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Conference on current developments in Lens design and optical engineering XIV

作者： Suarez-Romero, Jose G. Salas-Zuniga, Roberto Inst Tecnol Queretaro Av Tecnol SN Esc Escobedo Queretaro 76000 Qro Mexico Ctr Ingn & Tecnol SC Queretaro 76090 Qro Mexico

ISBN: (纸本)9780819496911

This work considers typical radiometers that measure the radiance of sources or of some surface (due to reflection). The most important thing in a radiometer is its optical cavity, which defines the solid angle of measurement. In case of instruments that use lenses, lens diameter and focal length define the solid angle. Radiometer design takes care that the solid angle subtended by the optical cavity be minor that the solid angle subtended by the source to be measured, however no considerations are taken on the length of the cavity. In this work it is discussed theoretical limitation in the design of radiometers, particularly the influence of radiometer length (the cavity length). Theory of partial coherence is used to obtain the instrument function and to show how the length of the instrument affects measurements.

关键词： Radiometers photometers partial coherence diffraction effects radiometry photometry

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Double micro-prism array design for reducing dispersion on prism-based stereo camera system

Double micro-prism array design for reducing dispersion on p...

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Conference on current developments in Lens design and optical engineering XIV

作者： Sun, Wen-Shing Chu, Pu-Yi Natl Cent Univ Dept Opt & Photon Chungli 32001 Taiwan

We apply a digital camera with two prism arrays to capture a stereo image of the corrected chromatic aberration and distortion. The doublet prisms are used to correct chromatic aberration. The camera distortion with t... 详细信息

ISBN: (纸本)9780819496911

关键词： stereo image two prism arrays chromatic aberration distortion

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Micro-optical elements for optical wireless applications

Micro-optical elements for optical wireless applications

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Conference on current developments in Lens design and optical engineering XIV

作者： Jin, Xian Guerrero, Daniel Klukas, Richard Holzman, Jonathan F. Univ British Columbia Sch Engn Integrated Opt Lab Kelowna BC V1V 1V7 Canada Univ British Columbia Sch Engn Posit & Navigat Signal Proc Lab Kelowna BC V1V 1V7 Canada

ISBN: (纸本)9780819496911

Customized high-contact-angle microlenses are presented for optical wireless communication (OWC) and optical wireless location (OWL) applications. These microlenses are fabricated by way of an electro-dispensing technique to establish wide field-of-views (FOVs). Each microlens is formed from dispensed UV-curable polymer with pressure-control defining the microlens volume and a voltage on the metal needle tip defining the microlens shape (by way of electrowetting). UV curing is then applied. Microlenses with FOVs up to 90 degrees are fabricated for high-density integration above a CMOS imaging sensor for wide-FOV operation in emerging OWC and OWL applications. Both theoretical ray-tracing analyses and experimental imaging results are presented with good agreement.

关键词： electro-dispensing field-of-view imaging sensor microlens optical wireless numerical aperture

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The multichannel spectral device with transmitting analyzed optical signals by the optical fiber for the liquid propellant rocket engine diagnostics

The multichannel spectral device with transmitting analyzed ...

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Conference on current developments in Lens design and optical engineering XIV

作者： Vaganov, Mikhail A. Moskaletz, Oleg D. St Petersburg State Univ Aerosp Instrumentat Dept Elect & Opt Commun St Petersburg 190000 Russia

ISBN: (纸本)9780819496911

Recently spectroscopic methods of diagnostics of the liquid propellant rocket engines for prevention of emergencies become topical. Such diagnostics is based on tracking appearance of spectral lines of engine's constructional materials in spectrum of rocket plume radiation and glow dynamics of these lines. The multichannel optical spectral device considered in this paper makes the contactless spectrum analysis of optical radiations that allows to use this spectral device for diagnostics of the liquid propellant rocket engines. The novelty of this spectral device lies in application of the fiber-optical bundle and N parallel channels of the spectrum analysis [1]. Each channel contains the narrow-band optical filtration which has been set on the certain wave length. The fiber-optical bundle is used for transmitting analyzed optical radiation on a safe distance for the device from the rocket engine. This method of the contactless rocket engine diagnostics allows to except a direct contact of the spectral device with the field of rocket blast radiation and to eliminate negative influence of the engine on the spectral device, for example the acoustic impact.

关键词： Diagnostics of the rocket engines spectroscopic methods liquid propellant rocket engine spectrum of rocket plume radiation multichannel spectral device contactless spectrum analysis fiber-optical bundle narrow-band optical filter

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Recent developments in Magneto-optic Garnet-type Thin-film Materials Synthesis

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Procedia engineering 2014年 76卷 61-73页

作者： Mohammad Nur-E-Alam Mikhail Vasiliev Viacheslav Kotov Kamal Alameh Electron Science Research Institute Edith Cowan University 270 Joondalup Drive Joondalup WA 6027 Australia Institute of Radio Engineering and Electronics RAS 11 Mohovaya St Moscow 125009 Russia

Magneto-optic (MO) garnets are used in a range of applications in nanophotonics, integrated optics, communications and imaging. Bi-substituted iron garnets of different compositions are the most useful class of materials in applied magneto- optics due to their excellent MO properties (large Faraday effect) and record-high MO figure of merit among all semi- transparent dielectrics. It is highly desirable to synthesise garnets which possess simultaneously a high MO figure of merit and large uniaxial magnetic anisotropy. However, the simultaneous optimization of several material properties and parameters can be difficult in single-layer garnet thin films, and it is also challenging to prepare films with high bismuth content using physical vapor deposition technologies. To meet the current challenge of developing next-generation functional MO materials, we design, develop and demonstrate the functionality of new magnetostatically-altered all-garnet multilayer heterostructures using two different garnet materials of dissimilar anisotropy types (out-of-plane and almost-in- plane). The multilayer structures possess simultaneously a high MO figure of merit and large uniaxial magnetic anisotropy together with low coercivity, if each of the layers is optimized in composition and annealed correctly. We prepare thin-film heterostructures by sandwiching a MO garnet layer with almost in-plane magnetization in-between two MO garnet layers with out-of-plane magnetization using RF sputtering. We apply customised high-temperature oven annealing processes (optimized in temperature and process durations after running many trials) for the as-deposited (amorphous) garnet multilayers to obtain the crystalline garnet phase in every layer. These structures then possess simultaneously a high optical/MO quality and low coercivity, which is very attractive for the development of magnetic photonic crystals, sensing devices and ultra-fast switches. Based on Bi-substituted ferrite garnets grown o

关键词： MO garnets nanocomposites co-sputtering multilayer heterostructures nanophotonics integrated optics magneto-photonic crystals magneto-plasmonic crystals.

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optical Architecture of the new generation Infrared Atmospheric Sounder Interferometer (IASI-NG)

Optical Architecture of the new generation Infrared Atmosphe...

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Conference on current developments in Lens design and optical engineering XIV

作者： Luitot, Clement Boyadjian, Joel Buil, Christian Pasternak, Frederick Ctr Natl Etud Spatiales 18 Ave Edouard Belin F-31401 Toulouse France Astrium SAS F-31402 Toulouse France

ISBN: (纸本)9780819496911

The Infrared Atmospheric Sounder Interferometer (IASI) is a Fourier Transform Spectrometer (FTS) working in the [3.6 mu m, 15.5 mu m] range, dedicated to Numerical Weather Prediction (NWP), atmospheric chemistry and climate monitoring. The second flight model (2 out of 3) is now in orbit and operational, as a payload of the MetOp-B satellite. A new generation of instrument (IASI-NG) to continue the IASI mission with increased performances is currently investigated by the French Space Agency (CNES). The performance objective is mainly a spectral resolution and a radiometric error divided by two compared with the IASI ones. Many different concepts of FTS were studied to try to fulfill these challenging requirements. This paper presents the different envisaged optical architecture and associated trade off. The major issue of the concept is to manage the so-called self-apodization of the interferogram and the associated degradation of the spectral resolution induced by the wider Field of View (FoV) and the longer optical Path Difference (OPD). Increasing these two quantities have very constraining consequences on the optical architecture. Another critical point is the control of straylight which is quite severe and which has been taken into account early in the optical design. To assess the performances of the interferometer, different optical models were built combining analytical approach with ray tracing technics. We will describe the impacts of the demanding spectral requirements on the optical components and our analyses based on these models will be presented.

关键词： FTS Interferometer IASI IASI-NG self-apodization straylight

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Ionic polymer metal composite to achieve optical zoom function in a compact camera

Ionic polymer metal composite to achieve optical zoom functi...

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Conference on current developments in Lens design and optical engineering XIV

作者： Chen, Wei-Hsiang Su, Guo-Dung Natl Taiwan Univ Grad Inst Photon & Optoelect Taipei 106 Taiwan

ISBN: (纸本)9780819496911

Nowadays, there are many popular electronic devices consist of optical focus zooming systems. It is the trend to minimize optical systems in portable devices. For this purpose, we used deformable mirrors in optical systems that can make them thinner and lighter. The Ionic-Polymer Metal Composite (IPMC) is the critical component in our design of the deformable mirror. It has good bending feature and can be driven at low voltage (less than 5 volts). The IPMC fabrication processes contain three steps: acid clean, initial compositing process and surface electrode plating process. After the IPMC is completed, we coated the PDMS on the surface to improve the surface roughness. Then we deposit silver on one side as a reflective surface to finish our deformable mirror. Some characteristics of the IPMC deformable mirror would be demonstrated in the paper. By coating the PDMS on the IPMC surface, the surface roughness can be reduced to about 20 nm. The reflection of the silver layer is up to 90%. In our design, we make the reflective optical zoom module which consists of three biconic mirrors and two deformable mirrors. When we applied voltages on deformable mirrors, the reflective light is successfully focused after the deformation of elliptic IPMC. The zoom ratio of this module can be expected to 1.8 times. The deformable mirror can be changed from flat to 65 diopters (m(-1)) by about 3 volts.

关键词： ionic polymer metal composite (IPMC) polydimethyl siloxane (PDMS) deformable mirror

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A Q-band frequency synthesizer in 0.13 μM SiGe BiCMOS

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Progress In Electromagnetics Research C 2014年 47卷 19-28页

作者： Li, Jiankang Xiong, Yong-Zhong He, Jin Wu, Wen The Ministerial Key Laboratory of JGMT School of Electronic and Optical Engineering Nanjing University of Science and Technology Nanjing 210094 China Terahertz Research Center CAEP Chengdu 611731 China School of Physics and Technology Wuhan University Wuhan 430072 China

In this paper, a 42 GHz frequency synthesizer fabricated with 0.13 μm SiGe BiCMOS technology is presented, which consists of an integer-N fourth-order type-ii phase locked loop (PLL) with a LC tank VCO and a frequency doubler. The core PLL has three-stage current mode logic(CML) and five stage true single phase clock (TSPC) logic in the frequency divider. Meanwhile, a novel balanced common-base structure is used in the frequency doubler design to widen the bandwidth and improve the fundamental rejection. The doubler shows a 41% fractional 3 dB bandwidths with a fundamental rejection better than 25.7 dB. The synthesizer has a maximum output power of 0 dBm with a DC power consumption of 60 mW. The worst phase noise at 100 kHz, 1 MHz and 10 MHz offset frequencies from the carrier is -71 dBc/Hz, -83 dBc/Hz and -102.4 dBc/Hz, respectively.

关键词： Frequency synthesizers

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design of Wearable Binoculars with On-Demand Zoom

Design of Wearable Binoculars with On-Demand Zoom

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Conference on current developments in Lens design and optical engineering XIV

作者： Boye, Robert R. Goeke, Ronald S. Hunt, Jeffery P. Ison, Aaron M. Jared, Bradley H. Pillars, Jamin R. Saavedra, Michael P. Sweatt, William C. Yelton, W. Graham Winrow, Edward G. Wolfley, Steve L. Sandia Natl Labs Albuquerque NM 87185 USA

ISBN: (纸本)9780819496911

Sandia has developed an optical design for wearable binoculars utilizing freeform surfaces and switchable mirrors. The goals of the effort included a design lightweight enough to be worn by the user while providing a useful field of view and magnification as well as non-mechanical switching between normal and zoomed vision. Sandia's approach is a four mirror, off-axis system taking advantage of the weight savings and chromatic performance of a reflective system. The system incorporates an electrochromic mirror on the final surface before the eye allowing the user to switch between viewing modes. Results from a prototype of a monocular version with 6.6x magnification will be presented. The individual mirrors, including three off-axis aspheres and one true freeform, were fabricated using a diamond-turning based process. A slow-slide servo process was used for the freeform element. Surface roughness and form measurement of the freeform mirror will be presented as well as the expected impact on performance. The alignment and assembly procedure will be reviewed as well as the measured optical performance of the prototype. In parallel to the optical design work, development of an electrochromic mirror has provided a working device with faster switching than current state of the art. Switchable absorbers have been demonstrated with switching times less than 0.5 seconds. The deposition process and characterization of these devices will be presented. Finally, details of an updated optical design with additional freeform surfaces will be presented as well as plans for integrating the electrochromic mirror into the system.

关键词： Freeform optics Head-mounted optics Diamond-turning Reflective optics Electrochromic Switchable mirror

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Application of the light field for a simulation to evaluate the MTF of optical lens systems using rendering

Application of the light field for a simulation to evaluate ...

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Conference on current developments in Lens design and optical engineering XIV

作者： Horiuchi, Shuma Yamamoto, Manabu Tokyo Univ Sci Dept Appl Elect Katsushika Ku Tokyo 1258585 Japan

ISBN: (纸本)9780819496911

The modulation transfer function (MTF) in lens systems can be simulated using rendering. Here, the MTF is obtained by rendering test charts with bar target patterns after they are passed through an optical imaging system. The benefit of this method is that it can be applied to shift-variant systems, to which it is difficult to apply the point spread function (PSF), and that it enables the comparison of theoretical results to experimental results when test charts are imaged through an optical imaging system. However, the number of sampled rays must be increased to suppress the variance in the resulting radiance distribution, and the computation time increases proportionally with the number of analyzed spatial frequencies. This report proposes the recording of the light field of light rays, which is a function describing light rays at the entrance pupil. Focused images are compiled for each test chart based on the recorded light field. The time necessary for compilation is significantly shorter than for ray tracing in a lens;therefore, the radiance distribution can be rapidly obtained when the spatial frequency is changed. The methodology to record the light field and the data format are outlined in this report.

关键词： rendering light field modulation transfer function imaging optics

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