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Conference on current developments in Lens design and optical engineering XVI

作者： Mahajan, Virendra N. Antonio Diaz, Jose Univ Arizona Coll Opt Sci Tucson AZ 85721 USA Univ Granada Dept Opt E-18071 Granada Spain

ISBN: (纸本)9781628417449

The geometrical and diffraction point-spread functions of an optical imaging system have been reviewed and compared in the past [V. N. Mahajan, "Comparison of geometrical and diffraction point-spread functions," SPIE Proc. 3729, 434-445 (1999)]. In this paper, we review and compare its corresponding optical transfer functions. While the truth lies with the diffraction OTF, it is considered easier and quicker to calculate the geometrical Oil, especially for large aberrations. We briefly describe the theory of the two OTFs, and explore the range of spatial frequencies and the magnitude of the primary aberrations over which the geometrical OTF may provide a reasonable approximation of the diffraction OTF.

关键词： optical transfer functions Monochromatic aberrations Spatial frequencies Diffraction Actinium Imaging systems Geometrical optics optical imaging Modulation transfer functions Fourier transforms

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Testing and alignment of freeform based multi-mirror telescopes 16

Testing and alignment of freeform based multi-mirror telesco...

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Conference on current developments in Lens design and optical engineering XVI

作者： Zhang, Xue-jun Hu, Hai-xiang Xue, Dong-lin Li, Ming Chinese Acad Sci Changchun Inst Opt & Fine Mech & Phys Changchun 130033 Jilin Peoples R China Univ Chinese Acad Sci Beijing 100049 Peoples R China

ISBN: (纸本)9781628417449

Three Mirror Anastigmat (TMA) systems including both on-axis and off-axis configurations have been widely used in space applications. In some designs, to correct for high order aberrations and realize large FOV, freeform surfaces are used to provide more design freedoms. This trend brings challenges to optical manufacturing and testing community Since testing is critical to make high accurate aspheres and freeform surfaces, the paper addressed Computer Generated Hologram (CGH) design and implement to measure large freeform mirrors. In particular, CGH assisted alignment procedure for TMA telescopes were discussed in detail.

关键词： TMA freeform mirror CGH testing optical alignment

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Analytical modeling and numerical simulation of the short-wave infrared electron-injection detectors

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APPLIED PHYSICS LETTERS 2016年第12期108卷 121102-121102页

作者： Movassaghi, Yashar Fathipour, Vala Fathipour, Morteza Mohseni, Hooman Univ Tehran Dept Elect & Comp Engn Modeling & Simulat Semicond Devices Lab Tehran *** Iran Northwestern Univ Bioinspired Sensors & Optoelect Lab 2145 Sheridan Rd Evanston IL 60208 USA

This paper describes comprehensive analytical and simulation models for the design and optimization of the electron-injection based detectors. The electron-injection detectors evaluated here operate in the short-wave infrared range and utilize a type-ii band alignment in InP/GaAsSb/InGaAs material system. The unique geometry of detectors along with an inherent negative-feedback mechanism in the device allows for achieving high internal avalanche-free amplifications without any excess noise. Physics-based closed-form analytical models are derived for the detector rise time and dark current. Our optical gain model takes into account the drop in the optical gain at high optical power levels. Furthermore, numerical simulation studies of the electrical characteristics of the device show good agreement with our analytical models as well experimental data. Performance comparison between devices with different injector sizes shows that enhancement in the gain and speed is anticipated by reducing the injector size. Sensitivity analysis for the key detector parameters shows the relative importance of each parameter. The results of this study may provide useful information and guidelines for development of future electron-injection based detectors as well as other heterojunction photodetectors. (C) 2016 AIP Publishing LLC.

关键词： Dark currents iiI-V semiconductors Infrared detectors Numerical modeling optical sensors

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Integration design of rigid endoscope with different viewing angles 16

Integration design of rigid endoscope with different viewing...

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Conference on current developments in Lens design and optical engineering XVI

作者： Zhang, Lingyun Cheng, Dewen Wang, Yongtian Beijing Inst Technol Sch Informat Sci & Technol Dept Optoelect Engn Beijing 100081 Peoples R China

ISBN: (纸本)9781628417449

High definition and magnification rigid endoscope is a significant equipment in the examination and surgery. In this paper, the design of a high definition (HD) rigid endoscope with zero viewing direction is presented with a FOV of 70. The entrance pupil is 0.3 mm, achieved for the first time to our best knowledge. For the fabricated prototype, the theoretical resolution is 22.3 lp/mm at an object distance of 20 mm, and the depth of field (DOF) is 115 mm The performance is proved to be great for observation during diagnosis and surgery. Besides, the endoscope with non-zero viewing direction is more needful in some conditions such as observing and diagnosing lesions on inner walls of organs and tissues. In this paper, we present two designs with non-zero viewing direction for better applications.

关键词： optical design rigid endoscope high definition depth of field stray light

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Landsat-swath Imaging Spectrometer design 16

Landsat-swath Imaging Spectrometer Design

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Conference on current developments in Lens design and optical engineering XVI

作者： Mouroulis, Pantazis Green, Robert O. Van Gorp, Byron Moore, Lori Wilson, Daniel W. Bender, Holly A. CALTECH Jet Prop Lab Pasadena CA 91109 USA

ISBN: (纸本)9781628417449

We describe the design of a high-throughput pushbroom imaging spectrometer and telescope system that is capable of Landsat swath and resolution while providing better than 10 nm per pixel spectral resolution. The design is based on a 3200 x 480 element x 18 mu m pixel size focal plane array, two of which are utilized to cover the full swath. At an optical speed of F/1.8, the system is the fastest proposed to date to our knowledge. The utilization of only two spectrometer modules fed from the same telescope reduces system complexity while providing a solution within achievable detector technology. Predictions of complete system response are shown. Also, it is shown that detailed ghost analysis is a requirement for this type of spectrometer and forms an essential part of a complete design.

关键词： Imaging spectrometer Landsat Dyson spectrometer

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optical model of optical volume diffusion plate - BSDF measurement of polycarbonate plate doped with silicon dioxide micro particle 16

Optical model of optical volume diffusion plate - BSDF measu...

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Conference on current developments in Lens design and optical engineering XVI

作者： Lin, Che-Chu Yu, Yeh-Wei Chen, Yu-Heng Le, Ming Sun, Ching-Cherng Chen, Jong-Wu Cheng, Chih-Yuan Natl Cent Univ Dept Opt & Photon Chungli 320 Taiwan Plast Ind Dev Ctr Taichung 407 Taiwan

ISBN: (纸本)9781628417449

High-efficiency diffusers play important roles in modern optical industry. The applications include back-light of television, uniform lighting, glare suppression, lighting decoration, and so on. In this paper, we develop optical volume diffusion plate using polycarbonate (PC) plate doped with silicon dioxide (SiO2) micro particle. The scattering distribution of diffusers is an important factor in the lighting design. Commercial detectors often measure the bidirectional scattering distribution function (BSDF) by a scanning and time-consuming method. We have proposed screen imaging synthesis (SIS) system in 2012, and it can easily measure the bidirectional transmittance distribution function (BTDF). In this paper, the optimized formula is presented to correct the vignetting effect and scattering effect caused by the screen. A quasi-Lambertian screen is made to enhance precision. Finally, we combine the SIS system with the rotation controller, and a semi-automatic measuring machine is built. The SIS generation can measure BSDF of the samples precisely and easily. In order to reduce glare problems and design a luminaire with uniform light distribution, we usually use diffusers to modulate the luminaire

关键词： BSDF BTDF BRDF Image reconstruction techniques

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design considerations for an unconventional infrared prism with a 90 degree ray deviation 16

Design considerations for an unconventional infrared prism w...

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Conference on current developments in Lens design and optical engineering XVI

作者： Akarca, Beyza Artan, Goktug Gencehan TUBITAK SAGE Ankara Turkey

ISBN: (纸本)9781628417449

In this study, the optical performance of a 90 degree prism working in the mid-wave infrared region with the purpose of carrying a beam of light from one optical system to another in an unconventional way is discussed. First, a group of mirrors is considered as a design alternative to lower the overall cost of the system. However, using mirrors greatly increases the diameter of the beam due to the rays coming from wide field of view angles. Another drawback of mirrors is that having separate mirrors requires precise alignment for the system to work at full performance which is difficult for the given application. However, these alignment issues are not valid for a single piece prism. Therefore, a single piece prism is the preferred option and has been taken into account in this study. Material selection is important, especially in the mid-wave infrared region where the index of refraction differs greatly from material to material. Silicon and Germanium are the materials preferred because of their high index of refraction and transmission characteristics. Aside from optical properties, these materials are also considered in terms of manufacturability. Also, options for the coatings to be applied to reflecting surfaces of the prism are discussed with regard to the transmission loss within the system. In order to have total internal reflection within a prism, coatings must be chosen carefully to handle transmission loss at the reflecting surfaces. All of the system parameters are examined using sequential and non-sequential modes of ZEMAX OpticStudio software.

关键词： 90 degree prism infrared prism optical design infrared prism

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Ultra-compact hourglass lens for integrated cameras 16

Ultra-compact hourglass lens for integrated cameras

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Conference on current developments in Lens design and optical engineering XVI

作者： Rezaei, Mohsen Nia, Iman Hasani Bonakdar, Alireza Mohseni, Hooman Northwestern Univ Dept Elect Engn & Comp Sci Bioinspired Sensors & Optoelect Lab BISOL Evanston IL 60208 USA

ISBN: (纸本)9781628417449

An ultra-small telecentric lens with sub-millimeter thickness is proposed. This lens with 0.2 numerical aperture and high field of view is a good candidate to be used in multi-aperture super resolution imagers. Point spread function and the telecentricity of the lens is extracted numerically and measured experimentally. The ray-optics simulation results show nearly diffraction limited performance for the lens.

关键词： Cameras Imaging systems Point spread functions Silicon Image sensors Lens design Infrared cameras Modulation transfer functions Super resolution Sensors

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optical Modeling with Precise Spatial-chromatic Light Distribution in Phosphor-converted White LEDs 16

Optical Modeling with Precise Spatial-chromatic Light Distri...

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Conference on current developments in Lens design and optical engineering XVI

作者： Sun, Ching-Cherng Chang, Yu-Yu Wang, Yu-Huan Chen, Ching-Yi Lo, Yi-Chien Cheng, Han-Hsiang Natl Cent Univ Dept Opt & Photon Chungli 320 Taiwan Natl Cent Univ Inst Lighting & Display Chungli 320 Taiwan

ISBN: (纸本)9781628417449

White light LEDs become more and more important in display and lighting in various structures. Here a new modeling algorithm for phosphor-converted white light-emitting diodes (pcW-LEDs) is proposed, aiming to perform accurate simulation for color appearance, where potentially enabling optical designers to remove yellowish/bluish spots in LED lighting. The proposed modeling method is applied to simulate a pcW-LED with a hemi spherical lens. The simulation accurately predicts the blue and yellow light distribution. The model is further verified by applying a total internal reflector lens to the pcW-LED. In the midfield region, the blue and yellow light distribution exhibit large variations as the observation distance changed;this varying light pattern for both the blue and yellow lights can be accurately predicted by using the proposed model. The well-established optical model should facilitate designing a pcW-LED that features high-quality illumination and enhances color uniformity.

关键词： packaging efficiency luminous efficacy white LED phosphor converted

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Fast robust non-sequential optical ray-tracing with implicit algebraic surfaces 16

Fast robust non-sequential optical ray-tracing with implicit...

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Conference on current developments in Lens design and optical engineering XVI

作者： Greynolds, Alan W. 10741 E Placita Metate Tucson AZ 85749 USA

ISBN: (纸本)9781628417449

The fastest, most robust, general technique for non-sequentially ray-tracing a large class of imaging and non-imaging optical systems is by geometric modeling with algebraic (i.e. polynomial) implicit surfaces. The basic theory of these surfaces with special attention to optimizing their precise intersection with a ray (even at grazing incidence) is outlined for an admittedly limited software implementation. On a couple of "tame" examples, a 64-bit Windows 7 version is significantly faster than the fastest commercial design software (all multi-threaded). Non-sequential ray-surface interactions approaching 30M/sec are achieved on a 12-core 2.67 GHz Mac Pro desktop computer. For a more exotic example of a 6th degree Wood's horn beam dump (light trap), a 32-bit Windows single thread version traces rays nearly 4 times faster than the commercial ASAP software's implicit algebraic surface and over 13 times faster than its equivalent NURBS surface. However, implicit surfaces are foreign to most CAD systems and thus unfortunately, don't easily fit into a modern workflow.

关键词： Ray tracing software surface modeling

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