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	An artificial compound eye of photon Sieves 期刊论文 OAI收割 OPTICS AND LASER TECHNOLOGY, 2015, 卷号: 74, 页码: 93-96 作者: Jiang, Wenbo; Hu, Song; He, Yu; Bu, Yun 收藏 \| 浏览/下载：16/0 \| 提交时间：2015/09/21 Artificial compound eye Photon sieves Ommatidium Focusing performance Utilization ratio of energy Angle field of view
	Design and fabrication of cascaded X-ray planar parabolic compound refractive lens 期刊论文 OAI收割 ACTA PHYSICA SINICA, 2014, 卷号: 63, 期号: 19 Fu, ML; Le, ZC; Zhou, HQ; Zhang, M; Quan, BS; Wang, H; Mao, CW; Wang, CH; Shen, XY 收藏 \| 浏览/下载：56/0 \| 提交时间：2015/03/13 SYNCHROTRON-RADIATION FOCUSING PERFORMANCE
	Improved TOPS about direction of arrival estimation for wideband signals (EI CONFERENCE) 会议论文 OAI收割 2011 International Conference on Vibration, Structural Engineering and Measurement, ICVSEM2011, October 21, 2011 - October 23, 2011, Shanghai, China 作者: He B. 收藏 \| 浏览/下载：16/0 \| 提交时间：2013/03/25 The study about the direction-of-arrival (DOA) estimation for wideband signals is a basic topic of Signal Processing. The method called test of orthogonality of projected subspaces (TOPS) does not require initial values to form focusing matrix compared with the coherent signal subspace method (CSSM) but it has poor performance for coherent wideband signals at low signal-to-noise ratio (SNR). Based on the lack of the conventional TOPS this paper reconstructs a set of new matrices with the narrowband correlated matrices coming from the DFT decomposition of the array output and modifies the method frame of the conventional TOPS. So we get a set of reconstructed matrices with full rank corresponding to each frequency bin and which have no array aperture loss. The improved TOPS can estimate the DOA for coherent wideband sources at low SNR and enhances the performance of the conventional TOPS. Simulation results show that the improved TOPS is effective and the total performance of which is similar to the rotational signal-subspace (RSS) method. (2012) Trans Tech Publications.
	Design and experimental research of a new type focus mechanism used in space-based telescope (EI CONFERENCE) 会议论文 OAI收割 2012 9th IEEE International Conference on Mechatronics and Automation, ICMA 2012, August 5, 2012 - August 8, 2012, Chengdu, China 作者: Wang D. 收藏 \| 浏览/下载：34/0 \| 提交时间：2013/03/25 The position of focal plane will be changed because of temperature fluctuation and vacuum environment. In order to make the telescope work well positioning accuracy of the mechanism is 0.008mm. The performance satisfies the need of precision a focusing mechanism is needed. To majority of large space-based telescopes and the scheme design is reasonable and practicable. 2012 IEEE. the general way to do this would be to use a reflector which was located in the backfocal distance. One of typical schemes of this mechanism was introduced however because of the big axial size the mechanism can't be used when the size of the enclosure was limited. A new type of focusing mechanism was introduced which has such advantages of small size high accuracy and low mass. The design and test methods had been discussed. According to the results the repeatability positioning accuracy is 0.0025mm
	Model identification and closed-loop confirmation for opto-electronic platform of seeker (EI CONFERENCE) 会议论文 OAI收割 2010 2nd International Conference on Industrial Mechatronics and Automation, ICIMA 2010, May 30, 2010 - May 31, 2010, Wuhan, China 作者: Liu H.; Zhang J.; Zhang J.; Zhang J.; Chen J. 收藏 \| 浏览/下载：31/0 \| 提交时间：2013/03/25 A mathematical model of seeker opto-electronic platform is the basis for researching performance designing a servo control system and simulating. Focusing on high frequencies of mechanical resonant restriction of gimbaled axis rotation a new model identification method was proposed under the pseudo-random invert-M-sequences. The testing signal data acquisition the calculating of frequency response and least square identification were investigated. The realized steps are explicitly illustrated and the testing example is given in this paper the results confirm that the proposed method is effective and practical. 2010 IEEE.
	Fabrication and testing of hard X-ray hourglass lenses (EI CONFERENCE) 会议论文 OAI收割 Micro and Nano Technology - 1st International Conference Society of Micro/Nano Technology, CSMNT, November 19, 2008 - November 22, 2008, Beijing, China 作者: Zhu Y.; Wang W.; Wang W. 收藏 \| 浏览/下载：25/0 \| 提交时间：2013/03/25 Based on the refraction theory of the lens the SU-8 photoresist hard X-ray hourglass lenses with three different structure parameters are fabricated. The mask-back exposure technique is introduced to fabricate the lenses. The focusing performance of this device is tested at Beijing Synchrotron Radiation Facility (BSRF). At the distance of 1.65m from the lenses an obviously focusing performance in one dimension is observed. The relative intensity of the lenses with the largest gain is about 217.7 the gain of the lens is about 1.15 and the dimension of the focus is about 33m. The focusing performance of this device can be improved through the developing of the mask-back exposure technique. 2009 Trans Tech Publications Switzerland.
	Focusing high-energy x-rays by a PMMA compound x-ray lens on Beijing synchrotron radiation facility 期刊论文 OAI收割 CHINESE PHYSICS, 2007, 卷号: 16, 期号: 4, 页码: 984-988 作者: Le, ZC 收藏 \| 浏览/下载：26/0 \| 提交时间：2016/06/29 PMMA compound x-ray lens focusing performance Beijing synchrotron radiation facility (BSRF)
	Design of video auto focusing based on image processing (EI CONFERENCE) 会议论文 OAI收割 ICO20: Optical Information Processing, August 21, 2005 - August 26, 2005, Changchun, China Meng B.; Zhu M.; Cai C.-J. 收藏 \| 浏览/下载：19/0 \| 提交时间：2013/03/25 In order to realize the auto focusing technique based on digital image processing a video image processing system is designed by using high-performance digital signal processor TMS320VC5509 as the core field programmable gate array FPGA for preprocessing of image. At the same time it is proposed to use vector norm sum of image gray gradient as evaluation functions of digital image. It has the characteristics of good unbiasedness powerful unimodality etc. and can be applied to evaluation of defocusing. The hardware composition of the theory behind the auto focusing system and the application of the evaluation function are discussed in details.
	The three-dimensional focusing behaviors of the compound x-ray lenses (EI CONFERENCE) 会议论文 OAI收割 Optical Design and Testing II, November 8, 2004 - November 11, 2004, Beijing, United states Le Z.; Liu K.; Liang J.; Zhang M.; Quan B. 收藏 \| 浏览/下载：16/0 \| 提交时间：2013/03/25 A theoretical method for evaluating the three-dimensional focusing performances of the compound x-rays lenses is presented in the present paper. The relationship between the transverse and axial focusing behaviors is considered and a simple calculation that predicts the transverse and axial focusing behaviors of the compound x-ray lenses is also presented. As an example the three-dimensional focusing performance of a compound x-ray lens with Al material is predicted. The dependences of the three-dimensional focusing performances on the compound lenses' structural parameters are observed for the Al compound x-ray lens. Moreover the approximate tolerances in the setting of the receiving planes are also considered for x-rays of 4.95keV 14.99keV and 29.78keV.