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	A novel crystal-analyzer phase retrieval algorithm and its noise property 期刊论文 OAI收割 JOURNAL OF SYNCHROTRON RADIATION, 2015, 卷号: 22, 页码: 786-795 作者: Bao Y(鲍园); Wang Y(王研); Li PY(李盼云); Ju ZQ(鞠在强); Zhang K(张凯) 收藏 \| 浏览/下载：24/0 \| 提交时间：2016/04/18 diffraction enhanced imaging phase retrieval noise in imaging systems
	Design and image restoration research of a cubic-phase-plate system (EI CONFERENCE) 会议论文 OAI收割 5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies, April 26, 2010 - April 29, 2010, Dalian, China 作者: Zhang J.; Zhang J.; Zhang J.; Shi G.; Zhang X. 收藏 \| 浏览/下载：25/0 \| 提交时间：2013/03/25 Wave-front coding technology is a novel jointly optical and digital imaging technology which can greatly extend the depth of focus of optical systems. The image restoration process is an important part of wave-front coding technology. Using wave-front coding makes the modulation transfer function(MTF) values of the optical systems change little over a range of several times the depth of focus which means the system MTF is quite insensitive to defocus and there is no zero in the passband. So we can design a single filter for the restoration of images in different defocus positions. However it's hard to avoid noise during image acquisition and transmission processes. These noises will be amplified in the image restoration especially in the high frequency part when the MTF drop is relatively low. The restoration process significantly reduces the system signal to noise ratio this way. Aimed at the problem of noise amplification a new algorithm was proposed which incorporated wavelet denoising into the iterative steps of Lucy-Richardson algorithm. Better restoration results were obtained through the new algorithm effectively solving the noise amplification problem of original LR algorithm. Two sets of identical triplet imaging systems were designed in one of which the cubic-phase-plate was added. Imaging experiments of the manufactured systems were carried and the images of a traditional system and a wave-front coded system before and after decoding were compared. The results show that the designed wave-front coded system can extend the depth of focus by 40 times compared with the traditional system while maintaining the light flux and the image plane resolution. 2010 Copyright SPIE - The International Society for Optical Engineering.
	The research for EO imaging system simulation (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: Wang L.-J.; Zhang X.; Zhang X.; Zhang X.; Zhang J.-P. 收藏 \| 浏览/下载：22/0 \| 提交时间：2013/03/25 Electric-Optical (EO) imaging systems are modern systems especially the one consists of aspheric optics and image processing called wavefront coding system. The design concept of this kind system is totally different from the traditional image system. The trade-off between the complexity of the image deconvolution and the depth of focus extended should be considered. So we establish a simulation model consisting of optical optimization design system signal-to-noise ratio analysis and recovered image evaluation. The data can be exchanged among them. This simulation tools will be very useful in system design process.