; O'Brien, Colleen; Quiroz, Maurice

1999-03-01

PowerLight Corporation, with support from the DOE's PVMaT program, has undertaken a comprehensive agenda to automate the manufacture of its PowerGuard PV roof tile system. The advanced manufacturing will lead to substantially reduced costs, quality improvements, and increased production capacity. Over the three years of the PVMaT contract, system costs are expected to fall 2.65/Wp, with annual production capability increasing from 5 to 16 MW. PowerLight is on schedule with meeting its objectives under this program.

Micro optical sensor systems for sunsensing applications

NASA Astrophysics Data System (ADS)

Leijtens, Johan; de Boom, Kees

2017-11-01

Optimum application of micro system technologies allows building small sensor systems that will alter procurement strategies for spacecraft manufacturers. One example is the decreased size and cost for state of the art sunsensors. Integrated sensor systems are being designed which, through use of microsystem technology, are an order of magnitutde smaller than most current sunsensors and which hold due to the large reproducibility through batch manufacturing the promise of drastic price reduction. If the Commercial Of The Shelf (COTS) approach is adopted by satellite manufacturers, this will drastically decrease mass and cost budgets associated with sunsensing applications.

Pumping capacity and reliability of cryogenic micro-pump for micro-satellite applications

NASA Astrophysics Data System (ADS)

Zhang, Xin; Zhao, Yi; Li, Biao; Ludlow, Daryl

2004-10-01

In micro-satellites, delicate instruments are compacted into a limited space. This raises concerns of active cooling and remote cooling. Silicon based micro-pump arrays are employed thanks to manufacturing simplicity, a small cryogen charge, etc, and keep the instruments within a narrow cryogenic temperature range. The pumping capacity and reliability of the micro-pump are critical in terms of heat balance calculation and lifetime evaluation. The pumping capacity is associated with the diaphragm deflection while the reliability is associated with stress and fatigue. Both of them heavily depend on the silicon diaphragm, one of the key components. This paper examines the pumping capacity and reliability of the micro-pump under cryogenic temperature for micro-satellite applications. In this work, differential pressure was used for the actuation of a single-crystal silicon diaphragm. Diaphragm deflection and stress distribution were achieved using interferometry and micro-Raman spectroscopy, respectively. As a result, smaller pumping capacity was derived under cryogenic temperature, compared to that under room temperature, indicating a stiffer material. From stress mapping, the edge centers were believed to be the most vulnerable to fracture, which was further validated by analyzing the fracture diaphragm. Moreover, a fatigue testing was conducted for 1.8 million cycles with no damage found, verifying silicon as a viable material for long time operation in a cryogenic environment.

Micro-machined resonator oscillator

DOEpatents

Koehler, Dale R.; Sniegowski, Jeffry J.; Bivens, Hugh M.; Wessendorf, Kurt O.

1994-01-01

A micro-miniature resonator-oscillator is disclosed. Due to the miniaturization of the resonator-oscillator, oscillation frequencies of one MHz and higher are utilized. A thickness-mode quartz resonator housed in a micro-machined silicon package and operated as a "telemetered sensor beacon" that is, a digital, self-powered, remote, parameter measuring-transmitter in the FM-band. The resonator design uses trapped energy principles and temperature dependence methodology through crystal orientation control, with operation in the 20-100 MHz range. High volume batch-processing manufacturing is utilized, with package and resonator assembly at the wafer level. Unique design features include squeeze-film damping for robust vibration and shock performance, capacitive coupling through micro-machined diaphragms allowing resonator excitation at the package exterior, circuit integration and extremely small (0.1 in. square) dimensioning. A family of micro-miniature sensor beacons is also disclosed with widespread applications as bio-medical sensors, vehicle status monitors and high-volume animal identification and health sensors. The sensor family allows measurement of temperatures, chemicals, acceleration and pressure. A microphone and clock realization is also available.

Micro-machined resonator oscillator

DOEpatents

Koehler, D.R.; Sniegowski, J.J.; Bivens, H.M.; Wessendorf, K.O.

1994-08-16

A micro-miniature resonator-oscillator is disclosed. Due to the miniaturization of the resonator-oscillator, oscillation frequencies of one MHz and higher are utilized. A thickness-mode quartz resonator housed in a micro-machined silicon package and operated as a telemetered sensor beacon'' that is, a digital, self-powered, remote, parameter measuring-transmitter in the FM-band. The resonator design uses trapped energy principles and temperature dependence methodology through crystal orientation control, with operation in the 20--100 MHz range. High volume batch-processing manufacturing is utilized, with package and resonator assembly at the wafer level. Unique design features include squeeze-film damping for robust vibration and shock performance, capacitive coupling through micro-machined diaphragms allowing resonator excitation at the package exterior, circuit integration and extremely small (0.1 in. square) dimensioning. A family of micro-miniature sensor beacons is also disclosed with widespread applications as bio-medical sensors, vehicle status monitors and high-volume animal identification and health sensors. The sensor family allows measurement of temperatures, chemicals, acceleration and pressure. A microphone and clock realization is also available. 21 figs.

A process to control light in a micro resonator through a coupling modulation by surface acoustic waves

NASA Astrophysics Data System (ADS)

Fan, Guofang; Li, Yuan; Hu, Chunguang; Lei, Lihua; Guo, Yanchuan

2016-08-01

A novel process to control light through the coupling modulation by surface acoustic wave (SAW) is presented in an optical micro resonator. An optical waveguide modulator of a racetrack resonator on silicon-on-insulator (SOI) technology is took as an example to explore the mechanism. A finite-difference time-domain (FDTD) is developed to simulate the acousto-optical (AO) modulator using the mechanism. An analytical method is presented to verify our proposal. The results show that the process can work well as an optical modulator by SAW.

No-Light Light Bulbs

ERIC Educational Resources Information Center

Modern Schools, 1976

1976-01-01

A thumbnail sketch of some of the light bulbs manufactured for a purpose other than seeing. These "dark" lamps perform varied tasks including keeping food fresh, detecting and preventing disease, spurring plant growth, heating, and copying printed material. (Author/MLF)

Using Innovative Technologies for Manufacturing and Evaluating Rocket Engine Hardware

NASA Technical Reports Server (NTRS)

Betts, Erin M.; Hardin, Andy

2011-01-01

Many of the manufacturing and evaluation techniques that are currently used for rocket engine component production are traditional methods that have been proven through years of experience and historical precedence. As we enter into a new space age where new launch vehicles are being designed and propulsion systems are being improved upon, it is sometimes necessary to adopt new and innovative techniques for manufacturing and evaluating hardware. With a heavy emphasis on cost reduction and improvements in manufacturing time, manufacturing techniques such as Direct Metal Laser Sintering (DMLS) and white light scanning are being adopted and evaluated for their use on J-2X, with hopes of employing both technologies on a wide variety of future projects. DMLS has the potential to significantly reduce the processing time and cost of engine hardware, while achieving desirable material properties by using a layered powdered metal manufacturing process in order to produce complex part geometries. The white light technique is a non-invasive method that can be used to inspect for geometric feature alignment. Both the DMLS manufacturing method and the white light scanning technique have proven to be viable options for manufacturing and evaluating rocket engine hardware, and further development and use of these techniques is recommended.

High strength fused silica flexures manufactured by femtosecond laser

NASA Astrophysics Data System (ADS)

Bellouard, Yves; Said, Ali A.; Dugan, Mark; Bado, Philippe

2009-02-01

Flexures are mechanical elements used in micro- and precision-engineering to precisely guide the motion of micro-parts. They consist of slender bodies that deform elastically upon the application of a force. Although counter-intuitive at first, fused silica is an attractive material for flexure. Pending that the machining process does not introduce surface flaws that would lead to catastrophic failure, the material has a theoretically high ultimate tensile strength of several GPa. We report on high-aspect ratio fused silica flexures manufactured by femtosecond laser combined with chemical etching. Notch-hinges with thickness as small as twenty microns and aspect ratios comparable to aspect ratios obtained by Deep- Reactive-Ion-Etching (DRIE) were fabricated and tested under different loading conditions. Multiple fracture tests were performed for various loading conditions and the cracks morphologies were analyzed using Scanning Electron Microscopy. The manufactured elements show outstanding mechanical properties with flexural strengths largely exceeding those obtained with other technologies and materials. Fused silica flexures offer a mean to combine integrated optics with micro-mechanics in a single monolithic substrate. Waveguides and mechanical elements can be combined in a monolithic devices opening new opportunities for integrated opto-mechatronics devices.

49 CFR 579.27 - Reporting requirements for manufacturers of fewer than 100 buses annually, for manufacturers of...

Code of Federal Regulations, 2010 CFR

2010-10-01

... manufacturers of fewer than 5,000 light vehicles, medium-heavy vehicles (other than buses and emergency vehicles... fewer than 5,000 light vehicles, medium-heavy vehicles (other than buses and emergency vehicles... vehicles, medium-heavy vehicles and buses, motorcycles, or trailers submitted pursuant to §§ 579.21 through...

Micro-optofluidic Lenses: A review

PubMed Central

Nguyen, Nam-Trung

2010-01-01

This review presents a systematic perspective on the development of micro-optofluidic lenses. The progress on the development of micro-optofluidic lenses are illustrated by example from recent literature. The advantage of micro-optofluidic lenses over solid lens systems is their tunability without the use of large actuators such as servo motors. Depending on the relative orientation of light path and the substrate surface, micro-optofluidic lenses can be categorized as in-plane or out-of-plane lenses. However, this review will focus on the tunability of the lenses and categorizes them according to the concept of tunability. Micro-optofluidic lenses can be either tuned by the liquid in use or by the shape of the lens. Micro-optofluidic lenses with tunable shape are categorized according to the actuation schemes. Typical parameters of micro-optofluidic lenses reported recently are compared and discussed. Finally, perspectives are given for future works in this field. PMID:20714369

Effective Light Directed Assembly of Building Blocks with Microscale Control.

PubMed

Dinh, Ngoc-Duy; Luo, Rongcong; Christine, Maria Tankeh Asuncion; Lin, Weikang Nicholas; Shih, Wei-Chuan; Goh, James Cho-Hong; Chen, Chia-Hung

2017-06-01

Light-directed forces have been widely used to pattern micro/nanoscale objects with precise control, forming functional assemblies. However, a substantial laser intensity is required to generate sufficient optical gradient forces to move a small object in a certain direction, causing limited throughput for applications. A high-throughput light-directed assembly is demonstrated as a printing technology by introducing gold nanorods to induce thermal convection flows that move microparticles (diameter = 40 µm to several hundreds of micrometers) to specific light-guided locations, forming desired patterns. With the advantage of effective light-directed assembly, the microfluidic-fabricated monodispersed biocompatible microparticles are used as building blocks to construct a structured assembly (≈10 cm scale) in ≈2 min. The control with microscale precision is approached by changing the size of the laser light spot. After crosslinking assembly of building blocks, a novel soft material with wanted pattern is approached. To demonstrate its application, the mesenchymal stem-cell-seeded hydrogel microparticles are prepared as functional building blocks to construct scaffold-free tissues with desired structures. This light-directed fabrication method can be applied to integrate different building units, enabling the bottom-up formation of materials with precise control over their internal structure for bioprinting, tissue engineering, and advanced manufacturing. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Improving the -3 dB bandwidth of medium power GaN-based LEDs through periodic micro via-holes for visible light communications

NASA Astrophysics Data System (ADS)

Zhou, Zheng; Yan, Bing; Teng, Dongdong; Liu, Lilin; Wang, Gang

2017-06-01

Medium power GaN-based light emitting diode (LED) chips with periodic micro via-holes are designed and fabricated. The active area of each chip is 200 μm×800 μm and the diameter of each micro via-hole is 50 μm. For comparison, an LED chip with only one big via-hole (Diameter=86.6 μm) is also fabricated under the same conditions as the control partner. Both kinds of LED chips have an equal effective PN junction area. Experimentally, the LED with periodic via-holes exhibits higher output optical power and the -3 dB modulation bandwidth by about 33% and 48%, respectively, than the LED with only one bigger via-hole. The method of concurrently improving modulation and optical performances of power-type LED chips through periodic micro via-holes take the advantages of easy fabrication, suitable for mass-production.

Collection, Measurement and Treatment of Microorganism Using Dielectrophoretic Micro Devices

NASA Astrophysics Data System (ADS)

Uchida, Satoshi

Constant monitoring of manufacturing processes has been essential in food industry because of global expansion of microbial infection. Micro-scale dielectrophoretic method is an attractive technique for direct operation and quantitative detection of bioparticles. The electrical system is capable of rapid and simple treatments corresponding to severe legal control for food safety. In this paper, newly developed techniques are reviewed for bacterial concentration, detection and sterilization using dielectrophoresis in a micro reactor. The perspective to an integrated micro device of those components is also discussed.

Methods for fabricating a micro heat barrier

DOEpatents

Marshall, Albert C.; Kravitz, Stanley H.; Tigges, Chris P.; Vawter, Gregory A.

2004-01-06

Methods for fabricating a highly effective, micron-scale micro heat barrier structure and process for manufacturing a micro heat barrier based on semiconductor and/or MEMS fabrication techniques. The micro heat barrier has an array of non-metallic, freestanding microsupports with a height less than 100 microns, attached to a substrate. An infrared reflective membrane (e.g., 1 micron gold) can be supported by the array of microsupports to provide radiation shielding. The micro heat barrier can be evacuated to eliminate gas phase heat conduction and convection. Semi-isotropic, reactive ion plasma etching can be used to create a microspike having a cusp-like shape with a sharp, pointed tip (<0.1 micron), to minimize the tip's contact area. A heat source can be placed directly on the microspikes. The micro heat barrier can have an apparent thermal conductivity in the range of 10.sup.-6 to 10.sup.-7 W/m-K. Multiple layers of reflective membranes can be used to increase thermal resistance.

Electrochemical micro/nano-machining: principles and practices.

PubMed

Zhan, Dongping; Han, Lianhuan; Zhang, Jie; He, Quanfeng; Tian, Zhao-Wu; Tian, Zhong-Qun

2017-03-06

Micro/nano-machining (MNM) is becoming the cutting-edge of high-tech manufacturing because of the increasing industrial demand for supersmooth surfaces and functional three-dimensional micro/nano-structures (3D-MNS) in ultra-large scale integrated circuits, microelectromechanical systems, miniaturized total analysis systems, precision optics, and so on. Taking advantage of no tool wear, no surface stress, environmental friendliness, simple operation, and low cost, electrochemical micro/nano-machining (EC-MNM) has an irreplaceable role in MNM. This comprehensive review presents the state-of-art of EC-MNM techniques for direct writing, surface planarization and polishing, and 3D-MNS fabrications. The key point of EC-MNM is to confine electrochemical reactions at the micro/nano-meter scale. This review will bring together various solutions to "confined reaction" ranging from electrochemical principles through technical characteristics to relevant applications.

Selective Photophysical Modification on Light-Emitting Polymer Films for Micro- and Nano-Patterning

PubMed Central

Zhang, Xinping; Liu, Feifei; Li, Hongwei

2016-01-01

Laser-induced cross-linking in polymeric semiconductors was utilized to achieve micro- and nano-structuring in thin films. Single- and two-photon cross-linking processes led to the reduction in both the refractive index and thickness of the polymer films. The resultant photonic structures combine the features of both relief- and phase-gratings. Selective cross-linking in polymer blend films based on different optical response of different molecular phases enabled “solidification” of the phase-separation scheme, providing a stable template for further photonic structuring. Dielectric and metallic structures are demonstrated for the fabrication methods using cross-linking in polymer films. Selective cross-linking enables direct patterning into polymer films without introducing additional fabrication procedures or additional materials. The diffraction processes of the emission of the patterned polymeric semiconductors may provide enhanced output coupling for light-emitting diodes or distributed feedback for lasers. PMID:28773248

Plant lighting system with five wavelength-band light-emitting diodes providing photon flux density and mixing ratio control

PubMed Central

2012-01-01

Background Plant growth and development depend on the availability of light. Lighting systems therefore play crucial roles in plant studies. Recent advancements of light-emitting diode (LED) technologies provide abundant opportunities to study various plant light responses. The LED merits include solidity, longevity, small element volume, radiant flux controllability, and monochromaticity. To apply these merits in plant light response studies, a lighting system must provide precisely controlled light spectra that are useful for inducing various plant responses. Results We have developed a plant lighting system that irradiated a 0.18 m2 area with a highly uniform distribution of photon flux density (PFD). The average photosynthetic PFD (PPFD) in the irradiated area was 438 micro-mol m–2 s–1 (coefficient of variation 9.6%), which is appropriate for growing leafy vegetables. The irradiated light includes violet, blue, orange-red, red, and far-red wavelength bands created by LEDs of five types. The PFD and mixing ratio of the five wavelength-band lights are controllable using a computer and drive circuits. The phototropic response of oat coleoptiles was investigated to evaluate plant sensitivity to the light control quality of the lighting system. Oat coleoptiles irradiated for 23 h with a uniformly distributed spectral PFD (SPFD) of 1 micro-mol m–2 s–1 nm–1 at every peak wavelength (405, 460, 630, 660, and 735 nm) grew almost straight upwards. When they were irradiated with an SPFD gradient of blue light (460 nm peak wavelength), the coleoptiles showed a phototropic curvature in the direction of the greater SPFD of blue light. The greater SPFD gradient induced the greater curvature of coleoptiles. The relation between the phototropic curvature (deg) and the blue-light SPFD gradient (micro-mol m–2 s–1 nm–1 m–1) was 2 deg per 1 micro-mol m–2 s–1 nm–1 m–1. Conclusions The plant lighting system, with a computer with a graphical user interface

Spectroscopy of scattered light for the characterization of micro and nanoscale objects in biology and medicine.

PubMed

Turzhitsky, Vladimir; Qiu, Le; Itzkan, Irving; Novikov, Andrei A; Kotelev, Mikhail S; Getmanskiy, Michael; Vinokurov, Vladimir A; Muradov, Alexander V; Perelman, Lev T

2014-01-01

The biomedical uses for the spectroscopy of scattered light by micro and nanoscale objects can broadly be classified into two areas. The first, often called light scattering spectroscopy (LSS), deals with light scattered by dielectric particles, such as cellular and sub-cellular organelles, and is employed to measure their size or other physical characteristics. Examples include the use of LSS to measure the size distributions of nuclei or mitochondria. The native contrast that is achieved with LSS can serve as a non-invasive diagnostic and scientific tool. The other area for the use of the spectroscopy of scattered light in biology and medicine involves using conducting metal nanoparticles to obtain either contrast or electric field enhancement through the effect of the surface plasmon resonance (SPR). Gold and silver metal nanoparticles are non-toxic, they do not photobleach, are relatively inexpensive, are wavelength-tunable, and can be labeled with antibodies. This makes them very promising candidates for spectrally encoded molecular imaging. Metal nanoparticles can also serve as electric field enhancers of Raman signals. Surface enhanced Raman spectroscopy (SERS) is a powerful method for detecting and identifying molecules down to single molecule concentrations. In this review, we will concentrate on the common physical principles, which allow one to understand these apparently different areas using similar physical and mathematical approaches. We will also describe the major advancements in each of these areas, as well as some of the exciting recent developments.

Micro Ring Grating Spectrometer with Adjustable Aperture

NASA Technical Reports Server (NTRS)

Park, Yeonjoon (Inventor); King, Glen C. (Inventor); Elliott, James R. (Inventor); Choi, Sang H. (Inventor)

2012-01-01

A spectrometer includes a micro-ring grating device having coaxially-aligned ring gratings for diffracting incident light onto a target focal point, a detection device for detecting light intensity, one or more actuators, and an adjustable aperture device defining a circular aperture. The aperture circumscribes a target focal point, and directs a light to the detection device. The aperture device is selectively adjustable using the actuators to select a portion of a frequency band for transmission to the detection device. A method of detecting intensity of a selected band of incident light includes directing incident light onto coaxially-aligned ring gratings of a micro-ring grating device, and diffracting the selected band onto a target focal point using the ring gratings. The method includes using an actuator to adjust an aperture device and pass a selected portion of the frequency band to a detection device for measuring the intensity of the selected portion.

Additive Manufacturing Infrared Inspection

NASA Technical Reports Server (NTRS)

Gaddy, Darrell

2014-01-01

Additive manufacturing is a rapid prototyping technology that allows parts to be built in a series of thin layers from plastic, ceramics, and metallics. Metallic additive manufacturing is an emerging form of rapid prototyping that allows complex structures to be built using various metallic powders. Significant time and cost savings have also been observed using the metallic additive manufacturing compared with traditional techniques. Development of the metallic additive manufacturing technology has advanced significantly over the last decade, although many of the techniques to inspect parts made from these processes have not advanced significantly or have limitations. Several external geometry inspection techniques exist such as Coordinate Measurement Machines (CMM), Laser Scanners, Structured Light Scanning Systems, or even traditional calipers and gages. All of the aforementioned techniques are limited to external geometry and contours or must use a contact probe to inspect limited internal dimensions. This presentation will document the development of a process for real-time dimensional inspection technique and digital quality record of the additive manufacturing process using Infrared camera imaging and processing techniques.

NextFlex Flexible Hybrid Electronics Manufacturing

DTIC Science & Technology

2016-10-01

Defense AT&L: September-October 2016 32 ADVANCED MANUFACTURING N NextFlex Flexible Hybrid Electronics Manufacturing Eric Forsythe, Ph.D.  Benjamin...New York, in both Physics and Chemistry, where he worked on electronic interfaces and carrier transport in organic light-emitting devices in...Ohio. extFlex, America’s Flexible Hybrid Electronics Manu- facturing Innovation Institute, is a program formed out of a cooperative agreement awarded

Micro Computer Tomography for medical device and pharmaceutical packaging analysis.

PubMed

Hindelang, Florine; Zurbach, Raphael; Roggo, Yves

2015-04-10

Biomedical device and medicine product manufacturing are long processes facing global competition. As technology evolves with time, the level of quality, safety and reliability increases simultaneously. Micro Computer Tomography (Micro CT) is a tool allowing a deep investigation of products: it can contribute to quality improvement. This article presents the numerous applications of Micro CT for medical device and pharmaceutical packaging analysis. The samples investigated confirmed CT suitability for verification of integrity, measurements and defect detections in a non-destructive manner. Copyright © 2015 Elsevier B.V. All rights reserved.

Direct printing of micro/nanostructures by femtosecond laser excitation of nanocrystals

NASA Astrophysics Data System (ADS)

Shou, Wan; Pan, Heng

2017-02-01

Direct writing using single or multiple energized beams (e.g. laser, ion or electron beams) provides high feature resolution (<1μm) compared with other solution-based printing methods (e.g. inkjet printing). There have been extensive researches on micro/nano additive manufacturing methods employing laser (or optical) and ion/electron beams. Many of these processes utilize specially designed photosensitive materials consisting of additives and effective components. Due to the presence of additive (such as polymer and binders), the effective components are relatively low resulting in high threshold for device operation. In order to direct print functional devices at low cost, there has been extensive research on laser processing of pre-synthesized nanomaterials for non-polymer functional device manufacturing. Pre-synthesized nanocrystals can have better control in the stoichiometry and crystallinity. In addition, pre-synthesis process enjoys the flexibility in material choice since a variety of materials can be synthesized. Femtosecond laser assembly and deposition of nanomaterials can be a feasible 3D micro/nano additive manufacturing approach, although mechanisms leading to assembly and deposition have not been fully understood. In this paper, we propose a mechanism for 2D and 3D deposition of nanocrystals by laser excitation with moderate peak intensities(1011-1012 W/cm2). It is postulated that laser induced charging is responsible for the deposition. The scheme paves the way for laser selective electrophoretic deposition as a micro/nanoscale additive manufacturing approach.

Quantitative Analysis of Milk-Derived microRNAs and Microbiota during the Manufacturing and Ripening of Soft Cheese.

PubMed

Oh, Sangnam; Park, Mi-Ri; Ryu, Sangdon; Maburutse, Brighton; Kim, Ji-Uk; Kim, Younghoon

2017-09-28

MicroRNAs (miRNAs) are abundant in bovine milk and milk derived from other livestock, and they have functional roles in infants and in the secretion process of mammary glands. However, few studies have evaluated miRNAs in dairy processes, such as during cheese making and ripening. Thus, we investigated the characteristics of milk-derived miRNAs during the manufacturing and ripening of Camembert cheese as well as the microbiota present using the quantitative reverse transcription polymer chain reaction (RT-qPCR) and 16S rRNA pyrosequencing, respectively. Pyrosequencing showed that the cheese microbiota changed dramatically during cheese processing, including during the pasteurization, starter culture, and ripening stages. Our results indicated that the RNA contents per 200 mg/200 μl of the sample increased significantly during cheese-making and ripening. The inner cheese fractions had higher RNA contents than the surfaces after 12 and 22 days of ripening in a timedependent manner (21.9 and 13.2 times higher in the inner and surface fractions than raw milk, respectively). We performed a comparative analysis of the miRNAs in each fraction by RT-qPCR. Large amounts of miRNAs ( miR-93, miR-106a, miR-130, miR-155, miR-181a , and miR- 223 ) correlated with immune responses and mammary glands were present in aged cheese, with the exception of miR-223 , which was not present on the surface. Considerable amounts of miRNAs were also detected in whey, which is usually disposed of during the cheese-making process. Unexpectedly, there were no significant correlations between immune-related miRNAs and the microbial populations during cheese processing. Taken together, these results show that various functional miRNAs are present in cheese during its manufacture and that they are dramatically increased in amount in ripened Camembert cheese, with differences according to depth.

A correlative approach for combining microCT, light and transmission electron microscopy in a single 3D scenario

PubMed Central

2013-01-01

Background In biomedical research, a huge variety of different techniques is currently available for the structural examination of small specimens, including conventional light microscopy (LM), transmission electron microscopy (TEM), confocal laser scanning microscopy (CLSM), microscopic X-ray computed tomography (microCT), and many others. Since every imaging method is physically limited by certain parameters, a correlative use of complementary methods often yields a significant broader range of information. Here we demonstrate the advantages of the correlative use of microCT, light microscopy, and transmission electron microscopy for the analysis of small biological samples. Results We used a small juvenile bivalve mollusc (Mytilus galloprovincialis, approximately 0.8 mm length) to demonstrate the workflow of a correlative examination by microCT, LM serial section analysis, and TEM-re-sectioning. Initially these three datasets were analyzed separately, and subsequently they were fused in one 3D scene. This workflow is very straightforward. The specimen was processed as usual for transmission electron microscopy including post-fixation in osmium tetroxide and embedding in epoxy resin. Subsequently it was imaged with microCT. Post-fixation in osmium tetroxide yielded sufficient X-ray contrast for microCT imaging, since the X-ray absorption of epoxy resin is low. Thereafter, the same specimen was serially sectioned for LM investigation. The serial section images were aligned and specific organ systems were reconstructed based on manual segmentation and surface rendering. According to the region of interest (ROI), specific LM sections were detached from the slides, re-mounted on resin blocks and re-sectioned (ultrathin) for TEM. For analysis, image data from the three different modalities was co-registered into a single 3D scene using the software AMIRA®. We were able to register both the LM section series volume and TEM slices neatly to the microCT dataset, with

Measures of International Manufacturing and Trade of Clean Energy Technologies

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

Engel-Cox, Jill; Sandor, Debbie; Keyser, David

The technologies that produce clean energy, such as solar photovoltaic panels and lithium ion batteries for electric vehicles, are globally manufactured and traded. As demand and deployment of these technologies grows exponentially, the innovation to reach significant economies of scale and drive down energy production costs becomes less in the technology and more in the manufacturing of the technology. Manufacturing innovations and other manufacturing decisions can reduce costs of labor, materials, equipment, operating costs, and transportation, across all the links in the supply chain. To better understand the manufacturing aspect of the clean energy economy, we have developed key metricsmore » for systematically measuring and benchmarking international manufacturing of clean energy technologies. The metrics are: trade, market size, manufacturing value-added, and manufacturing capacity and production. These metrics were applied to twelve global economies and four representative technologies: wind turbine components, crystalline silicon solar photovoltaic modules, vehicle lithium ion battery cells, and light emitting diode packages for efficient lighting and other consumer products. The results indicated that clean energy technologies are being developed via complex, dynamic, and global supply chains, with individual economies benefiting from different technologies and links in the supply chain, through both domestic manufacturing and global trade.« less

Additively Manufactured Macroporous Titanium with Silver-Releasing Micro-/Nanoporous Surface for Multipurpose Infection Control and Bone Repair - A Proof of Concept.

PubMed

Jia, Zhaojun; Xiu, Peng; Xiong, Pan; Zhou, Wenhao; Cheng, Yan; Wei, Shicheng; Zheng, Yufeng; Xi, Tingfei; Cai, Hong; Liu, Zhongjun; Wang, Caimei; Zhang, Weiping; Li, Zhijiang

2016-10-26

Restoring large-scale bone defects, where osteogenesis is slow while infections lurk, with biomaterials represents a formidable challenge in orthopedic clinics. Here, we propose a scaffold-based multipurpose anti-infection and bone repairing strategy to meet such restorative needs. To do this, personalized multifunctional titanium meshes were produced through an advanced additive manufacturing process and dual "TiO 2 -poly(dopamine)/Ag (nano)" post modifications, yielding macroporous constructs with micro-/nanoporous walls and nanosilver bullets immobilized/embedded therein. Ultrahigh loading capacity and durable release of Ag + were accomplished. The scaffolds were active against planktonic/adherent bacteria (Gram-negative and positive) for up to 12 weeks. Additionally, they not only defended themselves from biofilm colonization but also helped destroy existing biofilms, especially in combination with antibiotics. Further, the osteoblasts/bacteria coculture study displayed that the engineered surfaces aided MG-63 cells to combat bacterial invasion. Meanwhile, the scaffolds elicited generally acceptable biocompatibility (cell adhesion, proliferation, and viability) and hastened osteoblast differentiation and maturation (alkaline phosphatase production, matrix secretion, and calcification), by synergy of micro-/nanoscale topological cues and bioactive catecholamine chemistry. Although done ex vivo, these studies reveal that our three-in-one strategy (infection prophylaxis, infection fighting, and bone repair) has great potential to simultaneously prevent/combat infections and bridge defected bone. This work provides new thoughts to the use of enabling technologies to design biomaterials that resolve unmet clinical needs.

Micro-light-emitting diodes with III-nitride tunnel junction contacts grown by metalorganic chemical vapor deposition

NASA Astrophysics Data System (ADS)

Hwang, David; Mughal, Asad J.; Wong, Matthew S.; Alhassan, Abdullah I.; Nakamura, Shuji; DenBaars, Steven P.

2018-01-01

Micro-light-emitting diodes (µLEDs) with tunnel junction (TJ) contacts were grown entirely by metalorganic chemical vapor deposition. A LED structure was grown, treated with UV ozone and hydrofluoric acid, and reloaded into the reactor for TJ regrowth. The silicon doping level of the n++-GaN TJ was varied to examine its effect on voltage. µLEDs from 2.5 × 10-5 to 0.01 mm2 in area were processed, and the voltage penalty of the TJ for the smallest µLED at 20 A/cm2 was 0.60 V relative to that for a standard LED with indium tin oxide. The peak external quantum efficiency of the TJ LED was 34%.

The study of LED light source illumination conditions for ideal algae cultivation

NASA Astrophysics Data System (ADS)

Tsai, Chun-Chin; Huang, Chien-Fu; Chen, Cin-Fu; Yue, Cheng-Feng

2017-02-01

Utilizing LED light source modules with 3 different RGB colors, the illumination effect of different wavelengths had been investigated on the growth curve of the same kind of micro algae. It was found that the best micro algae culturing status came out with long wavelength light such as red light (650 670 nm). Based on the same condition for a period of 3 weeks , the grown micro algae population density ratio represented by Optical Density (O.D.) ratio is 1?0.4?0.7 corresponding to growth with Red, Green, Blue light sources, respectively. Mixing 3 types and 2 types of LEDs with different parameters, the grown micro algae population densities were compared in terms of O.D. Interestingly enough, different light sources resulted in significant discoloration on micro algae growth, appearing yellow, brown, green, etc. Our experiments results showed such discoloration effect is reversible. Based on the same lighting condition, micro algae growth can be also affected by incubator size, nutrition supply, and temperature variation. In recent years, micro algae related technologies have been international wise a hot topic of energy and environmental protection for research and development institutes, and big energy companies among those developed countries. There will be an economically prosperous future. From this study of LED lighting to ideal algae cultivation, it was found that such built system would be capable of optimizing artificial cultivation system, leading to economic benefits for its continuous development. Since global warming causing weather change, accompanying with reducing energy sources and agriculture growth shortage are all threatening human being survival.

Filling of high aspect ratio micro features of a microfluidic flow cytometer chip using micro injection moulding

NASA Astrophysics Data System (ADS)

Zhang, Haoyang; Fang, Fengzhou; Gilchrist, Michael D.; Zhang, Nan

2018-07-01

Micro injection moulding has been demonstrated as one of the most efficient mass production technologies for manufacturing polymeric microfluidic devices, which have been widely used in life sciences, environmental and analytical fields and agro-food industries. However, the filling of micro features for typical microfluidic devices is complicated and not yet fully understood, which consequently restricts the chip development. In the present work, a microfluidic flow cytometer chip with essential high aspect ratio micro features was used as a typical model to study their filling process. Short-shot experiments and single factor experiments were performed to examine the filling progress of such features during the injection and packing stages of the micro injection moulding process. The influence of process parameters such as shot size, packing pressure, packing time and mould temperature were systematically monitored, characterised and correlated with 3D measurements and real response of the machine such as screw velocity and screw position. A combined melt flow and creep deformation model was proposed to explain the complex influence of process on replication. An approach of over-shot micro injection moulding was proposed and was shown to be effective at improving the replication quality of high aspect ratio micro features.

Particle detection for patterned wafers of 100nm design rule by evanescent light illumination: analysis of evanescent light scattering using Finite-Difference Time-Domain (FDTD) method

NASA Astrophysics Data System (ADS)

Yoshioka, Toshie; Miyoshi, Takashi; Takaya, Yasuhiro

2005-12-01

To realize high productivity and reliability of the semiconductor, patterned wafers inspection technology to maintain high yield becomes essential in modern semiconductor manufacturing processes. As circuit feature is scaled below 100nm, the conventional imaging and light scattering methods are impossible to apply to the patterned wafers inspection technique, because of diffraction limit and lower S/N ratio. So, we propose a new particle detection method using annular evanescent light illumination. In this method, a converging annular light used as a light source is incident on a micro-hemispherical lens. When the converging angle is larger than critical angle, annular evanescent light is generated under the bottom surface of the hemispherical lens. Evanescent light is localized near by the bottom surface and decays exponentially away from the bottom surface. So, the evanescent light selectively illuminates the particles on the patterned wafer surface, because it can't illuminate the patterned wafer surface. The proposed method evaluates particles on a patterned wafer surface by detecting scattered evanescent light distribution from particles. To analyze the fundamental characteristics of the proposed method, the computer simulation was performed using FDTD method. The simulation results show that the proposed method is effective for detecting 100nm size particle on patterned wafer of 100nm lines and spaces, particularly under the condition that the evanescent light illumination with p-polarization and parallel incident to the line orientation. Finally, the experiment results suggest that 220nm size particle on patterned wafer of about 200nm lines and spaces can be detected.

Effect of manufacturing defects on optical performance of discontinuous freeform lenses.

PubMed

Wang, Kai; Liu, Sheng; Chen, Fei; Liu, Zongyuan; Luo, Xiaobing

2009-03-30

Discontinuous freeform lens based secondary optics are essential to LED illumination systems. Surface roughness and smooth transition between two discrete sub-surfaces are two of the most common manufacturing defects existing in discontinuous freeform lenses. The effects of these two manufacturing defects on the optical performance of two discontinuous freeform lenses were investigated by comparing the experimental results with the numerical simulation results based on Monte Carlo ray trace method. The results demonstrated that manufacturing defects induced surface roughness had small effect on the light output efficiency and the shape of light pattern of the PMMA lens but significantly affected the uniformity of light pattern, which declined from 0.644 to 0.313. The smooth transition surfaces with deviation angle more than 60 degrees existing in the BK7 glass lens, not only reduced the uniformity of light pattern, but also reduced the light output efficiency from 96.9% to 91.0% and heavily deformed the shape of the light pattern. Comparing with the surface roughness, the smooth transition surface had a much more adverse effect on the optical performance of discontinuous freeform lenses. Three methods were suggested to improve the illumination performance according to the analysis and discussion.

Beyond spatial correlation effect in micro-Raman light scattering: An example of zinc-blende GaN/GaAs hetero-interface

NASA Astrophysics Data System (ADS)

Ning, J. Q.; Zheng, C. C.; Zheng, L. X.; Xu, S. J.

2015-08-01

Spatially resolved Raman light scattering experiments were performed on a zinc-blende GaN/GaAs heterostructure with confocal micro-Raman scattering technique under the backscattering geometric configuration. By varying the illumination spot locations across the heterostructure interface, we found that the Raman light scattering spectral features change remarkably. The interface effect on the GaAs substrate manifested as a much broader lineshape of the transverse optical (TO) phonon mode. Two kinds of broadening mechanisms, namely, spatial correlation induced wave-vector relaxation effect and lattice-mismatch strain + compositional intermixing effect, have been identified. The former leads to the broadening of the TO mode at the low-energy side, whereas the latter accounts for the broadening at the high-energy side. The diffuse light scattering from the highly defective nucleation layer of GaN was found to produce a broad scattering background of the GaN TO mode. The methodology and conclusions of the present work could be applicable to Raman spectroscopic studies on other material interfaces.

Mini and micro spectrometers pave the way to on-field advanced analytics

NASA Astrophysics Data System (ADS)

Bouyé, Clémentine; Kolb, Hugo; d'Humières, Benoît.

2016-03-01

First introduced in the 1990's, miniature optical spectrometers were compact, portable devices brought on the market by the desire to move from time-consuming lab-based analyses to on-field and in situ measurements. This goal of getting spectroscopy into the hands of non-specialists is driving current technical and application developments, the ultimate goal being, in a far future, the integration of a spectrometer into a smartphone or any other smart device (tablet, watch, …). In this article, we present the results of our study on the evolution of the compact spectrometers market towards widespread industrial use and consumer applications. Presently, the main market of compact spectrometers remains academic labs. However, they have been adopted on some industrial applications such as optical source characterization (mainly laser and LEDs). In a near future, manufacturers of compact spectrometers target the following industrial applications: agriculture crop monitoring, food process control or pharmaceuticals quality control. Next steps will be to get closer to the consumer market with point-of-care applications such as glucose detection for diabetics, for example. To reach these objectives, technological breakthroughs will be necessary. Recent progresses have already allowed the release of micro-spectrometers. They take advantage of new micro-technologies such as MEMS (MicroElectroMechanical Systems), MOEMS (Micro-Opto-Electro-Mechanical Systems), micro-mirrors arrays to reduce cost and size while allowing good performance and high volume manufacturability. Integrated photonics is being investigated for future developments. It will also require new business models and new market approaches. Indeed, spreading spectroscopy to more industrial and consumer applications will require spectrometers manufacturers to get closer to the end-users and develop application-oriented products.

Signal lights - designed light for rear lamps and new upcoming technologies: innovations in automotive lighting

NASA Astrophysics Data System (ADS)

Mügge, Martin; Hohmann, Carsten

2016-04-01

Signal functions have to fulfill statutory regulations such as ECE or FMVSS108 to provide a clear signal to other road users and satisfy the same standard definitions of lighting parameters. However, as rear combination lamps are very different from one another, and these days are an increasingly powerful design element of cars, automotive manufacturers want an innovative, superior, and contrasting design. Daytime appearances with a new and unusual look and nighttime appearances with unexpected illumination are strong drivers for developing amazing innovative signal functions. The combination of LED technology and different forms of light-guiding optics, new interpretations of common optical systems to develop various styling options, the use of new materials and components for lighting effects, the introduction of OLED technology on the automotive market, and amazing new optical systems, using diffractive or holographic optics in future rear lamps, are paving the way for further, exciting design possibilities. The challenge of new signal functions is to take these possibilities and to develop the appearance and illumination effects the designer wants to reinforce the image of the car manufacturer and to fit harmoniously into the vehicle design. Lighting systems with a three-dimensional design and appearance when unlit and lit, amazing 3D effects, and surprising lighting scenarios will gain in importance. But the signal lights on cars will, in the future, be not only lighting functions in rear lamps; new functions and stylistic illuminations for coming/leaving-home scenarios will support and complete the car's overall lighting appearance. This paper describes current lighting systems realizing the styling requirements and future lighting systems offering new design possibilities and developing further stylistic, visual effects and improved technologies.

3D printing of nano- and micro-structures

NASA Astrophysics Data System (ADS)

Ramasamy, Mouli; Varadan, Vijay K.

2016-04-01

Additive manufacturing or 3D printing techniques are being vigorously investigated as a replacement to the traditional and conventional methods in fabrication to bring forth cost and time effective approaches. Introduction of 3D printing has led to printing micro and nanoscale structures including tissues and organelles, bioelectric sensors and devices, artificial bones and transplants, microfluidic devices, batteries and various other biomaterials. Various microfabrication processes have been developed to fabricate micro components and assemblies at lab scale. 3D Fabrication processes that can accommodate the functional and geometrical requirements to realize complicated structures are becoming feasible through advances in additive manufacturing. This advancement could lead to simpler development mechanisms of novel components and devices exhibiting complex features. For instance, development of microstructure electrodes that can penetrate the epidermis of the skin to collect the bio potential signal may prove very effective than the electrodes that measure signal from the skin's surface. The micro and nanostructures will have to possess extraordinary material and mechanical properties for its dexterity in the applications. A substantial amount of research being pursued on stretchable and flexible devices based on PDMA, textiles, and organic electronics. Despite the numerous advantages these substrates and techniques could solely offer, 3D printing enables a multi-dimensional approach towards finer and complex applications. This review emphasizes the use of 3D printing to fabricate micro and nanostructures for that can be applied for human healthcare.

Characteristics and formation mechanism for stainless steel fiber with periodic micro-fins

NASA Astrophysics Data System (ADS)

Tang, Tao; Wan, Zhenping; Lu, Longsheng; Tang, Yong

2016-05-01

Metal fibers have been widely used in many industrial applications due to their unique advantages. In certain applications, such as catalyst supports or orthopedic implants, a rough surface or tiny outshoots on the surface of metal fibers to increase surface area are needed. However, it has not been concerned about the surface morphologies of metal fiber in the current research of metal fiber manufacturing. In this paper, a special multi-tooth tool composed of a row of triangular tiny teeth is designed. The entire cutting layer of multi-tooth tool bifurcates into several thin cutting layers due to tiny teeth involved in cutting. As a result, several stainless steel fibers with periodic micro-fins are produced simultaneously. Morphology of periodic micro-fins is found to be diverse and can be classified into three categories: unilateral plane, unilateral tapering and bilateral. There are two forming mechanisms for the micro-fins. One is that periodic burrs remained on the free side of cutting layer of a tiny tooth create micro-fins of stainless steel fiber produced by the next neighboring tiny tooth; the other is that the connections between two fibers stuck together come to be micro-fins if the two fibers are finally detached. Influence of cutting conditions on formation of micro-fins is investigated. Experimental results show that cutting depth has no significant effect on micro-fin formation, high cutting speed is conducive to micro-fin formation, and feed should be between 0.12 mm/r and 0.2 mm/r to reliably obtain stainless steel fiber with micro-fins. This research presents a new pattern of stainless steel fiber characterized by periodic micro-fins formed on the edge of fiber and its manufacturing method.

Lighting Equipment (Update to Listing)

DOT National Transportation Integrated Search

1996-05-06

This listing contains equipment and manufacturers certified or deleted since publication of advisory circular 150/5345-53A, Airport lighting equipment certification program, on 5-15-95. The equipment and manufacturers will be added to or deleted from...

Laser figuring for the generation of analog micro-optics and kineform surfaces

NASA Technical Reports Server (NTRS)

Gratrix, Edward J.

1993-01-01

To date, there have been many techniques used to generate micro-optic structures in glass or other materials. Using methods common to the lithographic industry, the manufacturing technique known as 'binary optics,' has demonstrated the use of diffractive optics in a variety of micro-optic applications. It is well established that diffractive structures have limited capability when applied in a design more suited for a refractive element. For applications that demand fast, highly efficient, broadband designs, we have developed a technique which uses laser figuring to generate the refractive micro-optical surface. This paper describes the technique used to fabricate refractive micro-optics. Recent results of micro-optics in CdZnTe focal planes are shown.

Synchrotron X-ray micro-tomography at the Advanced Light Source: Developments in high-temperature in-situ mechanical testing

NASA Astrophysics Data System (ADS)

Barnard, Harold S.; MacDowell, A. A.; Parkinson, D. Y.; Mandal, P.; Czabaj, M.; Gao, Y.; Maillet, E.; Blank, B.; Larson, N. M.; Ritchie, R. O.; Gludovatz, B.; Acevedo, C.; Liu, D.

2017-06-01

At the Advanced Light Source (ALS), Beamline 8.3.2 performs hard X-ray micro-tomography under conditions of high temperature, pressure, mechanical loading, and other realistic conditions using environmental test cells. With scan times of 10s-100s of seconds, the microstructural evolution of materials can be directly observed over multiple time steps spanning prescribed changes in the sample environment. This capability enables in-situ quasi-static mechanical testing of materials. We present an overview of our in-situ mechanical testing capabilities and recent hardware developments that enable flexural testing at high temperature and in combination with acoustic emission analysis.

Fuel-Free Synthetic Micro-/Nanomachines.

PubMed

Xu, Tailin; Gao, Wei; Xu, Li-Ping; Zhang, Xueji; Wang, Shutao

2017-03-01

Inspired by the swimming of natural microorganisms, synthetic micro-/nanomachines, which convert energy into movement, are able to mimic the function of these amazing natural systems and help humanity by completing environmental and biological tasks. While offering autonomous propulsion, conventional micro-/nanomachines usually rely on the decomposition of external chemical fuels (e.g., H 2 O 2 ), which greatly hinders their applications in biologically relevant media. Recent developments have resulted in various micro-/nanomotors that can be powered by biocompatible fuels. Fuel-free synthetic micro-/nanomotors, which can move without external chemical fuels, represent another attractive solution for practical applications owing to their biocompatibility and sustainability. Here, recent developments on fuel-free micro-/nanomotors (powered by various external stimuli such as light, magnetic, electric, or ultrasonic fields) are summarized, ranging from fabrication to propulsion mechanisms. The applications of these fuel-free micro-/nanomotors are also discussed, including nanopatterning, targeted drug/gene delivery, cell manipulation, and precision nanosurgery. With continuous innovation, future autonomous, intelligent and multifunctional fuel-free micro-/nanomachines are expected to have a profound impact upon diverse biomedical applications, providing unlimited opportunities beyond one's imagination. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Investigation of holder pressure and size effects in micro deep drawing of rectangular work pieces driven by piezoelectric actuator.

PubMed

Aminzahed, Iman; Mashhadi, Mahmoud Mosavi; Sereshk, Mohammad Reza Vaziri

2017-02-01

Micro forming is a manufacturing process to fabricate micro parts with high quality and a cost effective manner. Deep drawing could be a favorable method for production of complicated parts in macro and micro sizes. In this paper piezoelectric actuator is used as a novel approach in the field of micro manufacturing. Also, in current work, investigations are conducted with four rectangular punches and blanks with various thicknesses. Blank holder pressure effects on thickness distributions, punch force, and springback are studied. According to the results of this work, increasing of blank holder pressure in scaled deep drawing, in contrast to thickness of drawn part, leads to decrease in the punch forces and springback. Furthermore, it is shown that in micro deep drawing, the effects of holder pressure on mentioned parameters can be ignored. Copyright © 2016 Elsevier B.V. All rights reserved.

Issues and solutions: opportunities for European LED manufacturers

NASA Astrophysics Data System (ADS)

Pearsall, T. P.

2007-09-01

Marketing studies by EPIC show significant revenue opportunities by 2012 for UHB-LEDs in the automotive, LCD backlighting, and architectural lighting sectors. The goal of this workshop on manufacturing issues is to consider five key issues for UHB-LED manufacturing and to propose solutions that will pave the way to full exploitation of the opportunities.

Multi-layered fabrication of large area PDMS flexible optical light guide sheets

NASA Astrophysics Data System (ADS)

Green, Robert; Knopf, George K.; Bordatchev, Evgueni V.

2017-02-01

Large area polydimethylsiloxane (PDMS) flexible optical light guide sheets can be used to create a variety of passive light harvesting and illumination systems for wearable technology, advanced indoor lighting, non-planar solar light collectors, customized signature lighting, and enhanced safety illumination for motorized vehicles. These thin optically transparent micro-patterned polymer sheets can be draped over a flat or arbitrarily curved surface. The light guiding behavior of the optical light guides depends on the geometry and spatial distribution of micro-optical structures, thickness and shape of the flexible sheet, refractive indices of the constituent layers, and the wavelength of the incident light. A scalable fabrication method that combines soft-lithography, closed thin cavity molding, partial curing, and centrifugal casting is described in this paper for building thin large area multi-layered PDMS optical light guide sheets. The proposed fabrication methodology enables the of internal micro-optical structures (MOSs) in the monolithic PDMS light guide by building the optical system layer-by-layer. Each PDMS layer in the optical light guide can have the similar, or a slightly different, indices of refraction that permit total internal reflection within the optical sheet. The individual molded layers may also be defect free or micro-patterned with microlens or reflecting micro-features. In addition, the bond between adjacent layers is ensured because each layer is only partially cured before the next functional layer is added. To illustrate the scalable build-by-layers fabrication method a three-layer mechanically flexible illuminator with an embedded LED strip is constructed and demonstrated.

Light Source

NASA Technical Reports Server (NTRS)

1993-01-01

Research on food growth for long duration spacecraft has resulted in a light source for growing plants indoors known as Qbeam, a solid state light source consisting of a control unit and lamp. The light source, manufactured by Quantum Devices, Inc., is not very hot, although it generates high intensity radiation. When Ron Ignatius, an industrial partner of WCSAR, realized that terrestrial plant research lighting was not energy efficient enough for space use, he and WCSAR began to experiment with light emitting diodes. A line of LED products was developed, and QDI was formed to market the technology. An LED-based cancer treatment device is currently under development.

Ellipsometry-like analysis of polarization state for micro cracks using stress-induced light scattering method

NASA Astrophysics Data System (ADS)

Sakata, Yoshitaro; Terasaki, Nao; Sakai, Kazufumi; Nonaka, Kazuhiro

2016-03-01

Fine polishing techniques, such as chemical mechanical polishing (CMP), are important to glass substrate manufacturing. When these techniques involve mechanical interaction in the form of friction between the abrasive and the substrate surface during polishing, latent flaws may form on the product. Fine polishing induced latent flaws in glass substrates may become obvious during a subsequent cleaning process if the glass surface is eroded away by chemical interaction with a cleaning liquid. Thus, latent flaws reduce product yield. A novel technique (the stress-induced light scattering method; SILSM) which was combined with light scattering method and stress effects was proposed for inspecting surface to detect polishing induced latent flaws. This method is able to distinguish between latent flaws and tiny particles on the surface. In this method, an actuator deforms a sample inducing stress effects around the tip of a latent flaw caused by the deformation, which in turn changes the refractive index of the material around the tip of the latent flaw because of the photoelastic effect. A CCD camera detects this changed refractive index as variations in light-scattering intensity. In this study, the changes in reflection coefficients and polarization states after application of stress to a glass substrate were calculated and evaluated qualitatively using Jones matrix-like ellipsometry. As the results, it was shown that change in the polarization states around the tip of latent flaw were evaluated between before and after applied stress, qualitatively.

Micro- to Macroroughness of Additively Manufactured Titanium Implants in Terms of Coagulation and Contact Activation.

PubMed

Klingvall Ek, Rebecca; Hong, Jaan; Thor, Andreas; Bäckström, Mikael; Rännar, Lars-Erik

This study aimed to evaluate how as-built electron beam melting (EBM) surface properties affect the onset of blood coagulation. The properties of EBM-manufactured implant surfaces for placement have, until now, remained largely unexplored in literature. Implants with conventional designs and custom-made implants have been manufactured using EBM technology and later placed into the human body. Many of the conventional implants used today, such as dental implants, display modified surfaces to optimize bone ingrowth, whereas custom-made implants, by and large, have machined surfaces. However, titanium in itself demonstrates good material properties for the purpose of bone ingrowth. Specimens manufactured using EBM were selected according to their surface roughness and process parameters. EBM-produced specimens, conventional machined titanium surfaces, as well as PVC surfaces for control were evaluated using the slide chamber model. A significant increase in activation was found, in all factors evaluated, between the machined samples and EBM-manufactured samples. The results show that EBM-manufactured implants with as-built surfaces augment the thrombogenic properties. EBM that uses Ti6Al4V powder appears to be a good manufacturing solution for load-bearing implants with bone anchorage. The as-built surfaces can be used "as is" for direct bone contact, although any surface treatment available for conventional implants can be performed on EBM-manufactured implants with a conventional design.

Toughening and healing of composites by CNTs reinforced copolymer nylon micro-particles

NASA Astrophysics Data System (ADS)

Kostopoulos, V.; Kotrotsos, A.; Tsokanas, P.; Tsantzalis, S.

2018-02-01

In this work, nylon micro-particles, both undoped and doped with multiwall carbon nanotubes played the role of the self-healing agent into carbon fibre/epoxy composites (CFRPs). These micro-particles were blended with epoxy matrix and the resulting mixture was used for the composites fabrication. Three types of composites were manufactured; the reference CFRP and the modified CFRPs with undoped and doped nylon micro-particles. After manufacturing, these composites were tested under mode I and II fracture loading conditions and it was shown that the interlaminar fracture toughness characteristics of both nylon modified composites were significantly increased. After first fracture, healing process was activated for the tested nylon modified samples and revealed high fracture toughness characteristics recovery. Morphology examinations supported the results and elucidated the involved toughening and failure mechanisms. Finally, the in-plane mechanical and thermo-mechanical properties of all the composites were characterized for identifying possible knock-down effects due to the nylon modification of composites.

Laser based micro forming and assembly.

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

MacCallum, Danny O'Neill; Wong, Chung-Nin Channy; Knorovsky, Gerald Albert

2006-11-01

It has been shown that thermal energy imparted to a metallic substrate by laser heating induces a transient temperature gradient through the thickness of the sample. In favorable conditions of laser fluence and absorptivity, the resulting inhomogeneous thermal strain leads to a measurable permanent deflection. This project established parameters for laser micro forming of thin materials that are relevant to MESA generation weapon system components and confirmed methods for producing micrometer displacements with repeatable bend direction and magnitude. Precise micro forming vectors were realized through computational finite element analysis (FEA) of laser-induced transient heating that indicated the optimal combination ofmore » laser heat input relative to the material being heated and its thermal mass. Precise laser micro forming was demonstrated in two practical manufacturing operations of importance to the DOE complex: micrometer gap adjustments of precious metal alloy contacts and forming of meso scale cones.« less

Northwest Energy Efficient Manufactured Housing Program: High Performance Manufactured Home Prototyping and Construction Development

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

Hewes, Tom; Peeks, Brady

2013-11-01

The Building America Partnership for Improved Residential Construction, the Bonneville Power Administration (BPA), and Northwest Energy Works (NEW), the current Northwest Energy Efficient Manufactured Housing Program (NEEM) administrator, have been collaborating to conduct research on new specifications that would improve on the energy requirements of a NEEM home. In its role as administrator, NEW administers the technical specs, performs research and engineering analysis, implements ongoing construction quality management procedures, and maintains a central database with home tracking. This project prototyped and assessed the performances of cost-effective high performance building assemblies and mechanical systems that are not commonly deployed in themore » manufacturing setting. The package of measures is able to reduce energy used for space conditioning, water heating and lighting by 50% over typical manufactured homes produced in the northwest.« less

Further Structural Intelligence for Sensors Cluster Technology in Manufacturing

PubMed Central

Mekid, Samir

2006-01-01

With the ever increasing complex sensing and actuating tasks in manufacturing plants, intelligent sensors cluster in hybrid networks becomes a rapidly expanding area. They play a dominant role in many fields from macro and micro scale. Global object control and the ability to self organize into fault-tolerant and scalable systems are expected for high level applications. In this paper, new structural concepts of intelligent sensors and networks with new intelligent agents are presented. Embedding new functionalities to dynamically manage cooperative agents for autonomous machines are interesting key enabling technologies most required in manufacturing for zero defects production.

MEMS Based Micro Aerial Vehicles

NASA Astrophysics Data System (ADS)

Joshi, Niranjan; Köhler, Elof; Enoksson, Peter

2016-10-01

Designing a flapping wing insect robot requires understanding of insect flight mechanisms, wing kinematics and aerodynamic forces. These subsystems are interconnected and their dependence on one another affects the overall performance. Additionally it requires an artificial muscle like actuator and transmission to power the wings. Several kinds of actuators and mechanisms are candidates for this application with their own strengths and weaknesses. This article provides an overview of the insect scaled flight mechanism along with discussion of various methods to achieve the Micro Aerial Vehicle (MAV) flight. Ongoing projects in Chalmers is aimed at developing a low cost and low manufacturing time MAV. The MAV design considerations and design specifications are mentioned. The wings are manufactured using 3D printed carbon fiber and are under experimental study.

All solution-processed micro-structured flexible electrodes for low-cost light-emitting pressure sensors fabrication.

PubMed

Shimotsu, Rie; Takumi, Takahiro; Vohra, Varun

2017-07-31

Recent studies have demonstrated the advantage of developing pressure-sensitive devices with light-emitting properties for direct visualization of pressure distribution, potential application to next generation touch panels and human-machine interfaces. To ensure that this technology is available to everyone, its production cost should be kept as low as possible. Here, simple device concepts, namely, pressure sensitive flexible hybrid electrodes and OLED architecture, are used to produce low-cost resistive or light-emitting pressure sensors. Additionally, integrating solution-processed self-assembled micro-structures into the flexible hybrid electrodes composed of an elastomer and conductive materials results in enhanced device performances either in terms of pressure or spatial distribution sensitivity. For instance, based on the pressure applied, the measured values for the resistances of pressure sensors range from a few MΩ down to 500 Ω. On the other hand, unlike their evaporated equivalents, the combination of solution-processed flexible electrodes with an inverted OLED architectures display bright green emission when a pressure over 200 kPa is applied. At a bias of 3 V, their luminance can be tuned by applying a higher pressure of 500 kPa. Consequently, features such as fingernails and fingertips can be clearly distinguished from one another in these long-lasting low-cost devices.

Structural Color for Additive Manufacturing: 3D-Printed Photonic Crystals from Block Copolymers.

PubMed

Boyle, Bret M; French, Tracy A; Pearson, Ryan M; McCarthy, Blaine G; Miyake, Garret M

2017-03-28

The incorporation of structural color into 3D printed parts is reported, presenting an alternative to the need for pigments or dyes for colored parts produced through additive manufacturing. Thermoplastic build materials composed of dendritic block copolymers were designed, synthesized, and used to additively manufacture plastic parts exhibiting structural color. The reflection properties of the photonic crystals arise from the periodic nanostructure formed through block copolymer self-assembly during polymer processing. The wavelength of reflected light could be tuned across the visible spectrum by synthetically controlling the block copolymer molecular weight and manufacture parts that reflected violet, green, or orange light with the capacity to serve as selective optical filters and light guides.

Additive Manufacturing in Production: A Study Case Applying Technical Requirements

NASA Astrophysics Data System (ADS)

Ituarte, Iñigo Flores; Coatanea, Eric; Salmi, Mika; Tuomi, Jukka; Partanen, Jouni

Additive manufacturing (AM) is expanding the manufacturing capabilities. However, quality of AM produced parts is dependent on a number of machine, geometry and process parameters. The variability of these parameters affects the manufacturing drastically and therefore standardized processes and harmonized methodologies need to be developed to characterize the technology for end use applications and enable the technology for manufacturing. This research proposes a composite methodology integrating Taguchi Design of Experiments, multi-objective optimization and statistical process control, to optimize the manufacturing process and fulfil multiple requirements imposed to an arbitrary geometry. The proposed methodology aims to characterize AM technology depending upon manufacturing process variables as well as to perform a comparative assessment of three AM technologies (Selective Laser Sintering, Laser Stereolithography and Polyjet). Results indicate that only one machine, laser-based Stereolithography, was feasible to fulfil simultaneously macro and micro level geometrical requirements but mechanical properties were not at required level. Future research will study a single AM system at the time to characterize AM machine technical capabilities and stimulate pre-normative initiatives of the technology for end use applications.

Micro electro mechanical system optical switching

DOEpatents

Thorson, Kevin J; Stevens, Rick C; Kryzak, Charles J; Leininger, Brian S; Kornrumpf, William P; Forman, Glenn A; Iannotti, Joseph A; Spahn, Olga B; Cowan, William D; Dagel, Daryl J

2013-12-17

The present disclosure includes apparatus, system, and method embodiments that provide micro electo mechanical system optical switching and methods of manufacturing switches. For example, one optical switch embodiment includes at least one micro electro mechanical system type pivot mirror structure disposed along a path of an optical signal, the structure having a mirror and an actuator, and the mirror having a pivot axis along a first edge and having a second edge rotatable with respect to the pivot axis, the mirror being capable of and arranged to be actuated to pivot betweeen a position parallel to a plane of an optical signal and a position substantially normal to the plane of the optical signal.

Hybrid optical fiber add-drop filter based on wavelength dependent light coupling between micro/nano fiber ring and side-polished fiber

PubMed Central

Yu, Jianhui; Jin, Shaoshen; Wei, Qingsong; Zang, Zhigang; Lu, Huihui; He, Xiaoli; Luo, Yunhan; Tang, Jieyuan; Zhang, Jun; Chen, Zhe

2015-01-01

In this paper, we report our experimental study on directly coupling a micro/nano fiber (MNOF) ring with a side-polished fiber(SPF). As a result of the study, the behavior of an add-drop filter was observed. The demonstrated add-drop filter explored the wavelength dependence of light coupling between a MNOF ring and a SPF. The characteristics of the filter and its performance dependence on the MNOF ring diameter were investigated experimentally. The investigation resulted in an empirically obtained ring diameter that showed relatively good filter performance. Since light coupling between a (MNOF) and a conventional single mode fiber has remained a challenge in the photonic integration community, the present study may provide an alternative way to couple light between a MNOF device and a conventional single mode fiber based device or system. The hybridization approach that uses a SPF as a platform to integrate a MNOF device may enable the realization of other all-fiber optical hybrid devices. PMID:25578467

Hybrid optical fiber add-drop filter based on wavelength dependent light coupling between micro/nano fiber ring and side-polished fiber

NASA Astrophysics Data System (ADS)

Yu, Jianhui; Jin, Shaoshen; Wei, Qingsong; Zang, Zhigang; Lu, Huihui; He, Xiaoli; Luo, Yunhan; Tang, Jieyuan; Zhang, Jun; Chen, Zhe

2015-01-01

In this paper, we report our experimental study on directly coupling a micro/nano fiber (MNOF) ring with a side-polished fiber(SPF). As a result of the study, the behavior of an add-drop filter was observed. The demonstrated add-drop filter explored the wavelength dependence of light coupling between a MNOF ring and a SPF. The characteristics of the filter and its performance dependence on the MNOF ring diameter were investigated experimentally. The investigation resulted in an empirically obtained ring diameter that showed relatively good filter performance. Since light coupling between a (MNOF) and a conventional single mode fiber has remained a challenge in the photonic integration community, the present study may provide an alternative way to couple light between a MNOF device and a conventional single mode fiber based device or system. The hybridization approach that uses a SPF as a platform to integrate a MNOF device may enable the realization of other all-fiber optical hybrid devices.

Hybrid optical fiber add-drop filter based on wavelength dependent light coupling between micro/nano fiber ring and side-polished fiber.

PubMed

Yu, Jianhui; Jin, Shaoshen; Wei, Qingsong; Zang, Zhigang; Lu, Huihui; He, Xiaoli; Luo, Yunhan; Tang, Jieyuan; Zhang, Jun; Chen, Zhe

2015-01-12

In this paper, we report our experimental study on directly coupling a micro/nano fiber (MNOF) ring with a side-polished fiber(SPF). As a result of the study, the behavior of an add-drop filter was observed. The demonstrated add-drop filter explored the wavelength dependence of light coupling between a MNOF ring and a SPF. The characteristics of the filter and its performance dependence on the MNOF ring diameter were investigated experimentally. The investigation resulted in an empirically obtained ring diameter that showed relatively good filter performance. Since light coupling between a (MNOF) and a conventional single mode fiber has remained a challenge in the photonic integration community, the present study may provide an alternative way to couple light between a MNOF device and a conventional single mode fiber based device or system. The hybridization approach that uses a SPF as a platform to integrate a MNOF device may enable the realization of other all-fiber optical hybrid devices.

Design, development and use of the spectrometer for investigating coherent THz radiation produced by micro-bunching instabilities at Diamond Light Source

NASA Astrophysics Data System (ADS)

Finn, Aiveen; Karataev, Pavel; Rehm, Guenther

2016-07-01

Schottky barrier diodes (SBDs) are known for their low noise, ultra-fast response and excellent sensitivity. They are often implemented as detectors in the millimetre wavelength regime. Micro-bunch instabilities (MBI) have been detected at many light sources around the world including the Diamond Light Source, UK. These MBI can result in bursts of coherent synchrotron radiation (CSR) with millimetre wavelengths. More research needs to be carried out with regards to the dynamics of MBI in order to confirm the simulations and to eventually harness the power of the CSR bursts. A single shot spectrometer has been designed and is under operation at the Diamond Light Source (DLS). It is composed of eight SBDs ranging from 33-1000 GHz. Unlike previous measurements carried out, each of the SBDs has been individually characterised thus making the results obtained comparable to simulations. In this paper, we present the assessment of each SBD in the spectrometer and the first results of the spectrometer's use in the beam.

Micro axial tomography: A miniaturized, versatile stage device to overcome resolution anisotropy in fluorescence light microscopy

NASA Astrophysics Data System (ADS)

Staier, Florian; Eipel, Heinz; Matula, Petr; Evsikov, Alexei V.; Kozubek, Michal; Cremer, Christoph; Hausmann, Michael

2011-09-01

With the development of novel fluorescence techniques, high resolution light microscopy has become a challenging technique for investigations of the three-dimensional (3D) micro-cosmos in cells and sub-cellular components. So far, all fluorescence microscopes applied for 3D imaging in biosciences show a spatially anisotropic point spread function resulting in an anisotropic optical resolution or point localization precision. To overcome this shortcoming, micro axial tomography was suggested which allows object tilting on the microscopic stage and leads to an improvement in localization precision and spatial resolution. Here, we present a miniaturized device which can be implemented in a motor driven microscope stage. The footprint of this device corresponds to a standard microscope slide. A special glass fiber can manually be adjusted in the object space of the microscope lens. A stepwise fiber rotation can be controlled by a miniaturized stepping motor incorporated into the device. By means of a special mounting device, test particles were fixed onto glass fibers, optically localized with high precision, and automatically rotated to obtain views from different perspective angles under which distances of corresponding pairs of objects were determined. From these angle dependent distance values, the real 3D distance was calculated with a precision in the ten nanometer range (corresponding here to an optical resolution of 10-30 nm) using standard microscopic equipment. As a proof of concept, the spindle apparatus of a mature mouse oocyte was imaged during metaphase II meiotic arrest under different perspectives. Only very few images registered under different rotation angles are sufficient for full 3D reconstruction. The results indicate the principal advantage of the micro axial tomography approach for many microscopic setups therein and also those of improved resolutions as obtained by high precision localization determination.

Investigation on Clarified Fruit Juice Composition by Using Visible Light Micro-Raman Spectroscopy.

PubMed

Camerlingo, Carlo; Zenone, Flora; Delfino, Ines; Diano, Nadia; Mita, Damiano Gustavo; Lepore, Maria

2007-10-03

Liquid samples of clarified apple and apricot juices at different productionstages were investigated using visible light micro-Raman spectroscopy in order to assessits potential in monitoring fruit juice production. As is well-known, pectin plays a strategicrole in the production of clarified juice and the possibility of using Raman for its detectionduring production was therefore evaluated. The data analysis has enabled the clearidentification of pectin. In particular, Raman spectra of apple juice samples from washedand crushed fruits revealed a peak at 845 cm -1 (typical of pectin) which disappears in theRaman spectra of depectinised samples. The fructose content was also revealed by thepresence of four peaks at 823 cm -1 , 872 cm -1 , 918 cm -1 and 975 cm -1 . In the case of apricotjuice, several Raman fingerprints of β-carotene at 1008, 1159 and 1520 cm -1 were alsohighlighted. Present results resulted interesting for the exclusive use of optical methods forthe quantitative determination of the above-mentioned substances in place of thebiochemical assays generally used for this purpose, which are time consuming and requiredifferent chemical reagents for each of them.

Opportunities and challenges for 3D printing of solid-state lighting systems

NASA Astrophysics Data System (ADS)

Narendran, Nadarajah; Perera, Indika U.; Mou, Xi; Thotagamuwa, Dinusha R.

2017-09-01

Low energy use and reduced maintenance have made the LED, a solid-state light (SSL) source, the preferred technology for many lighting applications. With the explosion of products in the marketplace and subsequent price erosion, manufacturers are looking for lower cost materials and manufacturing methods. 3-D printing, also known as additive manufacturing, could be a potential solution. Recently, manufacturers in the automotive, aerospace, and medical industries have embraced 3-D printing for manufacturing parts and systems. This could pave the way for the lighting industry to produce lower cost, custom lighting systems that are 3-D printed on-site to achieve on-time and on-demand manufacturing. One unique aspect of LED fixture manufacturing is that it requires thermo-mechanical, electrical, and optical components. The goal of our investigation was to understand if current 3-D printing technologies and materials can be used to manufacture functional thermo-mechanical, electrical, and optical components for SSL fixtures. We printed heat sink components and electrical traces using an FFF-type 3-D printer with different filaments. The results showed that the printed heat sinks achieved higher thermal conductivity values compared to components made with plastic materials. For electrical traces, graphene-infused PLA showed low resistivity but it is much higher than bulk copper resistivity. For optics, SLA-printed optical components showed that print resolution, print orientation, and postprocessing affect light transmission and light scatter properties. Overall, 3-D printing offers an opportunity for mass customization of SSL fixtures and changing architectural lighting practice, but several challenges in terms of process and materials still have to be overcome.

Historical Financial Data - Domestic Automobile Manufacturers

DOT National Transportation Integrated Search

1979-01-01

A historical financial data base was developed for the four major U.S. automobile manufacturers, focusing on the specific operations associated with production and marketing of automobiles and light trucks. The years subject to analysis were 1967-197...

Multilayer white lighting polymer light-emitting diodes

NASA Astrophysics Data System (ADS)

Gong, Xiong; Wang, Shu; Heeger, Alan J.

2006-08-01

Organic and polymer light-emitting diodes (OLEDs/PLEDs) that emit white light are of interest and potential importance for use in active matrix displays (with color filters) and because they might eventually be used for solid-state lighting. In such applications, large-area devices and low-cost of manufacturing will be major issues. We demonstrated that high performance multilayer white emitting PLEDs can be fabricated by using a blend of luminescent semiconducting polymers and organometallic complexes as the emission layer, and water-soluble (or ethanol-soluble) polymers/small molecules (for example, PVK-SO 3Li) as the hole injection/transport layer (HIL/HTL) and water-soluble (or ethanol-soluble) polymers/small molecules (for example, t-Bu-PBD-SO 3Na) as the electron injection/transport layer (EIL/HTL). Each layer is spin-cast sequentially from solutions. Illumination quality light is obtained with stable Commission Internationale d'Eclairage coordinates, stable color temperatures, and stable high color rendering indices, all close to those of "pure" white. The multilayer white-emitting PLEDs exhibit luminous efficiency of 21 cd/A, power efficiency of 6 lm/W at a current density of 23 mA/cm2 with luminance of 5.5 x 10 4 cd/m2 at 16 V. By using water-soluble (ethanol-soluble) polymers/small molecules as HIL/HTL and polymers/small molecules as EIL/ETL, the interfacial mixing problem is solved (the emissive polymer layer is soluble in organic solvents, but not in water/ ethanol). As a result, this device architecture and process technology can potentially be used for printing large-area multiplayer light sources and for other applications in "plastic" electronics. More important, the promise of producing large areas of high quality white light with low-cost manufacturing technology makes the white multilayer white-emitting PLEDs attractive for the development of solid state light sources.

Large Scale Composite Manufacturing for Heavy Lift Launch Vehicles

NASA Technical Reports Server (NTRS)

Stavana, Jacob; Cohen, Leslie J.; Houseal, Keth; Pelham, Larry; Lort, Richard; Zimmerman, Thomas; Sutter, James; Western, Mike; Harper, Robert; Stuart, Michael

2012-01-01

Risk reduction for the large scale composite manufacturing is an important goal to produce light weight components for heavy lift launch vehicles. NASA and an industry team successfully employed a building block approach using low-cost Automated Tape Layup (ATL) of autoclave and Out-of-Autoclave (OoA) prepregs. Several large, curved sandwich panels were fabricated at HITCO Carbon Composites. The aluminum honeycomb core sandwich panels are segments of a 1/16th arc from a 10 meter cylindrical barrel. Lessons learned highlight the manufacturing challenges required to produce light weight composite structures such as fairings for heavy lift launch vehicles.

INVESTIGATION OF TITANIUM BONDED GRAPHITE FOAM COMPOSITES FOR MICRO ELECTRONIC MECHANICAL SYSTEMS (MEMS) APPLICATIONS

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

Menchhofer, Paul A.

PiMEMS Inc. (Santa Barbara, CA) in collaboration with ORNL investigated the use of Titanium Bonded Graphite Foam Composites (TBGC) for thermal mitigation in Micro Electronic Mechanical Systems (MEMS) applications. Also considered were potentially new additive manufacturing routes to producing novel high surface area micro features and diverse shaped heat transfer components for numerous lightweight MEMs applications.

Northwest Energy Efficient Manufactured Housing Program: High Performance Manufactured Home Prototyping and Construction Development

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

Hewes, Tom; Peeks, Brady

2013-11-01

The Building America Partnership for Improved Residential Construction, the Bonneville Power Administration (BPA), and Northwest Energy Works (NEW), the current Northwest Energy Efficient Manufactured Housing Program (NEEM) administrator, have been collaborating to conduct research on new specifications that would improve on the energy requirements of a NEEM home. In its role as administrator, NEW administers the technical specs, performs research and engineering analysis, implements ongoing construction quality management procedures, and maintains a central database with home tracking. This project prototyped and assessed the performances of cost-effective high performance building assemblies and mechanical systems that are not commonly deployed in themore » manufacturing setting. The package of measures is able to reduce energy used for space conditioning, water heating and lighting by 50 percent over typical manufactured homes produced in the northwest.« less

A demonstration of particle duality of light

NASA Astrophysics Data System (ADS)

Jiang, Haili; Liu, Zhihai; Sun, Qiuhua; Zhao, Yancheng

2017-08-01

The need of understanding and teaching about wave-particle duality if light with gets more and more apparent in the background of the attention of modern physics. As early as the beginning of twentieth Century, Einstein dared to "deny" the development of a very perfect light electromagnetic theory, so that the quantum of light can be developed. In 1924, De Broglie put forward wave-particle duality if light to other micro particles and the concept of matter wave, pointed out that all micro particle has wave-particle duality. This is a very abstract concept for students, most college physics teaching all lack of demonstration about particle duality of light. The present article aims to contribute to demonstrate the wave-particle duality of light at the same time using a simple way based on fiber optical tweezers. It is hoped that useful lesson can be absorbed so that students can deepen the understanding of the particle and wave properties of light. To complement the demonstration experiment for this attribute light has momentum.

Calibration and analysis of a multimodal micro-CT and structured light imaging system for the evaluation of excised breast tissue

NASA Astrophysics Data System (ADS)

McClatchy, David M., III; Rizzo, Elizabeth J.; Meganck, Jeff; Kempner, Josh; Vicory, Jared; Wells, Wendy A.; Paulsen, Keith D.; Pogue, Brian W.

2017-12-01

A multimodal micro-computed tomography (CT) and multi-spectral structured light imaging (SLI) system is introduced and systematically analyzed to test its feasibility to aid in margin delineation during breast conserving surgery (BCS). Phantom analysis of the micro-CT yielded a signal-to-noise ratio of 34, a contrast of 1.64, and a minimum detectable resolution of 240 μm for a 1.2 min scan. The SLI system, spanning wavelengths 490 nm to 800 nm and spatial frequencies up to 1.37 mm-1 , was evaluated with aqueous tissue simulating phantoms having variations in particle size distribution, scatter density, and blood volume fraction. The reduced scattering coefficient, μs\\prime and phase function parameter, γ, were accurately recovered over all wavelengths independent of blood volume fractions from 0% to 4%, assuming a flat sample geometry perpendicular to the imaging plane. The resolution of the optical system was tested with a step phantom, from which the modulation transfer function was calculated yielding a maximum resolution of 3.78 cycles per mm. The three dimensional spatial co-registration between the CT and optical imaging space was tested and shown to be accurate within 0.7 mm. A freshly resected breast specimen, with lobular carcinoma, fibrocystic disease, and adipose, was imaged with the system. The micro-CT provided visualization of the tumor mass and its spiculations, and SLI yielded superficial quantification of light scattering parameters for the malignant and benign tissue types. These results appear to be the first demonstration of SLI combined with standard medical tomography for imaging excised tumor specimens. While further investigations are needed to determine and test the spectral, spatial, and CT features required to classify tissue, this study demonstrates the ability of multimodal CT/SLI to quantify, visualize, and spatially navigate breast tumor specimens, which could potentially aid in the assessment of tumor margin status during

Ceramic components manufacturing by selective laser sintering

NASA Astrophysics Data System (ADS)

Bertrand, Ph.; Bayle, F.; Combe, C.; Goeuriot, P.; Smurov, I.

2007-12-01

In the present paper, technology of selective laser sintering/melting is applied to manufacture net shaped objects from pure yttria-zirconia powders. Experiments are carried out on Phenix Systems PM100 machine with 50 W fibre laser. Powder is spread by a roller over the surface of 100 mm diameter alumina cylinder. Design of experiments is applied to identify influent process parameters (powder characteristics, powder layering and laser manufacturing strategy) to obtain high-quality ceramic components (density and micro-structure). The influence of the yttria-zirconia particle size and morphology onto powder layering process is analysed. The influence of the powder layer thickness on laser sintering/melting is studied for different laser beam velocity V ( V = 1250-2000 mm/s), defocalisation (-6 to 12 mm), distance between two neighbour melted lines (so-called "vectors") (20-40 μm), vector length and temperature in the furnace. The powder bed density before laser sintering/melting also has significant influence on the manufactured samples density. Different manufacturing strategies are applied and compared: (a) different laser beam scanning paths to fill the sliced surfaces of the manufactured object, (b) variation of vector length (c) different strategies of powder layering, (d) temperature in the furnace and (e) post heat treatment in conventional furnace. Performance and limitations of different strategies are analysed applying the following criteria: geometrical accuracy of the manufactured samples, porosity. The process stability is proved by fabrication of 1 cm 3 volume cube.

Thermoeconomical Productivity Analysis in Manufacturing Sector in Indonesia

NASA Astrophysics Data System (ADS)

Liana Aji, Widya; Purqon, Acep

2017-07-01

Negative temperature is a phenomenon interesting to study. In negative temperature regime, Boltzmann distribution is inverted where many particles occupy the higher energy states than the lower one. Iyetomi proposed a negative temperature case in Japan and applied it to the labor productivity distribution where the particle and energy state are replaced by worker and labor productivity, respectively. In this paper, we investigate the negative temperature concept to the labor productivity distribution in manufacturing sector in Indonesia which is divided by three industry groups according to BPS (Center of Statistical Agency of Indonesia), i. e. large and medium industries, small industry, and micro industry. For all industry groups, food industry possesses maximum productivity. The results represent that the negative temperature of large and medium industries is around ten times lower than negative temperature of micro industry indicating large and medium industries is lack demand of worker, while the negative temperature of small industry is among the temperature negative of large and medium industries and micro industry.

The collection of MicroED data for macromolecular crystallography.

PubMed

Shi, Dan; Nannenga, Brent L; de la Cruz, M Jason; Liu, Jinyang; Sawtelle, Steven; Calero, Guillermo; Reyes, Francis E; Hattne, Johan; Gonen, Tamir

2016-05-01

The formation of large, well-ordered crystals for crystallographic experiments remains a crucial bottleneck to the structural understanding of many important biological systems. To help alleviate this problem in crystallography, we have developed the MicroED method for the collection of electron diffraction data from 3D microcrystals and nanocrystals of radiation-sensitive biological material. In this approach, liquid solutions containing protein microcrystals are deposited on carbon-coated electron microscopy grids and are vitrified by plunging them into liquid ethane. MicroED data are collected for each selected crystal using cryo-electron microscopy, in which the crystal is diffracted using very few electrons as the stage is continuously rotated. This protocol gives advice on how to identify microcrystals by light microscopy or by negative-stain electron microscopy in samples obtained from standard protein crystallization experiments. The protocol also includes information about custom-designed equipment for controlling crystal rotation and software for recording experimental parameters in diffraction image metadata. Identifying microcrystals, preparing samples and setting up the microscope for diffraction data collection take approximately half an hour for each step. Screening microcrystals for quality diffraction takes roughly an hour, and the collection of a single data set is ∼10 min in duration. Complete data sets and resulting high-resolution structures can be obtained from a single crystal or by merging data from multiple crystals.

Managing the Manpower Aspects of Applying Micro-Electronics Technology.

ERIC Educational Resources Information Center

Thornton, P.; Routledge, C.

1980-01-01

Outlines major effects that the application of micro-electronics devices in products/processes and in office systems will have on future manpower and skill requirements in manufacturing organizations. Identifies the type of problems these changes will pose for manpower managers. Provides general guidelines for the successful management of these…

40 CFR 86.1836-01 - Manufacturer-supplied production vehicles for testing.

Code of Federal Regulations, 2010 CFR

2010-07-01

... ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles § 86.1836-01 Manufacturer...

Materials Characterization of Additively Manufactured Components for Rocket Propulsion

NASA Technical Reports Server (NTRS)

Carter, Robert; Draper, Susan; Locci, Ivan; Lerch, Bradley; Ellis, David; Senick, Paul; Meyer, Michael; Free, James; Cooper, Ken; Jones, Zachary

2015-01-01

To advance Additive Manufacturing (AM) technologies for production of rocket propulsion components the NASA Glenn Research Center (GRC) is applying state of the art characterization techniques to interrogate microstructure and mechanical properties of AM materials and components at various steps in their processing. The materials being investigated for upper stage rocket engines include titanium, copper, and nickel alloys. Additive manufacturing processes include laser powder bed, electron beam powder bed, and electron beam wire fed processes. Various post build thermal treatments, including Hot Isostatic Pressure (HIP), have been studied to understand their influence on microstructure, mechanical properties, and build density. Micro-computed tomography, electron microscopy, and mechanical testing in relevant temperature environments has been performed to develop relationships between build quality, microstructure, and mechanical performance at temperature. A summary of GRC's Additive Manufacturing roles and experimental findings will be presented.

Material Characterization of Additively Manufactured Components for Rocket Propulsion

NASA Technical Reports Server (NTRS)

Carter, Robert; Draper, Susan; Locci, Ivan; Lerch, Bradley; Ellis, David; Senick, Paul; Meyer, Michael; Free, James; Cooper, Ken; Jones, Zachary

2015-01-01

To advance Additive Manufacturing (AM) technologies for production of rocket propulsion components the NASA Glenn Research Center (GRC) is applying state of the art characterization techniques to interrogate microstructure and mechanical properties of AM materials and components at various steps in their processing. The materials being investigated for upper stage rocket engines include titanium, copper, and nickel alloys. Additive manufacturing processes include laser powder bed, electron beam powder bed, and electron beam wire fed processes. Various post build thermal treatments, including Hot Isostatic Pressure (HIP), have been studied to understand their influence on microstructure, mechanical properties, and build density. Micro-computed tomography, electron microscopy, and mechanical testing in relevant temperature environments has been performed to develop relationships between build quality, microstructure, and mechanical performance at temperature. A summary of GRCs Additive Manufacturing roles and experimental findings will be presented.

ZnO-based microrockets with light-enhanced propulsion.

PubMed

Dong, Renfeng; Wang, Chun; Wang, Qinglong; Pei, Allen; She, Xueling; Zhang, Yuxian; Cai, Yuepeng

2017-10-12

Improving the propulsion of artificial micro-nanomotors represents an exciting nanotechnology challenge, especially considering their cargo delivery ability and fuel efficiency. In light of the excellent photocatalytic performance of zinc oxide (ZnO) and chemical catalytic properties of platinum (Pt), ZnO-Pt microrockets with light-enhanced propulsion have been developed by atomic layer deposition (ALD) technology. The velocity of such microrockets is dramatically doubled upon irradiation by 77 mW cm -2 ultraviolet (UV) light in 10% H 2 O 2 and is almost 3 times higher than the classic poly(3,4-ethylenedioxythiophene)-Pt microrockets (PEDOT-Pt microrockets) even in 6% H 2 O 2 under the same UV light. In addition, such micromotors not only retain the standard approach to improve propulsion by varying the fuel concentration, but also demonstrate a simple way to enhance the movement velocity by adjusting the UV light intensity. High reversibility and controllable "weak/strong" propulsion can be easily achieved by switching the UV irradiation on or off. Finally, light-enhanced propulsion has been investigated by electrochemical measurements which further confirm the enhanced photocatalytic properties of ZnO and Pt. The successful demonstration of ZnO-based microrockets with excellent light-enhanced propulsion is significant for developing highly efficient synthetic micro-nanomotors which have strong delivery ability and economic fuel requirements for future practical applications in the micro-nanoscale world.

Life of LED-Based White Light Sources

NASA Astrophysics Data System (ADS)

Narendran, Nadarajah; Gu, Yimin

2005-09-01

Even though light-emitting diodes (LEDs) may have a very long life, poorly designed LED lighting systems can experience a short life. Because heat at the p-n-junction is one of the main factors that affect the life of the LED, by knowing the relationship between life and heat, LED system manufacturers can design and build long-lasting systems. In this study, several white LEDs from the same manufacturer were subjected to life tests at different ambient temperatures. The exponential decay of light output as a function of time provided a convenient method to rapidly estimate life by data extrapolation. The life of these LEDs decreases in an exponential manner with increasing temperature. In a second experiment,several high-power white LEDs from different manufacturers were life-tested under similar conditions. Results show that the different products have significantly different life values.

Femtosecond laser three-dimensional micro- and nanofabrication

NASA Astrophysics Data System (ADS)

Sugioka, Koji; Cheng, Ya

2014-12-01

The rapid development of the femtosecond laser has revolutionized materials processing due to its unique characteristics of ultrashort pulse width and extremely high peak intensity. The short pulse width suppresses the formation of a heat-affected zone, which is vital for ultrahigh precision fabrication, whereas the high peak intensity allows nonlinear interactions such as multiphoton absorption and tunneling ionization to be induced in transparent materials, which provides versatility in terms of the materials that can be processed. More interestingly, irradiation with tightly focused femtosecond laser pulses inside transparent materials makes three-dimensional (3D) micro- and nanofabrication available due to efficient confinement of the nonlinear interactions within the focal volume. Additive manufacturing (stereolithography) based on multiphoton absorption (two-photon polymerization) enables the fabrication of 3D polymer micro- and nanostructures for photonic devices, micro- and nanomachines, and microfluidic devices, and has applications for biomedical and tissue engineering. Subtractive manufacturing based on internal modification and fabrication can realize the direct fabrication of 3D microfluidics, micromechanics, microelectronics, and photonic microcomponents in glass. These microcomponents can be easily integrated in a single glass microchip by a simple procedure using a femtosecond laser to realize more functional microdevices, such as optofluidics and integrated photonic microdevices. The highly localized multiphoton absorption of a tightly focused femtosecond laser in glass can also induce strong absorption only at the interface of two closely stacked glass substrates. Consequently, glass bonding can be performed based on fusion welding with femtosecond laser irradiation, which provides the potential for applications in electronics, optics, microelectromechanical systems, medical devices, microfluidic devices, and small satellites. This review paper

Femtosecond laser three-dimensional micro- and nanofabrication

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

Sugioka, Koji, E-mail: ksugioka@riken.jp; Cheng, Ya, E-mail: ya.cheng@siom.ac.cn

2014-12-15

The rapid development of the femtosecond laser has revolutionized materials processing due to its unique characteristics of ultrashort pulse width and extremely high peak intensity. The short pulse width suppresses the formation of a heat-affected zone, which is vital for ultrahigh precision fabrication, whereas the high peak intensity allows nonlinear interactions such as multiphoton absorption and tunneling ionization to be induced in transparent materials, which provides versatility in terms of the materials that can be processed. More interestingly, irradiation with tightly focused femtosecond laser pulses inside transparent materials makes three-dimensional (3D) micro- and nanofabrication available due to efficient confinement ofmore » the nonlinear interactions within the focal volume. Additive manufacturing (stereolithography) based on multiphoton absorption (two-photon polymerization) enables the fabrication of 3D polymer micro- and nanostructures for photonic devices, micro- and nanomachines, and microfluidic devices, and has applications for biomedical and tissue engineering. Subtractive manufacturing based on internal modification and fabrication can realize the direct fabrication of 3D microfluidics, micromechanics, microelectronics, and photonic microcomponents in glass. These microcomponents can be easily integrated in a single glass microchip by a simple procedure using a femtosecond laser to realize more functional microdevices, such as optofluidics and integrated photonic microdevices. The highly localized multiphoton absorption of a tightly focused femtosecond laser in glass can also induce strong absorption only at the interface of two closely stacked glass substrates. Consequently, glass bonding can be performed based on fusion welding with femtosecond laser irradiation, which provides the potential for applications in electronics, optics, microelectromechanical systems, medical devices, microfluidic devices, and small satellites. This review

Development of micro-mirror slicer integral field unit for space-borne solar spectrographs

NASA Astrophysics Data System (ADS)

Suematsu, Yoshinori; Saito, Kosuke; Koyama, Masatsugu; Enokida, Yukiya; Okura, Yukinobu; Nakayasu, Tomoyasu; Sukegawa, Takashi

2017-12-01

We present an innovative optical design for image slicer integral field unit (IFU) and a manufacturing method that overcomes optical limitations of metallic mirrors. Our IFU consists of a micro-mirror slicer of 45 arrayed, highly narrow, flat metallic mirrors and a pseudo-pupil-mirror array of off-axis conic aspheres forming three pseudo slits of re-arranged slicer images. A prototype IFU demonstrates that the final optical quality is sufficiently high for a visible light spectrograph. Each slicer micro-mirror is 1.58 mm long and 30 μm wide with surface roughness ≤1 nm rms, and edge sharpness ≤ 0.1 μm, etc. This IFU is small size and can be implemented in a multi-slit spectrograph without any moving mechanism and fore optics, in which one slit is real and the others are pseudo slits from the IFU. The IFU mirrors were deposited by a space-qualified, protected silver coating for high reflectivity in visible and near IR wavelength regions. These properties are well suitable for space-borne spectrograph such as the future Japanese solar space mission SOLAR-C. We present the optical design, performance of prototype IFU, and space qualification tests of the silver coating.

Modeling and Reconstruction of Micro-structured 3D Chitosan/Gelatin Porous Scaffolds Using Micro-CT

NASA Astrophysics Data System (ADS)

Gong, Haibo; Li, Dichen; He, Jiankang; Liu, Yaxiong; Lian, Qin; Zhao, Jinna

2008-09-01

Three dimensional (3D) channel networks are the key to promise the uniform distribution of nutrients inside 3D hepatic tissue engineering scaffolds and prompt elimination of metabolic products out of the scaffolds. 3D chitosan/gelatin porous scaffolds with predefined internal channels were fabricated and a combination of light microscope, laser confocal microscopy and micro-CT were employed to characterize the structure of porous scaffolds. In order to evaluate the flow field distribution inside the micro-structured 3D scaffolds, a computer reconstructing method based on Micro-CT was proposed. According to this evaluating method, a contrast between 3D porous scaffolds with and without predefined internal channels was also performed to assess scaffolds' fluid characters. Results showed that the internal channel of the 3D scaffolds formed the 3D fluid channel network; the uniformity of flow field distribution of the scaffolds fabricated in this paper was better than the simple porous scaffold without micro-fluid channels.

Technology Solutions for New Manufactured Homes: Idaho, Oregon, and Washington Manufactured Home Builders (Fact Sheet)

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

None, None

2013-11-01

The Building America Partnership for Improved Residential Construction, the Bonneville Power Administration (BPA), and Northwest Energy Works (NEW), the current Northwest Energy Efficient Manufactured Housing Program (NEEM) administrator, have been collaborating to conduct research on new specifications that would improve on the energy requirements of a NEEM home. In its role as administrator, NEW administers the technical specs, performs research and engineering analysis, implements ongoing construction quality management procedures, and maintains a central database with home tracking. This project prototyped and assessed the performances of cost-effective high performance building assemblies and mechanical systems that are not commonly deployed in themore » manufacturing setting. The package of measures is able to reduce energy used for space conditioning, water heating and lighting by 50 percent over typical manufactured homes produced in the northwest.« less

Micro guidance and control synthesis: New components, architectures, and capabilities

NASA Technical Reports Server (NTRS)

Mettler, Edward; Hadaegh, Fred Y.

1993-01-01

New GN&C (guidance, navigation and control) system capabilities are shown to arise from component innovations that involve the synergistic use of microminiature sensors and actuators, microelectronics, and fiber optics. Micro-GN&C system and component concepts are defined that include micro-actuated adaptive optics, micromachined inertial sensors, fiber-optic data nets and light-power transmission, and VLSI microcomputers. The thesis is advanced that these micro-miniaturization products are capable of having a revolutionary impact on space missions and systems, and that GN&C is the pathfinder micro-technology application that can bring that about.

Micro-engineered remote palpation device for assessing tissue compliance.

PubMed

Hien, M; Yang, T H J; Leung, S K W; Reuben, R L; Habib, F K; McNeill, S A; Schneider, A; McBride, G; Stevens, R; Else, R W

2008-01-01

This paper concerns the operation of the actuator for a prototype micro-engineered mechanical palpation device for deployment via a cystoscope to measure the dynamic mechanical properties of the prostate gland in vivo. The subassembly consists of a 400x200 microm silicon (Si) piston manufactured using deep reactive ion etching (DRIE) housed within an anodically bonded glass-Si-glass sandwiched housing. The micro-channel on the Si layer was formed by powder blasting and contains the micro-piston with one end pointing to the side of the housing and the other facing a via hole leading to a capillary tube. The opening on the side of the housing was sealed by a 5 microm thick silicone membrane which acts to retain the micro-piston and act as a return spring. A 320 microm diameter capillary forms the connection between the micro-channel and a micro-syringe which is operated by a programmable syringe pump to produce a reciprocating action. A pressure sensor is connected along the capillary tube to measure the dynamic pressure within the system. The micro-piston has already been used, separately actuated to measure the dynamic mechanical properties of known viscoelastic materials and prostate tissue. The purpose of the present work is to assess the functionality of the actuator assembly.

Utilization of Stop-flow Micro-tubing Reactors for the Development of Organic Transformations.

PubMed

Toh, Ren Wei; Li, Jie Sheng; Wu, Jie

2018-01-04

A new reaction screening technology for organic synthesis was recently demonstrated by combining elements from both continuous micro-flow and conventional batch reactors, coined stop-flow micro-tubing (SFMT) reactors. In SFMT, chemical reactions that require high pressure can be screened in parallel through a safer and convenient way. Cross-contamination, which is a common problem in reaction screening for continuous flow reactors, is avoided in SFMT. Moreover, the commercially available light-permeable micro-tubing can be incorporated into SFMT, serving as an excellent choice for light-mediated reactions due to a more effective uniform light exposure, compared to batch reactors. Overall, the SFMT reactor system is similar to continuous flow reactors and more superior than batch reactors for reactions that incorporate gas reagents and/or require light-illumination, which enables a simple but highly efficient reaction screening system. Furthermore, any successfully developed reaction in the SFMT reactor system can be conveniently translated to continuous-flow synthesis for large scale production.

Designing the Very Small: Micro and Nanotechnology. Resources in Technology.

ERIC Educational Resources Information Center

Jacobs, James A.

1996-01-01

This learning activity is designed to increase knowledge of materials science; engineering; and technology design and the manufacture of the very small devices used in watches, computers, and calculators. It looks at possible innovations to come from micro- and nanotechnology. Includes a student quiz. (Author/JOW)

NASA's In-Space Manufacturing Project: Materials and Manufacturing Process Development Update

NASA Technical Reports Server (NTRS)

Prater, Tracie; Bean, Quincy; Werkheiser, Niki; Ledbetter, Frank

2017-01-01

The mission of NASA's In-Space Manufacturing (ISM) project is to identify, design, and implement on-demand, sustainable manufacturing solutions for fabrication, maintenance and repair during exploration missions. ISM has undertaken a phased strategy of incrementally increasing manufacturing capabilities to achieve this goal. The ISM project began with the development of the first 3D printer for the International Space Station. To date, the printer has completed two phases of flight operations. Results from phase I specimens indicated some differences in material properties between ground-processed and ISS-processed specimens, but results of follow-on analyses of these parts and a ground-based study with an equivalent printer strongly indicate that this variability is likely attributable to differences in manufacturing process settings between the ground and flight prints rather than microgravity effects on the fused deposition modeling (FDM) process. Analysis of phase II specimens from the 3D Printing in Zero G tech demo, which shed further light on the sources of material variability, will be presented. The ISM project has also developed a materials characterization plan for the Additive Manufacturing Facility, the follow-on commercial multimaterial 3D printing facility developed for ISS by Made in Space. This work will yield a suite of characteristic property values that can inform use of AMF by space system designers. Other project activities include development of an integrated 3D printer and recycler, known as the Refabricator, by Tethers Unlimited, which will be operational on ISS in 2018. The project also recently issued a broad area announcement for a multimaterial fabrication laboratory, which may include in-space manufacturing capabilities for metals, electronics, and polymeric materials, to be deployed on ISS in the 2022 timeframe.

Micromachined edge illuminated optically transparent automotive light guide panels

NASA Astrophysics Data System (ADS)

Ronny, Rahima Afrose; Knopf, George K.; Bordatchev, Evgueni; Tauhiduzzaman, Mohammed; Nikumb, Suwas

2012-03-01

Edge-lit backlighting has been used extensively for a variety of small and medium-sized liquid crystal displays (LCDs). The shape, density and spatial distribution pattern of the micro-optical elements imprinted on the surface of the flat light-guide panel (LGP) are often "optimized" to improve the overall brightness and luminance uniformity. A similar concept can be used to develop interior convenience lighting panels and exterior tail lamps for automotive applications. However, costly diffusive sheeting and brightness enhancement films are not be considered for these applications because absolute luminance uniformity and the minimization of Moiré fringe effects are not significant factors in assessing quality of automotive lighting. A new design concept that involves micromilling cylindrical micro-optical elements on optically transparent plastic substrates is described in this paper. The variable parameter that controls illumination over the active regions of the panel is the depth of the individual cylindrical micro-optical elements. LightTools™ is the optical simulation tool used to explore how changing the micro-optical element depth can alter the local and global luminance. Numerical simulation and microfabrication experiments are performed on several (100mmx100mmx6mm) polymethylmethacrylate (PMMA) test samples in order to verify the illumination behavior.

Ultraprecision finishing of micro-aspherical surface by ultrasonic assisted polishing; Technical Digest

NASA Astrophysics Data System (ADS)

Suzuki, Hirofumi; Kawamori, Ryota; Yamamoto, Yuji; Miyabara, Mitsuru; Okino, Tadashi; Hijikata, Yoshio; Moriwaki, Toshimichi

2005-05-01

Micro aspherical glass lenses are required for electronic devices, optical devices and advanced optical fiber transmission equipments. The glass lenses are manufactured by glass molding method by using micro ceramics dies such as tungsten carbide or silicon carbide (1). Therefore molding dies are most important and they were ground by ultra-precision grinding method with diamond wheel. Recently, the wavelength of used laser is becoming shorter and then the accuracies of the micro molding die are required to be much more precise (2). In this paper, ultrasonic assisted polishing methods/systems were developed in order to finish micro aspherical dies that were ground with micro diamond wheel. In the polishing experiments, the molding die of tungsten carbide was polished with diamond abrasives to test the basic polishing characteristics and the aspheric die was polished with proposed ultrasonic assisted polishing method.

Mapping lightscapes: spatial patterning of artificial lighting in an urban landscape.

PubMed

Hale, James D; Davies, Gemma; Fairbrass, Alison J; Matthews, Thomas J; Rogers, Christopher D F; Sadler, Jon P

2013-01-01

Artificial lighting is strongly associated with urbanisation and is increasing in its extent, brightness and spectral range. Changes in urban lighting have both positive and negative effects on city performance, yet little is known about how its character and magnitude vary across the urban landscape. A major barrier to related research, planning and governance has been the lack of lighting data at the city extent, particularly at a fine spatial resolution. Our aims were therefore to capture such data using aerial night photography and to undertake a case study of urban lighting. We present the finest scale multi-spectral lighting dataset available for an entire city and explore how lighting metrics vary with built density and land-use. We found positive relationships between artificial lighting indicators and built density at coarse spatial scales, whilst at a local level lighting varied with land-use. Manufacturing and housing are the primary land-use zones responsible for the city's brightly lit areas, yet manufacturing sites are relatively rare within the city. Our data suggests that efforts to address light pollution should broaden their focus from residential street lighting to include security lighting within manufacturing areas.

Mapping Lightscapes: Spatial Patterning of Artificial Lighting in an Urban Landscape

PubMed Central

Hale, James D.; Davies, Gemma; Fairbrass, Alison J.; Matthews, Thomas J.; Rogers, Christopher D. F.; Sadler, Jon P.

2013-01-01

Artificial lighting is strongly associated with urbanisation and is increasing in its extent, brightness and spectral range. Changes in urban lighting have both positive and negative effects on city performance, yet little is known about how its character and magnitude vary across the urban landscape. A major barrier to related research, planning and governance has been the lack of lighting data at the city extent, particularly at a fine spatial resolution. Our aims were therefore to capture such data using aerial night photography and to undertake a case study of urban lighting. We present the finest scale multi-spectral lighting dataset available for an entire city and explore how lighting metrics vary with built density and land-use. We found positive relationships between artificial lighting indicators and built density at coarse spatial scales, whilst at a local level lighting varied with land-use. Manufacturing and housing are the primary land-use zones responsible for the city’s brightly lit areas, yet manufacturing sites are relatively rare within the city. Our data suggests that efforts to address light pollution should broaden their focus from residential street lighting to include security lighting within manufacturing areas. PMID:23671566

Inspection of additive manufactured parts using laser ultrasonics

NASA Astrophysics Data System (ADS)

Lévesque, D.; Bescond, C.; Lord, M.; Cao, X.; Wanjara, P.; Monchalin, J.-P.

2016-02-01

Additive manufacturing is a novel technology of high importance for global sustainability of resources. As additive manufacturing involves typically layer-by-layer fusion of the feedstock (wire or powder), an important characteristic of the fabricated metallic structural parts, such as those used in aero-engines, is the performance, which is highly related to the presence of defects, such as cracks, lack of fusion or bonding between layers, and porosity. For this purpose, laser ultrasonics is very attractive due to its non-contact nature and is especially suited for the analysis of parts of complex geometries. In addition, the technique is well adapted to online implementation and real-time measurement during the manufacturing process. The inspection can be performed from either the top deposited layer or the underside of the substrate and the defects can be visualized using laser ultrasonics combined with the synthetic aperture focusing technique (SAFT). In this work, a variety of results obtained off-line on INCONEL® 718 and Ti-6Al-4V coupons that were manufactured using laser powder, laser wire, or electron beam wire deposition are reported and most defects detected were further confirmed by X-ray micro-computed tomography.

Evaluation of hybrid polymers for high-precision manufacturing of 3D optical interconnects by two-photon absorption lithography

NASA Astrophysics Data System (ADS)

Schleunitz, A.; Klein, J. J.; Krupp, A.; Stender, B.; Houbertz, R.; Gruetzner, G.

2017-02-01

The fabrication of optical interconnects has been widely investigated for the generation of optical circuit boards. Twophoton absorption (TPA) lithography (or high-precision 3D printing) as an innovative production method for direct manufacture of individual 3D photonic structures gains more and more attention when optical polymers are employed. In this regard, we have evaluated novel ORMOCER-based hybrid polymers tailored for the manufacture of optical waveguides by means of high-precision 3D printing. In order to facilitate future industrial implementation, the processability was evaluated and the optical performance of embedded waveguides was assessed. The results illustrate that hybrid polymers are not only viable consumables for industrial manufacture of polymeric micro-optics using generic processes such as UV molding. They also are potential candidates to fabricate optical waveguide systems down to the chip level where TPA-based emerging manufacturing techniques are engaged. Hence, it is shown that hybrid polymers continue to meet the increasing expectations of dynamically growing markets of micro-optics and optical interconnects due to the flexibility of the employed polymer material concept.

New concepts and materials for the manufacturing of MR-compatible guide wires.

PubMed

Brecher, Christian; Emonts, Michael; Brack, Alexander; Wasiak, Christian; Schütte, Adrian; Krämer, Nils; Bruhn, Robin

2014-04-01

This paper shows the development of a new magnetic resonance imaging (MRI)-compatible guide wire made from fiber-reinforced plastics. The basic material of the developed guide wire is manufactured using a specially developed micro-pullwinding technology, which allows the adjustment of tensile, bending, and torsional stiffness independent from each other. Additionally, the micro-pullwinding technology provides the possibility to vary the stiffness along the length of the guide wire in a continuous process. With the possibilities of this technology, the mechanical properties of the guide wire were precisely adjusted for the intended usage in MRI-guided interventions. The performance of the guide wire regarding the mechanical properties was investigated. It could be shown, that the mechanical properties could be changed independently from each other by varying the process parameters. Especially, the torsional stiffness could be significantly improved with only a minor influence on bending and tensile properties. The precise influence of the variation of the winding angle on the mechanical and geometrical properties has to be further investigated. The usability of the guide wire as well as its visibility in MRI was investigated by radiologists. With the micro-pullwinding technology, a continuous manufacturing technique for highly stressable, MRI-safe profiles is available and can be the trigger for a new class of medical devices.

Utilizing dynamic light scattering as a process analytical technology for protein folding and aggregation monitoring in vaccine manufacturing.

PubMed

Yu, Zhou; Reid, Jennifer C; Yang, Yan-Ping

2013-12-01

Protein aggregation is a common challenge in the manufacturing of biological products. It is possible to minimize the extent of aggregation through timely measurement and in-depth characterization of aggregation. In this study, we demonstrated the use of dynamic light scattering (DLS) to monitor inclusion body (IB) solubilization, protein refolding, and aggregation near the production line of a recombinant protein-based vaccine candidate. Our results were in good agreement with those measured by size-exclusion chromatography. DLS was also used to characterize the mechanism of aggregation. As DLS is a quick, nonperturbing technology, it can potentially be used as an at-line process analytical technology to ensure complete IB solubilization and aggregate-free refolding. © 2013 Wiley Periodicals, Inc. and the American Pharmacists Association.

Effect of Red Light-Emitting Diodes Irradiation on Hemoglobin for Potential Hypertension Treatment Based on Confocal Micro-Raman Spectroscopy.

PubMed

Qiu, Xuejun; Huang, Hanchuan; Huang, Zhitong; Zhuang, Zhengfei; Guo, Zhouyi; Liu, Songhao

2017-01-01

Red light-emitting diodes (LED) were used to irradiate the isolated hypertension hemoglobin (Hb) and Raman spectra difference was recorded using confocal micro-Raman spectroscopy. Differences were observed between the controlled and irradiated Hb by comparing the spectra records. The Raman spectrum at the 1399 cm -1 band decreased following prolonged LED irradiation. The intensity of the 1639 cm -1 band decreased dramatically in the first five minutes and then gradually increased in a time-dependent manner. This observation indicated that LED irradiation increased the ability of oxygen binding in Hb. The appearance of the heme aggregation band at 1399 cm -1 , in addition to the oxygen marker band at 1639 cm -1 , indicated that, in our study, 30 min of irradiation with 15.0 mW was suitable for inhibiting heme aggregation and enhancing the oxygen-carrying capacity of Hb. Principal component analysis showed a one-to-one relationship between irradiated Hb at different time points and the corresponding Raman spectra. Our approach could be used to analyze the hemoglobin from patients with confocal micro-Raman spectroscopy and is helpful for developing new nondrug hypertension therapy.

Development of the micro pixel chamber based on MEMS technology

NASA Astrophysics Data System (ADS)

Takemura, T.; Takada, A.; Kishimoto, T.; Komura, S.; Kubo, H.; Matsuoka, Y.; Miuchi, K.; Miyamoto, S.; Mizumoto, T.; Mizumura, Y.; Motomura, T.; Nakamasu, Y.; Nakamura, K.; Oda, M.; Ohta, K.; Parker, J. D.; Sawano, T.; Sonoda, S.; Tanimori, T.; Tomono, D.; Yoshikawa, K.

2018-02-01

Micro pixel chambers (μ-PIC) are gaseous two-dimensional imaging detectors originally manufactured using printed circuit board (PCB) technology. They are used in MeV gamma-ray astronomy, medicalimaging, neutron imaging, the search for dark matter, and dose monitoring. The position resolution of the present μ-PIC is approximately 120 μm (RMS), however some applications require a fine position resolution of less than 100 μm. To this end, we have started to develop a μ-PIC based on micro electro mechanical system (MEMS) technology, which provides better manufacturing accuracy than PCB technology. Our simulation predicted the gains of MEMS μ-PICs to be twice those of PCB μ-PICs at the same anode voltage. We manufactured two MEMS μ-PICs and tested them to study their behavior. In these experiments, we successfully operated the fabricatedMEMS μ-PICs and we achieved a maximum gain of approximately 7×103 and collected their energy spectra under irradiation of X-rays from 55Fe. However, the measured gains of the MEMS μ-PICs were less than half of the values predicted in the simulations. We postulated that the gains of the MEMS μ-PICs are diminished by the effect of the silicon used as a semiconducting substrate.

Textural Evolution During Micro Direct Metal Deposition of NiTi Alloy

NASA Astrophysics Data System (ADS)

Khademzadeh, Saeed; Bariani, Paolo F.; Bruschi, Stefania

2018-03-01

In this research, a micro direct metal deposition process, newly developed as a potential method for micro additive manufacturing was used to fabricate NiTi builds. The effect of scanning strategy on grain growth and textural evolution was investigated using scanning electron microscope equipped with electron backscattered diffraction detector. Investigations showed that, the angle between the successive single tracks has an important role in grain size distribution and textural evolution of NiTi phase. Unidirectional laser beam scanning pattern developed a fiber texture; conversely, a backward and forward scanning pattern developed a strong < {100} > ‖‖ RD texture on the surface of NiTi cubic samples produced by micro direct metal deposition.

Textural Evolution During Micro Direct Metal Deposition of NiTi Alloy

NASA Astrophysics Data System (ADS)

Khademzadeh, Saeed; Bariani, Paolo F.; Bruschi, Stefania

2018-07-01

In this research, a micro direct metal deposition process, newly developed as a potential method for micro additive manufacturing was used to fabricate NiTi builds. The effect of scanning strategy on grain growth and textural evolution was investigated using scanning electron microscope equipped with electron backscattered diffraction detector. Investigations showed that, the angle between the successive single tracks has an important role in grain size distribution and textural evolution of NiTi phase. Unidirectional laser beam scanning pattern developed a fiber texture; conversely, a backward and forward scanning pattern developed a strong < {100} > ‖‖ RD texture on the surface of NiTi cubic samples produced by micro direct metal deposition.

Micro-chemical and micro-structural investigation of archaeological bronze weapons from the Ayanis fortress (lake Van, Eastern Anatolia, Turkey)

NASA Astrophysics Data System (ADS)

Faraldi, F.; Çilingirǒglu, A.; Angelini, E.; Riccucci, C.; De Caro, T.; Batmaz, A.; Mezzi, A.; Caschera, D.; Cortese, B.

2013-12-01

Bronze weapons (VII cen BC) found during the archaeological excavation of the Ayanis fortress (lake Van, eastern Anatolia, Turkey) are investigated in order to determine their chemical composition and metallurgical features as well as to identify the micro-chemical and micro-structural nature of the corrosion products grown during long-term burial. Small fragments were sampled from the artefacts and analysed by means of the combined use of optical microscopy (OM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS). The results show that the bronze artefacts have been manufactured by using alloys with a controlled and refined chemical composition demonstrating the high level metallurgical competence and skill of the Urartian craftsmen and artists. Furthermore, the micro-structural and metallurgical investigations evidence the presence of equiaxed grains in the matrix, indicating that the artefact were produced by repeated cycles of mechanical shaping and thermal annealing treatments to restore the alloy ductility. From the degradation point of view, the results show the structures and the chemical composition of the stratified corrosion layers (i.e. the patina) where the copper or tin depletion phenomenon is commonly observed with the surface enrichment of some elements coming from the burial soil, mainly Cl, which is related to the high concentration of chlorides in the Ayanis soil. The results reveal also that another source of degradation is the inter-granular corrosion phenomenon likely increased by the metallurgical features of the alloys caused by the high temperature manufacturing process that induces crystallisation and segregation phenomena along the grain boundaries.

Direct laser writing for micro-optical devices using a negative photoresist.

PubMed

Tsutsumi, Naoto; Hirota, Junichi; Kinashi, Kenji; Sakai, Wataru

2017-12-11

Direct laser writing (DLW) via two-photon absorption (TPA) has attracted much attention as a new microfabrication technique because it can be applied to fabricate complex, three-dimensional (3D) microstructures. In this study, 3D microstructures and micro-optical devices of micro-lens array on the micrometer scale are fabricated using the negative photoresist SU-8 through TPA with a femtosecond laser pulse under a microscope. The effects of the irradiation conditions on linewidths, such as laser power, writing speed, and writing cycles (a number of times a line is overwritten), are investigated before the fabrication of the 3D microstructures. Various microstructures such as woodpiles, hemisphere and microstructures, 3D micro-lens and micro-lens array for micro-optical devices are fabricated. The shape of the micro-lens is evaluated using the shape analysis mode of a laser microscope to calculate the working distance of the fabricated micro-lenses. The calculated working distance corresponds well to the experimentally measured value. The focusing performance of the fabricated micro-lens is confirmed by the TPA fluorescence of an isopropyl thioxanthone (ITX) ethanol solution excited by a Ti:sapphire femtosecond laser at 800 nm. Micro-lens array (assembled 9 micro-lenses) are fabricated. Nine independent woodpile structures are simultaneously manufactured by DLW via TPA to confirm the multi-focusing ability using the fabricated micro-lens array.

Manufacturer Tier 3 Questions and EPA Answers

EPA Pesticide Factsheets

This document contains a record of EPA responses to manufacturer questions received prior to October 16, 2015 with respect to implementation of the Tier 3 final rule intended to aid regulated parties in achieving compliance with regulations for light-duty

Validating continuous digital light processing (cDLP) additive manufacturing accuracy and tissue engineering utility of a dye-initiator package.

PubMed

Wallace, Jonathan; Wang, Martha O; Thompson, Paul; Busso, Mallory; Belle, Vaijayantee; Mammoser, Nicole; Kim, Kyobum; Fisher, John P; Siblani, Ali; Xu, Yueshuo; Welter, Jean F; Lennon, Donald P; Sun, Jiayang; Caplan, Arnold I; Dean, David

2014-03-01

This study tested the accuracy of tissue engineering scaffold rendering via the continuous digital light processing (cDLP) light-based additive manufacturing technology. High accuracy (i.e., <50 µm) allows the designed performance of features relevant to three scale spaces: cell-scaffold, scaffold-tissue, and tissue-organ interactions. The biodegradable polymer poly (propylene fumarate) was used to render highly accurate scaffolds through the use of a dye-initiator package, TiO2 and bis (2,4,6-trimethylbenzoyl)phenylphosphine oxide. This dye-initiator package facilitates high accuracy in the Z dimension. Linear, round, and right-angle features were measured to gauge accuracy. Most features showed accuracies between 5.4-15% of the design. However, one feature, an 800 µm diameter circular pore, exhibited a 35.7% average reduction of patency. Light scattered in the x, y directions by the dye may have reduced this feature's accuracy. Our new fine-grained understanding of accuracy could be used to make further improvements by including corrections in the scaffold design software. Successful cell attachment occurred with both canine and human mesenchymal stem cells (MSCs). Highly accurate cDLP scaffold rendering is critical to the design of scaffolds that both guide bone regeneration and that fully resorb. Scaffold resorption must occur for regenerated bone to be remodeled and, thereby, achieve optimal strength.

Characterization of Propylene Glycol-Mitigated Freeze/Thaw Agglomeration of a Frozen Liquid nOMV Vaccine Formulation by Static Light Scattering and Micro-Flow Imaging.

PubMed

Mensch, Christopher D; Davis, Harrison B; Blue, Jeffrey T

2015-01-01

The purpose of this work was to investigate the susceptibility of an aluminum adjuvant and an aluminum-adjuvanted native outer membrane vesicle (nOMV) vaccine formulation to freeze/thaw-induced agglomeration using static light scattering and micro-flow Imaging analysis; and to evaluate the use of propylene glycol as a vaccine formulation excipient by which freeze/thaw-induced agglomeration of a nOMV vaccine formulation could be mitigated. Our results indicate that including 7% v/v propylene glycol in an nOMV containing aluminum adjuvanted vaccine formulation, mitigates freeze/thaw-induced agglomeration. We evaluated the effect of freeze-thawing on an aluminum adjuvant and an aluminum adjuvanted native outer membrane vesicle (nOMV) vaccine formulation. Specifically, we characterized the freeze/thaw-induced agglomeration through the use of static light scattering, micro-flow imaging, and cryo-electron microscopy analysis. Further, we evaluated the use of 0-9% v/v propylene glycol as an excipient which could be included in the formulation for the purpose of mitigating the agglomeration induced by freeze/thaw. The results indicate that using 7% v/v propylene glycol as a formulation excipient is effective at mitigating agglomeration of the nOMV vaccine formulation, otherwise induced by freeze-thawing. © PDA, Inc. 2015.

Imaging birefringent crystals using micro optical coherence tomography (Conference Presentation)

NASA Astrophysics Data System (ADS)

Sharma, Gargi; Singh, Kanwarpal; Gardecki, Joseph A.; Tearney, Guillermo J.

2017-02-01

Background: Uric acid crystals have recently been identified as a possible therapeutic target for coronary artery disease. Being subcellular in size, it is difficult to identify these crystals in situ. Micro optical coherence tomography (Micro-OCT) allows one to image subcellular structures with 1-micron resolution. Even though Micro-OCT should be capable of resolving urate crystals, it's difficult to differentiate these structures from other scattering particles within tissue. In this work we developed a novel polarization sensitive micro OCT (ps-Micro-OCT) system for identification of uric acid crystals. Methods: A spectrometer based ps-Micro-OCT system was developed using a broadband light source. The broadband input light was divided into reference and sample signals using a beam splitter. The reference signal was further divided into two polarized signals with different polarization states. Reflected reference and sample signals were combined and sent to a spectrometer that recorded the interference signal. Results: To test the performance of system, a mirror was used as sample and a quarter wave-plate was placed in the sample path. The measured quarter wave-plate angle values matched closely to actual angle values. Next we prepared uric acid crystals in our lab and imaged them using this system.We were able to image and identify these crystals based on polarization measurements. Conclusion: In this work we imaged and identified uric acid crystals using a newly developed ps-Micro-OCT system. The proposed technique will enable imaging uric acid crystals in coronary artery.

Analysis of the reflection of a micro drop fiber sensor

NASA Astrophysics Data System (ADS)

Sun, Weimin; Liu, Qiang; Zhao, Lei; Li, Yingjuan; Yuan, Libo

2005-01-01

Micro drop fiber sensors are effective tools for measuring characters of liquids. These types of sensors are wildly used in biotechnology, beverage and food markets. For a fiber micro drop sensor, the signal of the output light is wavy with two peaks, normally. Carefully analyzing the wavy process can identify the liquid components. Understanding the reason of forming this wavy signal is important to design a suitable sensing head and to choose a suitable signal-processing method. The dripping process of a type of liquids is relative to the characters of the liquid and the shape of the sensing head. The quasi-Gauss model of the light field from the input-fiber end is used to analyse the distribution of the light field in the liquid drop. In addition, considering the characters of the liquid to be measured, the dripping process of the optical signal from the output-fiber end can be expected. The reflection surface of the micro drop varies as serials of spheres with different radiuses and global centers. The intensity of the reflection light changes with the shape of the surface. The varying process of the intensity relates to the tense, refractive index, transmission et al. To support the analyse above, an experimental system is established. In the system, LED is chosen as the light source and the PIN transform the light signal to the electrical signal, which is collected by a data acquisition card. An on-line testing system is made to check the theory discussed above.

Photovoltaic device with increased light absorption and method for its manufacture

DOEpatents

Glatfelter, Troy; Vogeli, Craig; Call, Jon; Hammond, Ginger

1993-07-20

A photovoltaic cell having a light-directing optical element integrally formed in an encapsulant layer thereof. The optical element redirects light to increase the internal absorption of light incident on the photovoltaic device.

Enabling laser applications in microelectronics manufacturing

NASA Astrophysics Data System (ADS)

Delmdahl, Ralph; Brune, Jan; Fechner, Burkhard; Senczuk, Rolf

2016-02-01

In this experimental study, we report on high-pulse-energy excimer laser drilling into high-performance build-up films which are pivotal in microelectronics manufacturing. Build-up materials ABF-GX13 from Ajinomoto as well as ZS-100 from Zeon Corporation are evaluated with respect to their viability for economic excimer laser-based micro-via formation. Excimer laser mask imaging projection at laser wavelengths of 193, 248 and 308 nm is employed to generate matrices of smaller micro-vias with different diameters and via pitches. High drilling quality is achievable for all excimer laser wavelengths with the fastest ablation rates measured in the case of 248 and 308 nm wavelengths. The presence of glass fillers in build-up films as in the ABF-GX13 material poses some limitations to the minimum achievable via diameter. However, surprisingly good drilling results are obtainable as long as the filler dimensions are well below the diameter of the micro-vias. Sidewall angles of vias are controllable by adjusting the laser energy density and pulse number. In this work, the structuring capabilities of excimer lasers in build-up films as to taper angle variations, attainable via diameters, edge-stop behavior and ablation rates will be elucidated.

Automatic Detection and Evaluation of Solar Cell Micro-Cracks in Electroluminescence Images Using Matched Filters

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

Spataru, Sergiu; Hacke, Peter; Sera, Dezso

A method for detecting micro-cracks in solar cells using two dimensional matched filters was developed, derived from the electroluminescence intensity profile of typical micro-cracks. We describe the image processing steps to obtain a binary map with the location of the micro-cracks. Finally, we show how to automatically estimate the total length of each micro-crack from these maps, and propose a method to identify severe types of micro-cracks, such as parallel, dendritic, and cracks with multiple orientations. With an optimized threshold parameter, the technique detects over 90 % of cracks larger than 3 cm in length. The method shows great potentialmore » for quantifying micro-crack damage after manufacturing or module transportation for the determination of a module quality criterion for cell cracking in photovoltaic modules.« less

Direct laser writing of polymer micro-ring resonator ultrasonic sensors

NASA Astrophysics Data System (ADS)

Wei, Heming; Krishnaswamy, Sridhar

2017-04-01

With the development of photoacoustic technology in recent years, ultrasound-related sensors play a vital role in a number of areas ranging from scientific research to nondestructive testing. Compared with the traditional PZT transducer as ultrasonic sensors, novel ultrasonic sensors based on optical methods such as micro-ring resonators have gained increasing attention. The total internal reflection of the light along the cavity results in light propagating in microcavities as whispering gallery modes (WGMs), which are extremely sensitive to change in the radius and refractive index of the cavity induced by ultrasound strain field. In this work, we present a polymer optical micro-ring resonator based ultrasonic sensor fabricated by direct laser writing optical lithography. The design consists of a single micro-ring and a straight tapered waveguide that can be directly coupled by single mode fibers (SMFs). The design and fabrication of the printed polymer resonator have been optimized to provide broad bandwidth and high optical quality factor to ensure high detection sensitivity. The experiments demonstrate the potential of the polymer micro-ring resonator to works as a high-performance ultrasonic sensor.

Research, Development and Demonstration of Micro-CHP Systems for Residential Applications - Phase I

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

Robert A. Zogg

The objective of the Micro-CHP Phase I effort was to develop a conceptual design for a Micro-CHP system including: Defining market potential; Assessing proposed technology; Developing a proof-of-principle design; and Developing a commercialization strategy. TIAX LLC assembled a team to develop a Micro-CHP system that will provide electricity and heating. TIAX, the contractor and major cost-share provider, provided proven expertise in project management, prime-mover design and development, appliance development and commercialization, analysis of residential energy loads, technology assessment, and market analysis. Kohler Company, the manufacturing partner, is a highly regarded manufacturer of standby power systems and other residential products. Kohlermore » provides a compellingly strong brand, along with the capabilities in product development, design, manufacture, distribution, sales, support, service, and marketing that only a manufacturer of Kohler's status can provide. GAMA, an association of appliance and equipment manufacturers, provided a critical understanding of appliance commercialization issues, including regulatory requirements, large-scale market acceptance issues, and commercialization strategies. The Propane Education & Research Council, a cost-share partner, provided cost share and aided in ensuring the fuel flexibility of the conceptual design. Micro-CHP systems being commercialized in Europe and Japan are generally designed to follow the household thermal load, and generate electricity opportunistically. In many cases, any excess electricity can be sold back to the grid (net metering). These products, however, are unlikely to meet the demands of the U.S. market. First, these products generally cannot provide emergency power when grid power is lost--a critical feature to market success in the U.S. Even those that can may have insufficient electric generation capacities to meet emergency needs for many U.S. homes. Second, the extent to which net

New analysis strategies for micro aspheric lens metrology

NASA Astrophysics Data System (ADS)

Gugsa, Solomon Abebe

Effective characterization of an aspheric micro lens is critical for understanding and improving processing in micro-optic manufacturing. Since most microlenses are plano-convex, where the convex geometry is a conic surface, current practice is often limited to obtaining an estimate of the lens conic constant, which average out the surface geometry that departs from an exact conic surface and any addition surface irregularities. We have developed a comprehensive approach of estimating the best fit conic and its uncertainty, and in addition propose an alternative analysis that focuses on surface errors rather than best-fit conic constant. We describe our new analysis strategy based on the two most dominant micro lens metrology methods in use today, namely, scanning white light interferometry (SWLI) and phase shifting interferometry (PSI). We estimate several parameters from the measurement. The major uncertainty contributors for SWLI are the estimates of base radius of curvature, the aperture of the lens, the sag of the lens, noise in the measurement, and the center of the lens. In the case of PSI the dominant uncertainty contributors are noise in the measurement, the radius of curvature, and the aperture. Our best-fit conic procedure uses least squares minimization to extract a best-fit conic value, which is then subjected to a Monte Carlo analysis to capture combined uncertainty. In our surface errors analysis procedure, we consider the surface errors as the difference between the measured geometry and the best-fit conic surface or as the difference between the measured geometry and the design specification for the lens. We focus on a Zernike polynomial description of the surface error, and again a Monte Carlo analysis is used to estimate a combined uncertainty, which in this case is an uncertainty for each Zernike coefficient. Our approach also allows us to investigate the effect of individual uncertainty parameters and measurement noise on both the best

Sentences. MicroSIFT Courseware Evaluation.

ERIC Educational Resources Information Center

Northwest Regional Educational Lab., Portland, OR.

THE FOLLOWING IS THE FULL TEXT OF THIS DOCUMENT (Except for the Evaluation Summary Table): VERSION: Apple II. PRODUCER: Micro Power & Light Company, 12820 Hillcrest Rd., Suite 224, Dallas, Texas 75230. EVALUATION COMPLETED: June 1982 by the staff and constituents of the Portland Public Schools, Multnomah ESD, Portland, Oregon. COST: $24.95.…

40 CFR 86.1838-01 - Small-volume manufacturer certification procedures.

Code of Federal Regulations, 2014 CFR

2014-07-01

... AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto-Cycle Heavy-Duty Vehicles § 86.1838-01 Small-volume manufacturer...

Responsive upper limb and cognitive fatigue measures during light precision work: an 8-hour simulated micro-pipetting study.

PubMed

Yung, Marcus; Wells, Richard P

2017-07-01

Many contemporary occupations are characterised by long periods of low loads. These lower force levels, which are relevant to the development of work-related musculoskeletal disorders, are usually not the focus of fatigue studies. In studies that did measure fatigue in light manual or precision work, within and between measurement responses were inconsistent. The aim of this study was to identify fatigue measures that were responsive at lower force levels (<10% MVC) over the course of an 8-h period. A complementary set of fatigue measures, reflecting both neuromuscular and cognitive mechanisms, was measured during a light precision micro-pipetting task performed by 11 participants. Nine measures were found to be significantly responsive over the 8-h period, including: ratings of perceived fatigue, postural tremor, blink frequency and critical flicker fusion frequency threshold. Common field measures, specifically electromyography RMS amplitude and maximum voluntary contractions, did not lead to extraordinary time effects. Practitioner summary: The findings provide insight towards the responsiveness of a complementary set of field usable fatigue measures at low work intensities Although commonly used measures did not reveal significant increases in fatigue, nine alternative measures were significantly responsive over the 8-h period.

Manufacturing Process for OLED Integrated Substrate

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

Hung, Cheng-Hung; McCamy, James; Ashtosh, Ganjoo

2017-01-27

The primary objective of this project is to demonstrate manufacturing processes for technologies that will enable commercialization of a large-area and low-cost “integrated substrate” product for rigid OLED SSL lighting. The integrated substrate product will consist of a low cost, float glass substrate combined with a transparent conductive anode film layer, and light out-coupling (internal and external extraction layers) structures. In combination, these design elements will enable an integrated substrate meeting or exceeding 2015 performance targets for cost ($60/m2), extraction efficiency (50%) and sheet resistance (<10 ohm/sq).

Characterization of a calcium/calmodulin-dependent protein kinase homolog from maize roots showing light-regulated gravitropism

NASA Technical Reports Server (NTRS)

Lu, Y. T.; Hidaka, H.; Feldman, L. J.

1996-01-01

Roots of many species respond to gravity (gravitropism) and grow downward only if illuminated. This light-regulated root gravitropism is phytochrome-dependent, mediated by calcium, and inhibited by KN-93, a specific inhibitor of calcium/calmodulin-dependent protein kinase II (CaMK II). A cDNA encoding MCK1, a maize homolog of mammalian CaMK, has been isolated from roots of maize (Zea mays L.). The MCK1 gene is expressed in root tips, the site of perception for both light and gravity. Using the [35S]CaM gel-overlay assay we showed that calmodulin-binding activity of the MCK1 is abolished by 50 microM KN-93, but binding is not affected by 5 microM KN-93, paralleling physiological findings that light-regulated root gravitropism is inhibited by 50 microM KN-93, but not by 5 microM KN-93. KN-93 inhibits light-regulated gravitropism by interrupting transduction of the light signal, not light perception, suggesting that MCK1 may play a role in transducing light. This is the first report suggesting a physiological function for a CaMK homolog in light signal transduction.

Image Quality Performance Measurement of the microPET Focus 120

NASA Astrophysics Data System (ADS)

Ballado, Fernando Trejo; López, Nayelli Ortega; Flores, Rafael Ojeda; Ávila-Rodríguez, Miguel A.

2010-12-01

The aim of this work is to evaluate the characteristics involved in the image reconstruction of the microPET Focus 120. For this evaluation were used two different phantoms; a miniature hot-rod Derenzo phantom and a National Electrical Manufacturers Association (NEMA) NU4-2008 image quality (IQ) phantom. The best image quality was obtained when using OSEM3D as the reconstruction method reaching a spatial resolution of 1.5 mm with the Derenzo phantom filled with 18F. Image quality test results indicate a superior image quality for the Focus 120 when compared to previous microPET models.

The effect of three whitening oral rinses on enamel micro-hardness.

PubMed

Potgieter, E; Osman, Y; Grobler, S R

2014-05-01

The purpose of this study was to determine the effect on human enamel micro-hardness of three over-the-counter whitening oral rinses available in South Africa. Enamel fragments were gathered into three groups of 15 each. One group was exposed to Colgate Plax Whitening Blancheur, the second group to White Glo 2 in 1 and the third to Plus White, in each case for periods recommended by the respective manufacturers. Surface micro-hardness of all groups was measured before and after a 14 day treatment period. pH levels of the oral rinses were also determined with a combination pH electrode. Pre- and post- treatment data were analysed by the Wilcoxon Signed Rank Sum Test. According to the micro-hardness values no significant (p > 0.05) enamel damage was found as a result of treatment. However, it was observed that Colgate Pax and White Glo decreased the enamel hardness, an early sign of enamel damage, while Plus White showed a small increase in hardness. The three whitening oral rinses on the South African market do not damage the tooth enamel significantly when used as recommended by the manufacturers. However, extending the contact period and increasing the frequency of application might lead to damage of enamel.

Bayesian characterization of micro-perforated panels and multi-layer absorbers

NASA Astrophysics Data System (ADS)

Schmitt, Andrew Alexander Joseph

First described by the late acoustician Dah-You Maa, micro-perforated panel (MPP) absorbers produce extremely high acoustic absorption coefficients. This is done without the use of conventional fibrous or porous materials that are often used in acoustic treatments, meaning MPP absorbers are capable of being implemented and withstanding critical situations where traditional absorbers do not suffice. The absorption function of a micro-perforated panel yields high yet relatively narrow results at certain frequencies, although wide-band absorption can be designed by stacking multiple MPP absorbers comprised of different characteristic parameters. Using Bayesian analysis, the physical properties of panel thickness, pore diameter, perforation ratio, and air depth are estimated inversely from experimental data of acoustic absorption, based on theoretical models for design of micro-perforated panels. Furthermore, this analysis helps to understand the interdependence and uncertainties of the parameters and how each affects the performance of the panel. Various micro-perforated panels are manufactured and tested in single- and double-layer absorber constructions.

Fabrication of micro/nano optical fiber by mechano-electrospinning

NASA Astrophysics Data System (ADS)

Chen, Qinnan; Wu, Dezhi; Yu, Zhe; Mei, Xuecui; Fang, Ke; Sun, Daoheng

2017-10-01

We study a novel fabrication method of micro/nano optical fiber by mechano-electrospinning (MES) direct-written technology. MES process is able to precisely manipulate the position and diameter of the electro-spun micro/nano fiber by adjusting the mechanical drawing force, which through changing the speed of motion stage (substrate). By adjusting the substrate speed, the nozzle-to-substrate distance and the applied voltage, the poly(methyl methacrylate) (PMMA) micro/nano optical fibers (MNOF) with controlled diameter are obtained and the tapered MNOF are fabricated by continuously changing the substrate speed. The transmission characteristics of PMMA micro/nano fiber is experimentally demonstrated, and a PMMA micro/nano fiber based refractive index sensor is designed. Our works shows the new fabrication method of MNOF by MES has the potential in the field of light mode conversion, optical waveguide coupling, refractive index detection and new micro/nano optical fiber components.

Identification of unwanted photoproducts of cosmetic preservatives in personal care products under ultraviolet-light using solid-phase microextraction and micro-matrix solid-phase dispersion.

PubMed

Alvarez-Rivera, Gerardo; Llompart, Maria; Garcia-Jares, Carmen; Lores, Marta

2015-04-17

The photochemical transformation of widely used cosmetic preservatives including benzoates, parabens, BHA, BHT and triclosan has been investigated in this work applying an innovative double-approach strategy: identification of transformation products in aqueous photodegradation experiments (UV-light, 254nm), followed by targeted screening analysis of such photoproducts in UV-irradiated cosmetic samples. Solid-phase microextraction (SPME) was applied, using different fiber coatings, in order to widen the range of detectable photoproducts in water, whereas UV-irradiated personal care products (PCPs) containing the target preservatives were extracted by micro-matrix solid-phase dispersion (micro-MSPD). Both SPME and micro-MSPD-based methodologies were successfully optimized and validated. Degradation kinetics of parent species, and photoformation of their transformation by-products were monitored by gas chromatography coupled to mass spectrometry (GC-MS). Thirty nine photoproducts were detected in aqueous photodegradation experiments, being tentatively identified based on their mass spectra. Transformation pathways between structurally related by-products, consistent with their kinetic behavior were postulated. The photoformation of unexpected photoproducts such as 2- and 4-hydroxybenzophenones, and 2,8-dichlorodibenzo-p-dioxin in PCPs are reported in this work for the first time. Copyright © 2015 Elsevier B.V. All rights reserved.

Relative biocompatibility of micro-hybrid and nano-hybrid light-activated composite resins.

PubMed

Olabisi Arigbede, Abiodun; Folasade Adeyemi, Bukola; Femi-Akinlosotu, Omowumi

2017-01-01

Background. In vitro studies have revealed a direct association between resin content and cytotoxicity of composite resins; however, implantation studies in this regard are sparse. This study investigates the relationship between filler content of composite resins and biocompatibility. Methods. This research employed twelve 180‒200-gr male Wistar rats, 1 nano-hybrid (Prime-Dent Inc.) and 1 micro-hybrid (Medental Inc.) composite resins containing 74% and 80‒90% filler content, respectively. The samples were assessed on the 2nd, 14th and 90th day of implantation. Four rats were allocated to each day in this experimental study. A section of 1.5mm long cured nano-hybrid and micro-hybrid materials were implanted into the right and left upper and lower limbs of the rats, respectively. Eight samples were generated on each day of observation. Inflammation was graded according to the criteria suggested by Orstavik and Major. Pearson's chi-squared test was employed to determine the relationship between the tissue responses of the two materials. Statistical significance was set at P < 0.05. Results . The average grade of inflammation for the nano-hybrid on the 2nd day of implantation was 3.3. The micro-hybrid resin had a score of 3.0 for cellular inflammation. On the 14th day, the micro-hybrid resin also exhibited a lower average grade for cellular inflammation. On the 90th day, the micro-hybrid resin had a higher grade of inflammation (0.9) compared to 0.3 recorded for nano-hybrid. The composite resins with higher filler content elicited a significantly lower grade of inflammation irrespective of the duration (χ=20.000, df=8, P=0.010) while the composite resins with lower filler content elicited a significantly lower inflammatory response on the 90th day (χ=4.000, df=1, P=0.046). Conclusion. The composite resins with higher filler content generally elicited significantly lower grades of inflammation, and the composite resins with lower filler content exhibited

Relative biocompatibility of micro-hybrid and nano-hybrid light-activated composite resins

PubMed Central

Olabisi Arigbede, Abiodun; Folasade Adeyemi, Bukola; Femi-Akinlosotu, Omowumi

2017-01-01

Background. In vitro studies have revealed a direct association between resin content and cytotoxicity of composite resins; however, implantation studies in this regard are sparse. This study investigates the relationship between filler content of composite resins and biocompatibility. Methods. This research employed twelve 180‒200-gr male Wistar rats, 1 nano-hybrid (Prime-Dent Inc.) and 1 micro-hybrid (Medental Inc.) composite resins containing 74% and 80‒90% filler content, respectively. The samples were assessed on the 2nd, 14th and 90th day of implantation. Four rats were allocated to each day in this experimental study. A section of 1.5mm long cured nano-hybrid and micro-hybrid materials were implanted into the right and left upper and lower limbs of the rats, respectively. Eight samples were generated on each day of observation. Inflammation was graded according to the criteria suggested by Orstavik and Major. Pearson’s chi-squared test was employed to determine the relationship between the tissue responses of the two materials. Statistical significance was set at P < 0.05. Results. The average grade of inflammation for the nano-hybrid on the 2nd day of implantation was 3.3. The micro-hybrid resin had a score of 3.0 for cellular inflammation. On the 14th day, the micro-hybrid resin also exhibited a lower average grade for cellular inflammation. On the 90th day, the micro-hybrid resin had a higher grade of inflammation (0.9) compared to 0.3 recorded for nano-hybrid. The composite resins with higher filler content elicited a significantly lower grade of inflammation irrespective of the duration (χ=20.000, df=8, P=0.010) while the composite resins with lower filler content elicited a significantly lower inflammatory response on the 90th day (χ=4.000, df=1, P=0.046). Conclusion. The composite resins with higher filler content generally elicited significantly lower grades of inflammation, and the composite resins with lower filler content exhibited

A study on the compatibility between one-bottle dentin adhesives and composite resins using micro-shear bond strength.

PubMed

Song, Minju; Shin, Yooseok; Park, Jeong-Won; Roh, Byoung-Duck

2015-02-01

This study was performed to determine whether the combined use of one-bottle self-etch adhesives and composite resins from same manufacturers have better bond strengths than combinations of adhesive and resins from different manufacturers. 25 experimental micro-shear bond test groups were made from combinations of five dentin adhesives and five composite resins with extracted human molars stored in saline for 24 hr. Testing was performed using the wire-loop method and a universal testing machine. Bond strength data was statistically analyzed using two way analysis of variance (ANOVA) and Tukey's post hoc test. Two way ANOVA revealed significant differences for the factors of dentin adhesives and composite resins, and significant interaction effect (p < 0.001). All combinations with Xeno V (Dentsply De Trey) and Clearfil S(3) Bond (Kuraray Dental) adhesives showed no significant differences in micro-shear bond strength, but other adhesives showed significant differences depending on the composite resin (p < 0.05). Contrary to the other adhesives, Xeno V and BondForce (Tokuyama Dental) had higher bond strengths with the same manufacturer's composite resin than other manufacturer's composite resin. Not all combinations of adhesive and composite resin by same manufacturers failed to show significantly higher bond strengths than mixed manufacturer combinations.

Varactor with integrated micro-discharge source

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

Elizondo-Decanini, Juan M.; Manginell, Ronald P.; Moorman, Matthew W.

2016-10-18

An apparatus that includes a varactor element and an integrated micro-discharge source is disclosed herein. In a general embodiment, the apparatus includes at least one np junction and at least one voltage source that is configured to apply voltage across the np junction. The apparatus further includes an aperture that extends through the np junction. When the voltage is applied across the np junction, gas in the aperture is ionized, forming a plasma, in turn causing a micro-discharge (of light, charge particles, and space charge) to occur. The light (charge particles, and space charge) impinges upon the surface of themore » np junction exposed in the aperture, thereby altering capacitance of the np junction. When used within an oscillator circuit, the effect of the plasma on the np-junction extends the capacitance changes of the np-junction and extends the oscillator frequency range in ways not possible by a conventional voltage controlled oscillator (VCO).« less

Fixture Design for Motion Picture and Theatrical Lighting

NASA Astrophysics Data System (ADS)

Dandridge, Susan

1987-02-01

I am the Marketing Manager for a fairly good-sized company in a very small industry which is dependent on the efforts of the kind of people attending this conference. Strand Lighting and other companies like mine supply the lighting needs of the entertainment industry. We listen to people like Dan Flannery and Bran Ferrren as well as thousands of other creative, artistic designers, manufacturing the tools they need to bring you everything from Hamlet to Dynasty, from Masterpiece Theatre to The Price is Right. We design and manufacture dimmers, computerized control equipment for the dimmers, and lighting fixtures.It it the issue of lighting fixtures for our industry that brings me here today. The total yearly volume of the entire entertainment lighting industry is estimated at only $70 million. Compare that to the billions of the defense or medical industries.

Micro sculpting technology using DPSSL

NASA Astrophysics Data System (ADS)

Chang, Won-Seok; Shin, Bosung; Kim, Jae-gu; Whang, Kyung-Hyun

2003-11-01

Multiple pulse laser ablation of polymer is performed with DPSS (Diode Pumped Solid State) 3rd harmonic Nd:YVO4 laser (355 nm) in order to fabricate three-dimensional micro components. Here we considered mechanistic aspects of the interaction between UV laser and polymer to obtain optimum process conditions for maskless photomachining using DPSSL. The photo-physical and photochemical parameters such as laser wavelength and optical characteristics of polymers are investigated by experiments to reduce plume effect, which induce the re-deposited debris on the surface of substrate. In this study, LDST (laser direct sculpting technique) are developed to gain various three-dimensional shape with size less than 500 micrometer. Main process sequences are from rapid prototyping technology such as CAD/CAM modeling of products, machining path generation, layer-by-layer machining, and so on. This method can be applied to manufacture the prototype of micro device and the polymer mould for mass production without expensive mask fabrication.

Laser-Printed In-Plane Micro-Supercapacitors: From Symmetric to Asymmetric Structure.

PubMed

Huang, Gui-Wen; Li, Na; Du, Yi; Feng, Qing-Ping; Xiao, Hong-Mei; Wu, Xing-Hua; Fu, Shao-Yun

2018-01-10

Here, we propose and demonstrate a complete solution for efficiently fabricating in-plane micro-supercapacitors (MSCs) from a symmetric to asymmetric structure. By using an original laser printing process, symmetric MSC with reduced graphene oxide (rGO)/silver nanowire (Ag-NW) hybrid electrodes was facilely fabricated and a high areal capacitance of 5.5 mF cm -2 was achieved, which reaches the best reports on graphene-based MSCs. More importantly, a "print-and-fold" method has been creatively proposed that enabled the rapid manufacturing of asymmetric in-plane MSCs beyond the traditional cumbersome technologies. α-Ni(OH) 2 particles with high tapping density were successfully synthesized and employed as the pseudocapacitive material. Consequently, an improved supply voltage of 1.5 V was obtained and an areal capacitance as high as 8.6 mF cm -2 has been realized. Moreover, a demonstration of a miniaturized MSC pack was performed by multiply-folding the serial Ag-NW-connected MSC units. As a result, a compact MSC pack with a high supply voltage of 3 V was obtained, which can be utilized to power a light-emitting diode light. These presented technologies may pave the way for the efficiently producing high performance in-plane MSCs, meanwhile offering a solution for the achievement of practical power supply packs integrated in limited spaces.

Biomarkers in Immunoglobulin Light Chain Amyloidosis.

PubMed

Kufová, Z; Sevcikova, T; Growkova, K; Vojta, P; Filipová, J; Adam, Z; Pour, L; Penka, M; Rysava, R; Němec, P; Brozova, L; Vychytilova, P; Jurczyszyn, A; Grosicki, S; Barchnicka, A; Hajdúch, M; Simicek, M; Hájek, R

2017-01-01

Immunoglobulin light chain amyloidosis (AL amyloidosis - ALA) is a monoclonal gammopathy characterized by presence of aberrant plasma cells producing amyloidogenic immunoglobulin light chains. This leads to formation of amyloid fibrils in various organs and tissues, mainly in heart and kidney, and causes their dysfunction. As amyloid depositing in target organs is irreversible, there is a big effort to identify biomarker that could help to distinguish ALA from other monoclonal gammopathies in the early stages of disease, when amyloid deposits are not fatal yet. High throughput technologies bring new opportunities to modern cancer research as they enable to study disease within its complexity. Sophisticated methods such as next generation sequencing, gene expression profiling and circulating microRNA profiling are new approaches to study aberrant plasma cells from patients with light chain amyloidosis and related diseases. While generally known mutation in multiple myeloma patients (KRAS, NRAS, MYC, TP53) were not found in ALA, number of mutated genes is comparable. Transcriptome of ALA patients proves to be more similar to monoclonal gammopathy of undetermined significance patients, moreover level of circulating microRNA, that are known to correlate with heart damage, is increased in ALA patients, where heart damage in ALA typical symptom.Key words: amyloidosis - plasma cell - genome - transcriptome - microRNA.

Optimization of a micro-scale, high throughput process development tool and the demonstration of comparable process performance and product quality with biopharmaceutical manufacturing processes.

PubMed

Evans, Steven T; Stewart, Kevin D; Afdahl, Chris; Patel, Rohan; Newell, Kelcy J

2017-07-14

In this paper, we discuss the optimization and implementation of a high throughput process development (HTPD) tool that utilizes commercially available micro-liter sized column technology for the purification of multiple clinically significant monoclonal antibodies. Chromatographic profiles generated using this optimized tool are shown to overlay with comparable profiles from the conventional bench-scale and clinical manufacturing scale. Further, all product quality attributes measured are comparable across scales for the mAb purifications. In addition to supporting chromatography process development efforts (e.g., optimization screening), comparable product quality results at all scales makes this tool is an appropriate scale model to enable purification and product quality comparisons of HTPD bioreactors conditions. The ability to perform up to 8 chromatography purifications in parallel with reduced material requirements per run creates opportunities for gathering more process knowledge in less time. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Micro-structure and Mechanical Properties of Nano-TiC Reinforced Inconel 625 Deposited using LAAM

NASA Astrophysics Data System (ADS)

Bi, G.; Sun, C. N.; Nai, M. L.; Wei, J.

In this paper, deposition of Ni-base Inconel 625 mixed with nano-TiC powders using laser aided additive manufacturing (LAAM) was studied. Micro-structure and mechanical properties were intensively investigated. The results showed that nano-size TiC distributed uniformly throughout the Ni- matrix. Inconel 625 can be reinforced by the strengthened grain boundaries with nano-size TiC. Improved micro-hardness and tensile properties were observed.

Graphene-based in-plane micro-supercapacitors with high power and energy densities

PubMed Central

Wu, Zhong–Shuai; Parvez, Khaled; Feng, Xinliang; Müllen, Klaus

2013-01-01

Micro-supercapacitors are important on-chip micro-power sources for miniaturized electronic devices. Although the performance of micro-supercapacitors has been significantly advanced by fabricating nanostructured materials, developing thin-film manufacture technologies and device architectures, their power or energy densities remain far from those of electrolytic capacitors or lithium thin-film batteries. Here we demonstrate graphene-based in-plane interdigital micro-supercapacitors on arbitrary substrates. The resulting micro-supercapacitors deliver an area capacitance of 80.7 μF cm−2 and a stack capacitance of 17.9 F cm−3. Further, they show a power density of 495 W cm−3 that is higher than electrolytic capacitors, and an energy density of 2.5 mWh cm−3 that is comparable to lithium thin-film batteries, in association with superior cycling stability. Such microdevices allow for operations at ultrahigh rate up to 1,000 V s−1, three orders of magnitude higher than that of conventional supercapacitors. Micro-supercapacitors with an in-plane geometry have great promise for numerous miniaturized or flexible electronic applications. PMID:24042088

Graphene-based in-plane micro-supercapacitors with high power and energy densities.

PubMed

Wu, Zhong-Shuai; Parvez, Khaled; Feng, Xinliang; Müllen, Klaus

2013-01-01

Micro-supercapacitors are important on-chip micro-power sources for miniaturized electronic devices. Although the performance of micro-supercapacitors has been significantly advanced by fabricating nanostructured materials, developing thin-film manufacture technologies and device architectures, their power or energy densities remain far from those of electrolytic capacitors or lithium thin-film batteries. Here we demonstrate graphene-based in-plane interdigital micro-supercapacitors on arbitrary substrates. The resulting micro-supercapacitors deliver an area capacitance of 80.7 μF cm⁻² and a stack capacitance of 17.9 F cm⁻³. Further, they show a power density of 495 W cm⁻³ that is higher than electrolytic capacitors, and an energy density of 2.5 mWh cm⁻³ that is comparable to lithium thin-film batteries, in association with superior cycling stability. Such microdevices allow for operations at ultrahigh rate up to 1,000 V s⁻¹, three orders of magnitude higher than that of conventional supercapacitors. Micro-supercapacitors with an in-plane geometry have great promise for numerous miniaturized or flexible electronic applications.

[The optimizing design and experiment for a MOEMS micro-mirror spectrometer].

PubMed

Mo, Xiang-xia; Wen, Zhi-yu; Zhang, Zhi-hai; Guo, Yuan-jun

2011-12-01

A MOEMS micro-mirror spectrometer, which uses micro-mirror as a light switch so that spectrum can be detected by a single detector, has the advantages of transforming DC into AC, applying Hadamard transform optics without additional template, high pixel resolution and low cost. In this spectrometer, the vital problem is the conflict between the scales of slit and the light intensity. Hence, in order to improve the resolution of this spectrometer, the present paper gives the analysis of the new effects caused by micro structure, and optimal values of the key factors. Firstly, the effects of diffraction limitation, spatial sample rate and curved slit image on the resolution of the spectrum were proposed. Then, the results were simulated; the key values were tested on the micro mirror spectrometer. Finally, taking all these three effects into account, this micro system was optimized. With a scale of 70 mm x 130 mm, decreasing the height of the image at the plane of micro mirror can not diminish the influence of curved slit image in the spectrum; under the demand of spatial sample rate, the resolution must be twice over the pixel resolution; only if the width of the slit is 1.818 microm and the pixel resolution is 2.2786 microm can the spectrometer have the best performance.

MicroRNA408 Is Critical for the HY5-SPL7 Gene Network That Mediates the Coordinated Response to Light and Copper[C][W

PubMed Central

Zhang, Huiyong; Zhao, Xin; Li, Jigang; Cai, Huaqing; Deng, Xing Wang; Li, Lei

2014-01-01

Light and copper are important environmental determinants of plant growth and development. Despite the wealth of knowledge on both light and copper signaling, the molecular mechanisms that integrate the two pathways remain poorly understood. Here, we use Arabidopsis thaliana to demonstrate an interaction between SQUAMOSA PROMOTER BINDING PROTEIN-LIKE7 (SPL7) and ELONGATED HYPOCOTYL5 (HY5), which mediate copper and light signaling, respectively. Through whole-genome chromatin immunoprecipitation and RNA sequencing analyses, we elucidated the SPL7 regulon and compared it with that of HY5. We found that the two transcription factors coregulate many genes, including those involved in anthocyanin accumulation and photosynthesis. Moreover, SPL7 and HY5 act coordinately to transcriptionally regulate MIR408, which results in differential expression of microRNA408 (miR408) and its target genes in response to changing light and copper conditions. We demonstrate that this regulation is tied to copper allocation to the chloroplast and plastocyanin levels. Finally, we found that constitutively activated miR408 rescues the distinct developmental defects of the hy5, spl7, and hy5 spl7 mutants. These findings revealed the existence of crosstalk between light and copper, mediated by a HY5-SPL7 network. Furthermore, integration of transcriptional and posttranscriptional regulation is critical for governing proper metabolism and development in response to combined copper and light signaling. PMID:25516599

Silicon micromachined broad band light source

NASA Technical Reports Server (NTRS)

George, Thomas (Inventor); Jones, Eric (Inventor); Tuma, Margaret L. (Inventor); Eastwood, Michael (Inventor); Hansler, Richard (Inventor)

2004-01-01

A micro electromechanical system (MEMS) broad band incandescent light source includes three layers: a top transmission window layer; a middle filament mount layer; and a bottom reflector layer. A tungsten filament with a spiral geometry is positioned over a hole in the middle layer. A portion of the broad band light from the heated filament is reflective off the bottom layer. Light from the filament and the reflected light of the filament are transmitted through the transmission window. The light source may operate at temperatures of 2500 K or above. The light source may be incorporated into an on board calibrator (OBC) for a spectrometer.

Chip-based three-dimensional cell culture in perfused micro-bioreactors.

PubMed

Gottwald, Eric; Lahni, Brigitte; Thiele, David; Giselbrecht, Stefan; Welle, Alexander; Weibezahn, Karl-Friedrich

2008-05-21

We have developed a chip-based cell culture system for the three-dimensional cultivation of cells. The chip is typically manufactured from non-biodegradable polymers, e.g., polycarbonate or polymethyl methacrylate by micro injection molding, micro hot embossing or micro thermo-forming. But, it can also be manufactured from bio-degradable polymers. Its overall dimensions are 0.7 1 x 20 x 20 x 0.7 1 mm (h x w x l). The main features of the chips used are either a grid of up to 1156 cubic micro-containers (cf-chip) each the size of 120-300 x 300 x 300 micron (h x w x l) or round recesses with diameters of 300 micron and a depth of 300 micron (r-chip). The scaffold can house 10 Mio. cells in a three-dimensional configuration. For an optimal nutrient and gas supply, the chip is inserted in a bioreactor housing. The bioreactor is part of a closed sterile circulation loop that, in the simplest configuration, is additionally comprised of a roller pump and a medium reservoir with a gas supply. The bioreactor can be run in perfusion, superfusion, or even a mixed operation mode. We have successfully cultivated cell lines as well as primary cells over periods of several weeks. For rat primary liver cells we could show a preservation of organotypic functions for more than 2 weeks. For hepatocellular carcinoma cell lines we could show the induction of liver specific genes not or only slightly expressed in standard monolayer culture. The system might also be useful as a stem cell cultivation system since first differentiation experiments with stem cell lines were promising.

Design method of LED rear fog lamp based on freeform micro-surface reflectors

NASA Astrophysics Data System (ADS)

Yu, Jindong; Wu, Heng

2017-11-01

We propose a practical method for the design of a light-emitting diode (LED) rear fog lamp based on freeform micro-surface reflectors. The lamp consists of nine LEDs and each of them has a freeform micro-surface reflector correspondingly. The micro-surface reflector design includes three steps. An initial freeform reflector is first built based on the light energy maps. The micro-surface reflector is then constructed on the bias of the initial one. Finally, a two-step method is designed to optimize the micro-surface reflector. With the proposed method, a module is designed and LCW DURIS E5 LED source whose emitting surface is 5.7 mm × 3.0 mm is adopted for simulation. A prototype is also assembled and fabricated to verify the real performance. Both the simulation and experimental results demonstrate that the luminous intensity distribution can well fulfill the requirements of ECE No.38 regulation. Furthermore, more than 79% energy can be saved when compared with the rear fog lamps using conventional sources.

Good Manufacturing Practices (GMP) manufacturing of advanced therapy medicinal products: a novel tailored model for optimizing performance and estimating costs.

PubMed

Abou-El-Enein, Mohamed; Römhild, Andy; Kaiser, Daniel; Beier, Carola; Bauer, Gerhard; Volk, Hans-Dieter; Reinke, Petra

2013-03-01

Advanced therapy medicinal products (ATMP) have gained considerable attention in academia due to their therapeutic potential. Good Manufacturing Practice (GMP) principles ensure the quality and sterility of manufacturing these products. We developed a model for estimating the manufacturing costs of cell therapy products and optimizing the performance of academic GMP-facilities. The "Clean-Room Technology Assessment Technique" (CTAT) was tested prospectively in the GMP facility of BCRT, Berlin, Germany, then retrospectively in the GMP facility of the University of California-Davis, California, USA. CTAT is a two-level model: level one identifies operational (core) processes and measures their fixed costs; level two identifies production (supporting) processes and measures their variable costs. The model comprises several tools to measure and optimize performance of these processes. Manufacturing costs were itemized using adjusted micro-costing system. CTAT identified GMP activities with strong correlation to the manufacturing process of cell-based products. Building best practice standards allowed for performance improvement and elimination of human errors. The model also demonstrated the unidirectional dependencies that may exist among the core GMP activities. When compared to traditional business models, the CTAT assessment resulted in a more accurate allocation of annual expenses. The estimated expenses were used to set a fee structure for both GMP facilities. A mathematical equation was also developed to provide the final product cost. CTAT can be a useful tool in estimating accurate costs for the ATMPs manufactured in an optimized GMP process. These estimates are useful when analyzing the cost-effectiveness of these novel interventions. Copyright © 2013 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

PREFACE: 1st European Conference on Gas Micro Flows (GasMems 2012)

NASA Astrophysics Data System (ADS)

Frijns, Arjan; Valougeorgis, Dimitris; Colin, Stéphane; Baldas, Lucien

2012-05-01

The aim of the 1st European Conference on Gas Micro Flows is to advance research in Europe and worldwide in the field of gas micro flows as well as to improve global fundamental knowledge and to enable technological applications. Gas flows in microsystems are of great importance and touch almost every industrial field (e.g. fluidic microactuators for active control of aerodynamic flows, vacuum generators for extracting biological samples, mass flow and temperature micro-sensors, pressure gauges, micro heat-exchangers for the cooling of electronic components or for chemical applications, and micro gas analyzers or separators). The main characteristic of gas microflows is their rarefaction, which for device design often requires modelling and simulation both by continuous and molecular approaches. In such flows various non-equilibrium transport phenomena appear, while the role played by the interaction between the gas and the solid device surfaces becomes essential. The proposed models of boundary conditions often need an empirical adjustment strongly dependent on the micro manufacturing technique. The 1st European Conference on Gas Micro Flows is organized under the umbrella of the recently established GASMEMS network (www.gasmems.eu/) consisting of 13 participants and six associate members. The main objectives of the network are to structure research and train researchers in the fields of micro gas dynamics, measurement techniques for gaseous flows in micro experimental setups, microstructure design and micro manufacturing with applications in lab and industry. The conference takes place on June 6-8 2012, at the Skiathos Palace Hotel, on the beautiful island of Skiathos, Greece. The conference has received funding from the European Community's Seventh Framework Programme FP7/2007-2013 under grant agreement ITN GASMEMS no. 215504. It owes its success to many people. We would like to acknowledge the support of all members of the Scientific Committee and of all

Hybrid integrated single-wavelength laser with silicon micro-ring reflector

NASA Astrophysics Data System (ADS)

Ren, Min; Pu, Jing; Krishnamurthy, Vivek; Xu, Zhengji; Lee, Chee-Wei; Li, Dongdong; Gonzaga, Leonard; Toh, Yeow T.; Tjiptoharsono, Febi; Wang, Qian

2018-02-01

A hybrid integrated single-wavelength laser with silicon micro-ring reflector is demonstrated theoretically and experimentally. It consists of a heterogeneously integrated III-V section for optical gain, an adiabatic taper for light coupling, and a silicon micro-ring reflector for both wavelength selection and light reflection. Heterogeneous integration processes for multiple III-V chips bonded to an 8-inch Si wafer have been developed, which is promising for massive production of hybrid lasers on Si. The III-V layer is introduced on top of a 220-nm thick SOI layer through low-temperature wafer-boning technology. The optical coupling efficiency of >85% between III-V and Si waveguide has been achieved. The silicon micro-ring reflector, as the key element of the hybrid laser, is studied, with its maximized reflectivity of 85.6% demonstrated experimentally. The compact single-wavelength laser enables fully monolithic integration on silicon wafer for optical communication and optical sensing application.

A review of the promises and challenges of micro-concentrator photovoltaics

NASA Astrophysics Data System (ADS)

Domínguez, César; Jost, Norman; Askins, Steve; Victoria, Marta; Antón, Ignacio

2017-09-01

Micro concentrator photovoltaics (micro-CPV) is an unconventional approach for developing high-efficiency low-cost PV systems. The micrifying of cells and optics brings about an increase of efficiency with respect to classical CPV, at the expense of some fundamental challenges at mass production. The large costs linked to miniaturization under conventional serial-assembly processes raise the need for the development of parallel manufacturing technologies. In return, the tiny sizes involved allows exploring unconventional optical architectures or revisiting conventional concepts that were typically discarded because of large material consumption or high bulk absorption at classical CPV sizes.

Mechanical properties of micro-injected HDPE composites

NASA Astrophysics Data System (ADS)

Bongiorno, A.; Pagano, C.; Agnelli, S.; Baldi, F.; Fassi, I.

2016-03-01

Micro-injection moulding is one of the key manufacturing technologies for the mass production of high value polymeric miniaturized-components. However, this process is not just a straightforward down scaling of the conventional injection moulding technique. Indeed, during the micro-injection the polymer melt is forced to flow at high strain rates through very small channels in non-isothermal conditions, and this can lead to complex microstructures and to parts with unexpected performances. In this work, the relationships among the processing conditions, the mechanical properties and the microstructural characteristics of miniaturized specimens obtained by injection moulding were investigated. Two model systems were considered with the same filler content of 15% wt. (HDPE-talc and HDPE-glass beads), representative of two different types of micro-composites: containing lamellar and spherical micro-particles, respectively. The attention was focused on the influence of the filler type and the process conditions on the mechanical behaviour, examined by uniaxial tensile tests and dynamic-mechanical analyses, and on the morphological characteristics of the specimens, examined by microscopy analyses. The results highlight that mechanical response of the miniaturized specimens is significantly affected by both the filler and the process conditions that can have an influence on the polymer microstructure. Lamellar composites showed the best performance due to the orientation of the talc particles during the micro-injection process, while, different morphologies of the skin/core transition region in dependence on the process temperatures were observable.

Monolithic integration of elliptic-symmetry diffractive optical element on silicon-based 45 degrees micro-reflector.

PubMed

Lan, Hsiao-Chin; Hsiao, Hsu-Liang; Chang, Chia-Chi; Hsu, Chih-Hung; Wang, Chih-Ming; Wu, Mount-Learn

2009-11-09

A monolithically integrated micro-optical element consisting of a diffractive optical element (DOE) and a silicon-based 45 degrees micro-reflector is experimentally demonstrated to facilitate the optical alignment of non-coplanar fiber-to-fiber coupling. The slanted 45 degrees reflector with a depth of 216 microm is fabricated on a (100) silicon wafer by anisotropic wet etching. The DOE with a diameter of 174.2 microm and a focal length of 150 microm is formed by means of dry etching. Such a compact device is suitable for the optical micro-system to deflect the incident light by 90 degrees and to focus it on the image plane simultaneously. The measured light pattern with a spot size of 15 microm has a good agreement with the simulated result of the elliptic-symmetry DOE with an off-axis design for eliminating the strongly astigmatic aberration. The coupling efficiency is enhanced over 10-folds of the case without a DOE on the 45 degrees micro-reflector. This device would facilitate the optical alignment of non-coplanar light coupling and further miniaturize the volume of microsystem.

Testing of Piezo-Actuated Glass Micro-Membranes by Optical Low-Coherence Reflectometry.

PubMed

Merlo, Sabina; Poma, Paolo; Crisà, Eleonora; Faralli, Dino; Soldo, Marco

2017-02-25

In this work, we have applied optical low-coherence reflectometry (OLCR), implemented with infra-red light propagating in fiberoptic paths, to perform static and dynamic analyses on piezo-actuated glass micro-membranes. The actuator was fabricated by means of thin-film piezoelectric MEMS technology and was employed for modifying the micro-membrane curvature, in view of its application in micro-optic devices, such as variable focus micro-lenses. We are here showing that OLCR incorporating a near-infrared superluminescent light emitting diode as the read-out source is suitable for measuring various parameters such as the micro-membrane optical path-length, the membrane displacement as a function of the applied voltage (yielding the piezo-actuator hysteresis) as well as the resonance curve of the fundamental vibration mode. The use of an optical source with short coherence-time allows performing interferometric measurements without spurious resonance effects due to multiple parallel interfaces of highly planar slabs, furthermore selecting the plane/layer to be monitored. We demonstrate that the same compact and flexible setup can be successfully employed to perform spot optical measurements for static and dynamic characterization of piezo-MEMS in real time.

Testing of Piezo-Actuated Glass Micro-Membranes by Optical Low-Coherence Reflectometry

PubMed Central

Merlo, Sabina; Poma, Paolo; Crisà, Eleonora; Faralli, Dino; Soldo, Marco

2017-01-01

In this work, we have applied optical low-coherence reflectometry (OLCR), implemented with infra-red light propagating in fiberoptic paths, to perform static and dynamic analyses on piezo-actuated glass micro-membranes. The actuator was fabricated by means of thin-film piezoelectric MEMS technology and was employed for modifying the micro-membrane curvature, in view of its application in micro-optic devices, such as variable focus micro-lenses. We are here showing that OLCR incorporating a near-infrared superluminescent light emitting diode as the read-out source is suitable for measuring various parameters such as the micro-membrane optical path-length, the membrane displacement as a function of the applied voltage (yielding the piezo-actuator hysteresis) as well as the resonance curve of the fundamental vibration mode. The use of an optical source with short coherence-time allows performing interferometric measurements without spurious resonance effects due to multiple parallel interfaces of highly planar slabs, furthermore selecting the plane/layer to be monitored. We demonstrate that the same compact and flexible setup can be successfully employed to perform spot optical measurements for static and dynamic characterization of piezo-MEMS in real time. PMID:28245603

Effect of temperature on microbial composition of starter culture for Chinese light aroma style liquor fermentation.

PubMed

Wang, H Y; Xu, Y

2015-01-01

Light aroma style liquor is one of the basic types of Chinese liquor and is produced with a special technique of using a combination of three types of Daqu as starter culture. The succession of incubation temperature, a main operating parameter, and microbial composition in Daqu were investigated during the manufacturing process. The most significant difference in temperature occurred during the middle stage at which the highest and the lowest temperatures were detected in Houhuo (HH) and Qingcha (QC), respectively. It was shown that for the counting data, the population of fungi was identical and that of bacteria was different between three types of Daqu. According to analysis results of microbial community structure using PCR-denaturing gradient gel electrophoresis (PCR-DGGE), lactic acid bacteria were one of the dominant bacterial groups in all of Daqu and fungal diversity in QC was higher than that in HH and Hongxin (HX). The difference in incubation temperature led to the accumulation of different heat-tolerant and heat-sensitive fungi in the completed Daqu. PCA of DGGE profiles revealed that microbial community structure was distinct between three types of Daqu. It was presumed that temperature might play a decisive role in the formation of micro-organism composition in starter cultures. The usage of a combination of three types of Daqu including Qingcha, Hongxin and Houhuo as starter culture is an important characteristic of production technology of Chinese light aroma style liquor. Micro-organisms from the environment naturally inoculated in Daqu are propagated to form the special microbial community under the control of several operating parameters, especially temperature, and finally play various roles in the fermentation process of liquor. An in-depth study of the relationship between incubation temperature and microbiota in Daqu during the manufacturing is fundamental to understand this complicated process and to prepare high-quality starter culture for

Laser polishing of additive manufactured Ti alloys

NASA Astrophysics Data System (ADS)

Ma, C. P.; Guan, Y. C.; Zhou, W.

2017-06-01

Laser-based additive manufacturing has attracted much attention as a promising 3D printing method for metallic components in recent years. However, surface roughness of additive manufactured components has been considered as a challenge to achieve high performance. In this work, we demonstrate the capability of fiber laser in polishing rough surface of additive manufactured Ti-based alloys as Ti-6Al-4V and TC11. Both as-received surface and laser-polished surfaces as well as cross-section subsurfaces were analyzed carefully by White-Light Interference, Confocal Microscope, Focus Ion Beam, Scanning Electron Microscopy, Energy Dispersive Spectrometer, and X-ray Diffraction. Results revealed that as-received Ti-based alloys with surface roughness more than 5 μm could be reduce to less than 1 μm through laser polishing process. Moreover, microstructure, microhardness and wear resistance of laser-polished zone was investigated in order to examine the thermal effect of laser polishing processing on the substrate of additive manufactured Ti alloys. This proof-of-concept process has the potential to effectively improve the surface roughness of additive manufactured metallic alloy by local polishing method without damage to the substrate.

Materials Manufactured from 3D Printed Synthetic Biology Arrays

NASA Technical Reports Server (NTRS)

Gentry, Diana; Micks, Ashley

2013-01-01

Many complex, biologically-derived materials have extremely useful properties (think wood or silk), but are unsuitable for space-related applications due to production, manufacturing, or processing limitations. Large-scale ecosystem-based production, such as raising and harvesting trees for wood, is impractical in a self-contained habitat such as a space station or potential Mars colony. Manufacturing requirements, such as the specialized equipment needed to harvest and process cotton, add too much upmass for current launch technology. Cells in nature are already highly specialized for making complex biological materials on a micro scale. We envision combining these strengths with the recently emergent technologies of synthetic biology and 3D printing to create 3D-structured arrays of cells that are bioengineered to secrete different materials in a specified three-dimensional pattern.

Investigation for Molecular Attraction Impact Between Contacting Surfaces in Micro-Gears

NASA Astrophysics Data System (ADS)

Yang, Ping; Li, Xialong; Zhao, Yanfang; Yang, Haiying; Wang, Shuting; Yang, Jianming

2013-10-01

The aim of this research work is to provide a systematic method to perform molecular attraction impact between contacting surfaces in micro-gear train. This method is established by integrating involute profile analysis and molecular dynamics simulation. A mathematical computation of micro-gear involute is presented based on geometrical properties, Taylor expression and Hamaker assumption. In the meantime, Morse potential function and the cut-off radius are introduced with a molecular dynamics simulation. So a hybrid computational method for the Van Der Waals force between the contacting faces in micro-gear train is developed. An example is illustrated to show the performance of this method. The results show that the change of Van Der Waals force in micro-gear train has a nonlinear characteristic with parameters change such as the modulus of the gear and the tooth number of gear etc. The procedure implies a potential feasibility that we can control the Van Der Waals force by adjusting the manufacturing parameters for gear train design.

Chemical micro-sensor

DOEpatents

Ruggiero, Anthony J.

2005-05-03

An integrated optical capillary electrophoresis system for analyzing an analyte. A modulated optical pump beam impinges on an capillary containing the analyte/buffer solution which is separated by electrophoresis. The thermally-induced change in the index of refraction of light in said electrophoresis capillary is monitored using an integrated micro-interferometer. The interferometer includes a first interferometer arm intersecting the electrophoresis capillary proximate the excitation beam and a second, reference interferometer arm. Changes in index of refraction in the analyte measured by interrogating the interferometer state using white light interferometry and a phase-generated carrier demodulation technique. Background thermo-optical activity in the buffer solution is cancelled by splitting the pump beam and exciting pure buffer solution in a second section of capillary where it crosses the reference arm of the interferometer.

Multi-peaks scattering of light in glasses

NASA Astrophysics Data System (ADS)

Smirnov, V. A.; Vostrikova, L. I.

2018-04-01

Investigations of the multi-peaks scattering of the laser light on the micro-scale susceptibility gratings with small periodicities photo-induced in the various glass materials are presented. The observed pictures of the multi-peaks scattering of light in oxide samples show that the efficiencies of the processes of scattering can vary for the different chemical compositions. Experimental results are in agreement with the proposed theory of light scattering.

Combined optical resolution photoacoustic and fluorescence micro-endoscopy

NASA Astrophysics Data System (ADS)

Shao, Peng; Shi, Wei; Hajireza, Parsin; Zemp, Roger J.

2012-02-01

We present a new micro-endoscopy system combining real-time C-scan optical-resolution photoacoustic micro-endoscopy (OR-PAME), and a high-resolution fluorescence micro-endoscopy system for visualizing fluorescently labeled cellular components and optically absorbing microvasculature simultaneously. With a diode-pumped 532-nm fiber laser, the OR-PAM sub-system is capable of imaging with a resolution of ~ 7μm. The fluorescence sub-system consists of a diode laser with 445 nm-centered emissions as the light source, an objective lens and a CCD camera. Proflavine, a FDA approved drug for human use, is used as the fluorescent contrast agent by topical application. The fluorescence system does not require any mechanical scanning. The scanning laser and the diode laser light source share the same light path within an optical fiber bundle containing 30,000 individual single mode fibers. The absorption of Proflavine at 532 nm is low, which mitigates absorption bleaching of the contrast agent by the photoacoustic excitation source. We demonstrate imaging in live murine models. The system is able to provide cellular morphology with cellular resolution co-registered with the structural and functional information given by OR-PAM. Therefore, the system has the potential to serve as a virtual biopsy technique, helping researchers and clinicians visualize angiogenesis, effects of anti-cancer drugs on both cells and the microcirculation, as well as aid in the study of other diseases.

Northwest Energy Efficient Manufactured Housing Program Specification Development

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

Hewes, Tom; Peeks, Brady

2013-02-01

The DOE research team Building America Partnership for Improved Residential Construction (BA-PIRC), Bonneville Power Administration (BPA), and Northwest Energy Works (NEW), the current Northwest Energy Efficient Manufactured Home Program (NEEM) program administrator, collaborated to research a new specification that would reduce the energy requirements of a NEEM home.This research identified and developed combinations of cost-effective high performance building assemblies and mechanical systems that can readily can be deployed in the manufacturing setting that reduce energy used for space conditioning, water heating and lighting by 50% over the present NEEM specifications.

Radioluminescent lighting technology

NASA Astrophysics Data System (ADS)

The glow-in-the-dark stereotype that characterizes the popular image of nuclear materials is not accidental. When the French scientist, Henri Becquerel, first discovered radioactivity in 1896, he was interested in luminescence. Radioluminescence, the production of light from a mixture of energetic and passive materials, is probably the oldest practical application of the unstable nucleus. Tritium based radioluminescent lighting, in spite of the biologically favorable character of the gaseous tritium isotope, was included in the general tightening of environmental and safety regulations. Tritium light manufacturers would have to meet two fundamental conditions: (1) The benefit clearly outweighed the risk, to the extent that even the perceived risk of a skeptical public would be overcome; and (2) The need was significant enough that the customer/user would be willing and able to afford the cost of regulation that was imposed both in the manufacture, use, and eventual disposal of nuclear materials. In 1981, researchers at Oak Ridge National Laboratory were investigating larger radioluminescent applications using byproduct nuclear material such as krypton-85, as well as tritium. By 1982, it appeared that large source, (100 Curies or more) tritium gas tube, lights might be useful for marking runways and drop zones for military operations and perhaps even special civilian aviation applications. The successful development of this idea depended on making the light bright enough and demonstrating that large gas tube sources could be used and maintained safely in the environment. The basic program goals were achieved. This is a detailed report of what they have learned, proven, and discovered.

Heat Transfer Enhancement by Finned Heat Sinks with Micro-structured Roughness

NASA Astrophysics Data System (ADS)

Ventola, L.; Chiavazzo, E.; Calignano, F.; Manfredi, D.; Asinari, P.

2014-04-01

We investigated the benefits of micro-structured roughness on heat transfer performance of heat sinks, cooled by forced air. Heat sinks in aluminum alloy by direct metal laser sintering (DMLS) manufacturing technique were fabricated; values of the average surface roughness Ra from 1 to 25 microns (standard milling leads to roughness around 1 micron) under turbulent regimes (Reynolds number based on heating edge from 3000 to 17000) have been explored. An enhancement of 50% in thermal performances with regards to standard manufacturing was observed. This may open the way for huge boost in the technology of electronic cooling by DMLS.

Stray Light Analysis

NASA Technical Reports Server (NTRS)

1997-01-01

Based on a Small Business Innovation Research contract from the Jet Propulsion Laboratory, TracePro is state-of-the-art interactive software created by Lambda Research Corporation to detect stray light in optical systems. An image can be ruined by incidental light in an optical system. To maintain image excellence from an optical system, stray light must be detected and eliminated. TracePro accounts for absorption, specular reflection and refraction, scattering and aperture diffraction of light. Output from the software consists of spatial irradiance plots and angular radiance plots. Results can be viewed as contour maps or as ray histories in tabular form. TracePro is adept at modeling solids such as lenses, baffles, light pipes, integrating spheres, non-imaging concentrators, and complete illumination systems. The firm's customer base includes Lockheed Martin, Samsung Electronics and other manufacturing, optical, aerospace, and educational companies worldwide.

49 CFR 579.22 - Reporting requirements for manufacturers of 100 or more buses, manufacturers of 500 or more...

Code of Federal Regulations, 2014 CFR

2014-10-01

... train, 11 electrical, 12 exterior lighting, 13 visibility, 14 air bags, 15 seat belts, 16 structure, 17... visibility, 14 air bags, 15 seat belts, 16 structure, 17 latch, 18 vehicle speed control, 19 tires, 20 wheels... manufactured and available with more than one type of service brake system (i.e., hydraulic or air), the...

On-Demand Drug Delivery System Using Micro-organogels with Gold Nanorods

PubMed Central

2016-01-01

In this study, we designed a biocompatible drug carrier: micro-organogels prepared by emulsification using vegetable oils and self-assembled gelator fibers. Flurbiprofen was chosen as a hydrophobic model drug and is classified as a nonsteroidal anti-inflammatory drug. In the absence of NIR light, flurbiprofen encapsulated in micro-organogels with gold nanorods (GNRs) was released slowly, while release was accelerated in the presence of NIR light due to the increase in the temperature surrounding the GNRs that transforms the gels into liquid. These results suggest that our system can be efficiently used as a versatile scaffold for on-demand drug delivery systems. PMID:27994743

Ultra-precise micro-motion stage for optical scanning test

NASA Astrophysics Data System (ADS)

Chen, Wen; Zhang, Jianhuan; Jiang, Nan

2009-05-01

This study aims at the application of optical sensing technology in a 2D flexible hinge test stage. Optical fiber sensor which is manufactured taking advantage of the various unique properties of optical fiber, such as good electric insulation properties, resistance of electromagnetic disturbance, sparkless property and availability in flammable and explosive environment, has lots of good properties, such as high accuracy and wide dynamic range, repeatable, etc. and is applied in 2D flexible hinge stage driven by PZT. Several micro-bending structures are designed utilizing the characteristics of the flexible hinge stage. And through experiments, the optimal micro-bending tooth structure and the scope of displacement sensor trip under this optimal micro-bending tooth structure are derived. These experiments demonstrate that the application of optical fiber displacement sensor in 2D flexible hinge stage driven by PZT substantially broadens the dynamic testing range and improves the sensitivity of this apparatus. Driving accuracy and positioning stability are enhanced as well. [1,2

A CMOS Time-Resolved Fluorescence Lifetime Analysis Micro-System

PubMed Central

Rae, Bruce R.; Muir, Keith R.; Gong, Zheng; McKendry, Jonathan; Girkin, John M.; Gu, Erdan; Renshaw, David; Dawson, Martin D.; Henderson, Robert K.

2009-01-01

We describe a CMOS-based micro-system for time-resolved fluorescence lifetime analysis. It comprises a 16 × 4 array of single-photon avalanche diodes (SPADs) fabricated in 0.35 μm high-voltage CMOS technology with in-pixel time-gated photon counting circuitry and a second device incorporating an 8 × 8 AlInGaN blue micro-pixellated light-emitting diode (micro-LED) array bump-bonded to an equivalent array of LED drivers realized in a standard low-voltage 0.35 μm CMOS technology, capable of producing excitation pulses with a width of 777 ps (FWHM). This system replaces instrumentation based on lasers, photomultiplier tubes, bulk optics and discrete electronics with a PC-based micro-system. Demonstrator lifetime measurements of colloidal quantum dot and Rhodamine samples are presented. PMID:22291564

Circulation (Organs). MicroSIFT Courseware Evaluation.

ERIC Educational Resources Information Center

Northwest Regional Educational Lab., Portland, OR.

THE FOLLOWING IS THE FULL TEXT OF THIS DOCUMENT (Except for the Evaluation Summary Table): PRODUCER: Micro Power and Light Company, Keystone Park, Suite 1108, 13773 N. Central Expressway, Dallas, TX 75243. LOCAL DISTRIBUTORS: Contact producer for list. EVALUATION COMPLETED: Fall 1981. VERSION: Apple II. COST: $29.95. ABILITY LEVEL: Grades 5-12.…

The theoretical simulation on electrostatic distribution of 1st proximity region in proximity focusing low-light-level image intensifier

NASA Astrophysics Data System (ADS)

Zhang, Liandong; Bai, Xiaofeng; Song, De; Fu, Shencheng; Li, Ye; Duanmu, Qingduo

2015-03-01

Low-light-level night vision technology is magnifying low light level signal large enough to be seen by naked eye, which uses the photons - photoelectron as information carrier. Until the micro-channel plate was invented, it has been possibility for the realization of high performance and miniaturization of low-light-level night vision device. The device is double-proximity focusing low-light-level image intensifier which places a micro-channel plate close to photocathode and phosphor screen. The advantages of proximity focusing low-light-level night vision are small size, light weight, small power consumption, no distortion, fast response speed, wide dynamic range and so on. It is placed parallel to each other for Micro-channel plate (both sides of it with metal electrode), the photocathode and the phosphor screen are placed parallel to each other. The voltage is applied between photocathode and the input of micro-channel plate when image intensifier works. The emission electron excited by photo on the photocathode move towards to micro-channel plate under the electric field in 1st proximity focusing region, and then it is multiplied through the micro-channel. The movement locus of emission electrons can be calculated and simulated when the distributions of electrostatic field equipotential lines are determined in the 1st proximity focusing region. Furthermore the resolution of image tube can be determined. However the distributions of electrostatic fields and equipotential lines are complex due to a lot of micro-channel existing in the micro channel plate. This paper simulates electrostatic distribution of 1st proximity region in double-proximity focusing low-light-level image intensifier with the finite element simulation analysis software Ansoft maxwell 3D. The electrostatic field distributions of 1st proximity region are compared when the micro-channel plates' pore size, spacing and inclination angle ranged. We believe that the electron beam movement

Decoupled macro/micro-manipulator for fast and precise assembly operations: design and experiments

NASA Astrophysics Data System (ADS)

Hodac, Agathe; Siegwart, Roland Y.

1999-08-01

This paper presents a high performance single arm robot configuration, based on a macro-manipulator coupled with a micro-manipulator. The system is well suited to fast and precise positioning tasks for repetitive pick and place applications in the manufacturing industry. Firstly, the paper focuses on the design of the micro-manipulator, particularly on the selection of the proper micro-actuator type and location. We show that the micro-manipulator's design with an actuator placed between endpoint and ground and with a flexible suspension system can reduce the dynamic coupling between the macro-manipulator and the micro- manipulator. The overall system performance can then be improved. We describe two different designs of compact and fast micro-manipulators composed of voice coil actuators and a monolithic flexure suspension with notch hinges. Secondly, the paper presents a control strategy that allows both correction of possible misalignments of the end-effector relative to the target and compensation of tip oscillations. The dynamic interaction is analyzed and stability is verified. Finally, experimental results demonstrate significant improvements in acceleration, endpoint accuracy and settling time achieved by the novel configuration of the macro/micro-manipulator.

Manufacturing of microarrays.

PubMed

Petersen, David W; Kawasaki, Ernest S

2007-01-01

DNA microarray technology has become a powerful tool in the arsenal of the molecular biologist. Capitalizing on high precision robotics and the wealth of DNA sequences annotated from the genomes of a large number of organisms, the manufacture of microarrays is now possible for the average academic laboratory with the funds and motivation. Microarray production requires attention to both biological and physical resources, including DNA libraries, robotics, and qualified personnel. While the fabrication of microarrays is a very labor-intensive process, production of quality microarrays individually tailored on a project-by-project basis will help researchers shed light on future scientific questions.

Development of optics with micro-LED arrays for improved opto-electronic neural stimulation

NASA Astrophysics Data System (ADS)

Chaudet, Lionel; Neil, Mark; Degenaar, Patrick; Mehran, Kamyar; Berlinguer-Palmini, Rolando; Corbet, Brian; Maaskant, Pleun; Rogerson, David; Lanigan, Peter; Bamberg, Ernst; Roska, Botond

2013-03-01

The breakthrough discovery of a nanoscale optically gated ion channel protein, Channelrhodopsin 2 (ChR2), and its combination with a genetically expressed ion pump, Halorhodopsin, allowed the direct stimulation and inhibition of individual action potentials with light alone. This work reports developments of ultra-bright elec­ tronically controlled optical array sources with enhanced light gated ion channels and pumps for use in systems to further our understanding of both brain and visual function. This work is undertaken as part of the European project, OptoNeuro. Micro-LED arrays permit spatio-temporal control of neuron stimulation on sub-millisecond timescales. However they are disadvantaged by their broad spatial light emission distribution and low fill factor. We present the design and implementation of a projection and micro-optics system for use with a micro-LED array consisting of a 16x16 matrix of 25 μm diameter micro-LEDs with 150 μm centre-to-centre spacing and an emission spectrum centred at 470 nm overlapping the peak sensitivity of ChR2 and its testing on biological samples. The projection system images the micro-LED array onto micro-optics to improve the fill-factor from ~2% to more than 78% by capturing a larger fraction of the LED emission and directing it correctly to the sample plane. This approach allows low fill factor arrays to be used effectively, which in turn has benefits in terms of thermal management and electrical drive from CMOS backplane electronics. The entire projection system is integrated into a microscope prototype to provide stimulation spots at the same size as the neuron cell body (μ10 pm).

Blood-mimicking delivery in polygonal structure of inner quadrupletip microneedle with valveless micro-pump

NASA Astrophysics Data System (ADS)

Ibrahim, M. D.; Yunos, Y. S.; Rigit, A. R. H.; Mohtadzar, N. A. A.; Watanabe, N.; Sunami, Y.; Rahman, M. R. A.; Wong, L. K.; Mohtar, M. Z.

2017-04-01

This paper presents a titanium quadrupletip micro-needle integrated with a micro-pump with different inner designs, length and diameter of the micro-channels to measure and maximize the velocity flow in the micro-needle as blood delivered into human body. Titanium is used as the material of the micro-needle which are also the common material in manufacturing of micro-needle. The advancement of micro-needle technologies is improved in penetrating human outermost skin, stratum corneum and further to human blood vessels. The micro-needles with channel inner design of circular, square, hexagon, and dodecagon with quadruple tip designs are drawn with inner diameter parameter of 150μm and 100μm with two different channel length which are 10mm and 25mm. The characteristics of blood delivery in geometrically changed inner designs affect the output velocity in microneedle when the micropump is operating. The results showed that, when it is pumped at 0.04m/s, the blood velocity improved by 5.6% than when the pump is increased by 30% of its capacity. This is due to the backflow generated in the micropump.

Chamber study of PCB emissions from caulking materials and light ballasts.

PubMed

Liu, Xiaoyu; Guo, Zhishi; Krebs, Kenneth A; Stinson, Rayford A; Nardin, Joshua A; Pope, Robert H; Roache, Nancy F

2015-10-01

The emissions of polychlorinated biphenyl (PCB) congeners from thirteen caulk samples were tested in a micro-chamber system. Twelve samples were from PCB-contaminated buildings and one was prepared in the laboratory. Nineteen light ballasts collected from buildings that represent 13 different models from five manufacturers were tested in 53-L environmental chambers. The rates of PCB congener emissions from caulking materials and light ballasts were determined. Several factors that may have affected the emission rates were evaluated. The experimentally determined emission factors showed that, for a given PCB congener, there is a linear correlation between the emission factor and the concentration of the PCB congener in the source. Furthermore, the test results showed that an excellent log-linear correlation exists between the normalized emission factor and the vapor pressure (coefficient of determination, r(2)⩾0.8846). The PCB congener emissions from ballasts at or near room temperature were relatively low with or without electrical load. However, the PCB congener emission rates increased significantly as the temperature increased. The results of this research provide new data and models for ranking the primary sources of PCBs and supports the development and refinement of exposure assessment models for PCBs. Published by Elsevier Ltd.

In vitro Evaluation of the Marginal Fit and Internal Adaptation of Zirconia and Lithium Disilicate Single Crowns: Micro-CT Comparison Between Different Manufacturing Procedures.

PubMed

Riccitiello, Francesco; Amato, Massimo; Leone, Renato; Spagnuolo, Gianrico; Sorrentino, Roberto

2018-01-01

Prosthetic precision can be affected by several variables, such as restorative materials, manufacturing procedures, framework design, cementation techniques and aging. Marginal adaptation is critical for long-term longevity and clinical success of dental restorations. Marginal misfit may lead to cement exposure to oral fluids, resulting in microleakage and cement dissolution. As a consequence, marginal discrepancies enhance percolation of bacteria, food and oral debris, potentially causing secondary caries, endodontic inflammation and periodontal disease. The aim of the present in vitro study was to evaluate the marginal and internal adaptation of zirconia and lithium disilicate single crowns, produced with different manufacturing procedures. Forty-five intact human maxillary premolars were prepared for single crowns by means of standardized preparations. All-ceramic crowns were fabricated with either CAD-CAM or heat-pressing procedures (CAD-CAM zirconia, CAD-CAM lithium disilicate, heat-pressed lithium disilicate) and cemented onto the teeth with a universal resin cement. Non-destructive micro-CT scanning was used to achieve the marginal and internal gaps in the coronal and sagittal planes; then, precision of fit measurements were calculated in a dedicated software and the results were statistically analyzed. The heat-pressed lithium disilicate crowns were significantly less accurate at the prosthetic margins (p<0.05) while they performed better at the occlusal surface ( p <0.05). No significant differences were noticed between CAD-CAM zirconia and lithium disilicate crowns ( p >0.05); nevertheless CAD-CAM zirconia copings presented the best marginal fit among the experimental groups. As to the thickness of the cement layer, reduced amounts of luting agent were noticed at the finishing line, whereas a thicker layer was reported at the occlusal level. Within the limitations of the present in vitro investigation, the following conclusions can be drawn: the recorded

Micro Hopping Robots for Rescue Operation. Location of the Distributed Tiny Robots Under the Collapsed Building

DTIC Science & Technology

2008-07-31

any wheels or legs even on small, rough terrain with the help of eccentric mechanical vibration. This tiny robot also has the ability of self...integral part of any robo -rescue operation. Inexpensive micro robots can be manufactured for this purpose and by utilizing numerous micro robots (100s to...designed and developed. This locomotion mechanism functions without any wheels or legs and can move based upon the asymmetrical thrusting and lifting

Efficient 1535 nm light emission from an all-Si-based optical micro-cavity containing Er³⁺ and Yb³⁺ ions.

PubMed

Gallo, I B; Braud, A; Zanatta, A R

2013-11-18

This work reports on the construction and spectroscopic analyses of optical micro-cavities (OMCs) that efficiently emit at ~1535 nm. The emission wavelength matches the third transmission window of commercial optical fibers and the OMCs were entirely based on silicon. The sputtering deposition method was adopted in the preparation of the OMCs, which comprised two Bragg reflectors and one spacer layer made of either Er- or ErYb-doped amorphous silicon nitride. The luminescence signal extracted from the OMCs originated from the 4I(13/2)→<4I(15/2) transition (due to Er3 ions) and its intensity showed to be highly dependent on the presence of Yb3+ ions. According to the results, the Er3+-related light emission was improved by a factor of 48 when combined with Yb3+ ions and inserted in the spacer layer of the OMC. The results also showed the effectiveness of the present experimental approach in producing Si-based light-emitting structures in which the main characteristics are: (a) compatibility with the actual micro-electronics industry, (b) the deposition of optical quality layers with accurate composition control, and (c) no need of uncommon elements-compounds nor extensive thermal treatments. Along with the fundamental characteristics of the OMCs, this work also discusses the impact of the Er3+-Yb3+ ion interaction on the emission intensity as well as the potential of the present findings.

Effect of the irradiance distribution from light curing units on the local micro-hardness of the surface of dental resins.

PubMed

Haenel, Thomas; Hausnerová, Berenika; Steinhaus, Johannes; Price, Richard B T; Sullivan, Braden; Moeginger, Bernhard

2015-02-01

An inhomogeneous irradiance distribution from a light-curing unit (LCU) can locally cause inhomogeneous curing with locally inadequately cured and/or over-cured areas causing e.g. monomer elution or internal shrinkage stresses, and thus reduce the lifetime of dental resin based composite (RBC) restorations. The aim of the study is to determine both the irradiance distribution of two light curing units (LCUs) and its influence on the local mechanical properties of a RBC. Specimens of Arabesk TOP OA2 were irradiated for 5, 20, and 80s using a Bluephase® 20i LCU in the Low mode (666mW/cm(2)), in the Turbo mode (2222mW/cm(2)) and a Celalux® 2 (1264mW/cm(2)). The degree of conversion (DC) was determined with an ATR-FTIR. The Knoop micro-hardness (average of five specimens) was measured on the specimen surface after 24h of dark and dry storage at room temperature. The irradiance distribution affected the hardness distribution across the surface of the specimens. The hardness distribution corresponded well to the inhomogeneous irradiance distributions of the LCU. The highest reaction rates occurred after approximately 2s light exposure. A DC of 40% was reached after 3.6 or 5.7s, depending on the LCU. The inhomogeneous hardness distribution was still evident after 80s of light exposure. The irradiance distribution from a LCU is reflected in the hardness distribution across the surface. Irradiance level of the LCU and light exposure time do not affect the pattern of the hardness distribution--only the hardness level. In areas of low irradiation this may result in inadequate resin polymerization, poor physical properties, and hence premature failure of the restorations as they are usually much smaller than the investigated specimens. It has to be stressed that inhomogeneous does not necessarily mean poor if in all areas of the restoration enough light intensity is introduced to achieve a high degree of cure. Copyright © 2014 Academy of Dental Materials. Published by

Scalable Manufacturing of Metal Micro/Nanowires and Applications by Thermal Fiber Drawing Method

NASA Astrophysics Data System (ADS)

Hwang, Injoo

The objective of this study is to better understand the fundamental principal of the thermal fiber drawing process with metal-core preforms. This would enable us to overcome the fundamental limits of current thermal drawing techniques by tuning material properties of core metals and interactions between core and cladding materials using nanoparticles. Metal micro/nanowires with controlled size, aspect ratio and spatial configurations of core and cladding materials exhibit extraordinary mechanical, thermal, electrical and optical properties. These metal micro/nanowires can be utilized for widespread applications such as: thermoelectric, conductive electrode and plasmonic photonic crystal fibers. Thermal fiber drawing method has emerged as an advanced scalable manufacturing technique for micro/nanowires production due to its unique characteristics that allow mass production of continuous and arbitrary designed wires. It is of tremendous scientific and technical interests to conduct a fundamental study on thermal fiber drawing methods and to break the current limits of the crystalline metal core thermal fiber drawing process. In this study, metal core was fabricated by cold compaction of the Zinc (Zn)-Tungsten Carbide (WC) nanopowders. Our characterizations through scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) showed that WC nanoparticle are uniformly dispersed in Zn matrix. The effects of WC nanoparticles on the mechanical properties and degradation rate in Zn-WC nanocomposites were carefully analyzed by tensile, compressive, hardness, degradation and viscosity tests. Metallic stents are commonly used to expand blood vessels that have been narrowed by plaque buildup (atherosclerosis). Fabrication difficulty and other constrains of metallic stents result in high cost. Zn-WC nanocomposite microwires were controllably drawn for stent struts with a diameter of 200 ?m. Characterizations by the tensile and degradation tests of Zn

Fatigue behavior of porous biomaterials manufactured using selective laser melting.

PubMed

Yavari, S Amin; Wauthle, R; van der Stok, J; Riemslag, A C; Janssen, M; Mulier, M; Kruth, J P; Schrooten, J; Weinans, H; Zadpoor, A A

2013-12-01

Porous titanium alloys are considered promising bone-mimicking biomaterials. Additive manufacturing techniques such as selective laser melting allow for manufacturing of porous titanium structures with a precise design of micro-architecture. The mechanical properties of selective laser melted porous titanium alloys with different designs of micro-architecture have been already studied and are shown to be in the range of mechanical properties of bone. However, the fatigue behavior of this biomaterial is not yet well understood. We studied the fatigue behavior of porous structures made of Ti6Al4V ELI powder using selective laser melting. Four different porous structures were manufactured with porosities between 68 and 84% and the fatigue S-N curves of these four porous structures were determined. The three-stage mechanism of fatigue failure of these porous structures is described and studied in detail. It was found that the absolute S-N curves of these four porous structures are very different. In general, given the same absolute stress level, the fatigue life is much shorter for more porous structures. However, the normalized fatigue S-N curves of these four structures were found to be very similar. A power law was fitted to all data points of the normalized S-N curves. It is shown that the measured data points conform to the fitted power law very well, R(2)=0.94. This power law may therefore help in estimating the fatigue life of porous structures for which no fatigue test data is available. It is also observed that the normalized endurance limit of all tested porous structures (<0.2) is lower than that of corresponding solid material (c.a. 0.4). © 2013.

Interference effects in laser-induced plasma emission from surface-bound metal micro-particles

DOE PAGES

Feigenbaum, Eyal; Malik, Omer; Rubenchik, Alexander M.; ...

2017-04-19

Here, the light-matter interaction of an optical beam and metal micro-particulates at the vicinity of an optical substrate surface is critical to the many fields of applied optics. Examples of impacted fields are laser-induced damage in high power laser systems, sub-wavelength laser machining of transmissive materials, and laser-target interaction in directed energy applications. We present a full-wave-based model that predicts the laser-induced plasma pressure exerted on a substrate surface as a result of light absorption in surface-bound micron-scale metal particles. The model predictions agree with experimental observation of laser-induced shallow pits, formed by plasma emission and etching from surface-bound metalmore » micro-particulates. It provides an explanation for the prototypical side lobes observed along the pit profile, as well as for the dependence of the pit shape on the incident laser and particle parameters. Furthermore, the model highlights the significance of the interference of the incident light in the open cavity geometry formed between the micro-particle and the substrate in the resulting pit shape.« less

Interference effects in laser-induced plasma emission from surface-bound metal micro-particles.

PubMed

Feigenbaum, Eyal; Malik, Omer; Rubenchik, Alexander M; Matthews, Manyalibo J

2017-05-01

The light-matter interaction of an optical beam and metal micro-particulates at the vicinity of an optical substrate surface is critical to the many fields of applied optics. Examples of impacted fields are laser-induced damage in high power laser systems, sub-wavelength laser machining of transmissive materials, and laser-target interaction in directed energy applications. We present a full-wave-based model that predicts the laser-induced plasma pressure exerted on a substrate surface as a result of light absorption in surface-bound micron-scale metal particles. The model predictions agree with experimental observation of laser-induced shallow pits, formed by plasma emission and etching from surface-bound metal micro-particulates. It provides an explanation for the prototypical side lobes observed along the pit profile, as well as for the dependence of the pit shape on the incident laser and particle parameters. Furthermore, the model highlights the significance of the interference of the incident light in the open cavity geometry formed between the micro-particle and the substrate in the resulting pit shape.

Device and nondestructive method to determine subsurface micro-structure in dense materials

DOEpatents

Sun, Jiangang [Westmont, IL

2006-05-09

A method and a device to detect subsurface three-dimensional micro-structure in a sample by illuminating the sample with light of a given polarization and detecting light emanating from the sample that has a different direction of polarization by means of a confocal optical system.

Unit cell-based computer-aided manufacturing system for tissue engineering.

PubMed

Kang, Hyun-Wook; Park, Jeong Hun; Kang, Tae-Yun; Seol, Young-Joon; Cho, Dong-Woo

2012-03-01

Scaffolds play an important role in the regeneration of artificial tissues or organs. A scaffold is a porous structure with a micro-scale inner architecture in the range of several to several hundreds of micrometers. Therefore, computer-aided construction of scaffolds should provide sophisticated functionality for porous structure design and a tool path generation strategy that can achieve micro-scale architecture. In this study, a new unit cell-based computer-aided manufacturing (CAM) system was developed for the automated design and fabrication of a porous structure with micro-scale inner architecture that can be applied to composite tissue regeneration. The CAM system was developed by first defining a data structure for the computing process of a unit cell representing a single pore structure. Next, an algorithm and software were developed and applied to construct porous structures with a single or multiple pore design using solid freeform fabrication technology and a 3D tooth/spine computer-aided design model. We showed that this system is quite feasible for the design and fabrication of a scaffold for tissue engineering.

Enabling In-Theater Processes for Indigenous, Recycled, and Reclaimed Material Manufacturing

DTIC Science & Technology

2015-12-01

compression testing was accomplished on this material alone, as well as infused aluminum foam . The LTS-infused aluminum foam showed an interesting...protection against blast threats. 15. SUBJECT TERMS indigenous manufacturing, concrete alternatives, nondestructive evaluation, metallic foam testing...of Blocks on a FOB: CO2 Supply 11 6.7 Metallic Foam Infiltration with LTS Ceramic 12 6.8 LTS Ceramic Made with Gasified Char 21 6.9 Micro Auto

Amorphous Silica Micro Powder Additive Influence on Tensile Strength of One-Ply Particle Board

NASA Astrophysics Data System (ADS)

Pitukhin, A. V.; Kolesnikov, G. N.; Panov, N. G.; Vasilyev, S. B.

2018-03-01

The methods and results of experimental investigation on the additive influence of amorphous silica micro powder when mixed in the glue for one-ply particle board are presented in the article. Wooden particles of coniferous and hardwood species as well as glue solution based on carbamide-formaldehyde resin were used for boards manufacturing. The amorphous silica micro powder contained particles on the average 8 μm by the size and specific surface 120…400 m2/g was used in experiment. The samples were tested to determine their physical-mechanical properties. It was found that 1 % amorphous silica micro powder additive increases the breaking point of one-ply particle board under tensile stress by 143 %.

Prototyping of ultra micro centrifugal compressor-influence of meridional configuration

NASA Astrophysics Data System (ADS)

Hirano, Toshiyuki; Muto, Tadataka; Tsujita, Hoshio

2011-08-01

In order to investigate the design method for a micro centrifugal compressor, which is the most important component of an ultra micro gas turbine, two types of centrifugal impeller with 2-dimensional blade were designed, manufactured and tested. These impellers have different shapes of hub on the meridional plane with each other. Moreover, these types of impeller were made for the 5 times and the 6 times size of the final target centrifugal impeller with the outer diameter of 4mm in order to assess the similitude for the impellers. The comparison among the performance characteristics of the impellers revealed the influence of the meridional configuration on the performance and the similitude of the compressors.

Microscopic vision modeling method by direct mapping analysis for micro-gripping system with stereo light microscope.

PubMed

Wang, Yuezong; Zhao, Zhizhong; Wang, Junshuai

2016-04-01

We present a novel and high-precision microscopic vision modeling method, which can be used for 3D data reconstruction in micro-gripping system with stereo light microscope. This method consists of four parts: image distortion correction, disparity distortion correction, initial vision model and residual compensation model. First, the method of image distortion correction is proposed. Image data required by image distortion correction comes from stereo images of calibration sample. The geometric features of image distortions can be predicted though the shape deformation of lines constructed by grid points in stereo images. Linear and polynomial fitting methods are applied to correct image distortions. Second, shape deformation features of disparity distribution are discussed. The method of disparity distortion correction is proposed. Polynomial fitting method is applied to correct disparity distortion. Third, a microscopic vision model is derived, which consists of two models, i.e., initial vision model and residual compensation model. We derive initial vision model by the analysis of direct mapping relationship between object and image points. Residual compensation model is derived based on the residual analysis of initial vision model. The results show that with maximum reconstruction distance of 4.1mm in X direction, 2.9mm in Y direction and 2.25mm in Z direction, our model achieves a precision of 0.01mm in X and Y directions and 0.015mm in Z direction. Comparison of our model with traditional pinhole camera model shows that two kinds of models have a similar reconstruction precision of X coordinates. However, traditional pinhole camera model has a lower precision of Y and Z coordinates than our model. The method proposed in this paper is very helpful for the micro-gripping system based on SLM microscopic vision. Copyright © 2016 Elsevier Ltd. All rights reserved.

Soft lithography microlens fabrication and array for enhanced light extraction from organic light emitting diodes (OLEDs)

DOEpatents

Leung, Wai Y.; Park, Joong-Mok; Gan, Zhengqing; Constant, Kristen P.; Shinar, Joseph; Shinar, Ruth; ho, Kai-Ming

2014-06-03

Provided are microlens arrays for use on the substrate of OLEDs to extract more light that is trapped in waveguided modes inside the devices and methods of manufacturing same. Light extraction with microlens arrays is not limited to the light emitting area, but is also efficient in extracting light from the whole microlens patterned area where waveguiding occurs. Large microlens array, compared to the size of the light emitting area, extract more light and result in over 100% enhancement. Such a microlens array is not limited to (O)LEDs of specific emission, configuration, pixel size, or pixel shape. It is suitable for all colors, including white, for microcavity OLEDs, and OLEDs fabricated directly on the (modified) microlens array.

Study of cylindrical optical micro-structure technology used in infrared laser protection

NASA Astrophysics Data System (ADS)

Sun, Yanjun; Liu, Shunrui; Wang, Zhining; Zhao, Yixuan; Wu, Boqi; Leng, Yanbing; Wang, Li

2016-10-01

The paper aimed at the problem that strong absorption in visible wavelengths and equipment or operator injury caused by specular reflection exist in infrared laser protection technology to propose an infrared laser non-specular reflection optical micro-structure formed from optical window surface. It has the function of little effect on visible light transmission and large-angle scattering to 1064nm infrared laser in order to enable laser protection. The paper uses light track method to design double-side micro-cylindrical lens arrays with dislocation construction. Array period T and curvature radius of lens units R should meet the condition:0micro-structure, the simulation results: average transmittance rate of visible light drops 7% ,which has little impact on practical result, and we can make it up by visible wavelengths fabrication antireflection coating; 1064nm infrared laser reflection is about 75%, divergence angle is greater than 30%,which greatly reduces the single-directivity reflection echo energy of laser to achieve the purpose of laser protection.

Theoretical and experimental analysis of AlGaInP micro-LED array with square-circle anode

NASA Astrophysics Data System (ADS)

Tian, Chao; Wang, Weibiao; Liang, Jingqiu; Liang, Zhongzhu; Qin, Yuxin; Lv, Jinguang

2015-04-01

An array of 320 × 240 micro-light-emitting diodes (micro-LEDs) based on an AlGaInP epitaxial wafer and with a unit size of 100 µm×100 µm was designed and fabricated. The optimum width of the isolation groove between adjacent light-emitting units was determined based on a compromise between full isolation of each LED and maximization of the light emitting area, and was found to be 20 µm. The grooves were filled with a mixed Si granule-polyurethane composite medium, because this type of insulating material can reflect part of the emitted light from the sidewall to the window layer in each light-emitting unit, and could thus improve lighting output efficiency. The 10-µm-wide square-circle anode was designed to increase the light emitting area while simultaneously being simple to fabricate. The device current used was in the 0.42-1.06 mA range to guarantee internal quantum efficiency of more than 85%, with a corresponding voltage range of 2-2.3 V. The layered temperature distribution in a single unit was simulated under a drive voltage of 2.2 V, and the maximum device temperature was 341 K. The micro-opto-electro-mechanical systems (MOEMS) technology-based fabrication process, experimental images of the device and device test results are presented here.

Theoretical and experimental analysis of AlGaInP micro-LED array with square-circle anode

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

Tian, Chao; University of Chinese Academy of Sciences, Beijing 100049; Wang, Weibiao, E-mail: wangwbcn@163.com

An array of 320 × 240 micro-light-emitting diodes (micro-LEDs) based on an AlGaInP epitaxial wafer and with a unit size of 100 µm×100 µm was designed and fabricated. The optimum width of the isolation groove between adjacent light-emitting units was determined based on a compromise between full isolation of each LED and maximization of the light emitting area, and was found to be 20 µm. The grooves were filled with a mixed Si granule-polyurethane composite medium, because this type of insulating material can reflect part of the emitted light from the sidewall to the window layer in each light-emitting unit,more » and could thus improve lighting output efficiency. The 10-µm-wide square-circle anode was designed to increase the light emitting area while simultaneously being simple to fabricate. The device current used was in the 0.42–1.06 mA range to guarantee internal quantum efficiency of more than 85%, with a corresponding voltage range of 2–2.3 V. The layered temperature distribution in a single unit was simulated under a drive voltage of 2.2 V, and the maximum device temperature was 341 K. The micro-opto-electro-mechanical systems (MOEMS) technology-based fabrication process, experimental images of the device and device test results are presented here.« less

Introduction to Micro/Nanofabrication

NASA Astrophysics Data System (ADS)

Ziaie, Babak; Baldi, Antonio; Atashbar, Massood

This chapter outlines and discusses important micro- and nanofabrication techniques. We start with the most basic methods borrowed from the integrated circuit (IC) industry, such as thin film deposition, lithography and etching, and then move on to look at MEMS and nanofabrication technologies. We cover a broad range of dimensions, from the micron to the nanometer scale. Although most of the current research is geared towards the nanodomain, a good understanding of top-down methods for fabricating micron-sized objects can aid our understanding of this research. Due to space constraints, we have focused here on the most important technologies; in the microdomain these include surface, bulk and high aspect ratio micromachining; in the nanodomain we concentrate on e-beam lithography, epitaxial growth, template manufacturing and self-assembly. MEMS technology is maturing rapidly, with some new technologies displacing older ones that have proven to be unsuited to manufacture on a commercial scale. However, the jury is still out on methods used in the nanodomain, although it appears that bottom-up methods are the most feasible, and these will have a major impact in a variety of application areas such as biology, medicine, environmental monitoring and nanoelectronics.

Capability of Sputtered Micro-patterned NiTi Thick Films

NASA Astrophysics Data System (ADS)

Bechtold, Christoph; Lima de Miranda, Rodrigo; Quandt, Eckhard

2015-09-01

Today, most NiTi devices are manufactured by a combination of conventional metal fabrication steps, e.g., melting, extrusion, cold working, etc., and are subsequently structured by high accuracy laser cutting. This combination has been proven to be very successful; however, there are several limitations to this fabrication route, e.g., in respect to the fabrication of more complex device designs, device miniaturization or the combination of different materials for the integration of further functionality. These issues have to be addressed in order to develop new devices and applications. The fabrication of micro-patterned films using magnetron sputtering, UV lithography, and wet etching has great potential to overcome limitations of conventional device manufacturing. Due to its fabrication characteristics, this method allows the production of devices with complex designs, high structural accuracy, smooth edge profile, at layer thicknesses up to 75 µm. The aim of this study is to present recent developments in the field of NiTi thin film technology, its advantages and limitations, as well as new possible applications in the medical and in non-medical fields. These developments include among others NiTi scaffold structures covered with NiTi membranes for their potential use as filters, heart valve components or aneurysm treatments, as well as micro-actuators for consumable electronics or automotive applications.

Fringe stabilizers and their application to telecommunication device manufacturing

NASA Astrophysics Data System (ADS)

Odhner, Jefferson E.

2000-10-01

The ability to create stable holographic grating is an important part of the production of many telecommunication products. The stability problem is increased by the need to use ultra-violet light for close fringe spacing and long exposure times on phot-resist - a relatively low sensitivity material. Active fringe locking increases the modulation depth and efficiency of these holographic gratings. A discussion of how fringe lockers work and how they can be incorporated into a manufacturing set-up is followed by results of using fringe lockers in the manufacturing of some telecommunication devices.

A novel optical system design of light field camera

NASA Astrophysics Data System (ADS)

Wang, Ye; Li, Wenhua; Hao, Chenyang

2016-01-01

The structure of main lens - Micro Lens Array (MLA) - imaging sensor is usually adopted in optical system of light field camera, and the MLA is the most important part in the optical system, which has the function of collecting and recording the amplitude and phase information of the field light. In this paper, a novel optical system structure is proposed. The novel optical system is based on the 4f optical structure, and the micro-aperture array (MAA) is used to instead of the MLA for realizing the information acquisition of the 4D light field. We analyze the principle that the novel optical system could realize the information acquisition of the light field. At the same time, a simple MAA, line grating optical system, is designed by ZEMAX software in this paper. The novel optical system is simulated by a line grating optical system, and multiple images are obtained in the image plane. The imaging quality of the novel optical system is analyzed.

Si light-emitting device in integrated photonic CMOS ICs

NASA Astrophysics Data System (ADS)

Xu, Kaikai; Snyman, Lukas W.; Aharoni, Herzl

2017-07-01

The motivation for integrated Si optoelectronics is the creation of low-cost photonics for mass-market applications. Especially, the growing demand for sensitive biochemical sensors in the environmental control or medicine leads to the development of integrated high resolution sensors. Here CMOS-compatible Si light-emitting device structures are presented for investigating the effect of various depletion layer profiles and defect engineering on the photonic transition in the 1.4-2.8 eV. A novel Si device is proposed to realize both a two-terminal Si-diode light-emitting device and a three-terminal Si gate-controlled diode light-emitting device in the same device structure. In addition to the spectral analysis, differences between two-terminal and three-terminal devices are discussed, showing the light emission efficiency change. The proposed Si optical source may find potential applications in micro-photonic systems and micro-optoelectro-mechanical systems (MOEMS) in CMOS integrated circuitry.

A hybrid life cycle inventory of nano-scale semiconductor manufacturing.

PubMed

Krishnan, Nikhil; Boyd, Sarah; Somani, Ajay; Raoux, Sebastien; Clark, Daniel; Dornfeld, David

2008-04-15

The manufacturing of modern semiconductor devices involves a complex set of nanoscale fabrication processes that are energy and resource intensive, and generate significant waste. It is important to understand and reduce the environmental impacts of semiconductor manufacturing because these devices are ubiquitous components in electronics. Furthermore, the fabrication processes used in the semiconductor industry are finding increasing application in other products, such as microelectromechanical systems (MEMS), flat panel displays, and photovoltaics. In this work we develop a library of typical gate-to-gate materials and energy requirements, as well as emissions associated with a complete set of fabrication process models used in manufacturing a modern microprocessor. In addition, we evaluate upstream energy requirements associated with chemicals and materials using both existing process life cycle assessment (LCA) databases and an economic input-output (EIO) model. The result is a comprehensive data set and methodology that may be used to estimate and improve the environmental performance of a broad range of electronics and other emerging applications that involve nano and micro fabrication.

Tracking Control and System Development for Laser-Driven Micro-Vehicles

NASA Astrophysics Data System (ADS)

Kajiwara, Itsuro; Hoshino, Kentaro; Hara, Shinji; Shiokata, Daisuke; Yabe, Takashi

The purpose of this paper is to design a control system for an integrated laser propulsion/tracking system to achieve continuous motion and control of laser-driven micro-vehicles. Laser propulsion is significant in achieving miniature and light micro-vehicles. A laser-driven micro-airplane has been studied using a paper airplane and YAG laser, resulting in successful gliding of the airplane. High-performance laser tracking control is required to achieve continuous flight. This paper presents a control design strategy based on the generalized Kalman-Yakubovic-Popov lemma to achieve this requirement. Experiments have been carried out to evaluate the performance of the integrated laser propulsion/tracking system.

Light robotics: aiming towards all-optical nano-robotics

NASA Astrophysics Data System (ADS)

Glückstad, Jesper; Palima, Darwin; Banas, Andrew

2017-04-01

Light Robotics is a new field of research where ingredients from photonics, nanotechnology and biotechnology are put together in new ways to realize light-driven robotics at the smallest scales to solve major challenges primarily within the nanobio-domain but not limited hereto. Exploring the full potential of this new `drone-like' light-printed, light-driven, light-actuated micro- and nanorobotics in challenging geometries requires a versatile and real-time reconfigurable light addressing that can dynamically track a plurality of tiny tools in 3D to ensure real-time continuous light-delivery on the fly. Our latest developments in this new and exciting research area will be reviewed.

Ultraminiature Broadband Light Source and Method of Manufacturing Same

NASA Technical Reports Server (NTRS)

Tuma, Margaret L. (Inventor); Collura, Joseph S. (Inventor); Helvajian, Henry (Inventor); Pocha, Michael D. (Inventor); Meyer, Glenn A. (Inventor); McConaghy, Charles F. (Inventor); Olsen, Barry L. (Inventor); Hansen, William W. (Inventor)

2010-01-01

An ultraminiature light source using a double-spiral shaped tungsten filament includes end contact portions which are separated to allow for radial and length-wise unwinding of the spiral. The double-spiral filament is spaced relatively far apart at the end portions thereof so that contact between portions of the filament upon expansion is avoided. The light ource is made by fabricating a double-spiral ultraminiature tungsten filament from tungsten foil and housing the filament in a ceramic package having a reflective bottom and a well wherein the filament is suspended. A vacuum furnace brazing process attaches the filament to contacts of the ceramic package. Finally, a cover with a transparent window is attached onto the top of the ceramic package by solder reflow in a second vacuum furnace process to form a complete hermetically sealed package.

Current use and potential of additive manufacturing for optical applications

NASA Astrophysics Data System (ADS)

Brunelle, Matthew; Ferralli, Ian; Whitsitt, Rebecca; Medicus, Kate

2017-10-01

Additive manufacturing, or 3D printing, has become widely used in recent years for the creation of both prototype and end-use parts. Because the parts are created in a layer-by-layer manner, the flexibility of additive manufacturing is unparalleled and has opened the design space to enable features like undercuts and internal channels which cannot exist on traditional, subtractively manufactured parts. This flexibility can also be leveraged for optical applications. This paper outlines some of the current uses of 3D printing in the optical manufacturing process at Optimax. Several materials and additive technologies are utilized, including polymer printing through fused deposition modeling, which creates parts by depositing a softened thermoplastic filament in a layerwise fashion. Stereolithography, which uses light to cure layers of a photopolymer resin, will also be discussed. These technologies are used to manufacture functional prototypes, fixtures, sealed housings, and other components. Additionally, metal printing through selective laser melting, which uses a laser to melt metal powder layers into a dense solid, will be discussed due to the potential to manufacture thermally stable opticalmechanical assembly frameworks and functional optics. Examples of several additively manufactured optical components will be shown.

Effect of curing mode on the micro-mechanical properties of dual-cured self-adhesive resin cements.

PubMed

Ilie, Nicoleta; Simon, Alexander

2012-04-01

Light supplying to luting resin cements is impeded in several clinical situations, causing us to question whether materials can properly be cured to achieve adequately (or adequate) mechanical properties. The aim of this study was therefore to analyse the effect of light on the micro-mechanical properties of eight popular dual-cured self-adhesive resin cements by comparing them with two conventional, also dual-cured, resin cements. Four different curing procedures were applied: auto-polymerisation (dark curing) and light curing (LED unit, Freelight 2, 20 s) by applying the unit directly on the samples' surface, at a distance of 5 and 10 mm. Twenty minutes after curing, the samples were stored for 1 week at 37°C in a water-saturated atmosphere. The micro-mechanical properties-Vickers hardness, modulus of elasticity, creep and elastic/plastic deformation-were measured. Data were analysed with multivariate ANOVA followed by Tukey's test and partial eta-squared statistics (p < 0.05). A very strong influence of the material as well as filler volume and weight on the micro-mechanical properties was measured, whereas the influence of the curing procedure and type of cement-conventional or self-adhesive-was generally low. The influence of light on the polymerisation process was material dependent, with four different behaviour patterns to be distinguished. As a material category, significantly higher micro-mechanical properties were measured for the conventional compared to the self-adhesive resin cements, although this difference was low. Within the self-adhesive resin cements group, the variation in micro-mechanical properties was high. The selection of suitable resin cements should be done by considering, besides its adhesive properties, its micro-mechanical properties and curing behaviour also.

Visible-Light-Driven BiOI-Based Janus Micromotor in Pure Water.

PubMed

Dong, Renfeng; Hu, Yan; Wu, Yefei; Gao, Wei; Ren, Biye; Wang, Qinglong; Cai, Yuepeng

2017-02-08

Light-driven synthetic micro-/nanomotors have attracted considerable attention due to their potential applications and unique performances such as remote motion control and adjustable velocity. Utilizing harmless and renewable visible light to supply energy for micro-/nanomotors in water represents a great challenge. In view of the outstanding photocatalytic performance of bismuth oxyiodide (BiOI), visible-light-driven BiOI-based Janus micromotors have been developed, which can be activated by a broad spectrum of light, including blue and green light. Such BiOI-based Janus micromotors can be propelled by photocatalytic reactions in pure water under environmentally friendly visible light without the addition of any other chemical fuels. The remote control of photocatalytic propulsion by modulating the power of visible light is characterized by velocity and mean-square displacement analysis of optical video recordings. In addition, the self-electrophoresis mechanism has been confirmed for such visible-light-driven BiOI-based Janus micromotors by demonstrating the effects of various coated layers (e.g., Al 2 O 3 , Pt, and Au) on the velocity of motors. The successful demonstration of visible-light-driven Janus micromotors holds a great promise for future biomedical and environmental applications.

Plasma-based EUV light source

DOEpatents

Shumlak, Uri; Golingo, Raymond; Nelson, Brian A.

2010-11-02

Various mechanisms are provided relating to plasma-based light source that may be used for lithography as well as other applications. For example, a device is disclosed for producing extreme ultraviolet (EUV) light based on a sheared plasma flow. The device can produce a plasma pinch that can last several orders of magnitude longer than what is typically sustained in a Z-pinch, thus enabling the device to provide more power output than what has been hitherto predicted in theory or attained in practice. Such power output may be used in a lithography system for manufacturing integrated circuits, enabling the use of EUV wavelengths on the order of about 13.5 nm. Lastly, the process of manufacturing such a plasma pinch is discussed, where the process includes providing a sheared flow of plasma in order to stabilize it for long periods of time.

Gravity and light effects on the circadian clock of a desert beetle, Trigonoscelis gigas

NASA Technical Reports Server (NTRS)

Hoban-Higgins, T. M.; Alpatov, A. M.; Wassmer, G. T.; Rietveld, W. J.; Fuller, C. A.

2003-01-01

Circadian function is affected by exposure to altered ambient force environments. Under non-earth gravitational fields, both basic features of circadian rhythms and the expression of the clock responsible for these rhythms are altered. We examined the activity rhythm of the tenebrionid beetle, Trigonoscelis gigas, in conditions of microgravity (microG; spaceflight), earth's gravity (1 G) and 2 G (centrifugation). Data were recorded under a light-dark cycle (LD), constant light (LL), and constant darkness (DD). Free-running period (tau) was significantly affected by both the gravitational field and ambient light intensity. In DD, tau was longer under 2 G than under either 1 G or microG. In addition, tauLL was significantly different from tauDD under microG and 1 G, but not under 2 G.

Fiber optic engine for micro projection display.

PubMed

Arabi, Hesam Edin; An, Sohee; Oh, Kyunghwan

2010-03-01

A novel compact optical engine for a micro projector display is experimentally demonstrated, which is composed of RGB light sources, a tapered 3 x 1 Fiber Optic Color Synthesizer (FOCS) along with a fiberized ball-lens, and a two dimensional micro electromechanical scanning mirror. In the proposed optical engine, we successfully employed an all-fiber beam shaping technique combining optical fiber taper and fiberized ball lens that can render a narrow beam and enhance the resolution of the screened image in the far field. Optical performances of the proposed device assembly are investigated in terms of power loss, collimating strength of the collimator assembly, and color gamut of the output.

Electrical, spectral and optical performance of yellow-green and amber micro-pixelated InGaN light-emitting diodes

NASA Astrophysics Data System (ADS)

Gong, Z.; Liu, N. Y.; Tao, Y. B.; Massoubre, D.; Xie, E. Y.; Hu, X. D.; Chen, Z. Z.; Zhang, G. Y.; Pan, Y. B.; Hao, M. S.; Watson, I. M.; Gu, E.; Dawson, M. D.

2012-01-01

Micro-pixelated InGaN LED arrays operating at 560 and 600 nm, respectively, are demonstrated for what the authors believe to be the first time. Such devices offer applications in areas including bioinstrumentation, visible light communications and optoelectronic tweezers. The devices reported are based on new epitaxial structures, retaining conventional (0 0 0 1) orientation, but incorporating electron reservoir layers which enhance the efficiency of radiative combination in the active regions. A measured output optical power density up to 8 W cm-2 (4.4 W cm-2) has been achieved from a representative pixel of the yellow-green (amber) LED array, substantially higher than that from conventional broad-area reference LEDs fabricated from the same wafer material. Furthermore, these micro-LEDs can sustain a high current density, up to 4.5 kA cm-2, before thermal rollover. A significant blueshift of the emission wavelength with increasing injection current is observed, however. This blueshift saturates at 45 nm (50 nm) for the yellow-green (amber) LED array, and numerical simulations have been used to gain insight into the responsible mechanisms in this microstructured format of device. In the relatively low-current-density regime (<3.5 kA cm-2) the blueshift is attributable to both the screening of the piezoelectric field by the injected carriers and the band-filling effect, whereas in the high-current regime, it is mainly due to band-filling. Further development of the epitaxial wafer material is expected to improve the current-dependent spectral stability.

Micro-position sensor using faraday effect

DOEpatents

McElfresh, Michael [Livermore, CA; Lucas, Matthew [Pittsburgh, PA; Silveira, Joseph P [Tracy, CA; Groves, Scott E [Brentwood, CA

2007-02-27

A micro-position sensor and sensing system using the Faraday Effect. The sensor uses a permanent magnet to provide a magnetic field, and a magneto-optic material positioned in the magnetic field for rotating the plane of polarization of polarized light transmitted through the magneto-optic material. The magnet is independently movable relative to the magneto-optic material so as to rotate the plane of polarization of the polarized light as a function of the relative position of the magnet. In this manner, the position of the magnet relative to the magneto-optic material may be determined from the rotated polarized light. The sensing system also includes a light source, such as a laser or LED, for producing polarized light, and an optical fiber which is connected to the light source and to the magneto-optic material at a sensing end of the optical fiber. Processing electronics, such as a polarimeter, are also provided for determining the Faraday rotation of the plane of polarization of the back-reflected polarized light to determine the position of the magnet relative to the sensing end of the optical fiber.

[Trial manufacture of a plunger shield for a disposable plastic syringe].

PubMed

Murakami, Shigeki; Emoto, Takashi; Mori, Hiroshige; Fujita, Katsuhisa; Kubo, Naoki

2008-08-20

A syringe-type radiopharmaceutical being supplied by a manufacturer has a syringe shield and a plunger shield, whereas an in-hospital labeling radiopharmaceutical is administered by a disposable plastic syringe without the plunger shield. In cooperation with Nihon Medi-Physics Co. Ltd., we have produced a new experimental plunger shield for the disposable plastic syringe. In order to evaluate this shielding effect, we compared the leaked radiation doses of our plunger shield with those of the syringe-type radiopharmaceutical (Medi shield type). Our plunger shield has a lead plate of 21 mm in diameter and 3 mm thick. This shield is equipped with the plunger-end of a disposal plastic syringe. We sealed 99mTc solution into a plastic syringe (Terumo Co.) of 5 ml with our plunger shield and Medi shield type of 2 ml. We measured leaked radiation doses around syringes using fluorescent glass dosimeters (Dose Ace). The number of measure points was 18. The measured doses were converted to 70 microm dose equivalent at 740 MBq of radioactivity. The results of our plunger shield and the Medi shield type were as follows: 4-13 microSv/h and 3-14 microSv/h at shielding areas, 3-545 microSv/h and 6-97 microSv/h at non-shielding areas, 42-116 microSv/h and 88-165 microSv/h in the vicinity of the syringe shield, and 1071 microSv/h and 1243 microSv/h at the front of the needle. For dose rates of shielding areas around the syringe, the shielding effects were approximately the same as those of the Medi shield type. In conclusion, our plunger shield may be useful for reducing finger exposure during the injection of an in-hospital labeled radiopharmaceutical.

Printing method for organic light emitting device lighting

NASA Astrophysics Data System (ADS)

Ki, Hyun Chul; Kim, Seon Hoon; Kim, Doo-Gun; Kim, Tae-Un; Kim, Snag-Gi; Hong, Kyung-Jin; So, Soon-Yeol

2013-03-01

Organic Light Emitting Device (OLED) has a characteristic to change the electric energy into the light when the electric field is applied to the organic material. OLED is currently employed as a light source for the lighting tools because research has extensively progressed in the improvement of luminance, efficiency, and life time. OLED is widely used in the plate display device because of a simple manufacture process and high emitting efficiency. But most of OLED lighting projects were used the vacuum evaporator (thermal evaporator) with low molecular. Although printing method has lower efficiency and life time of OLED than vacuum evaporator method, projects of printing OLED actively are progressed because was possible to combine with flexible substrate and printing technology. Printing technology is ink-jet, screen printing and slot coating. This printing method allows for low cost and mass production techniques and large substrates. In this research, we have proposed inkjet printing for organic light-emitting devices has the dominant method of thick film deposition because of its low cost and simple processing. In this research, the fabrication of the passive matrix OLED is achieved by inkjet printing, using a polymer phosphorescent ink. We are measured optical and electrical characteristics of OLED.

Process Capability of High Speed Micro End-Milling of Inconel 718 with Minimum Quantity Lubrication

NASA Astrophysics Data System (ADS)

Rahman, Mohamed Abd; Yeakub Ali, Mohammad; Rahman Shah Rosli, Abdul; Banu, Asfana

2017-03-01

The demand for micro-parts is expected to grow and micro-machining has been shown to be a viable manufacturing process to produce these products. These micro-products may be produced from hard-to-machine materials such as superalloys under little or no metal cutting fluids to reduce machining cost or drawbacks associated with health and environment. This project aims to investigate the capability of micro end-milling process of Inconel 718 with minimum quantity lubrication (MQL). Microtools DT-110 multi-process micro machine was used to machine 10 micro-channels with MQL and 10 more under dry condition while maintaining the same machining parameters. The width of the micro-channels was measured using digital microscope and used to determine the process capability indices, Cp and Cpk. QI Macros SPC for Excel was used to analyze the resultant machining data. The results indicated that micro end-milling process of Inconel 718 was not capable under both MQL and dry cutting conditions as indicated by the Cp values of less than 1.0. However, the use of MQL helped the process to be more stable and capable. Results obtained showed that the process variation was greatly reduced by using MQL in micro end-milling of Inconel 718.

Mitigation and control of the overcuring effect in mask projection micro-stereolithography

NASA Astrophysics Data System (ADS)

O'Neill, Paul F.; Kent, Nigel; Brabazon, Dermot

2017-10-01

Mask Projection micro-Stereolithography (MPμSL) is an additive manufacturing technique capable of producing solid parts with micron-scale resolution from a vat of photocurable liquid polymer resin. Although the physical mechanism remains the same, the process differs from traditional laser-galvanometer based stereolithography (SL) in its use of a dynamic mask UV projector, or digital light processor (DLP), which cures each location within each 3D layer at the same time. One area where MPµSL has garnered considerable attention is in the field of microfluidics and Lab-on-a-Chip, where complex multistep microfabrication techniques adopted from the semiconductor industry are still widely used, and where MPµSL offers the ability to fabricate completely encapsulated fluidic channels in a single step and at low cost [1-3]. However, a significant obstacle exists in the prevention of channel blockage due to overcuring of the polymer resin [4, 5]. Overcuring can be attributed to the so-called `back side effect' [2] which occurs during the build process as light from successive layers penetrates into the resin to a depth greater than the layer thickness. This effect is most prevalent in channels or features oriented horizontally (in a parallel plane to that of the build platform). Currently there are two main approaches in controlling the cure depth; 1. the chemical approach, which involves doping the resin material with a chemical light absorber [6-8]; and 2. by improving the system's hardware and optical elements to improve the homogeneity of the light dosage and control the cure depth [9]. Here we investigate a third approach through modification of the 3D CAD file prior to printing to mitigate for UV light leakage from successive build layers. Although used here in conjunction with the MPμSL technique, this approach can be applied to a range of SL techniques to improve printer resolution and enable production of internal features with higher dimensional accuracy.

Assessment of end-of-life design in solid-state lighting

NASA Astrophysics Data System (ADS)

Dzombak, Rachel; Padon, Jack; Salsbury, Josh; Dillon, Heather

2017-08-01

Consumers in the US market and across the globe are beginning to widely adopt light emitting diode (LED) lighting products while the technology continues to undergo significant changes. While LED products are evolving to consume less energy, they are also more complex than traditional lighting products with a higher number of parts and a larger number of electronic components. Enthusiasm around the efficiency and long expected life span of LED lighting products is valid, but research to optimize product characteristics and design is needed. This study seeks to address that gap by characterizing LED lighting products' suitability for end of life (EOL) recycling and disposal. The authors disassembled and assessed 17 different lighting products to understand how designs differ between brands and manufacture year. Products were evaluated based on six parameters to quantify the design. The analysis indicates that while the efficiency of LED products has improved dramatically in the recent past, product designers and manufacturers could incorporate design strategies to improve environmental performance of lighting products at end-of-life.

Cartilage Tissue Engineering with Silk Fibroin Scaffolds Fabricated by Indirect Additive Manufacturing Technology.

PubMed

Chen, Chih-Hao; Liu, Jolene Mei-Jun; Chua, Chee-Kai; Chou, Siaw-Meng; Shyu, Victor Bong-Hang; Chen, Jyh-Ping

2014-03-13

Advanced tissue engineering (TE) technology based on additive manufacturing (AM) can fabricate scaffolds with a three-dimensional (3D) environment suitable for cartilage regeneration. Specifically, AM technology may allow the incorporation of complex architectural features. The present study involves the fabrication of 3D TE scaffolds by an indirect AM approach using silk fibroin (SF). From scanning electron microscopic observations, the presence of micro-pores and interconnected channels within the scaffold could be verified, resulting in a TE scaffold with both micro- and macro-structural features. The intrinsic properties, such as the chemical structure and thermal characteristics of SF, were preserved after the indirect AM manufacturing process. In vitro cell culture within the SF scaffold using porcine articular chondrocytes showed a steady increase in cell numbers up to Day 14. The specific production (per cell basis) of the cartilage-specific extracellular matrix component (collagen Type II) was enhanced with culture time up to 12 weeks, indicating the re-differentiation of chondrocytes within the scaffold. Subcutaneous implantation of the scaffold-chondrocyte constructs in nude mice also confirmed the formation of ectopic cartilage by histological examination and immunostaining.

Cartilage Tissue Engineering with Silk Fibroin Scaffolds Fabricated by Indirect Additive Manufacturing Technology

PubMed Central

Chen, Chih-Hao; Liu, Jolene Mei-Jun; Chua, Chee-Kai; Chou, Siaw-Meng; Shyu, Victor Bong-Hang; Chen, Jyh-Ping

2014-01-01

Advanced tissue engineering (TE) technology based on additive manufacturing (AM) can fabricate scaffolds with a three-dimensional (3D) environment suitable for cartilage regeneration. Specifically, AM technology may allow the incorporation of complex architectural features. The present study involves the fabrication of 3D TE scaffolds by an indirect AM approach using silk fibroin (SF). From scanning electron microscopic observations, the presence of micro-pores and interconnected channels within the scaffold could be verified, resulting in a TE scaffold with both micro- and macro-structural features. The intrinsic properties, such as the chemical structure and thermal characteristics of SF, were preserved after the indirect AM manufacturing process. In vitro cell culture within the SF scaffold using porcine articular chondrocytes showed a steady increase in cell numbers up to Day 14. The specific production (per cell basis) of the cartilage-specific extracellular matrix component (collagen Type II) was enhanced with culture time up to 12 weeks, indicating the re-differentiation of chondrocytes within the scaffold. Subcutaneous implantation of the scaffold-chondrocyte constructs in nude mice also confirmed the formation of ectopic cartilage by histological examination and immunostaining. PMID:28788558

Study of 3D printing method for GRIN micro-optics devices

NASA Astrophysics Data System (ADS)

Wang, P. J.; Yeh, J. A.; Hsu, W. Y.; Cheng, Y. C.; Lee, W.; Wu, N. H.; Wu, C. Y.

2016-03-01

Conventional optical elements are based on either refractive or reflective optics theory to fulfill the design specifications via optics performance data. In refractive optical lenses, the refractive index of materials and radius of curvature of element surfaces determine the optical power and wavefront aberrations so that optical performance can be further optimized iteratively. Although gradient index (GRIN) phenomenon in optical materials is well studied for more than a half century, the optics theory in lens design via GRIN materials is still yet to be comprehensively investigated before realistic GRIN lenses are manufactured. In this paper, 3D printing method for manufacture of micro-optics devices with special features has been studied based on methods reported in the literatures. Due to the additive nature of the method, GRIN lenses in micro-optics devices seem to be readily achievable if a design methodology is available. First, derivation of ray-tracing formulae is introduced for all possible structures in GRIN lenses. Optics simulation program is employed for characterization of GRIN lenses with performance data given by aberration coefficients in Zernike polynomial. Finally, a proposed structure of 3D printing machine is described with conceptual illustration.

High temperature x-ray micro-tomography

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

MacDowell, Alastair A., E-mail: aamacdowell@lbl.gov; Barnard, Harold; Parkinson, Dilworth Y.

2016-07-27

There is increasing demand for 3D micro-scale time-resolved imaging of samples in realistic - and in many cases extreme environments. The data is used to understand material response, validate and refine computational models which, in turn, can be used to reduce development time for new materials and processes. Here we present the results of high temperature experiments carried out at the x-ray micro-tomography beamline 8.3.2 at the Advanced Light Source. The themes involve material failure and processing at temperatures up to 1750°C. The experimental configurations required to achieve the requisite conditions for imaging are described, with examples of ceramic matrixmore » composites, spacecraft ablative heat shields and nuclear reactor core Gilsocarbon graphite.« less

A front-end wafer-level microsystem packaging technique with micro-cap array

NASA Astrophysics Data System (ADS)

Chiang, Yuh-Min

2002-09-01

The back-end packaging process is the remaining challenge for the micromachining industry to commercialize microsystem technology (MST) devices at low cost. This dissertation presents a novel wafer level protection technique as a final step of the front-end fabrication process for MSTs. It facilitates improved manufacturing throughput and automation in package assembly, wafer level testing of devices, and enhanced device performance. The method involves the use of a wafer-sized micro-cap array, which consists of an assortment of small caps micro-molded onto a material with adjustable shapes and sizes to serve as protective structures against the hostile environments during packaging. The micro-cap array is first constructed by a micromachining process with micro-molding technique, then sealed to the device wafer at wafer level. Epoxy-based wafer-level micro cap array has been successfully fabricated and showed good compatibility with conventional back-end packaging processes. An adhesive transfer technique was demonstrated to seal the micro cap array with a MEMS device wafer. No damage or gross leak was observed while wafer dicing or later during a gross leak test. Applications of the micro cap array are demonstrated on MEMS, microactuators fabricated using CRONOS MUMPS process. Depending on the application needs, the micro-molded cap can be designed and modified to facilitate additional component functions, such as optical, electrical, mechanical, and chemical functions, which are not easily achieved in the device by traditional means. Successful fabrication of a micro cap array comprised with microlenses can provide active functions as well as passive protection. An optical tweezer array could be one possibility for applications of a micro cap with microlenses. The micro cap itself could serve as micro well for DNA or bacteria amplification as well.

Targeted Structural Optimization with Additive Manufacturing of Metals

NASA Technical Reports Server (NTRS)

Burt, Adam; Hull, Patrick

2015-01-01

The recent advances in additive manufacturing (AM) of metals have now improved the state-of-the-art such that traditionally non-producible parts can be readily produced in a cost-effective way. Because of these advances in manufacturing technology, structural optimization techniques are well positioned to supplement and advance this new technology. The goal of this project is to develop a structural design, analysis, and optimization framework combined with AM to significantly light-weight the interior of metallic structures while maintaining the selected structural properties of the original solid. This is a new state-of-the-art capability to significantly reduce mass, while maintaining the structural integrity of the original design, something that can only be done with AM. In addition, this framework will couple the design, analysis, and fabrication process, meaning that what has been designed directly represents the produced part, thus closing the loop on the design cycle and removing human iteration between design and fabrication. This fundamental concept has applications from light-weighting launch vehicle components to in situ resource fabrication.

"Micro to macro (M2M)"--A novel approach for intravenous delivery of propofol.

PubMed

Damitz, Robert; Chauhan, Anuj

2015-10-15

Propofol emulsions have limited shelf life and safety concerns for injection. Microemulsions of propofol are thermodynamically stable and simpler to manufacture, but cause additional pain on injection. We propose a novel micro to macro (M2M) approach of destabilizing a microemulsion immediately prior to injection. Microemulsions of propofol were prepared at two to three times the drug loadings of commercial formulations. We determined suitable microemulsion compositions which destabilize into macroemulsions after two or three fold dilutions with water. Droplet growth after dilution was measured with dynamic light scattering. Increasing solution turbidity after dilution was also measured optically with millisecond resolution. Experimental data was analyzed in the context of a coalescence model. Microemulsions rapidly coalesce into larger droplet size macroemulsions after dilution according to the phase diagram shift. The resulting macroemulsions are metastable retaining their droplet size for several hours. Droplet growth occurs on the order of seconds and a metastable size of about 1 micron is reached in minutes. Rates of droplet growth and metastable droplet sizes depend on the surfactant composition. The coalescence model predicts droplet growth with good agreement but only after accounting for the finite probability of coalescence from each collision. The M2M concept has been demonstrated for the anesthetic drug propofol which may improve stability and manufacturability in addition to reducing pain on injection. This approach could be adapted to other hydrophobic vesicant drugs as well. Copyright © 2015 Elsevier B.V. All rights reserved.

InGaN based micro light emitting diodes featuring a buried GaN tunnel junction

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

Malinverni, M., E-mail: marco.malinverni@epfl.ch; Martin, D.; Grandjean, N.

GaN tunnel junctions (TJs) are grown by ammonia molecular beam epitaxy. High doping levels are achieved with a net acceptor concentration close to ∼10{sup 20 }cm{sup −3}, thanks to the low growth temperature. This allows for the realization of p-n junctions with ultrathin depletion width enabling efficient interband tunneling. n-p-n structures featuring such a TJ exhibit low leakage current densities, e.g., <5 × 10{sup −5} A cm{sup −2} at reverse bias of 10 V. Under forward bias, the voltage is 3.3 V and 4.8 V for current densities of 20 A cm{sup −2} and 2000 A cm{sup −2}, respectively. The specific series resistance of the whole device ismore » 3.7 × 10{sup −4} Ω cm{sup 2}. Then micro-light emitting diodes (μ-LEDs) featuring buried TJs are fabricated. Excellent current confinement is demonstrated together with homogeneous electrical injection, as seen on electroluminescence mapping. Finally, the I-V characteristics of μ-LEDs with various diameters point out the role of the access resistance at the current aperture edge.« less

Manufactured Homes as Affordable Housing in Rural Areas. Rural Information Center Publication Series, No. 5.

ERIC Educational Resources Information Center

Czerniak, Robert, Comp.

This bibliography includes citations of approximately 60 books and articles pertaining to manufactured housing or "mobile homes," an important segment of the national housing industry. The availability of manufactured homes for low and moderate income groups is significant in light of skyrocketing new-housing costs. The South leads the nation with…

Machine learning for micro-tomography

NASA Astrophysics Data System (ADS)

Parkinson, Dilworth Y.; Pelt, Daniël. M.; Perciano, Talita; Ushizima, Daniela; Krishnan, Harinarayan; Barnard, Harold S.; MacDowell, Alastair A.; Sethian, James

2017-09-01

Machine learning has revolutionized a number of fields, but many micro-tomography users have never used it for their work. The micro-tomography beamline at the Advanced Light Source (ALS), in collaboration with the Center for Applied Mathematics for Energy Research Applications (CAMERA) at Lawrence Berkeley National Laboratory, has now deployed a series of tools to automate data processing for ALS users using machine learning. This includes new reconstruction algorithms, feature extraction tools, and image classification and recommen- dation systems for scientific image. Some of these tools are either in automated pipelines that operate on data as it is collected or as stand-alone software. Others are deployed on computing resources at Berkeley Lab-from workstations to supercomputers-and made accessible to users through either scripting or easy-to-use graphical interfaces. This paper presents a progress report on this work.

Search for Bs0 --> micro+ micro- and B0 --> micro+ micro- decays with 2 fb-1 of pp collisions.

PubMed

Aaltonen, T; Adelman, J; Akimoto, T; Albrow, M G; Alvarez González, B; Amerio, S; Amidei, D; Anastassov, A; Annovi, A; Antos, J; Aoki, M; Apollinari, G; Apresyan, A; Arisawa, T; Artikov, A; Ashmanskas, W; Attal, A; Aurisano, A; Azfar, F; Azzi-Bacchetta, P; Azzurri, P; Bacchetta, N; Badgett, W; Barbaro-Galtieri, A; Barnes, V E; Barnett, B A; Baroiant, S; Bartsch, V; Bauer, G; Beauchemin, P-H; Bedeschi, F; Bednar, P; Behari, S; Bellettini, G; Bellinger, J; Belloni, A; Benjamin, D; Beretvas, A; Beringer, J; Berry, T; Bhatti, A; Binkley, M; Bisello, D; Bizjak, I; Blair, R E; Blocker, C; Blumenfeld, B; Bocci, A; Bodek, A; Boisvert, V; Bolla, G; Bolshov, A; Bortoletto, D; Boudreau, J; Boveia, A; Brau, B; Bridgeman, A; Brigliadori, L; Bromberg, C; Brubaker, E; Budagov, J; Budd, H S; Budd, S; Burkett, K; Busetto, G; Bussey, P; Buzatu, A; Byrum, K L; Cabrera, S; Campanelli, M; Campbell, M; Canelli, F; Canepa, A; Carlsmith, D; Carosi, R; Carrillo, S; Carron, S; Casal, B; Casarsa, M; Castro, A; Catastini, P; Cauz, D; Cavalli-Sforza, M; Cerri, A; Cerrito, L; Chang, S H; Chen, Y C; Chertok, M; Chiarelli, G; Chlachidze, G; Chlebana, F; Cho, K; Chokheli, D; Chou, J P; Choudalakis, G; Chuang, S H; Chung, K; Chung, W H; Chung, Y S; Ciobanu, C I; Ciocci, M A; Clark, A; Clark, D; Compostella, G; Convery, M E; Conway, J; Cooper, B; Copic, K; Cordelli, M; Cortiana, G; Crescioli, F; Cuenca Almenar, C; Cuevas, J; Culbertson, R; Cully, J C; Dagenhart, D; Datta, M; Davies, T; de Barbaro, P; De Cecco, S; Deisher, A; De Lentdecker, G; De Lorenzo, G; Dell'orso, M; Demortier, L; Deng, J; Deninno, M; De Pedis, D; Derwent, P F; Di Giovanni, G P; Dionisi, C; Di Ruzza, B; Dittmann, J R; D'Onofrio, M; Donati, S; Dong, P; Donini, J; Dorigo, T; Dube, S; Efron, J; Erbacher, R; Errede, D; Errede, S; Eusebi, R; Fang, H C; Farrington, S; Fedorko, W T; Feild, R G; Feindt, M; Fernandez, J P; Ferrazza, C; Field, R; Flanagan, G; Forrest, R; Forrester, S; Franklin, M; Freeman, J C; Furic, I; Gallinaro, M; Galyardt, J; Garberson, F; Garcia, J E; Garfinkel, A F; Genser, K; Gerberich, H; Gerdes, D; Giagu, S; Giakoumopolou, V; Giannetti, P; Gibson, K; Gimmell, J L; Ginsburg, C M; Giokaris, N; Giordani, M; Giromini, P; Giunta, M; Glagolev, V; Glenzinski, D; Gold, M; Goldschmidt, N; Golossanov, A; Gomez, G; Gomez-Ceballos, G; Goncharov, M; González, O; Gorelov, I; Goshaw, A T; Goulianos, K; Gresele, A; Grinstein, S; Grosso-Pilcher, C; Grundler, U; Guimaraes da Costa, J; Gunay-Unalan, Z; Haber, C; Hahn, K; Hahn, S R; Halkiadakis, E; Hamilton, A; Han, B-Y; Han, J Y; Handler, R; Happacher, F; Hara, K; Hare, D; Hare, M; Harper, S; Harr, R F; Harris, R M; Hartz, M; Hatakeyama, K; Hauser, J; Hays, C; Heck, M; Heijboer, A; Heinemann, B; Heinrich, J; Henderson, C; Herndon, M; Heuser, J; Hewamanage, S; Hidas, D; Hill, C S; Hirschbuehl, D; Hocker, A; Hou, S; Houlden, M; Hsu, S-C; Huffman, B T; Hughes, R E; Husemann, U; Huston, J; Incandela, J; Introzzi, G; Iori, M; Ivanov, A; Iyutin, B; James, E; Jayatilaka, B; Jeans, D; Jeon, E J; Jindariani, S; Johnson, W; Jones, M; Joo, K K; Jun, S Y; Jung, J E; Junk, T R; Kamon, T; Kar, D; Karchin, P E; Kato, Y; Kephart, R; Kerzel, U; Khotilovich, V; Kilminster, B; Kim, D H; Kim, H S; Kim, J E; Kim, M J; Kim, S B; Kim, S H; Kim, Y K; Kimura, N; Kirsch, L; Klimenko, S; Klute, M; Knuteson, B; Ko, B R; Koay, S A; Kondo, K; Kong, D J; Konigsberg, J; Korytov, A; Kotwal, A V; Kraus, J; Kreps, M; Kroll, J; Krumnack, N; Kruse, M; Krutelyov, V; Kubo, T; Kuhlmann, S E; Kuhr, T; Kulkarni, N P; Kusakabe, Y; Kwang, S; Laasanen, A T; Lai, S; Lami, S; Lammel, S; Lancaster, M; Lander, R L; Lannon, K; Lath, A; Latino, G; Lazzizzera, I; Lecompte, T; Lee, J; Lee, J; Lee, Y J; Lee, S W; Lefèvre, R; Leonardo, N; Leone, S; Levy, S; Lewis, J D; Lin, C; Lin, C S; Linacre, J; Lindgren, M; Lipeles, E; Lister, A; Litvintsev, D O; Liu, T; Lockyer, N S; Loginov, A; Loreti, M; Lovas, L; Lu, R-S; Lucchesi, D; Lueck, J; Luci, C; Lujan, P; Lukens, P; Lungu, G; Lyons, L; Lys, J; Lysak, R; Lytken, E; Mack, P; Macqueen, D; Madrak, R; Maeshima, K; Makhoul, K; Maki, T; Maksimovic, P; Malde, S; Malik, S; Manca, G; Manousakis, A; Margaroli, F; Marino, C; Marino, C P; Martin, A; Martin, M; Martin, V; Martínez, M; Martínez-Ballarín, R; Maruyama, T; Mastrandrea, P; Masubuchi, T; Mattson, M E; Mazzanti, P; McFarland, K S; McIntyre, P; McNulty, R; Mehta, A; Mehtala, P; Menzemer, S; Menzione, A; Merkel, P; Mesropian, C; Messina, A; Miao, T; Miladinovic, N; Miles, J; Miller, R; Mills, C; Milnik, M; Mitra, A; Mitselmakher, G; Miyake, H; Moed, S; Moggi, N; Moon, C S; Moore, R; Morello, M; Movilla Fernandez, P; Mülmenstädt, J; Mukherjee, A; Muller, Th; Mumford, R; Murat, P; Mussini, M; Nachtman, J; Nagai, Y; Nagano, A; Naganoma, J; Nakamura, K; Nakano, I; Napier, A; Necula, V; Neu, C; Neubauer, M S; Nielsen, J; Nodulman, L; Norman, M; Norniella, O; Nurse, E; Oh, S H; Oh, Y D; Oksuzian, I; Okusawa, T; Oldeman, R; Orava, R; Osterberg, K; Pagan Griso, S; Pagliarone, C; Palencia, E; Papadimitriou, V; Papaikonomou, A; Paramonov, A A; Parks, B; Pashapour, S; Patrick, J; Pauletta, G; Paulini, M; Paus, C; Pellett, D E; Penzo, A; Phillips, T J; Piacentino, G; Piedra, J; Pinera, L; Pitts, K; Plager, C; Pondrom, L; Portell, X; Poukhov, O; Pounder, N; Prakoshyn, F; Pronko, A; Proudfoot, J; Ptohos, F; Punzi, G; Pursley, J; Rademacker, J; Rahaman, A; Ramakrishnan, V; Ranjan, N; Redondo, I; Reisert, B; Rekovic, V; Renton, P; Rescigno, M; Richter, S; Rimondi, F; Ristori, L; Robson, A; Rodrigo, T; Rogers, E; Rolli, S; Roser, R; Rossi, M; Rossin, R; Roy, P; Ruiz, A; Russ, J; Rusu, V; Saarikko, H; Safonov, A; Sakumoto, W K; Salamanna, G; Saltó, O; Santi, L; Sarkar, S; Sartori, L; Sato, K; Savoy-Navarro, A; Scheidle, T; Schlabach, P; Schmidt, E E; Schmidt, M A; Schmidt, M P; Schmitt, M; Schwarz, T; Scodellaro, L; Scott, A L; Scribano, A; Scuri, F; Sedov, A; Seidel, S; Seiya, Y; Semenov, A; Sexton-Kennedy, L; Sfyria, A; Shalhout, S Z; Shapiro, M D; Shears, T; Shepard, P F; Sherman, D; Shimojima, M; Shochet, M; Shon, Y; Shreyber, I; Sidoti, A; Sinervo, P; Sisakyan, A; Slaughter, A J; Slaunwhite, J; Sliwa, K; Smith, J R; Snider, F D; Snihur, R; Soderberg, M; Soha, A; Somalwar, S; Sorin, V; Spalding, J; Spinella, F; Spreitzer, T; Squillacioti, P; Stanitzki, M; St Denis, R; Stelzer, B; Stelzer-Chilton, O; Stentz, D; Strologas, J; Stuart, D; Suh, J S; Sukhanov, A; Sun, H; Suslov, I; Suzuki, T; Taffard, A; Takashima, R; Takeuchi, Y; Tanaka, R; Tecchio, M; Teng, P K; Terashi, K; Thom, J; Thompson, A S; Thompson, G A; Thomson, E; Tipton, P; Tiwari, V; Tkaczyk, S; Toback, D; Tokar, S; Tollefson, K; Tomura, T; Tonelli, D; Torre, S; Torretta, D; Tourneur, S; Trischuk, W; Tu, Y; Turini, N; Ukegawa, F; Uozumi, S; Vallecorsa, S; van Remortel, N; Varganov, A; Vataga, E; Vázquez, F; Velev, G; Vellidis, C; Veszpremi, V; Vidal, M; Vidal, R; Vila, I; Vilar, R; Vine, T; Vogel, M; Volobouev, I; Volpi, G; Würthwein, F; Wagner, P; Wagner, R G; Wagner, R L; Wagner-Kuhr, J; Wagner, W; Wakisaka, T; Wallny, R; Wang, S M; Warburton, A; Waters, D; Weinberger, M; Wester, W C; Whitehouse, B; Whiteson, D; Wicklund, A B; Wicklund, E; Williams, G; Williams, H H; Wilson, P; Winer, B L; Wittich, P; Wolbers, S; Wolfe, C; Wright, T; Wu, X; Wynne, S M; Yagil, A; Yamamoto, K; Yamaoka, J; Yamashita, T; Yang, C; Yang, U K; Yang, Y C; Yao, W M; Yeh, G P; Yoh, J; Yorita, K; Yoshida, T; Yu, G B; Yu, I; Yu, S S; Yun, J C; Zanello, L; Zanetti, A; Zaw, I; Zhang, X; Zheng, Y; Zucchelli, S

2008-03-14

We have performed a search for B(s)(0) --> micro(+) micro(-) and B(0) --> micro(+) micro(-) decays in pp collisions at square root s = 1.96 TeV using 2 fb(-1) of integrated luminosity collected by the CDF II detector at the Fermilab Tevatron Collider. The observed number of B(s)(0) and B0 candidates is consistent with background expectations. The resulting upper limits on the branching fractions are B(B(s)0) --> micro(+) micro(-)) <5.8 x 10(-8) and B(B(0) --> micro(+) micro(-))<1.8 x 10(-8) at 95% C.L.

Research on sensor design for internet of things and laser manufacturing

NASA Astrophysics Data System (ADS)

Wang, Tao; Yao, Jianquan; Guo, Ling; Zhang, Yanchun

2010-12-01

In this paper, we will introduce the research on sensor design for IOT (Internet of Things) and laser manufacturing, and supporting the establishment of local area IOT. The main contents include studying on the structure designing of silicon micro tilt sensor, data acquisition and processing, addressing implanted and building Local Area IOT with wireless sensor network technology. At last, it is discussed the status and trends of the Internet of Things from the promoters, watchers, pessimists and doers.

Effects of pathogen reduction systems on platelet microRNAs, mRNAs, activation, and function

PubMed Central

Osman, Abdimajid; Hitzler, Walter E.; Meyer, Claudius U.; Landry, Patricia; Corduan, Aurélie; Laffont, Benoit; Boilard, Eric; Hellstern, Peter; Vamvakas, Eleftherios C.

2015-01-01

Pathogen reduction (PR) systems for platelets, based on chemically induced cross-linking and inactivation of nucleic acids, potentially prevent transfusion transmission of infectious agents, but can increase clinically significant bleeding in some clinical studies. Here, we documented the effects of PR systems on microRNA and mRNA levels of platelets stored in the blood bank, and assessed their impact on platelet activation and function. Unlike platelets subjected to gamma irradiation or stored in additive solution, platelets treated with Intercept (amotosalen + ultraviolet-A [UVA] light) exhibited significantly reduced levels of 6 of the 11 microRNAs, and 2 of the 3 anti-apoptotic mRNAs (Bcl-xl and Clusterin) that we monitored, compared with platelets stored in plasma. Mirasol (riboflavin + UVB light) treatment of platelets did not produce these effects. PR neither affected platelet microRNA synthesis or function nor induced cross-linking of microRNA-sized endogenous platelet RNA species. However, the reduction in the platelet microRNA levels induced by Intercept correlated with the platelet activation (p < 0.05) and an impaired platelet aggregation response to ADP (p < 0.05). These results suggest that Intercept treatment may induce platelet activation, resulting in the release of microRNAs and mRNAs from platelets. The clinical implications of this reduction in platelet nucleic acids secondary to Intercept remain to be established. PMID:24749844

[Design and experiment of micro biochemical detector based on micro spectrometer].

PubMed

Yu, Qing-hua; Wen, Zhi-yu; Chen, Gang; Dai, Wei-wei; Liu, Nian-ci; Wu, Xin

2012-03-01

According to the requirements of rapid detection of important life parameters for the sick and wounded, a new micro bio-chemical detection configuration was proposed utilizing continuous spectroscopy analysis, which was founded on MOEMS and embedded technology. The configuration was developed as so much research work was carried out on the detecting objects and methods. Important parameters such as stray light, absorbance linearity, absorbance ratability, stability and temperature accuracy of the instrument were tested, which are all in good agreement with the design requirements. Clinic tests show that it can detect multiple life parameters quickly (Na+, GLU, Hb eg.).

The impact of fit manufacturing on green manufacturing: A review

NASA Astrophysics Data System (ADS)

Qi, Ang Nian; Sin, Tan Chan; Fathullah, M.; Lee, C. C.

2017-09-01

Fit manufacturing and Green manufacturing are a new trend principle and concept. They are getting popular in industrial. This paper is identifying the impact between Fit manufacturing and Green manufacturing. Besides Fit manufacturing, Lean manufacturing, Agile manufacturing and Sustainable manufacturing gives big impacts to Green Manufacturing. On top of that, this paper also discuss the benefits of applying Fit manufacturing and Green manufacturing in industrial as well as environment. Hence, applications of Fit manufacturing and Green Manufacturing are increasing year by year.

Micro-optics: enabling technology for illumination shaping in optical lithography

NASA Astrophysics Data System (ADS)

Voelkel, Reinhard

2014-03-01

Optical lithography has been the engine that has empowered semiconductor industry to continually reduce the half-pitch for over 50 years. In early mask aligners a simple movie lamp was enough to illuminate the photomask. Illumination started to play a more decisive role when proximity mask aligners appeared in the mid-1970s. Off-axis illumination was introduced to reduce diffraction effects. For early projection lithography systems (wafer steppers), the only challenge was to collect the light efficiently to ensure short exposure time. When projection optics reached highest level of perfection, further improvement was achieved by optimizing illumination. Shaping the illumination light, also referred as pupil shaping, allows the optical path from reticle to wafer to be optimized and thus has a major impact on aberrations and diffraction effects. Highly-efficient micro-optical components are perfectly suited for this task. Micro-optics for illumination evolved from simple flat-top (fly's-eye) to annular, dipole, quadrupole, multipole and freeform illumination. Today, programmable micro-mirror arrays allow illumination to be changed on the fly. The impact of refractive, diffractive and reflective microoptics for photolithography will be discussed.

Scale effects and a method for similarity evaluation in micro electrical discharge machining

NASA Astrophysics Data System (ADS)

Liu, Qingyu; Zhang, Qinhe; Wang, Kan; Zhu, Guang; Fu, Xiuzhuo; Zhang, Jianhua

2016-08-01

Electrical discharge machining(EDM) is a promising non-traditional micro machining technology that offers a vast array of applications in the manufacturing industry. However, scale effects occur when machining at the micro-scale, which can make it difficult to predict and optimize the machining performances of micro EDM. A new concept of "scale effects" in micro EDM is proposed, the scale effects can reveal the difference in machining performances between micro EDM and conventional macro EDM. Similarity theory is presented to evaluate the scale effects in micro EDM. Single factor experiments are conducted and the experimental results are analyzed by discussing the similarity difference and similarity precision. The results show that the output results of scale effects in micro EDM do not change linearly with discharge parameters. The values of similarity precision of machining time significantly increase when scaling-down the capacitance or open-circuit voltage. It is indicated that the lower the scale of the discharge parameter, the greater the deviation of non-geometrical similarity degree over geometrical similarity degree, which means that the micro EDM system with lower discharge energy experiences more scale effects. The largest similarity difference is 5.34 while the largest similarity precision can be as high as 114.03. It is suggested that the similarity precision is more effective in reflecting the scale effects and their fluctuation than similarity difference. Consequently, similarity theory is suitable for evaluating the scale effects in micro EDM. This proposed research offers engineering values for optimizing the machining parameters and improving the machining performances of micro EDM.

Enhanced light scattering of the forbidden longitudinal optical phonon mode studied by micro-Raman spectroscopy on single InN nanowires.

PubMed

Schäfer-Nolte, E O; Stoica, T; Gotschke, T; Limbach, F A; Sutter, E; Sutter, P; Grützmacher, D; Calarco, R

2010-08-06

In the literature, there are controversies on the interpretation of the appearance in InN Raman spectra of a strong scattering peak in the energy region of the unscreened longitudinal optical (LO) phonons, although a shift caused by the phonon-plasmon interaction is expected for the high conductance observed in this material. Most measurements on light scattering are performed on ensembles of InN nanowires (NWs). However, it is important to investigate the behavior of individual nanowires and here we report on micro-Raman measurements on single nanowires. When changing the polarization direction of the incident light from parallel to perpendicular to the wire, the expected reduction of the Raman scattering was observed for transversal optical (TO) and E(2) phonon scattering modes, while a strong symmetry-forbidden LO mode was observed independently on the laser polarization direction. Single Mg- and Si-doped crystalline InN nanowires were also investigated. Magnesium doping results in a sharpening of the Raman peaks, while silicon doping leads to an asymmetric broadening of the LO peak. The results can be explained based on the influence of the high electron concentration with a strong contribution of the surface accumulation layer and the associated internal electric field.

Sensor fabrication method for in situ temperature and humidity monitoring of light emitting diodes.

PubMed

Lee, Chi-Yuan; Su, Ay; Liu, Yin-Chieh; Chan, Pin-Cheng; Lin, Chia-Hung

2010-01-01

In this work micro temperature and humidity sensors are fabricated to measure the junction temperature and humidity of light emitting diodes (LED). The junction temperature is frequently measured using thermal resistance measurement technology. The weakness of this method is that the timing of data capture is not regulated by any standard. This investigation develops a device that can stably and continually measure temperature and humidity. The device is light-weight and can monitor junction temperature and humidity in real time. Using micro-electro-mechanical systems (MEMS), this study minimizes the size of the micro temperature and humidity sensors, which are constructed on a stainless steel foil substrate (40 μm-thick SS-304). The micro temperature and humidity sensors can be fixed between the LED chip and frame. The sensitivities of the micro temperature and humidity sensors are 0.06±0.005 (Ω/°C) and 0.033 pF/%RH, respectively.

Efficient Light Extraction of Organic Light-Emitting Diodes on a Fully Solution-Processed Flexible Substrate

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

Tong, Kwing; Liu, Xiaofeng; Zhao, Fangchao

A flexible, nanocomposite substrate for maximizing light outcoupling efficiencies of organic light-emitting diodes (OLEDs) is introduced. In depth investigation is performed on designing the integrated strategy based on considerations of surface conductivity, microcavity tuning, and internal light scattering. The resulting nanocomposite substrate consists of silver nanowires as the electrode and a high-index polymer layer and a light-scattering layer for light extraction. It is able to outcouple both the waveguide and the substrate modes, two modes accounting for significant losses in OLED device efficiency. With enhanced light outcoupling, white OLEDs subsequently fabricated on the nanocomposite substrates demonstrate performance metrics of 107more » lm W -1 power efficiency and 49% external quantum efficiency at 1000 cd m -2. Thus, the nanocomposite substrate is fabricated by solution processes at low temperatures for potentially low manufacturing cost.« less

Efficient Light Extraction of Organic Light-Emitting Diodes on a Fully Solution-Processed Flexible Substrate

DOE PAGES

Tong, Kwing; Liu, Xiaofeng; Zhao, Fangchao; ...

2017-07-18

A flexible, nanocomposite substrate for maximizing light outcoupling efficiencies of organic light-emitting diodes (OLEDs) is introduced. In depth investigation is performed on designing the integrated strategy based on considerations of surface conductivity, microcavity tuning, and internal light scattering. The resulting nanocomposite substrate consists of silver nanowires as the electrode and a high-index polymer layer and a light-scattering layer for light extraction. It is able to outcouple both the waveguide and the substrate modes, two modes accounting for significant losses in OLED device efficiency. With enhanced light outcoupling, white OLEDs subsequently fabricated on the nanocomposite substrates demonstrate performance metrics of 107more » lm W -1 power efficiency and 49% external quantum efficiency at 1000 cd m -2. Thus, the nanocomposite substrate is fabricated by solution processes at low temperatures for potentially low manufacturing cost.« less

Towards manipulating relativistic laser pulses with micro-tube plasma lenses

PubMed Central

Ji, L. L.; Snyder, J.; Pukhov, A.; Freeman, R. R.; Akli, K. U.

2016-01-01

Efficient coupling of intense laser pulses to solid-density matter is critical to many applications including ion acceleration for cancer therapy. At relativistic intensities, the focus has been mainly on investigating various laser beams irradiating initially overdense flat interfaces with little or no control over the interaction. Here, we propose a novel approach that leverages recent advancements in 3D direct laser writing (DLW) of materials and high contrast lasers to manipulate the laser-matter interactions on the micro-scales. We demonstrate, via simulations, that usable intensities ≥1023 Wcm−2 could be achieved with current tabletop lasers coupled to micro-engineered plasma lenses. We show that these plasma optical elements act as a lens to focus laser light. These results open new paths to engineering light-matter interactions at ultra-relativistic intensities. PMID:26979657

Micro-optical elements produced using an photo-embossing technique in photopolymers

NASA Astrophysics Data System (ADS)

O'Neill, Feidhlim T.; Rowsome, Ita C.; Carr, Alun J.; Daniels, Stephen M.; Gleeson, Michael R.; Kelly, John V.; Close, Ciara; Lawrence, Justin R.; Sheridan, John T.

2005-09-01

Micro-optical devices are very important in current high-tech consumer items. The development of future products depends on both the evolution of fabrication techniques and on the development of new low cost mass production methods. Polymers offer ease of fabrication and low cost and are therefore excellent materials for the development of micro-optical devices. Polymer optical devices include passive optical elements, such as microlens arrays and waveguides, as well as active devices such as polymer based lasers. One of the most important areas of micro-optics is that of microlens design, manufacture and testing. The wide diversity of fabrication methods used for the production of these elements indicates their importance. One of these fabrication techniques is photo-embossing. The use of the photo-embossing technique and a photopolymer holographic recording material will be examined in this paper. A discussion of current attempts to model the fabrication process and a review of the experimental method will be given.

Advanced Micro/Nanostructures for Lithium Metal Anodes

PubMed Central

Zhang, Rui; Li, Nian‐Wu; Cheng, Xin‐Bing; Yin, Ya‐Xia

2017-01-01

Owning to their very high theoretical capacity, lithium metal anodes are expected to fuel the extensive practical applications in portable electronics and electric vehicles. However, unstable solid electrolyte interphase and lithium dendrite growth during lithium plating/stripping induce poor safety, low Coulombic efficiency, and short span life of lithium metal batteries. Lately, varies of micro/nanostructured lithium metal anodes are proposed to address these issues in lithium metal batteries. With the unique surface, pore, and connecting structures of different nanomaterials, lithium plating/stripping processes have been regulated. Thus the electrochemical properties and lithium morphologies have been significantly improved. These micro/nanostructured lithium metal anodes shed new light on the future applications for lithium metal batteries. PMID:28331792

Method of manufacturing a fully integrated and encapsulated micro-fabricated vacuum diode

DOEpatents

Resnick, Paul J.; Langlois, Eric

2014-08-26

Disclosed is an encapsulated micro-diode and a method for producing same. The method comprises forming a plurality columns in the substrate with a respective tip disposed at a first end of the column, the tip defining a cathode of the diode; disposing a sacrificial oxide layer on the substrate, plurality of columns and respective tips; forming respective trenches in the sacrificial oxide layer around the columns; forming an opening in the sacrificial oxide layer to expose a portion of the tips; depositing a conductive material in of the opening and on a surface of the substrate to form an anode of the diode; and removing the sacrificial oxide layer.

Fabrication of light water reactor tritium targets

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

Pilger, J.P.

1991-11-01

The mission of the Fabrication Development Task of the Tritium Target Development Project is: to produce a documented technology basis, including specifications and procedures for target rod fabrication; to demonstrate that light water tritium targets can be manufactured at a rate consistent with tritium production requirements; and to develop quality control methods to evaluate target rod components and assemblies, and establish correlations between evaluated characteristics and target rod performance. Many of the target rod components: cladding tubes, end caps, plenum springs, etc., have similar counterparts in LWR fuel rods. High production rate manufacture and inspection of these components has beenmore » adequately demonstrated by nuclear fuel rod manufacturers. This summary describes the more non-conventional manufacturing processes and inspection techniques developed to fabricate target rod components whose manufacturability at required production rates had not been previously demonstrated.« less

Micro-Fabricated Perforated Polymer Devices for Long-Term Drug Delivery

DTIC Science & Technology

2011-02-24

conventional manufacturing methods. We have used a biocompatible polymer ( polyimide ) to serve as a reservoir and photolithographically produced microholes for...RIE with ICP source was used to etch holes on polyimide surface. Biocompatible materials Ti, SiO2 and SiNx were studied as mask materials. Ti film...used to fabricate micro holes on the surface of polyimide tubes. Several materials have been used to form the etching mask, including titanium film

Direct micro-CT observation confirms the induction of embolism upon xylem cutting under tension

USDA-ARS?s Scientific Manuscript database

We used two different Synchrotron-based micro-CT facilities (SLS: Swiss Light Source, Villigen, Switzerland, and ALS: Advanced Light Source, Berkeley, CA USA) to test the excision artifact described by Wheeler et al. (2013). Specifically, we examined the impact of cutting xylem under tension and und...

46 CFR 161.013-13 - Manufacturer certification and labeling.

Code of Federal Regulations, 2011 CFR

2011-10-01

...) Manufacturer's name; (2) Replacement battery type; (3) Lamp size; and (4) The following words— “Night Visual... Only.” (c) If an electric light is designed for use with dry cell batteries the label must advise the consumer on the battery replacement schedule which under normal conditions would maintain performance...

46 CFR 161.013-13 - Manufacturer certification and labeling.

Code of Federal Regulations, 2014 CFR

2014-10-01

...) Manufacturer's name; (2) Replacement battery type; (3) Lamp size; and (4) The following words— “Night Visual... Only.” (c) If an electric light is designed for use with dry cell batteries the label must advise the consumer on the battery replacement schedule which under normal conditions would maintain performance...

46 CFR 161.013-13 - Manufacturer certification and labeling.

Code of Federal Regulations, 2010 CFR

2010-10-01

...) Manufacturer's name; (2) Replacement battery type; (3) Lamp size; and (4) The following words— “Night Visual... Only.” (c) If an electric light is designed for use with dry cell batteries the label must advise the consumer on the battery replacement schedule which under normal conditions would maintain performance...

46 CFR 161.013-13 - Manufacturer certification and labeling.

Code of Federal Regulations, 2012 CFR

2012-10-01

...) Manufacturer's name; (2) Replacement battery type; (3) Lamp size; and (4) The following words— “Night Visual... Only.” (c) If an electric light is designed for use with dry cell batteries the label must advise the consumer on the battery replacement schedule which under normal conditions would maintain performance...

46 CFR 161.013-13 - Manufacturer certification and labeling.

Code of Federal Regulations, 2013 CFR

2013-10-01

...) Manufacturer's name; (2) Replacement battery type; (3) Lamp size; and (4) The following words— “Night Visual... Only.” (c) If an electric light is designed for use with dry cell batteries the label must advise the consumer on the battery replacement schedule which under normal conditions would maintain performance...

Contour scanning of textile preforms using a light-section sensor for the automated manufacturing of fibre-reinforced plastics

NASA Astrophysics Data System (ADS)

Schmitt, R.; Niggemann, C.; Mersmann, C.

2008-04-01

Fibre-reinforced plastics (FRP) are particularly suitable for components where light-weight structures with advanced mechanical properties are required, e.g. for aerospace parts. Nevertheless, many manufacturing processes for FRP include manual production steps without an integrated quality control. A vital step in the process chain is the lay-up of the textile preform, as it greatly affects the geometry and the mechanical performance of the final part. In order to automate the FRP production, an inline machine vision system is needed for a closed-loop control of the preform lay-up. This work describes the development of a novel laser light-section sensor for optical inspection of textile preforms and its integration and validation in a machine vision prototype. The proposed method aims at the determination of the contour position of each textile layer through edge scanning. The scanning route is automatically derived by using texture analysis algorithms in a preliminary step. As sensor output a distinct stage profile is computed from the acquired greyscale image. The contour position is determined with sub-pixel accuracy using a novel algorithm based on a non-linear least-square fitting to a sigmoid function. The whole contour position is generated through data fusion of the measured edge points. The proposed method provides robust process automation for the FRP production improving the process quality and reducing the scrap quota. Hence, the range of economically feasible FRP products can be increased and new market segments with cost sensitive products can be addressed.

Single-mode light source fabrication based on colloidal quantum dots

NASA Astrophysics Data System (ADS)

Xu, Jianfeng; Chen, Bing; Baig, Sarfaraz; Wang, Michael R.

2009-02-01

There are huge market demands for innovative, cheap and efficient light sources, including light emitting devices, such as LEDs and lasers. However, the light source development in the visible spectral range encounters significant difficulties these years. The available visible wavelength LEDs or lasers are few, large and expensive. The main challenge lies at the lack of efficient light media. Semiconductor nanocrystal quantum dots (QDs) have recently commanded considerable attention. As a result of quantum confinement effect, the emission color of these QDs covers the whole visible spectral range and can be modified dramatically by simply changing their size. Such spectral tunability, together with large photoluminescence quantum yield and photostability, make QDs attractive for potential applications in a variety of light emitting technologies. However, there are still several technical problems that hinder their application as light sources. One main issue is how to fabricate these QDs into a solid state device while still retaining their original optical emission properties. A vacuum assisted micro-fluidic fabrication of guided wave devices has demonstrated low waveguide propagation loss, lower crosstalk, and improved waveguide structures. We report herein the combination of the excellent emission properties of QDs and novel vacuum assisted micro-fluidic photonic structure fabrication technique to realize single-mode efficient light sources.

Investigations on Mechanical Behaviour of Micro Graphite Particulates Reinforced Al-7Si Alloy Composites

NASA Astrophysics Data System (ADS)

Nagaraj, N.; Mahendra, K. V.; Nagaral, Madeva

2018-02-01

Micro particulates reinforced metal matrix composites are finding wide range of applications in automotive and sports equipment manufacturing industries. In the present study, an attempt has been made to develop Al-7Si-micro graphite particulates reinforced composites by using liquid melt method. 3 and 6 wt. % of micro graphite particulates were added to the Al-7Si base matrix. Microstructural characterization was done by using scanning electron microscope and energy dispersive spectroscope. Mechanical behaviour of Al-7Si-3 and 6 wt. % composites were evaluated as per ASTM standards. Scanning electron micrographs revealed the uniform distribution of micro graphite particulates in the Al-7Si alloy matrix. EDS analysis confirmed the presence of B and C elements in graphite reinforced composites. Further, it was noted that ultimate tensile and yield strength of Al-7Si alloy increased with the addition of 3 and 6wt. % of graphite particulates. Hardness of graphite reinforced composites was lesser than the base matrix.

Frequency Invariability of (Pb,La)(Zr,Ti)O₃ Antiferroelectric Thick-Film Micro-Cantilevers.

PubMed

An, Kun; Jin, Xuechen; Meng, Jiang; Li, Xiao; Ren, Yifeng

2018-05-13

Micro-electromechanical systems comprising antiferroelectric layers can offer both actuation and transduction to integrated technologies. Micro-cantilevers based on the (Pb 0.97 La 0.02 )(Zr 0.95 Ti 0.05 )O₃ (PLZT) antiferroelectric thick film are fabricated by the micro-nano manufacturing process, to utilize the effect of phase transition induced strain and sharp phase switch of antiferroelectric materials. When micro-cantilevers made of antiferroelectric thick films were driven by sweep voltages, there were two resonant peaks corresponding to the natural frequency shift from 27.8 to 27.0 kHz, before and after phase transition. This is the compensation principle for the PLZT micro-cantilever to tune the natural frequency by the amplitude modulation of driving voltage, rather than of frequency modulation. Considering the natural frequency shift about 0.8 kHz and the frequency tuning ability about 156 Hz/V before the phase transition, this can compensate the frequency shift caused by increasing temperature by tuning only the amplitude of driving voltage, when the ultrasonic micro-transducer made of antiferroelectric thick films works for such a long period. Therefore, antiferroelectric thick films with hetero-structures incorporated into PLZT micro-cantilevers not only require a lower driving voltage (no more than 40 V) than rival bulk piezoelectric ceramics, but also exhibit better performance of frequency invariability, based on the amplitude modulation.

Reading from Scratch - A Vision-System for Reading Data on Micro-structured Surfaces

NASA Astrophysics Data System (ADS)

Dragon, Ralf; Becker, Christian; Rosenhahn, Bodo; Ostermann, Jörn

Labeling and marking industrial manufactured objects gets increasingly important nowadays because of novel material properties and plagiarism. As part of the Collaborative Research Center 653 which investigates micro-structured metallic surfaces for inherent mechanical data storage, we research into a stable and reliable optical readout of the written data. Since this comprises a qualitative surface reconstruction, we use directed illumination to make the micro structures visible. Then we apply a spectral analysis to obtain image partitioning and perform signal tracking enhanced by a customized Hidden Markov Model. In this paper, we derive the algorithms used and demonstrate reading data from a surface with 1.6kbit/cm2 from a micro-structured groove which varies by only 3μ m in depth (thus a “scratch”). We demonstrate the system’s robustness with experiments with real and artificially-rendered surfaces.

The effects of polymers' visco-elastoplastic properties on the micro cavities filling step of hot embossing process

NASA Astrophysics Data System (ADS)

Cheng, Gang; Barrière, Thierry

2018-05-01

The hot embossing process has been widely used in the manufacturing of polymer components, especially for the fabrication of micro or nano components. The significant advantage of the hot embossing process compared to the traditional injection moulding process is the excellent effective filling ratio for the high aspect ratio components and large surface structural components. The lack of material behavior modeling and numerical simulation limits the further development the hot embossing process, especially at the micro and nano scales. In this paper, a visco-elastoplastic behavior law has been proposed to describe the amorphous thermoplastic polymer mechanical properties in the hot embossing processing temperature range, which is lightly above their glass transition temperature. Uniaxial compression tests have been carried out in order to investigate the amorphous thermoplastic polymers properties. The material parameters in the visco-elastoplastic model have been identified according to the experimental results. A 3D numerical model has been created in the simulation software, which is based on the finite element method. The numerical simulation of the filling step of the hot embossing process has been effectuated by taking into account the viscous, elastic and plastic behaviors of thermoplastic polymers. The micro hot embossing process has been carried out using horizontal injection compression moulding equipment. A complete compression mould tool, equipped with the heating system, the cooling system, the ejection system and the vacuum system, has been designed and elaborated for this research work. The microfluidic devices based on the amorphous thermoplastic polymers have been successfully elaborated by hot embossing process. Proper agreement between the numerical simulation and the experimental elaboration has been obtained.

Three-Dimensionally Printed Micro-electromechanical Switches.

PubMed

Lee, Yongwoo; Han, Jungmin; Choi, Bongsik; Yoon, Jinsu; Park, Jinhee; Kim, Yeamin; Lee, Jieun; Kim, Dae Hwan; Kim, Dong Myong; Lim, Meehyun; Kang, Min-Ho; Kim, Sungho; Choi, Sung-Jin

2018-05-09

Three-dimensional (3D) printers have attracted considerable attention from both industry and academia and especially in recent years because of their ability to overcome the limitations of two-dimensional (2D) processes and to enable large-scale facile integration techniques. With 3D printing technologies, complex structures can be created using only a computer-aided design file as a reference; consequently, complex shapes can be manufactured in a single step with little dependence on manufacturer technologies. In this work, we provide a first demonstration of the facile and time-saving 3D printing of two-terminal micro-electromechanical (MEM) switches. Two widely used thermoplastic materials were used to form 3D-printed MEM switches; freely suspended and fixed electrodes were printed from conductive polylactic acid, and a water-soluble sacrificial layer for air-gap formation was printed from poly(vinyl alcohol). Our 3D-printed MEM switches exhibit excellent electromechanical properties, with abrupt switching characteristics and an excellent on/off current ratio value exceeding 10 6 . Therefore, we believe that our study makes an innovative contribution with implications for the development of a broader range of 3D printer applications (e.g., the manufacturing of various MEM devices and sensors), and the work highlights a uniquely attractive path toward the realization of 3D-printed electronics.

Advanced lighting guidelines: 1993. Final report

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

Eley, C.; Tolen, T.M.; Benya, J.R.

1993-12-31

The 1993 Advanced Lighting Guidelines document consists of twelve guidelines that provide an overview of specific lighting technologies and design application techniques utilizing energy-efficient lighting practice. Lighting Design Practice assesses energy-efficient lighting strategies, discusses lighting issues, and explains how to obtain quality lighting design and consulting services. Luminaires and Lighting Systems surveys luminaire equipment designed to take advantage of advanced technology lamp products and includes performance tables that allow for accurate estimation of luminaire light output and power input. The additional ten guidelines -- Computer-Aided Lighting Design, Energy-Efficient Fluorescent Ballasts, Full-Size Fluorescent Lamps, Compact Fluorescent Lamps, Tungsten-Halogen Lamps, Metal Halidemore » and HPS Lamps, Daylighting and Lumen Maintenance, Occupant Sensors, Time Scheduling Systems, and Retrofit Control Technologies -- each provide a product technology overview, discuss current products on the lighting equipment market, and provide application techniques. This document is intended for use by electric utility personnel involved in lighting programs, lighting designers, electrical engineers, architects, lighting manufacturers` representatives, and other lighting professionals.« less