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	The investigation of point defect modes of phononic crystal for high Q resonance (EI CONFERENCE) 会议论文 OAI收割 2011 16th International Solid-State Sensors, Actuators and Microsystems Conference, TRANSDUCERS'11, June 5, 2011 - June 9, 2011, Beijing, China 作者: Liu J.; Liu J.; Liu J.; Li F. 收藏 \| 浏览/下载：21/0 \| 提交时间：2013/03/25 Point defect cavity was constructed in a two-dimensional phononic crystal plate. It was excited by a small piezo chip in the cavity and the vibration of each point defect modes were detected by an optical interferometer. Point defect modes on 2D PC plate in vacuum air and loaded with water were investigated theoretically and experimentally to make clear of Q factors which are affected by inner attenuation band gap effects and medium. The way to get high Q resonance has been found. It helps to design a new kind of resonator or sensor. 2011 IEEE.
	Evaluation of the operating range for ground-based infrared imaging tracking system (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Infrared Imaging and Applications, May 24, 2011 - May 24, 2011, Beijing, China 作者: Zhang Z.-D. 收藏 \| 浏览/下载：49/0 \| 提交时间：2013/03/25 Ground-based infrared imaging tracking system (GIITS) is of great importance for aerial target warning and guard. The operating range is one of the key performance specifications on the other which should be calculated calculate the radiation power received on the detector in order to analysis whether the output signal meets the detection requirements or not analyzed and studied during the whole GIITS design process. The operating range is mostly influenced by a few factors without considering the effect of the background radiation. By improving of the traditional method including atmospheric attenuation a new operating range calculation model of the GIITS was established based on two requirements. One is that the image size of observed target should meet the requirement of the processor signal extraction. The number of the pixel occupied by target image should be more than 9. The other is that the signal noise ratio (SNR) of the GIITS should not be less than 5 to meet the requirements of the target detection probability and spatial frequency. The SNR calculation equation in form of energy is deduced and the radiation characteristic of the observed target and background are analyzed. When evaluate the operating range of the GIITS using the new method the performance of GIITS and feature of target and background. This paper firstly makes analysis and summarization on the definite localizations of the traditional operating range equation of the GIITS. The localizations are mainly in two aspects. On one hand we should successively calculate two operating range values according to two requirements mentioned above and choose the minimum value as the analytic result. In the end the dispersion of the image and the effect of image dispersion are not considered in the traditional method an evaluation of operating range for fighter aircraft is accomplished as an example. The influence factors in every aspect on operating range were explored by the calculated result. The new operating range calculation model provides the theoretical basis for the design and applications as well as the comprehensive evaluation of a GIITS. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).
	Attenuation of lateral propagating light in sea ice measured with an artificial lamp in winter Arctic 期刊论文 OAI收割 COLD REGIONS SCIENCE AND TECHNOLOGY, 2010, 卷号: 61, 期号: 1, 页码: 6-12 作者: Zhao, J. -P.; Li, T.; Barber, D.; Ren, J-P; Pucko, M. 收藏 \| 浏览/下载：33/0 \| 提交时间：2015/07/20 Lateral propagating light Optical attenuation coefficient Artificial lamp Arctic Sea ice
	Far-field focusing of laser beam based on digital image processing techniques (EI CONFERENCE) 会议论文 OAI收割 Optoelectronic Imaging and Multimedia Technology, October 18, 2010 - October 20, 2010, Beijing, China 作者: Zhao S.; Tian Y.-Z.; Liu L.-S.; Guo J.; Zhang H.-Y. 收藏 \| 浏览/下载：28/0 \| 提交时间：2013/03/25 In order to lead the laser beam transmit in the atmosphere convergently an experiment of laser focus at the distance of 450m and 300m has been operated in the outdoor place. The actual manipulations are as follows: Firstly the laser was collimated by a beam expander then the near-parallel laser beam was transmitted with a Galileo telescope system and the distance between the concave lens and the convex lens can be tuned through a precise displacement platform so the focus of the system changed due to the tiny displacement of the concave lens. Secondly the average power of the laser spot can be measured using power meter the power is 47.67mW and the standard deviation is 0.67mW while the focal length is 450m. Thirdly the energy distribution was found through the laser beam analyzer. The spot images were saved using the beam analyzer then the saved image can be processed with Matlab software afterwards. The function named EDGE and Sobel operator was used in the pre-processing of the saved image then method of median filter was used in the course of image de-noising and 53H filter was adopted in the signal analysis. The diameter of laser spot was obtained by the method above the diameter is 5.56mm and the standard deviation is 0.24mm. The spot center excursion is 0.56mm it is 10.43% of the total diameter of the laser spot. At last the key factors of the energy dissipation in the focusing system can be summarized as follows: restriction of the diffraction limit attenuation in the atmosphere geometrical aberration of optical system and the diffraction limit and the geometrical aberration are significant in the three factors above so we can reduce the impact of the both factors during the design of optical system. The reliable referenced data of the system design can be acquired through the primary experiment research. 2010 SPIE.
	Linearity measurement for image-intensified CCD (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: Zhang L.; Zhao Y.; Zhao Y.; Zhao Y.; Yan F. 收藏 \| 浏览/下载：34/0 \| 提交时间：2013/03/25 To the characteristic of the ultraviolet CCD (UV ICCD) technique of the linearity measurement of the UV ICCD camera is studied based on the theory of radiometry. Approach of linearity measurement is discussed and a kind of measurement system of the UV ICCD has been developed based on the method of neutral density filter. It is very important that the transmittance of the filter is independent of the wavelength in the method of neutral density filter. Black metal screen mesh with different transmittance is used in our system and calibration of the filters' transmittance in different working positions has been done. Meanwhile to assure the uniform of the received radiation on the target of the detector at any test points an integrating sphere is placed behind the neutral filter to balance light. The whole measurement system mainly consists of a deuterium lamp with high stabilization the attenuation film with transmission integrating sphere optical guide and electro-shift platform. Auto control is realized via special software during the test. With this instrument the linearity of the UV ICCD was measured. Experimental results show that the nonlinearity of the UV ICCD under fixed-gain is less than 2% and the uncertainty of measurement system is less than 4%. 2010 Copyright SPIE - The International Society for Optical Engineering.
	Electrically-controlled near-infrared chiroptical switching of enantiomeric dinuclear ruthenium complexes 期刊论文 OAI收割 chemical communications, 2009, 期号: 12, 页码: 1529-1531 Li D; Wang ZY; Ma DG 收藏 \| 浏览/下载：267/76 \| 提交时间：2010/05/27 CIRCULAR-DICHROISM OPTICAL-PROPERTIES MOLECULAR SWITCHES BRIDGING LIGAND REDOX SWITCH ATTENUATION CRYSTALS
	Variation in downwelling diffuse attenuation coefficient in the northern South China Sea 期刊论文 OAI收割 CHINESE JOURNAL OF OCEANOLOGY AND LIMNOLOGY, 2008, 卷号: 26, 期号: 3, 页码: 323-333 Wang, GF; Cao, WX; Yang, DT; Xu, DZ 收藏 \| 浏览/下载：23/0 \| 提交时间：2011/07/03 the downwelling diffuse attenuation coefficient chlorophyll a bio-optical model the northern South China Sea
	基于傅里叶变换的光纤探头光谱特性校正方法的研究期刊论文 OAI收割光谱学与光谱分析, 2005, 卷号: 25, 期号: 4, 页码: 541, 543 孟宪江; 张铁强; 施伟杰; 申铉国收藏 \| 浏览/下载：1229/223 \| 提交时间：2009/09/18 傅里叶变换 optical fiber 校正方法 spectrum attenuation 光谱特性 Fourier transform 光纤探头光电检测系统校正函数光电倍增管输出电流校正效果光纤传导非线性衰减逆变换可见光测试
	Towards the improvement of attenuation range and response time of electrochromic polymer-based variable optical attenuators 期刊论文 OAI收割 OPTICAL MATERIALS, 2004, 卷号: 27, 期号: 2, 页码: 265-268 作者: Zhang, JD; Yu, HA; Wu, MG; Wang, ZY \| 收藏 \| 浏览/下载：14/0 \| 提交时间：2019/04/09 Electrolyte-doped Pedot Film Optical Attenuation Electrochromic Variable Optical Attenuator