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current developments in Lens design and optical engineering XViii 2017

ISBN: (纸本)9781510612075

The proceedings contain 35 papers. The topics discussed include: wavefront analysis from its slope data;parametric diffraction efficiency of non-paraxial sinusoidal reflection gratings;camera system MTF: combining optic with detector;diffraction and geometrical optical transfer functions: calculation time comparison;linear decomposition of the optical transfer function for annular pupils;assembly of a micro-optical resonator based on silicon micro mirrors for use in gyroscopes;and fabrication of multi-focal microlens array on curved surface for wideangle camera module.

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Comparison and analysis of accuracy of elevation extraction based on the ZY-3 01 and 02 Satellites stereoscopic images

Comparison and analysis of accuracy of elevation extraction ...

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2018 ISPRS TC iii Mid-Term Symposium on developments, Technologies and Applications in Remote Sensing

作者： Zhao, Liping Fu, Xingke Dou, Xianhui Liu, Hui Fang, Zhi Satellite Surveying and Mapping Application Center National Administration of Surveying Mapping and Geoinformation Beijing100048 China Sichuan Second Institute of Surveying and Mapping Geographic Information Engineering Chengdu610100 China

The ZY-3 is the civil high-resolution optical stereoscopic mapping satellite independently developed by China. The ZY-3 constellation of the twin satellites operates in a sun-synchronous, near-polar, circular 505 km orbit, with a descending location time of 10: 30 AM and a 29-day revisiting period. The panchromatic triplet sensors, pointing forward, nadir, and backward with an angle of 22°, have excellent base-to-height ratio, which is beneficial to the extraction of DEM. In order to extract more detailed and high-precision DEM, the ZY-3 (02) satellite has been upgraded based on the ZY-3 (01), and the GSD of the stereo camera has been optimized from 3.5 to 2.5 meters. In the paper case studies using the ZY-3 01 and the 02 satellite data for block adjustment and DEM extraction have been carried out in Liaoning Province of China. The results show that the planimetric and altimetric accuracy can reach 3 meters, which meet the mapping requirements of 1: 50,000 national topographic map and the design performance of the satellites. The normalized elevation accuracy index (NEAI) is adopted to evaluate the twin satellite stereoscopic performance, and the NEAIs of the twin ZY-3 satellites are good and the index of the ZY-3(02) is slightly better. The comparison of the overlapping DEMs from the twin ZY-3 satellites and SRTM is analysed. The bias and the standard deviation of all the DEMs are better than 5 meters. In addition, in the process of accuracy comparison, some gross errors of the DEM can be identified, and some elevation changes of the DEM can also be found. The differential DEM becomes a new tool and application. © Authors 2018. CC BY 4.0 License.

关键词： Satellites

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Contact lens design with slope-constrained Q-type aspheres for myopia correction 18

Contact lens design with slope-constrained Q-type aspheres f...

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Conference on current developments in Lens design and optical engineering XViii

作者： Peng, Wei-Jei Cheng, Yuan-Chieh Hsu, Wei-Yao Yu, Zong-Ru Ho, Cheng-Fang Abou-El-Hossein, Khaled Natl Appl Res Labs Instrument Technol Res Ctr Taiwan 20R&D Rd 6Hsinchu Sci Pk Hsinchu 300 Taiwan Nelson Mandela Metropolitan Univ Precis Engn Lab ZA-6031 Port Elizabeth South Africa

ISBN: (纸本)9781510612082;9781510612075

The design of the rigid contact lens (CL) with slope-constrained Q-type aspheres for myopia correction is presented in this paper. The spherical CL is the most common type for myopia correction, however the spherical aberration (SA) caused from the pupil dilation in dark leads to the degradation of visual acuity which cannot be corrected by spherical surface. The spherical and aspheric CLs are designed respectively based on Liou's schematic eye model, and the criterion is the modulation transfer function (MTF) at the frequency of 100 line pair per mm, which corresponds to the normal vision of one arc-minute. After optimization, the MTF of the aspheric design is superior to that of the spherical design, because the aspheric surface corrects the SA for improving the visual acuity in dark. For avoiding the scratch caused from the contact profilometer, the aspheric surface is designed to match the measurability of the interferometer. The Q-type aspheric surface is employed to constrain the root-mean-square (rms) slope of the departure from a best-fit sphere directly, because the fringe density is limited by the interferometer. The maximum sag departure from a best-fit sphere is also controlled according to the measurability of the aspheric stitching interferometer (ASI). The inflection point is removed during optimization for measurability and appearance. In this study, the aspheric CL is successfully designed with Q-type aspheres for the measurability of the interferometer. It not only corrects the myopia but also eliminates the SA for improving the visual acuity in dark based on the schematic eye model.

关键词： aspheric contact lens Q-type aspheres myopia spherical aberration schematic eye model visual acuity best-fit sphere

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Multi-band filter design with less total film thickness for short-wave infrared 18

Multi-band filter design with less total film thickness for ...

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Conference on current developments in Lens design and optical engineering XViii

作者： Yan, Yung-Jhe Chien, I-Pen Chen, Po-Han Chen, Sheng-Hui Tsai, Yi-Chun Ou-Yang, Mang Natl Chiao Tung Univ Dept Elect & Comp Engn Hsinchu Taiwan Natl Cent Univ Dept Opt & Photon Taoyuan Taiwan

ISBN: (纸本)9781510612082;9781510612075

A multi-band pass filter array was proposed and designed for short wave infrared applications. The central wavelength of the multi-band pass filters are located about 905 nm, 950 nm, 1055 nm and 1550 nm. In the simulation of an optical interference band pass filter, high spectrum performance (high transmittance ratio between the pass band and stop band) relies on (1) the index gap between the selected high/low-index film materials, with a larger gap correlated to higher performance, and (2) sufficient repeated periods of high/low-index thin-film layers. When determining high and low refractive index materials, spectrum performance was improved by increasing repeated periods. Consequently, the total film thickness increases rapidly. In some cases, a thick total film thickness is difficult to process in practice, especially when incorporating photolithography liftoff. Actually the maximal thickness of the photoresist being able to liftoff will bound the total film thickness of the band pass filter. For the application of the short wave infrared with the wavelength range from 900nm to 1700nm, silicone was chosen as a high refractive index material. Different from other dielectric materials used in the visible range, silicone has a higher absorptance in the visible range opposite to higher transmission in the short wave infrared. In other words, designing band pass filters based on silicone as a high refractive index material film could not obtain a better spectrum performance than conventional high index materials like TiO2 or Ta2O5, but also its material cost would reduce about half compared to the total film thickness with the conventional material TiO2. Through the simulation and several experimental trials, the total film thickness below 4 um was practicable and reasonable. The fabrication of the filters was employed a dual electric gun deposition system with ion assisted deposition after the lithography process. Repeating four times of lithography and deposition p

关键词： optical interference filter Photolithography Bandpass filter Short-wave infrared

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A Review on Organic-Inorganic Halide Perovskite Photodetectors: Device engineering and Fundamental Physics

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ADVANCED MATERIALS 2017年第41期29卷 2017 Nov;29(41)页

作者： Ahmadi, Mahshid Wu, Ting Hu, Bin Univ Tennessee Dept Mat Sci & Engn Joint Inst Adv Mat Knoxville TN 37996 USA Beijing Jiaotong Univ Coll Sci Beijing 100044 Peoples R China

The last eight years (2009-2017) have seen an explosive growth of interest in organic-inorganic halide perovskites in the research communities of photovoltaics and light-emitting diodes. In addition, recent advancements have demonstrated that this type of perovskite has a great potential in the technology of light-signal detection with a comparable performance to commercially available crystalline Si and iii-V photodetectors. The contemporary growth of state-of-the-art multifunctional perovskites in the field of light-signal detection has benefited from its outstanding intrinsic optoelectronic properties, including photoinduced polarization, high drift mobilities, and effective charge collection, which are excellent for this application. Photoactive perovskite semiconductors combine effective light absorption, allowing detection of a wide range of electromagnetic waves from ultraviolet and visible, to the near-infrared region, with low-cost solution processability and good photon yield. This class of semiconductor might empower breakthrough photodetector technology in the field of imaging, optical communications, and biomedical sensing. Therefore, here, the focus is specifically on the critical understanding of materials synthesis, design, and engineering for the next-stage development of perovskite photodetectors and highlighting the current challenges in the field, which need to be further studied in the future.

关键词： dark current detectivity organic-inorganic halide perovskites photodetectors solution processable

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COMPARISON AND ANALYSIS OF ACCURACY OF ELEVATION EXTRACTION BASED ON THE ZY-3 01 AND 02 SATELLITES STEREOSCOPIC IMAGES

COMPARISON AND ANALYSIS OF ACCURACY OF ELEVATION EXTRACTION ...

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The ISPRS Technical Commission iii Midterm Symposium on "developments, Technologies and Applications in Remote Sensing"

作者： Liping Zhao Xingke Fu Xianhui Dou Hui Liu Zhi Fang Satellite Surveying and Mapping Application Center National Administration of SurveyingMapping and Geoinformation Sichuan Second Institute of Surveying and Mapping Geographic Information Engineering

The ZY-3 is the civil high-resolution optical stereoscopic mapping satellite independently developed by China. The ZY-3 constellation of the twin satellites operates in a sun-synchronous, near-polar, circular 505 km orbit, with a descending location time of 10:30 AM and a 29-day revisiting period. The panchromatic triplet sensors, pointing forward, nadir, and backward with an angle of 22 °, have excellent base-to-height ratio, which is beneficial to the extraction of DEM. In order to extract more detailed and highprecision DEM, the ZY-3(02) satellite has been upgraded based on the ZY-3(01), and the GSD of the stereo camera has been optimized from 3.5 to 2.5 meters. In the paper case studies using the ZY-3 01 and the 02 satellite data for block adjustment and DEM extraction have been carried out in Liaoning Province of China. The results show that the planimetric and altimetric accuracy can reach 3 meters, which meet the mapping requirements of 1:50,000 national topographic map and the design performance of the satellites. The normalized elevation accuracy index(NEAI) is adopted to evaluate the twin satellite stereoscopic performance, and the NEAIs of the twin ZY-3 satellites are good and the index of the ZY-3(02) is slightly better. The comparison of the overlapping DEMs from the twin ZY-3 satellites and SRTM is analysed. The bias and the standard deviation of all the DEMs are better than 5 meters. In addition, in the process of accuracy comparison, some gross errors of the DEM can be identified, and some elevation changes of the DEM can also be found. The differential DEM becomes a new tool and application.

关键词： ZY-3 Stereoscopic Satellite GSD DEM differential DEM Accuracy

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Heterogeneous Silicon iii-V Mode-Locked Lasers. 1

Heterogeneous Silicon III-V Mode-Locked Lasers. 1

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作者： Davenport, Michael Loehrlein.0 University of California Santa Barbara.bElectrical & Computer Engineering.0

学位级别：Ph.D.

Mode-locked lasers are useful for a variety of applications, such as sensing, telecommunication, and surgical instruments. This work focuses on integrated-circuit mode-locked lasers: those that combine multiple optical and electronic functions and are manufactured together on a single chip. While this allows production at high volume and lower cost, the true potential of integration is to open applications for mode-locked laser diodes where solid state lasers cannot fit, either due to size and power consumption constraints, or where small optical or electrical paths are needed for high bandwidth. Unfortunately, most high power and highly stable mode-locked laser diode demonstrations in scientific literature are based on the Fabry-Perot resonator design, with cleaved mirrors, and are unsuitable for use in integrated circuits because of the difficulty of producing integrated Fabry-Perot cavities. We use silicon photonics and heterogeneous integration with iii-V gain material to produce the most powerful and lowest noise fully integrated mode-locked laser diode in the 20 GHz frequency range. If low noise and high peak power are required, it is arguably the best performing fully integrated mode-locked laser ever demonstrated. We present the design methodology and experimental pathway to realize a fully integrated mode-locked laser diode. The construction of the device, beginning with the selection of an integration platform, and proceeding through the fabrication process to final optimization, is presented in detail. The dependence of mode-locked laser performance on a wide variety of design parameters is presented. Applications for integrated circuit mode-locked lasers are also discussed, as well as proposed methods for using integration to improve mode-locking performance to beyond the current state of the art.

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optical MEMS for earth observation

Optical MEMS for earth observation

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International Conference on Space Optics 2012, ICSO 2012

作者： Liotard, Arnaud Viard, Thierry Noell, Wilfried Zamkotsian, Frédéric Freire, Marco Guldimann, Benedikt Kraft, Stefan Thales Alenia Space Cannes-la-Bocca France EPFL SAMLAB Neuchâtel Switzerland Marseille France ESA – ESTEC Noordwijk Netherlands

ISBN: (纸本)9781510616172

Due to the relatively large number of optical Earth Observation missions at ESA, this area is interesting for new space technology developments. In addition to their compactness, scalability and specific task customization, optical MEMS could generate new functions not available with current technologies and are thus candidates for the design of future space instruments. Most mature components for space applications are the digital mirror arrays, the micro-deformable mirrors, the programmable micro diffraction gratings and tiltable micromirrors. A first selection of market-pull and techno-push concepts is done. In addition, some concepts are coming from outside Earth Observation. Finally two concepts are more deeply analyzed. The first concept is a programmable slit for straylight control for space spectro-imagers. This instrument is a push-broom spectro-imager for which some images cannot be exploited because of bright sources in the field-of-view. The proposed concept consists in replacing the current entrance spectrometer slit by an active row of micro-mirrors. The MEMS will permit to dynamically remove the bright sources and then to obtain a field-of-view with an optically enhanced signal-to-noise ratio. The second concept is a push-broom imager for which the acquired spectrum can be tuned by optical MEMS. This system is composed of two diffractive elements and a digital mirror array. The first diffractive element spreads the spectrum. A micromirror array is set at the location of the spectral focal plane. By putting the micro-mirrors ON or OFF, we can select parts of field-of-view or spectrum. The second diffractive element then recombines the light on a push-broom detector. Dichroics filters, strip filter, band-pass filter could be replaced by a unique instrument. © 2012 ESA and CNES.

关键词： Bandpass filters

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Technological developments for ultra-lightweight, large aperture, deployable mirror for space telescopes

Technological developments for ultra-lightweight, large aper...

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International Conference on Space Optics 2010, ICSO 2010

作者： Zuccaro Marchi, Alessandro D'Amato, Francesco Gallieni, Daniele Biasi, Roberto Molina, Marco Duò, Fabrizio Ruder, Nikolaus Salinari, Piero Lisi, Franco Riccardi, Armando Gambicorti, Lisa Simonetti, Francesca Pereira Do Carmo, Joao Pedro N. Largo Enrico Fermi 6 Firenze50125 Italy 23868 Italy Microgate Srl Via Stradivari 4 Bolzano Italy via Gallarate 15 Milano20151 Italy INAF- Arcetri Astrophysics Observatory Largo Enrico Fermi 5 Firenze50125 Italy ESA - ESTEC Keplerlaan 1 Noordwijk2200 AG Netherlands

ISBN: (纸本)9781510616196

The increasing interest on space telescopes for scientific applications leads to implement the manufacturing technology of the most critical element, i.e. the primary mirror: being more suitable a large aperture, it must be lightweight and deployable. The presented topic was originally addressed to a spaceborne DIAL (Differential Absorption LIDAR) mission operating at 935.5 nm for the measurement of water vapour profile in atmosphere, whose results were presented at ICSO 2006 and 2008. Aim of this paper is to present the latest developments on the main issues related to the fabrication of a breadboard, covering two project critical areas identified during the preliminary studies: the design and performances of the long-stroke actuators used to implement the mirror active control and the mirror survivability to launch via Electrostatic Locking (EL) between mirror and backplane. The described work is developed under the ESA/ESTEC contract No. 22321/09/NL/RA. The lightweight mirror is structured as a central sector surrounded by petals, all of them actively controlled to reach the specified shape after initial deployment and then maintained within specs for the entire mission duration. The presented study concerns: a) testing the Carbon Fiber Reinforced Plastic (CFRP) backplane manufacturing and EL techniques, with production of suitable specimens;b) actuator design optimisation;c) design of the deployment mechanism including a high precision latch;d) the fabrication of thin mirrors mock-ups to validate the fabrication procedure for the large shells. The current activity aims to the construction of an optical breadboard capable of demonstrating the achievement of all these coupled critical aspects: optical quality of the thin shell mirror surface, actuators performances and back-plane - EL subsystem functionality. © Copyright SPIE.

关键词： Mirrors

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Space optical instruments design optimisation thanks to CMOS image sensor technology 6

Space optical instruments design optimisation thanks to CMOS...

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6th International Conference on Space Optics, ICSO 2006

作者： Saint-Pe, Olivier Tulet, Michel Davancens, Robert Larnaudie, Franck Bréart De Boisanger, Michel Magnan, Pierre Martin-Gonthier, Philippe Corbière, Franck Estribeau, Magali EADS Astrium 31 Avenue des Cosmonautes Toulouse Cédex 431402 France SUPAERO-CIMI 10 Avenue Edouard Belin Toulouse Cédex31055 France

ISBN: (纸本)9781510616233

Today, both CCD and CMOS sensors can be envisaged for nearly all visible sensors and instruments designed for space needs. Indeed, detectors built with both technologies allow excellent electro-optics (EO) performances to be reached, the selection of the most adequate device being driven by their functional and technological features and limits. The first part of the paper shortly recalls how far CMOS Image Sensors (CIS) EO performances have been improved these last years. The second part reviews the advantages of CMOS technology for space applications, illustrated by examples of CIS developments performed by EADS Astrium and Supaéro/CIMI for current and short term coming space programs. © COPYRIGHT SPIE. Downloading of the abstract is permitted for personal use only.

关键词： Space applications

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