中国开放科研知识云: 检索

Fast tracking of moving target combining SURF and cluster analysis 会议论文
Asia Pacific Conference on Optics Manufacture 2012, APCOM 2012, August 26, 2012 - August 28, 2012, Changchun, China
Li Y.; Yu J. J.; Fu Y.; Xu Z.; Zhou X.

收藏 | 浏览/下载：7/0 | 提交时间：2014/05/15

The research on statistical properties of TDI-CCD imaging noise (EI CONFERENCE) 会议论文
International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Imaging Detectors and Applications, May 24, 2011 - May 26, 2011, Beijing, China
Gu Y.-Y.; Shen X.-H.; He G.-X.

收藏 | 浏览/下载：17/0 | 提交时间：2013/03/25

TDI-CCD can improve the sensitivity of space camera without any degradation of spatial resolution which is widely used in aerospace imaging devices. The article describes the basic working principle and application characteristics of TDI-CCD devices analyses the composition of TDI-CCD imaging noise and propose a new method to analyze TDI-CCD imaging noise with statistical probability distribution. In order to estimate the distribution of gray values affect by noise we introduced the concept of skewness and kurtosis. We design an experiment using constant illumination light source take image with TDI-CCD working at different stage such as stage 16 stage 32 stage 48 stage 64 and stage 96 analyse the characteristics of image noise with the method we proposed experimental results show that the gray values approximately meet normal distribution in large sample cases. 2011 SPIE.

Design of compound Fresnel-R lenses for new high-efficient photovoltaic concentrator (EI CONFERENCE) 会议论文
Nonimaging Optics: Efficient Design for Illumination and Solar Concentration VII, August 1, 2010 - August 4, 2010, San Diego, CA, United states
Jing L.; Liu H.; Lu Z.; Zhao H.

收藏 | 浏览/下载：24/0 | 提交时间：2013/03/25

A new design of compound Fresnel-R concentrator is presented which is composed of two lenses: a primary lens (Fresnel lens) that works by total internal reflection at outer facets but refraction at inner facets and a secondary lens that works by refraction. In contrast to previous Fresnel lens concentrator this design increases the acceptance angle improves the irradiance uniformity on the solar cell and reduces the aspect ratio significantly. Another outstanding advantage of this concentrator is the fact that it mainly works by performing total internal reflection reducing chromatic dependence as well as Fresnel losses. An optical efficiency more than 80% can be achieved. Moreover in order to reduce the influence of manufacture accuracy and to increase the optical efficiency further the central part of the bottom of the secondary lens which directly adhered to the solar cell is designed as a cone-shaped prism to collect the sunlight that doesn't reach the solar cell. 2010 SPIE.

A design on a control method of a new type of focal plane shutter (EI CONFERENCE) 会议论文
2010 International Conference on Computer, Mechatronics, Control and Electronic Engineering, CMCE 2010, August 24, 2010 - August 26, 2010, Changchun, China
Xue L.; Ming L.; Zheng L.-N.; Zhou J.-F.; Zhang H.-W.; Zhang J.-C.

收藏 | 浏览/下载：24/0 | 提交时间：2013/03/25

In order to ensure appropriate exposure time and no exposure while electric charge is transferring after taking a photograph it is necessary to have the shutter mechanism cooperate with CCD for area CCD aerial cameras. The ground object illumination has a wide range which is from 4000Lx to 100000Lx so a shutter which is high efficient and a continuous stepless adjustment are also required. This paper introduces the fundamental principle structural design and control procedure about this new focal plane shutter. Under the control of DSP the velocity of shutter curtain governed by the shutter motor can be not only precisely controlled but also the durability and the reliability are increased. The experiment results have shown that this new shutter has the higher stability of movement long life span with more than 105 operating times a wide range of exposure time from1/ 50s to 1/ 320s(depending on the slit width)and the exposure error is less than 10%. With the CCD gain adjustment the performance of this shutter is fully satisfied with the requirements of area CCD aerial cameras. 2010 IEEE.

A Design of Beam Shaping Unit for 193nm Lithography Illumination System Using Angular Spectrum Theory 会议论文
2010
Zhao Y.; Gong Y.; Li S.; Zhang W.

收藏 | 浏览/下载：24/0 | 提交时间：2013/03/28

A design of beam shaping unit for 193nm lithography illumination system using angular spectrum theory (EI CONFERENCE) 会议论文
6th International Symposium on Precision Engineering Measurements and Instrumentation, August 8, 2010 - August 11, 2010, Hangzhou, China
Zhao Y.; Gong Y.; Li S.; Zhang W.

收藏 | 浏览/下载：16/0 | 提交时间：2013/03/25

Off-axis illumination (OAI) technology is widely used to enhance resolution for deep ultraviolet lithography. The realizing methods of OAI include geometrical optics method and physical optics method. However the former has the disadvantage of weak intensity distribution controlling ability and the latter introduces simulation errors evidently when dealing with near field diffraction propagation. A diffractive optical element (DOE) designing method using plane wave angular spectrum theory is presented in this paper. Several kinds of OAI modes at near field away from DOE can be realized and simulation errors and the size of illuminator are also reduced. According to studying the relationships of the sampling point distance of DOE light beam propagation distance and the structure of the beam shaping unit a method of determining the designing parameters is discussed. Using this method several illumination modes are realized and simulation results show that all diffraction efficiencies reach up to 84%. The method of DOE manufacturing is analyzed at last and it is proven to be feasible. 2010 SPIE.

Key techniques of laser direct writing patterns on spherical substrate (EI CONFERENCE) 会议论文
3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Design, Manufacturing, and Testing of Micro- and Nano-Optical Devices and Systems, July 8, 2007 - July 12, 2007, Chengdu, China
Feng X.-G.; Zhao J.-L.

收藏 | 浏览/下载：17/0 | 提交时间：2013/03/25

Comparing with the writing method of plane pattern spherical pattern' has some remarkable different on several points. Firstly it is difficult to spin-coated a uniform photoresist film on a spherical substrate especially the ratio of spherical radius to caliber is smaller and the spin-coated way must match the ratio of spherical radius to caliber. Secondly if the sphere couldn't be regarded as a plane a so-called concentric optical scan movement way must be applied for the generation of spherical pattern because the reflex of substrate will affect the quantity of illumination. Commonly an alignment technique is indispensable with pattern generation of spherical surface by the concentric optical scan in order to ensure the orthogonal intersection of focusing laser beam and writing surface. Thirdly a uniform velocity control must be considered for the laser direct writing method on a spherical substrate. Otherwise the exposure time of photoresist will be different and the line widths of pattern will be also different at different areas. Fourthly commonly because the errors of concentric machine and substrate surface shape are bigger so focusing servo-control technique is also needful for writing a pattern on a spherical substrate. Focusing servo-control may keep the focal spot on the spherical surface by a focus detection and control system in the course of writing pattern. Using these techniques we fabricated a line width of 7m and a period of 600m isometric mesh on the concave of a spherical substrate.

Target track system design based on circular projection (EI CONFERENCE) 会议论文
ICO20: Optical Information Processing, August 21, 2005 - August 26, 2005, Changchun, China
Song H.-J.; Zhu M.; Hu S.; Shen M.-L.

收藏 | 浏览/下载：15/0 | 提交时间：2013/03/25

Template matching is the process of searching the present and the location of a reference image or an object in a scene image. Template matching is a classical problem in a scene analysis: given a reference image of an object decide whether that object exists in a scene image under analysis and find its location if it does. The template matching process involves cross-correlating the template with the scene image and computing a measure of similarity between them to determine the displacement. The conventional matching method used the spatial cross-correlation process which is computationally expensive. Some algorithms are proposed for this speed problem such as pyramid algorithm but it still can't reach the real-time for bigger model image. Moreover the cross-correlation algorithm can't be effective when the object in the image is rotated. Therefore the conventional algorithms can't be used for practical purpose. In this paper an algorithm for a rotation invariant template matching method based on different value circular projection target tracking algorithm is proposed. This algorithm projects the model image as circular and gets the radius and the sum of the same radius pixel value. The sum of the same radius pixel value is invariable for the same image and the any rotated angle image. Therefore this algorithm has the rotation invariant property. In order to improve the matching speed and get the illumination invariance the different value method is combined with circular projection algorithm. This method computes the different value between model image radius pixel sum and the scene image radius pixel sum so that it gets the matching result. The pyramid algorithm also is been applied in order to improve the matching speed. The high speed hardware system also is been design in order to meet the real time requirement of target tracking system. The results show that this system has the good rotate invariance and real-time property.

Study on color model conversion for camera with neural network based on the combination between second general revolving combination design and genetic algorithm (EI CONFERENCE) 会议论文
ICO20: Illumination, Radiation, and Color Technologies, August 21, 2005 - August 26, 2005, Changchun, China
Zhao H.; Li Z.; Wang C.; Sun J.; Zhou F.

收藏 | 浏览/下载：26/0 | 提交时间：2013/03/25

Munsell color system is selected to establish the mutual conversion between RGB and L*a*b* color model for camera. The color luminance meter and CCD camera synchronously measure the same color card XYZ value is gotten from the color luminance meter the training error is 0.000748566 it can show that the method combining second general revolving combination design with genetic algorithm can optimize the hidden-layer structure of neural network. Using the data of testing set to test this network and calculating the color difference between forecast value and true value the color picture captured from CCD camera is expressed for RGB value as the input of neural network and the L*a*b* value converted from XYZ value is regarded as the real color value of target card which the difference is not obvious comparing with forecast result the maximum is 5.6357 NBS namely the output of neural network. The neural network of two hidden-layers is considered the minimum is 0.5311 NBS so the second general revolving combination design is introduced into optimizing the structure of neural network and the average of color difference is 3.1744 NBS. which can carry optimization through unifying project design data processing and the precision of regression equation. Their mathematics model of encoding space is gained and the significance inspection shows the confidence degree of regression equation is 99%. The mathematics model is optimized by genetic algorithm optimization solution is gotten and function value of the goal is 0.0007168. The neural network of the optimization solution is trained

Illumination system design applied to LC rear projective TV system 会议论文
2002
Zhang Z. B.; Weng Z. C.; Chang J.; Cong X. J.

收藏 | 浏览/下载：10/0 | 提交时间：2013/03/28

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