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浏览/检索结果: 共9条，第1-9条 帮助 限定条件 内容类型：会议论文    专题：长春光学精密机械与物理研究所    第一署名单位    第一作者单位    通讯作者单位     已选(0)清除 条数/页：5101520253035404550556065707580859095100   排序方式：请选择作者升序作者降序题名升序题名降序发表日期升序发表日期降序提交时间升序提交时间降序 Roughness analysis of optical surfaces by X-ray scattering (EI CONFERENCE) 会议论文 2011 International Conference on Electronics and Optoelectronics, ICEOE 2011, July 29, 2011 - July 31, 2011, Dalian, China Meng Y.; Chen B.; Chen C. 收藏  |  浏览/下载：18/0  |  提交时间：2013/03/25 A grazing incidence x-ray scattering (XRS) method  Order perturbation theory (FOPT)  is stated briefly and an experimental facility based on an improved X-ray diffraction has been introduced  which can work with high performance. The x-ray scattering distributions of two super smooth silicon samples measured at the incidence angle 0.2 degree  as the x-ray wavelength is 0.154 nm  have been given and analyzed by the FOPT to give information about the surface profiles. As a comparison  the root mean square (RMS) surface roughness  grey-scale maps and one-dimensional power spectral density (1D PSD) have been derived from the atomic-force microscope (AFM) data. The results evaluated by FOPT are in good agreement with that of AFM  which indicates that x-ray scattering method is a practical characterization for the investigation of super smooth surfaces. 2011 IEEE.   Research on automatic Hartmann test of membrane mirror (EI CONFERENCE) 会议论文 5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, April 26, 2010 - April 29, 2010, Dalian, China Zhong X.; Jin G.; Liu C.; Zhang P. 收藏  |  浏览/下载：21/0  |  提交时间：2013/03/25 Electrostatic membrane mirror is ultra-lightweight and easy to acquire a large diameter comparing with traditional optical elements  so its development and usage is the trend of future large mirrors. In order to research the control method of the static stretching membrane mirror  the surface configuration must be tested. However  membrane mirror's shape is always changed by variable voltages on the electrodes  and the optical properties of membrane materials using in our experiment are poor  so it is difficult to test membrane mirror by interferometer and null compensator method. To solve this problem  an automatic optical test procedure for membrane mirror is designed based on Hartmann screen method. The optical path includes point light source  CCD camera  splitter and diffuse transmittance screen. The spots' positions on the diffuse transmittance screen are pictured by CCD camera connected with computer  and image segmentation and centroid solving is auto processed. The CCD camera's lens distortion is measured  and fixing coefficients are given to eliminate the spots' positions recording error caused by lens distortion. To process the low sampling Hartmann test results  Zernike polynomial fitting method is applied to smooth the wave front. So low frequency error of the membrane mirror can be measured then. Errors affecting the test accuracy are also analyzed in this paper. The method proposed in this paper provides a reference for surface shape detection in membrane mirror research. 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 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 Zhang X.; Yan C. 收藏  |  浏览/下载：20/0  |  提交时间：2013/03/25 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.   Cr image enhancement based on human visual characteristics (EI CONFERENCE) 会议论文 2010 International Conference on Computer Design and Applications, ICCDA 2010, June 25, 2010 - June 27, 2010, Qinhuangdao, Hebei, China Zhang M.-H.; Zhang Y.-Y. 收藏  |  浏览/下载：19/0  |  提交时间：2013/03/25 The characteristic of digital CR medicine radiation image has wide dynamic range  abundant details and bad contrast  so it is necessary to enhance CR image to the need of doctor diagnosis. But the general enhancement algorithms don't consider human visual characteristics  so it puts forward CR medicine image adaptive enhancement algorithm combining the human visual property  which is more sensitive to smooth area noise compared with detail area noise  and makes image edge detail enhancement great in detail area  and detail enhancement little in smooth area  in which factor K is based on space change of image domain  accordingly gaining non-linear enhancement edge details of CR image. Experiment results demonstrate that the algorithm enhances CR image detail and CR image enhanced has good visual effect  so the method is fit for edge detail enhancement of CR medicine radiation image. 2010 IEEE.   White-light spectral scanning interferometry for surface measurement system (EI CONFERENCE) 会议论文 6th International Symposium on Precision Engineering Measurements and Instrumentation, August 8, 2010 - August 11, 2010, Hangzhou, China Wang C.; Cao N.; Lu J.; Guan J. 收藏  |  浏览/下载：20/0  |  提交时间：2013/03/25 The paper introduces the white-light spectral scanning interferometry for surface measurement. This interferometry can be used to measure the roughness of both smooth surfaces and those with large step heights. This real-time surface measurement can be achieved using acousto-optic tuneable filtering (AOTF) technique without mechanical scanning. At first  the structure and principle of this interferometry is introduced. Then the algorithm of the surface roughness measurement is proposed. What's more  the experiment with standard test piece is conducted. Compared with the traditional laser-light interferometry  the data shows that the proposed method has a higher accuracy which is proved to be nano-scale. A conclusion is given at last in which the superiorities and the limitations of the proposed system were discussed. 2010 SPIE.   Nonlinear control design for system with mechanical resonance based on two tracking-differentiators (EI CONFERENCE) 会议论文 2010 IEEE International Conference on Mechatronics and Automation, ICMA 2010, August 4, 2010 - August 7, 2010, Xi'an, China Huang P.; Ge W.; Li J.; Xiu J.; Li Y.; Chen L. 收藏  |  浏览/下载：15/0  |  提交时间：2013/03/25 A nonlinear control strategy for controlling a motion system with mechanical resonance is presented in this paper. A mathematical model of the servo system is derived according to the parameters of an actual system. By using two Tracking-Differentiators  reference input and system output are tracked and their differential signals are given simultaneously. A nonlinear PD control law in velocity loop is designed based on non-smooth feedback. The simulation results show that the control law is superior remarkably in performance to linear PD control law and the classical PID control law. Tracking-Differentiator resolves the contradiction between rapidity and overshoot of system response. The nonlinear PD control law improves system dynamic performance and intensifies the ability of disturbance rejection. The control design achieved in this paper makes the servo system more robust. 2010 IEEE.   Study on experiment of grinding SiC mirror with fixed abrasive (EI CONFERENCE) 会议论文 4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies, November 19, 2008 - November 21, 2008, Chengdu, China Wang X.; Zhang X.-J. 收藏  |  浏览/下载：16/0  |  提交时间：2013/03/25 A brand-new technology for manufacturing SiC reflecting mirror that is different from the traditional method is adopted  which is called as fixed abrasive surfacing technology. Not only the new method achieves better mirror quality with bigger diamond in diameter quickly  but also because of the fixed motion between the abrasive and workpiece and it will be good for surface finishing. During experiment  material removal characteristic which is on SiC under certain rotation speed and pressure by W7  W5  W3.5  W1.5 pellets has been tested. Through those removal curves  we come to a conclusion that the technology not only has a higher removal rate  but also has much more stability. In addition  the surface roughness experiment is mentioned. In the first stage  we achieved a mirror with surface roughness 42.758nm rms with W7 pellets. The surface roughness is descending as we change pellets with smaller diamond in diameter . At the end of experiment  a smooth surface with roughness 1.591nm rms has been achieved after using W1.5 pellets. Experiment results indicate that the technology which manufactures SiC reflecting mirror with fixed abrasive is able to replace the traditional slurry abrasive completely in certain finishing phase and also has a great foreground in application. 2009 SPIE.   Assessment of surface roughness by use of soft x-ray scattering (EI CONFERENCE) 会议论文 Soft X-Ray Lasers and Applications VIII, August 4, 2009 - August 6, 2009, San Diego, CA, United states Yan-li M.; Yong-gang W.; Shu-yan C.; Bo C. 收藏  |  浏览/下载：17/0  |  提交时间：2013/03/25 A soft x-ray reflectometer with laser produced plasma source has been designed  which can work from wavelength 8nm to 30 nm and has high performance. Using the soft x-ray reflectometer above  the scattering light distribution of silicon and zerodur mirrors which have super-smooth surfaces could be measured at different incidence angle and different wavelength. The measurement when the incidence angle is 2 degree and the wavelength is 1 lnm has been given in this paper. A surface scattering theory of soft x-ray grazing incidence optics based on linear system theory and an inverse scattering mathematical model is introduced. The vector scattering theory of soft x-ray scattering also is stated in detail. The scattering data are analyzed by both the methods above respectively to give information about the surface profiles. On the other hand  both the two samples are measured by WYKO surface profiler  and the surface roughness of the silicon and zerodur mirror is 1.3 nm and 1.5nm respectively. The calculated results are in quantitative agreement with those measured by WYKO surface profiler  which indicates that soft x-ray scattering is a very useful tool for the evaluation of highly polished surfaces. But there still some difference among the results of different theory and WYKO  and the possible reasons of such difference have been discussed in detail. 2009 SPIE.   Developing of in-suit long trance profiler for testing slope error of aspherical optical Elements (EI CONFERENCE) 会议论文 ICO20: Optical Devices and Instruments, August 21, 2005 - August 26, 2005, Changchun, China Zhou C.; Li H.; Chen C.; Zhou C.; Qian S. 收藏  |  浏览/下载：25/0  |  提交时间：2013/03/25 Profile error of super smooth surface of optical elements at X-ray/EUV in synchrotron radiation (SR) light beam line is described as slope error of them generally. The Long Trace Profiler (LPT) is used for testing surface slope error of SR optical elements in world generally. It is requisite to use In-suit LTP measuring surface thermal distortion of SR optical elements with high heat under high bright SR source. Authors design an In-suit LTP by means of co-path interferometer with pencil light beam. The instrument not only can be used for testing slope error of mirrors in Lab. also in situation test the distortion of mirror with high heat load at synchrotron light beam line. The device can be used to test various absolute surface figures of optical elements such as aspherieal  spherical and plane. It is needless standard reference surface. It is named by LTP-III. This paper describes its basic operating principle  optical system  mechanical constructions  DC serve motor control system  array detector  data acquisition system and computer system for controlling and data analysis of LTP-III. The Instrument has advantages of high accuracy  low cost  multifunction and wide application. Length of surface measured of optical element accuracy is 0.04 arcsec.