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	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：35/0 \| 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.
	New phase measurement method for laser rangefinder (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: Meng Z.; Meng Z. 收藏 \| 浏览/下载：34/0 \| 提交时间：2013/03/25 A new phase measurement method is designed and presented by using the technique of signal shifting phase and the technique of signal multiplication for laser rangefinder. The intensity of laser light is modulated by cosine circuit signal at the same time the cosine circuit signal is thansformed sine signal by the shifting phase technique. Two signals mentioned above are multiplied by received signal from the target respectively then being transmitted into signal processor after passing through low band filter respectively. The result of phase-shift between the received signal and sent signal is calculated by means of signal processor and time-counter with double frequency of modulation signal. The proposed system is composed of four units such as control and count unit emitting and receiving unit of laser light signal processing unit and result display unit. The two most advantages of proposed system over others are its ability of proper isolation which reduces crosstalk and its independency thermal drift. Theoretical calculations and experimental results have shown the accuracy better than 2 mm. 2010 Copyright SPIE - The International Society for Optical Engineering.
	基于U形塑料光纤的氧气传感器期刊论文 OAI收割中国激光, 2008, 卷号: 35, 期号: 8, 页码: 1220, 1223 初凤红; 蔡海文; 瞿荣辉; 方祖捷收藏 \| 浏览/下载：917/163 \| 提交时间：2009/09/18 光学器件 Fluorescence lifetime 氧气传感 Optical devices 塑料光纤 Oxygen sensor 荧光寿命 Phase modulation technique 相移法 Plastic optical fiber
	基于光纤环形镜的全光脉冲整形器期刊论文 OAI收割中国激光, 2005, 卷号: 32, 期号: 9, 页码: 1239, 1242 蒋运涛; 罗航; 袁鹏; 李学春; 钱列加收藏 \| 浏览/下载：1609/269 \| 提交时间：2009/09/18 激光技术 laser technique 脉冲整形 pulse shaping 光纤环形镜 nonlinear optical loop mirror 交叉相位调制 cross phase modulation
	室温下稳定的多波长掺铒光纤激光器的研究期刊论文 OAI收割光学学报, 2005, 卷号: 25, 期号: 6, 页码: 821, 824 孙国勇; 瞿荣辉; 杨敬; 王向朝; 方祖捷收藏 \| 浏览/下载：1589/150 \| 提交时间：2009/09/18 激光技术 laser technique 光纤激光器 fiber laser 相位调制 phase modulation 多波长 multi-wavelength