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The role of edge-based and surface-based information in natural scene categorization: Evidence from behavior and event-related potentials 期刊论文  OAI收割
CONSCIOUSNESS AND COGNITION, 2016, 卷号: 43, 期号: 6, 页码: 152-166
作者:  Fu, Qiufang;  Liu, Yong-Jin;  Dienes, Zoltan;  Wu, Jianhui;  Chen, Wenfeng
收藏  |  浏览/下载：26/0  |  提交时间：2016/09/18
Roughness analysis of optical surfaces by X-ray scattering (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:  Chen B.;  Chen B.
收藏  |  浏览/下载：25/0  |  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.  
Theoretical analysis of emission characteristics of second-order distributed feedback semiconductor lasers (EI CONFERENCE) 会议论文  OAI收割
Semiconductor Lasers and Applications IV, October 18, 2010 - October 19, 2010, Beijing, China
作者:  Liu Y.;  Liu Y.;  Qin L.;  Liu Y.;  Wang L.
收藏  |  浏览/下载：24/0  |  提交时间：2013/03/25
Based on the modified coupled-wave theory  the emission characteristics  including threshold gain  photon density distribution in the cavity  and external differential quantum efficiency for second-order DFB lasers are investigated. Numerical simulation results show that for given device structure with wavelength of 1.55 m  the feedback coupling coefficient and the surface radiation coupling coefficient of the second-order grating have great influence on the emission characteristics of the device. By choosing different duty cycles of the grating  we can change the two coupling coefficients  which affect the emission characteristics. For an overall consideration  an optimal duty cycle of 0.43 is chosen. The optimized results show that the device works without degeneracy modes and spatial burning hole. Besides  the side-mode suppress ratio (SMSR) and external differential quantum efficiency reach as high as 42 dB and 47%  respectively. 2010 SPIE.  
Study on the influence and disposal method of the micro-cracks of optical components (EI CONFERENCE) 会议论文  OAI收割
4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies, November 19, 2008 - November 21, 2008, Chengdu, China
作者:  Xuan B.;  Xie J.-J.;  Xie J.-J.;  Zhang H.;  Zhang H.
收藏  |  浏览/下载：24/0  |  提交时间：2013/03/25
Micro-crack is one of the most effective factor to the intensity and service life of optical components. Owing to the micro-crack on surface  actual strength of optical components is reduced severely  even less than ten-percent of its theoretical strength. According to fracture mechanics  the mechanisms of the formation and propagation of micro-crack and the growth theory of sub-critical micro-crack are discussed in the paper firstly. Based on practice  an on-line test method disposing etching holes-the molecule-infiltrating method and the principles of acid-etching method disposing micro-crack are described. Followed by the demolishing mechanism of abrasives and a more reasonable removal redundancy of fine-grinding and polishing during  optical production is given by using abrasives in different-size orderly. 2009 SPIE.  
Design of aspherical surfaces for panoramic imagers using multipopulations genetic algorithm (EI CONFERENCE) 会议论文  OAI收割
4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies, November 19, 2008 - November 21, 2008, Chengdu, China
作者:  Jin C.-S.;  Wang L.-P.;  Liang Z.-Z.
收藏  |  浏览/下载：27/0  |  提交时间：2013/03/25
A design method of aspherical surface for panoramic imaging system with two mirrors using multi-populations genetic algorithms is proposed. Astigmatism induced by mirrors may significantly compromise image resolution. To solve this problem  we induced algebraic expression of astigmatism in panoramic imager based on generalized Coddington equation and theory of geometric optics. Then  we propose an optimization process for mirror profile design to eliminate astigmatism and provide purposely-designed projection formula with aid of MPGA. A series of polynomial expressions of aspherical surfaces are obtained and procedures of the design are presented. In order to facilitate ray tracing and aberration calculation  even asphere surface model is obtained by using of hybrid schemes combining MPGA and damped least squares. Finally  a prototype of the catadioptric panoramic imager has been developed and panoramic ring image is obtained. 2009 SPIE.  
Test of an off-axis asphere by subaperture stitching interferometry (EI CONFERENCE) 会议论文  OAI收割
4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, November 19, 2008 - November 21, 2008, Chengdu, China
作者:  Zheng L.-G.;  Zhang X.-J.;  Zhang Z.-Y.;  Zhang Z.-Y.;  Deng W.-J.
收藏  |  浏览/下载：52/0  |  提交时间：2013/03/25
A new method combined subaperture stitching with interferometry(SSI) is introduced. It can test large and off-axis aspheric surfaces without the aid of other null optics. In this paper the basic principle and theory of the technique are analyzed. The synthetical optimization stitching model and effective stitching algorithm are established based on homogeneous coordinates transformation and simultaneous least-squares method. The software of SSI is devised and the prototype for testing of large aspheres by SSI is designed and developed. An off-axis asphere with the aperture of 376mm188mm is tested by this method. For comparison and validation  and the difference of PV and RMS error between them is 0.047 e and 0.006 e  the asphere is also tested by null compensation.The synthesized surface profile is consistent to that ofthe entire surface from null test  respectively. So it provides another quantitative measurement for testing large aspheric surfaces and off-axis aspheres besides null-compensation. 2009 SPIE.  
Design and tolerance analysis of compensator for high order aspheric surface testing (EI CONFERENCE) 会议论文  OAI收割
2009 International Conference on Optical Instruments and Technology - Optoelectronic Measurement Technology and Systems, October 19, 2009 - October 22, 2009, Shanghai, China
作者:  Chen X.;  Liu W.;  Chen X.;  Chen X.
收藏  |  浏览/下载：28/0  |  提交时间：2013/03/25
High accuracy is required in surface testing of 90nm nodal point lithography projecting lens. By comparing various aspheric surface testing methods  the structure layout of the compensator is a meniscus positive lens combined with a Plano-convex positive lens. The design results indicate that: primary and high order aberrations are balanced well  we adopt Offner null compensator to test the aspheric surface in the point diffraction interferometer at last. In this paper  MTF exceeds diffraction limit  an Offner compensator is presented on the base of the third order aberration theory to test concave aspheric surface  root-mean-square (RMS) of wave front error /167. The F-number of the system can achieve F/1.64. By the analysis of the process of aspheric surface testing with the designed system  the optical construction parameters of which is determined by introducing equal-quantities spherical aberration to compensate all orders of aspheric coefficients. The field of view of the system is 0.02  a loosen distribution of the tolerance was presented based on the accuracy of measuring apparatus. 2009 SPIE.  
Assessment of surface roughness by use of soft x-ray scattering (EI CONFERENCE) 会议论文  OAI收割
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：27/0  |  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.  
A high-speed acquisition and processing system of the laser speckle signal on the magnetic fluid (EI CONFERENCE) 会议论文  OAI收割
International Symposium on Photoelectronic Detection and Imaging 2009: Laser Sensing and Imaging, June 17, 2009 - June 19, 2009, Beijing, China
作者:  Sun Y.
收藏  |  浏览/下载：27/0  |  提交时间：2013/03/25
In order to achieve the dynamical detection and real-time analysis of the movement status of the magnetic fluid  according to the difficulties of the detection of the magnetic fluid  established a high-speed acquisition and processing system of laser speckle signal on the magnetic fluid. First of all  the FPGA (EP2C8T144C8N) drived the linear array CCD(TCD1501D) to scan in the corresponding time sequence given by the computer  collected the laser speckle interferometric image in rapid change on the surface of the magnetic fluid  which followed the movement of the magnetic fluid  and the signal collected by CCD was converted into the digital data through the high-speed A/D convertor and stored into the internal buffer FIFO of the FPGA  whose width and depth were designed by the user as required. Then  the FPGA sent the digital signal of the laser speckle interferometric images into the computer through the USB2.0 highspeed differential bus  whose transmission rate can reach 480Mb/s in theory. Finally  the distribution of the laser speckle on the magnetic fluid was messy and random  which carried certain information about the surface of the magnetic fluid  based on the theories of the statistic correlation and the subdivision of images  analysing and processing the laser speckle interferometric images  indirectly got the movement status of the magnetic fluid under the electromagnetic field. The experimental results show that: the High Speed Acquisition and Processing System has the advantage of full-court  non-contact  non-invasive  high-precision and high reliability and so on. The detection resolution of high speed acquisition and processing system is superior to 1m and the sample rate is 3Msps  which basically meets the requirements of the magnetic fluid movement state detection. 2009 SPIE.  
Annular sub-aperture stitching interferometry for testing of large asphreical surfaces (EI CONFERENCE) 会议论文  OAI收割
International Symposium on Photoelectronic Detection and Imaging, ISPDI 2007: Optoelectronic System Design, Manufacturing, and Testings, September 9, 2007 - September 12, 2007, Beijing, China
作者:  Zheng L.-G.;  Zhang X.-J.;  Deng W.-J.;  Wang X.-K.
收藏  |  浏览/下载：76/0  |  提交时间：2013/03/25
Annular subaperture stitching interferometric technology can test large-aperture  and the PV and RMS of residual error of the full aperture phase distribution is 0.027 and 0.0023  high numerical aperture aspheric surfaces with high resolution  the relative error of PV and RMS is -0.53% and -0.31%  respectively. The results conclude that this splicing model and algorithm are accurate and feasible. So it provides another quantitive measurement for test aspheric surfaces especially for large aperture aspheres besides null-compensation.  low cost and high efficiency without auxiliary null optics. In this paper  the basic principle and theory of the stitching method are introduced  the reasonable mathematical model and effective splicing algorithm are established based on simultaneous least-squares method and Zernike polynomial fitting. The translation errors are eliminated from each subaperture through the synthetical optimization stitching mode  it keeps the error from transmitting and accumulating. The numerical simulations have been carried on by this method. As results  the surface map of the full aperture after stitching is consistent to the input surface map  the difference of PV error and RMS error between them is -0.0074 and -0.00052 ( is 632.8nm)  respectively