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	Imaging of buried obstacles in a two-layered medium with phaseless far-field data 期刊论文 OAI收割 INVERSE PROBLEMS, 2021, 卷号: 37, 期号: 5, 页码: 26 作者: Li, Long; Yang, Jiansheng; Zhang, Bo; Zhang, Haiwen \| 收藏 \| 浏览/下载：26/0 \| 提交时间：2021/06/01 two-layered medium buried obstacle phaseless far-field data direct imaging method recursive Newton-type iteration algorithm
	Recovering Unbounded Rough Surfaces with a Direct Imaging Method 期刊论文 OAI收割 ACTA MATHEMATICAE APPLICATAE SINICA-ENGLISH SERIES, 2020, 卷号: 36, 期号: 1, 页码: 119-133 作者: Zhang, Hai-wen \| 收藏 \| 浏览/下载：27/0 \| 提交时间：2020/05/24 direct imaging method inverse scattering problem unbounded rough surface incident plane wave near-field data
	A direct imaging method for half-space inverse elastic scattering problems 期刊论文 OAI收割 Inverse Problems, 2019, 卷号: 35, 期号: 7 作者: Chen,Zhiming; Zhou,Shiqi \| 收藏 \| 浏览/下载：38/0 \| 提交时间：2019/10/28 reverse-time migration elastic wave direct imaging method
	NEAR-FIELD IMAGING OF AN UNBOUNDED ELASTIC ROUGH SURFACE WITH A DIRECT IMAGING METHOD 期刊论文 OAI收割 SIAM JOURNAL ON APPLIED MATHEMATICS, 2019, 卷号: 79, 期号: 1, 页码: 153-176 作者: Liu, Xiaoli; Zhang, Bo; Zhang, Haiwen \| 收藏 \| 浏览/下载：37/0 \| 提交时间：2019/12/13 inverse elastic scattering unbounded rough surface Dirichlet boundary condition direct imaging method near-field Cauchy data
	Fast imaging of scattering obstacles from phaseless far-field measurements at a fixed frequency 期刊论文 OAI收割 INVERSE PROBLEMS, 2018, 卷号: 34, 期号: 10, 页码: 24 作者: Zhang, Bo; Zhang, Haiwen \| 收藏 \| 浏览/下载：35/0 \| 提交时间：2018/10/07 inverse scattering Helmholtz equation phaseless far-field data direct imaging method
	Direct information retrieval after 3D reconstruction in grating-based X-ray phase-contrast computed tomography 期刊论文 OAI收割 JOURNAL OF SYNCHROTRON RADIATION, 2018, 卷号: 25, 页码: 1222-1228 作者: Wu, Z; Gao, K; Wang, ZL; Wei, CX; Wali, F \| 收藏 \| 浏览/下载：28/0 \| 提交时间：2019/09/24 direct information retrieval method grating-based phase-contrast imaging differential phase-contrast imaging computed tomography
	Modulation transfer function measurement of sampled imaging systems in field test (EI CONFERENCE) 会议论文 OAI收割 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 作者: Yang L.; Zhang J.; Zhang J.; Zhang J.; Wang J. 收藏 \| 浏览/下载：27/0 \| 提交时间：2013/03/25 A digital mirror device (DMD) based light projector was developed as the target generator in modulation transfer function (MTF) measurement. In order to overcome the sampling-scene phase effect in MTF measurement of sampled imaging systems a method using random targets is introduced to yield a phase-averaged MTF. The main potential problem of implementing this method is the fact that the stationary assumption of the random targets may be vitiated in practical measurement especially in field test due to the ill condition. We provide an efficient model-independent way of analyzing and isolating the spectral contents arising from these additional contributions to MTF measurement. Algorithms with adaptive parameter selection were also developed for spectral estimation of the test image in order to overcome the challenge brought by the size limit of the test matrices for one certain field of view derived from the isoplantic region. The MTF measurement of a CCD video imager is used to demonstrate the measurement technique and illustrate the benefits over other methods. In order to validate the results comparisons have been made between MTF measurements of imager implemented using this method and bar target direct measurements. 2010 Copyright SPIE - The International Society for Optical Engineering.
	Narcissus analysis for cooled staring IR system (EI CONFERENCE) 会议论文 OAI收割 3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Advanced Optical Manufacturing Technologies, July 8, 2007 - July 12, 2007, Chengdu, China 作者: Zhang X.; Zhang X.; Zhang X. 收藏 \| 浏览/下载：26/0 \| 提交时间：2013/03/25 Narcissus can have a deleterious effect on image quality for cooled infrared imaging systems. Therefore analysis of narcissus is important for designing both scanning and staring optics. Narcissus is generally assumed to be negligible in staring IR optical designs because the shading effects can be removed by calibration of the detector array data. However the calibration usually decreases sensitiveness of the system and Narcissus variation may be noticeable for sensors when the conditions changes as follows: 1. warming and cooling the optical housing 2. zooming optical elements 3. movement of lenses for focus. In that case it will result in shading and other image defects even after calibration. To minimize these effects narcissus should be assessed and controlled during the design of staring array IR system. We provided a direct and fast method for analyzing the narcissus variation in the presence of software such as LightTools TracePro and ASAP and proposed the principles in optical design of staring IR systems to reduce narcissus. A cooled staring IR system with serious narcissus was estimated and reoptimized. Narcissus analysis of this IR system confirmed the efficiency of the analysis method.