中国科学院机构知识库网格系统: 检索

The research of single point diamond turning Fresnel lens technology 会议论文 OAI收割
Chengdu, China, June 26, 2018 - June 29, 2018
作者: Huang, Yuetian; Fan, Bin; Wan, Yongjian; Li, Shijie

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收藏 | 浏览/下载：20/0 | 提交时间：2021/05/06

Fresnel lens single point diamond turning tool parameters shape precision

Research on mirror surface shape of space camera fitting based on SVD 会议论文 OAI收割
Beijing, China, 2019-07-07
作者: Huang, Tuo; Chen, Rong-Li; Chu, Chang-Bo

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收藏 | 浏览/下载：11/0 | 提交时间：2020/03/04

mirror surface shape Zernike polynomials spherical mirror fitting precision Zernike polynomials terms singular value decomposition

Surface shape optimization for the space membrane reflector (EI CONFERENCE) 会议论文 OAI收割
2011 International Conference on Electronic and Mechanical Engineering and Information Technology, EMEIT 2011, August 12, 2011 - August 14, 2011, Harbin, China
作者: Zhang Y.; Zhang P.

收藏 | 浏览/下载：23/0 | 提交时间：2013/03/25

Space membrane reflector is very promised for optical quality application with the merits of ultra-lightweight and flexible. In order to improve the surface precision of membrane reflectors the formation and surface shape error of a membrane at uniform load are studied based on the henky-cambell equations of circular membrane. The ANSYS software is used to build an optimization model of membrane reflector surface shape in which the yield strength is the state variable the surface load on ten concentric annular regions of the mirror is the design variable and the minimum RMS between ideal surface and mirror surface is the target function. and the theoretical and experimental result show that RMS and PV of the optimized surfaces are reduced respectively than those before optimization. In a word this paper offers the theoretical and experimental basis of the polyimide membrane reflector. 2011 IEEE.

An appraisal method of dynamic interpolation error for high precision encoder (EI CONFERENCE) 会议论文 OAI收割
2011 International Conference on Electronics and Optoelectronics, ICEOE 2011, July 29, 2011 - July 31, 2011, Dalian, China
作者: Wan Q.-H.; Liu C.-X.; Liu C.-X.

收藏 | 浏览/下载：19/0 | 提交时间：2013/03/25

This paper introduces an appraisal method of the dynamic interpolation error for the high precision encoder (Lissajou pattern calculation method). When the encoder is rolling two groups of fine photoelectric signals whose phase difference are /2 can be collected using data collected car. The shape and position deviation can be obtained through the comparison between Lissajou charts and the standard circle. Then dynamic interpolation error can be calculated out directly. This method is immune to the influence of encoder's speed and has no rigid demand to the test circumstances and test devices. The experimental results indicate that this method is feasible and important to the encoder's dynamic interpolation error checking. 2011 IEEE.

The Research of real time auto-recognition of the moire fringe (EI CONFERENCE) 会议论文 OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Imaging Detectors and Applications, May 24, 2011 - May 26, 2011, Beijing, China
Wang M.-J.; Wu Z.-G.

收藏 | 浏览/下载：19/0 | 提交时间：2013/03/25

Measuring the movement of raster by the method of moire fringe has the advantage of high sensitivity high resolution and non-contacted measurement. The characteristic of moire fringe is that the image is white alternate with black the angle of the stripes is uniform the width of the stripes is uniform the terminators of the stripes aren't clear. A fast method that can figure out the width and angle of the moire fringe precisely is put forward in this paper. It calculates the angle the stripes firstly. According to the principle of the minimum mean squared error (MMSE) the closer a series of data is the smaller the value of the MMSE will be. The method is described as follows: It takes the image's center as the origin 180 beelines pass through the origin with the same angle interval. it calculates the value of the minimum mean squared error of the 180 beelines and find out the least one among those then the angle of the moire fringe comes out primarily. In order to improving the calculating precision of moire fringe 60 equal angles are divided in the neighborhood of the angle then a precise angle of moire fringe is calculated according to the principle of the MMSE. After getting out the angle of the moire fringe we begin to calculate the width of moire fringe. A line vertical with the moire fringe is drawn and we can get the width of the moire fringe by the vertical line. In order to get over the influence of the noise an effective area with the shape of diamond is selected in the image. The data of area is accumulated and projected according to the direction of moire fringe and a sine curve come out. The width of moire fringe can be obtained by getting the position of the first wave crest the position of the last wave crest and the number of wave crest. Experiments prove that the precision of the method put forward in this paper is enhanced in comparison with the traditional frequency method the precision of width calculation achieves to 99.6% according to the evaluation indicators of width detection error. The computing speed is boosted largely compared with traditional method and it can achieve with 15 ms that satisfying the demand of real time. 2011 SPIE.

Shape and alignment measurement of the heliostat by laser deflectometry (EI CONFERENCE) 会议论文 OAI收割
Optical Modeling and Measurements for Solar Energy Systems II, August 13, 2008 - August 14, 2008, San Diego, CA, United states
作者: Liu H.; Zhang H.

收藏 | 浏览/下载：16/0 | 提交时间：2013/03/25

In the solar tower thermal power generation system such apparatus and corresponding software packages are developed. With the help of these two apparatus (hexagon) the precision of the slope angle of the heliostat is the major factor the heliostat of 1002 for the 1MWe solar tower power plant in Beijing are measured and connected successfully. which influences the efficiency of the system consisting of 55 mirror facets of 1.8182 m2 consequently this angle should be tested accurately. In this paper the methods based on laser deflectometry are proposed to measure the shape error of the mirror facet and the connected error of the facets

Research on the support structure of the primary mirror of large-aperture telescope (EI CONFERENCE) 会议论文 OAI收割
3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Large Mirrors and Telescopes, July 8, 2007 - July 12, 2007, Chengdu, China
Yang W.; Jingxu Z.

收藏 | 浏览/下载：28/0 | 提交时间：2013/03/25

Large-aperture telescope can be used in surveying battlefield researching landform searching object real-time monitoring imaging detecting and identifying spatial targets and so on. A large-aperture telescope for achieving high resolution power is designed to monitor spatial target and image in real time. Real-time monitoring plays an important role in military conflicts. The orbit parameter of object quantity geometrical shape parameter and so on can be obtained by detect spatial target. With the development of optical technology people require larger aperture in optics-electronic (OE) system. By increasing optical aperture the ability of collecting light and resolution power in the system can be enhanced. But the support structure of the primary mirror of large-aperture telescope will be a very difficult problem. With the increase of primary mirror aperture the weight of the primary mirror will become larger than before. The root mean square (rms) of the primary mirror is affected by many factors such as deadweight deformation of heat environment and so on. Due to the primary mirror of telescope is an important component of telescope system. By reducing the weight of primary mirror precision of the system is ensured. During the designing phase one can consider the supporting project of the primary mirror synthetically and analyze it roundly according to technical requirement of optical system and the effect factors. The final structural design can be reasonable. In an astronomical telescope the surface of reflector is an important part for collecting dark radiation of celestial bodies. Its surface shape will have an effect on collecting efficiency of telescope radiant energy directly. So the rms must be very high. Optical system of large aperture small wavelength and small focus can receive maximal light intensity. For ground-based optical astronomical telescope the design proposed in the paper can satisfy the requirement of the possible minimum atmosphere seeing at astronomical observatory site and exert the use efficiency of the telescope adequately. So the accuracy of the traditional surface of reflector can assure that 90% of all the light energy can be focused on within the angle diameter range of the minimum atmosphere seeing then 100% of light energy should be focused on the angle diameter range of minimum atmosphere seeing. Because the rms of mirror is very high precise surface machining and accurate the support of mirror are very important tasks during designing and manufacturing the telescope. In the paper various support techniques of a large-aperture telescope primary mirror are discussed and a 3.5 meter telescope system at the Starfire Optical Range (SOR) overviewed simply which was operated by the Directed Energy Directorate of the Air Force Research Laboratory Kirtland AFB NM USA from the ground-based O-E system for the observations of spatial target. We also analyze Theoretical elastic deformation of the Steward Observatory 2.3 meter mirror is analyzed.

Geometrical modulation transfer function of different active pixel of CMOS APS (EI CONFERENCE) 会议论文 OAI收割
2nd International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, November 2, 2005 - November 5, 2005, Zian, China
作者: Li J.; Liu J.; Liu J.; Liu J.; Li J.

收藏 | 浏览/下载：26/0 | 提交时间：2013/03/25

The geometrical Modulation Transfer Function (MTF) of CMOS APS (active pixel sensor) is analyzed in this paper. Advanced APS have been designed and fabricated where different pixel shapes such as square rectangle and L shape were placed because the amplifier circuit and other function circuits inter pixel of APS take up some pixel area. MTF is an important figure of merit in focal plane array imaging sensors. Research on analyzing the MTF for the proper pixel shape is currently in progress for a centroidal configuration of a target position. MTF will give us a more complete understanding of the tradeoffs opposed by the different pixel designs and by the signal processing conditions. Based on image sensor sampling and reconstructing model the MTF expression of any active pixel shape has been deduced in this paper. According to actual pixel shape three different active area pixels were analyzed they were square rectangle and L shape their Fill Factor (FF) is 30% 44% and 55% respectively. Results of simulation experiments indicate that different pixel geometrical characteristics contribute significantly to the figures of their MTF. Different geometrical shape of active sensitive area of pixel and different station in pixel would influence MTF figures. The analysis results are important in designing better APS pixel and more important in analyzing imaging system performance of APS subpixel precision system.

Key techniques of laser direct writing of fine lines on the spherical surface (EI CONFERENCE) 会议论文 OAI收割
ICO20: Optical Design and Fabrication, August 21, 2005 - August 26, 2005, Changchun, China
Liang F.; Hu J.

收藏 | 浏览/下载：21/0 | 提交时间：2013/03/25

The main principles of laser direct writing (LDW) system for lines on the spherical surface (SS) are discussed. It is pointed out that line profile is determined by the exposure dose distribution which lies on the light intensity distribution of focus plane and the scanning speed. To improve the quality of line profile on the SS several key techniques as follows are introduced. Firstly the unique system configuration four axes mutually intersecting at the center of the SS is adopted which ensures the shape of the focus be maintained circular during the writing period. Secondly an automatic focus system (AFS) with the function of automatic focus in a certain range is introduced. Thirdly to guarantee the linear velocity to accord with the exposure character of the photoresist all the time an efficient arithmetic that controls motors run at appropriate angular velocity in different latitude is developed. Finally to achieve a stable and well-behaved system so as to compensate the velocity instability resulting from unavoidable errors of mechanical and electronics factor a powerful programmable multi-axis controller (PMAC) is utilized as the kernel element of the servocontrol system and the curves of step response and parabolic response achieved by feedforward and PID loop tuning indicate that the location precision and velocity stability have reached a high level. The experimental results of LDW of lines on the SS work piece with a diameter 30 mm and a radius equal to 100 mm are given. The section analysis of the lines on the photoresist by the atomic force microscope (AFM) after exposure and development is performed. The results show that line width is about 3.0 m and the steep sides of the lines are parallel to each other.

Study on the fabrication of blazed grating with sub-micrometer space on aluminum film (EI CONFERENCE) 会议论文 OAI收割
12th International Manufacturing Conference in China, IMCC2006, September 21, 2006 - September 23, 2006, Xi'an, China
Lun S.; Hao D.; Qi X.

收藏 | 浏览/下载：16/0 | 提交时间：2013/03/25

The saw tooth grooves of blazed grating ruled by ruling engine are formed by diamond tool which presses on the aluminum film evaporated on the substrate of optical glass or metal. The real shape of ruled saw tooth groove is different from that of the ideal groove and the ruling process indicates that there are the zero order planes similar to the flat tops on the grating grooves. The results of Fourier analysis for the real ruled grating featuring the zero order plane structure shows that the flat top width is an important factor for grating efficiency. Additionally bigger pressure value loaded on the diamond tool and bigger lateral pressure value on the aluminum film will be benefit to the improvement of grating diffraction efficiency. Based on the grating interferometer the high precision positioning control system of ruling engine guarantees the accuracy of the grooves space. High density blazed grating whose space is 0.83p.m is manufactured and its' grooves spaces are very equidistant and uniform under the view field of AFM. And the infrared blazed grating whose diffraction efficiency in the first order is up to 97 percent is ruled successfully also.