中国科学院机构知识库网格系统: 检索

Design of the real-time autofocusing system for collimator with long focus length and large aperture (EI CONFERENCE) 会议论文 OAI收割
2011 International Academic Conference on Numbers, Intelligence, Manufacturing Technology and Machinery Automation, MAMT 2011, December 24, 2011 - December 25, 2011, Wuhan, China
作者: Zhang X.; Zhang X.; Zhang X.

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Large aperture collimator which has been widely used for calibrating and testing various optical devices plays an essential role in correlative laboratories. As being the basic testing and calibration equipment the large aperture collimator's accuracy should be much higher than the device under testing in order to ensure the accuracy of the measurement. However the process of adjusting the collimator is extremely complicated due to the collimator's large aperture and long focal length. So it is difficult to ensure the measurement's quality and easy to cause the system being vulnerable to the surrounding environment. One of the most common problems is defocus. In order to solve the problem above this issue presents a new type of autocollimator autofocusing system which uses pentaprism instead of using large-aperture plane mirror semiconductor lasers as light source and CCD sensor as receiver. The system is smaller lighter and more convenient when using. The computer simulation shows that the autofocusing system's resolution could reach the accuracy of 40m. If we use the relevant algorithms to execute the sub-pixel scanning the resolution could reach the accuracy of 10m. It shows that the system could satisfy the required testing precision of testing large aperture optical device.

Study on spectrograph for ionosphere: A broadband imaging instrument prototype for far-ultraviolet (EI CONFERENCE) 会议论文 OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Space Exploration Technologies and Applications, May 24, 2011 - May 26, 2011, Beijing, China
作者: Wang S.-R.; Lin G.-Y.; Yu L.

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Current research on space-based exploration for the ionosphere needs more advanced technologies. Because the spectral signals in the ionosphere distributing basically in the far-ultraviolet waveband are very weak. Usual spectrometer structures and detectors such as CCD can't receive enough information. Based on this principle of atmospheric sounding the imaging spectrometer prototype for ionosphere detection application was designed to solve the problem. This prototype consists of the telescope and the imaging spectrometer. The simple structure and small number of mirrors can help higher transmission efficiency be achieved and weak signals detection be implemented. The telescope is an off-axis parabolic mirror and the spectrometer is a modified Czerny-Turner spectral imaging system. Modified Czerny-Turner spectrometer contains a spherical mirror a fixed plane grating and a toroidal mirror. By adjusting the incident angle to the collimating mirror and using toroidal mirror coma and astigmatism were corrected well. We also optimize distances between the grating to the focusing mirror and the focusing mirror to the image plane to improve disadvantages of traditional Czerny-Turner structure. Designed results demonstrate that aberrations are substantially corrected and high image quality can be obtained in broad waveband. The photon counting Wedge-Strip-Anode detector with micro-channel planes as the receiving plane is accepted for the instrument prototype. The other photon counting 2-D detector responding well for weak light such as Cross-Delay line detector and MAMA detector can also be used for detection. The calibration and performances testing system is made of a vacuum system a deuterium lamp a monochrometer and the instrument prototype. Results obtained from the experiment show that the spectral resolution is 2.4 nm and the spatial resolution is 80 m. The other calibration experiments are running. The technology of the spectrometer prototype is important for the research and applications of ionosphere remote sensing. 2011 SPIE.

Precision detection of CCD splicing based on template matching algorithm (EI CONFERENCE) 会议论文 OAI收割
IEEE 2nd International Conference on Computing, Control and Industrial Engineering, CCIE 2011, August 20, 2011 - August 21, 2011, Wuhan, China
作者: Zhang X.; Zhang X.; Yang L.; Zhang X.; Yang L.

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The remote sensing camera in large field and wide cover needs CCD with enough pixels. But the existing CCD cannot satisfy the practical needs. Therefore several pieces of CCD which has insufficient pixels are spliced to get a long CCD array with plenty of pixels. The precision requirements of CCD splicing are very strict so that the same high accuracies are required in the precision detection of CCD splicing. When detecting precision of CCD splicing the graphical markers with simple geometric structure in the CCD package are selected as templates. The position precision data of the graphical markers in each CCD are obtained using the template matching algorithm. Using the unified objective templates the focal plane which has multi-chip of CCD is detected by template matching algorithm. Experiment results show that the template matching algorithm can enhance the located precision of each CCD to 0.347m. The splicing precision detection with template matching algorithm can avoid the subjective error caused by the conventional detection method. And its results are more accurate. In addition without manual intervention in the process of precision detection the efficiency of precision detection is improved. 2011 IEEE.

The effect of different oriented sapphire substrates on the growth of polar and non-polar ZnMgO by MOCVD 期刊论文 OAI收割
journal of crystal growth, 2011, 卷号: 314, 期号: 1, 页码: 39-42
作者: Song HP; Shi K; Sang L; Wei HY

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Metal organic chemical vapor deposition Sapphire Zinc compounds Semiconducting II-VI materials VAPOR-PHASE EPITAXY OPTICAL-PROPERTIES ZNO NANORODS RAMAN-SCATTERING M-PLANE FILMS PHOTOLUMINESCENCE DEPOSITION NANOWIRES FIELDS

Dual-band quantum well infrared photodetectors with two ohmic contacts 期刊论文 OAI收割
acta physica sinica, 2011, 卷号: 60, 期号: 9, 页码: 98401
Huo YH; Ma WQ; Zhang YH; Huang JL; Wei Y; Cui K; Chen LH

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FOCAL-PLANE ARRAYS SIMULTANEOUSLY WORKING MU-M DETECTOR

Study on the azimuth bearing scheme of a large Alt-azimuth telescope (EI CONFERENCE) 会议论文 OAI收割
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Large Mirrors and Telescopes, April 26, 2010 - April 29, 2010, Dalian, China
作者: Wang H.; Dai S.; Zhang J.; Wang H.; Zhang J.

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The azimuth bearing schemes in typical large Alt-azimuth telescopes especially the 3.5-m APO telescope and the 4.1-m SOAR telescope were analyzed. A scheme of high-angular contacted thrust ball bearing integrated with a radial ball bearing was put forward. According to the Hertz contact theory the corresponding parameters were designed for engineering application. The static performance parameters within the range of 60 85 original contact angle were calculated. Compared with the traditional plane thrust ball bearing the results shows that the high-angular (80) contact thrust ball bearing has more benefits at bearing strength and rigidity for large telescope. The 1500mm diameter prototyping bearing shows good performance including the axial jitter is 0.009mm the radial jitter is 0.006mm the maximum starting torque without load is 30N·m and the load capacity is more than 30t which offers advanced technique path for the buildup of the high precision azimuth shafting and the whole telescope system. 2010 Copyright SPIE - The International Society for Optical Engineering.

Application of precision harmonic gear drive in focusing mechanism of space camera (EI CONFERENCE) 会议论文 OAI收割
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Smart Structures and Materials in Manufacturing and Testing, April 26, 2010 - April 29, 2010, Dalian, China
作者: Zhang X.; Zhang X.; Zhang X.

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A kind of precision harmonic gear drive in the focusing mechanism of space camera is studied which adopt external meshing complex wave transmission mode. Wave generator is combined with an elliptic cam and a flexible bearing around it. Flexspline is a structure of single wave with the same teeth. The output shaft is supported by a single cross-roller bearing. Ball screws connected the output shaft translate the rotational motion to the linear motion and drive the focusing mirror repeated moving along the linear guide. The output rigid wheel is connected with absolute encoder to detect displacement of focusing movement. It has the characteristics of big transmission ratio high precision compact structure high efficiency and smooth running etc. According to the practical application of this harmonic gear drive in the space camera the location relationship between the displacement of focusing structure and the focal plane movement is derived and the system error is analyzed its accuracy is tested with the open-loop control method. Experimental results show that transmission ratio of the instrument is 1:70 repeated positional accuracy is 2m which meet the requirements for use. 2010 SPIE.

Inspection focus technology of space tridimensional mapping camera based on astigmatic method (EI CONFERENCE) 会议论文 OAI收割
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optoelectronic Materials and Devices for Detector, Imager, Display, and Energy Conversion Technology, April 26, 2010 - April 29, 2010, Dalian, China
作者: Wang Z.; Wang Z.; Zhang L.; Zhang L.

收藏 | 浏览/下载：25/0 | 提交时间：2013/03/25

The CCD plane of the space tridimensional mapping camera will be deviated from the focal plane(including the CCD plane deviated due to camera focal length changed) under the condition of space environment and vibration impact when satellite is launching image resolution ratio will be descended because defocusing. For tridimensional mapping camera principal point position and focal length variation of the camera affect positioning accuracy of ground target conventional solution is under the condition of vacuum and focusing range calibrate the position of CCD plane with code of photoelectric encoder when the camera defocusing in orbit the magnitude and direction of defocusing amount are obtained by photoelectric encoder then the focusing mechanism driven by step motor to compensate defocusing amount of the CCD plane. For tridimensional mapping camera under the condition of space environment and vibration impact when satellite is launching if the camera focal length changes above focusing method has been meaningless. Thus the measuring and focusing method was put forward based on astigmation a quadrant detector was adopted to measure the astigmation caused by the deviation of the CCD plane refer to calibrated relation between the CCD plane poison and the asrigmation the deviation vector of the CCD plane can be obtained. This method includes all factors caused deviation of the CCD plane experimental results show that the focusing resolution of mapping camera focusing mechanism based on astigmatic method can reach 0.25 m. 2010 Copyright SPIE - The International Society for Optical Engineering.

The method on the measurement of the aircraft attitude by the spatial cosines relationship of the single station and planes to the intersection the multi-station of electro-optical theodolite (EI CONFERENCE) 会议论文 OAI收割
2010 International Conference on Computer, Mechatronics, Control and Electronic Engineering, CMCE 2010, August 24, 2010 - August 26, 2010, Changchun, China
Zhao L.-R.; Cao Y.-G.

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In order to realize the aircraft attitude measurement The paper advances electro-optical theodolite methods of measuring the aircraft attitude by using the spatial cosines relationship the single station theodolite and how to use intersection of the multi-station theodolite. The single station theodolite was introduced in a measured distance from the aircraft posture information. An exhaustive approach was used to access to the aircraft axis of the feature points and the location in the space was used to obtain space posture parameters. The multi-station theodolite was introduced to get the information of the aircraft flight attitude by method of using planes to the intersection. Two-dimensional image to obtain objective axis by fitting algorithm using Hough transform. And then Calculate the vertical distance of the origin to the target of the central axis and the origin to the target of the central axis of the angle between the normal and the X-axis obtaining the linear equation in the two-dimensional plane. Two-dimensional axis of the target image and the camera system's optical center only identified a space plane. The aircraft yaw axis angle and pitch angle can be obtained by getting the space axis using plains to the intersection method. Experimental results show that attitude angle error of the single station theodolite is less than 1 when its distance is less than 6000m and attitude angle error of the multi-station theodolite is less than 0.6 when its intersection angle is between 30 and 150. In this paper according to test result of precision comparing the mathematical model is correct and the algorithm is reasonable in extracting effective parameters of the aircraft's attitude. 2010 IEEE.

Manufacture for ruling concave metal grating with a long focal length (EI CONFERENCE) 会议论文 OAI收割
2010 International Conference on Computer, Mechatronics, Control and Electronic Engineering, CMCE 2010, August 24, 2010 - August 26, 2010, Changchun, China
Gao J.-X.

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The ruling technique for concave metal grating with long curvature radius (namely long focal length) is studied. In order to rule the concave grating with a long focal length the diamond carriage with elastic thimble mode is designed and manufactured. It is available not only to rule plane grating but to concave grating with a long focal length. The mathematic expression between the curvature radius of circular arc cutting edge of ruling tools for grating and the curvature radius of concave grating the caliber of grating and the size of transverse direction of bit tool are given. The span of curvature radius of circular arc cutting edge is analyzed theoretically. The concave metal grating with 30m curvature radius for 10.6m laser system is manufactured. The testing result shows that the quality of groove is perfect and the diffraction efficiency is more than 95.6 percent. 2010 IEEE.