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	Study on spectrograph for ionosphere: A broadband imaging instrument prototype for far-ultraviolet (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2011: Space Exploration Technologies and Applications, May 24, 2011 - May 26, 2011, Beijing, China 作者: Wang S.-R.; Lin G.-Y.; Yu L. 收藏 \| 浏览/下载：35/0 \| 提交时间：2013/03/25 Current research on space-based exploration for the ionosphere needs more advanced technologies. Because the spectral signals in the ionosphere distributing basically in the far-ultraviolet waveband are very weak. Usual spectrometer structures and detectors such as CCD can't receive enough information. Based on this principle of atmospheric sounding the imaging spectrometer prototype for ionosphere detection application was designed to solve the problem. This prototype consists of the telescope and the imaging spectrometer. The simple structure and small number of mirrors can help higher transmission efficiency be achieved and weak signals detection be implemented. The telescope is an off-axis parabolic mirror and the spectrometer is a modified Czerny-Turner spectral imaging system. Modified Czerny-Turner spectrometer contains a spherical mirror a fixed plane grating and a toroidal mirror. By adjusting the incident angle to the collimating mirror and using toroidal mirror coma and astigmatism were corrected well. We also optimize distances between the grating to the focusing mirror and the focusing mirror to the image plane to improve disadvantages of traditional Czerny-Turner structure. Designed results demonstrate that aberrations are substantially corrected and high image quality can be obtained in broad waveband. The photon counting Wedge-Strip-Anode detector with micro-channel planes as the receiving plane is accepted for the instrument prototype. The other photon counting 2-D detector responding well for weak light such as Cross-Delay line detector and MAMA detector can also be used for detection. The calibration and performances testing system is made of a vacuum system a deuterium lamp a monochrometer and the instrument prototype. Results obtained from the experiment show that the spectral resolution is 2.4 nm and the spatial resolution is 80 m. The other calibration experiments are running. The technology of the spectrometer prototype is important for the research and applications of ionosphere remote sensing. 2011 SPIE.
	Fabrication of high-efficiency ultraviolet blazed gratings by use of direct Ar2-CHF3 ion-beam etching through a rectangular photoresist mask (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2011: Sensor and Micromachined Optical Device Technologies, May 24, 2011 - May 26, 2011, Beijing, China Tan X. 收藏 \| 浏览/下载：25/0 \| 提交时间：2013/03/25 In ultraviolet spectroscopy groove irregularity and surface roughness of nanometer magnitude can cause a significant loss of diffraction efficiency. Therefore there is a constant need to improve the diffraction efficiency. A blazed grating can concentrate most of the light intensity into a desired diffraction order it is important to control the groove shape precisely so it is the optimum choice among gratings of different kinds of profile. As the operating wavelength of most UV spectral applications is less than 200 nm especially the blaze angle and the apical angle. We have presented a direct shaping method to fabricate EUV blazed gratings by using an ion-beam mixture of Ar+ and CHF2 +to etch K9 glass with a rectangular photoresist mask. With this method the required blaze angle is small we have succeeded in fabricating well-shaped UV blazed gratings with a 1200 line/mm groove density and 8.54 blaze angles and 1200 line/mm groove density and 11.68 blaze angles and the metrical efficiency is about 81% and 78%. The good performance of the gratings was verified by diffraction efficiency measurements. When one uses the etching model the conditions on the ion-beam grazing incident angle and the CHF3partial pressure should be noted. Besides since the etched groove shape depends on the aspect ratio of the photoresist mask ridge if we wish to fabricate larger gratings with this method we must improve the uniformity of the photoresist mask before ion-beam etching. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).
	Rigorous vector analysis of diffractive microlens by using of finitedifference time-domain method (EI CONFERENCE) 会议论文 OAI收割 2009 International Conference on Optical Instruments and Technology, OIT 2009, October 19, 2009 - October 22, 2009, Shanghai, China 作者: Liu Y.; Liu H.; Liu H.; Liu H.; Liu Y. 收藏 \| 浏览/下载：31/0 \| 提交时间：2013/03/25 We use finite difference time domain (FDFD) method as rigorous vector analysis model to simulate the focusing process of diffractive microlens (DML). Differing with most analysis model which the near field distributions are calculated by FDTD and then far field are obtained by using of propagation method we obtain the fields in whole computational space by using of FDTD only. The advantages are that all the results are vector based and the computational time is saved greatly. In this paper we present two methods to obtain wave amplitude one is comparison method and the other is integral method. Depending on wave amplitude in the whole computational space one can conveniently obtain distributions of electric field intensity and calculate the time-average Poynting vector. We also present the formulation for calculating diffractive efficiency of DML based on time-average Poynting vector which denotes energy flow. As demonstration a DML is analyzed by using of these algorithms. The time depended graphic results of FDTD show the process of wave propagation. The distribution of electric field intensity illustrates the focusing of the normal incident light. The focus pattern in the focal plane is also show. The diffractive efficiency of the DML is calculated by using of the energy flow method in this paper. The results show the high accuracy and efficiency of the model. 2009 SPIE.
	注入锁定激光器的边带锁频技术稳频系统优化分析期刊论文 OAI收割光子学报, 2008, 卷号: 37, 期号: 9, 页码: 1748, 1752 孙旭涛; 陈卫标收藏 \| 浏览/下载：1684/200 \| 提交时间：2009/09/18 单频激光 Error signals 注入锁定 Frequency noises 稳频 Frequency stabilization PDH技术 Frequency stabilizations Incident light Injection-locked Narrow lines PDH technique Single frequency laser Temperature fluctuations Theoretical models
	Research on method of measuring the time of remote explosion point (EI CONFERENCE) 会议论文 OAI收割 27th International Congress on High-Speed Photography and Photonics, September 17, 2006 - September 22, 2006, Xi'an, China 作者: Zhou J.; Fu Y. 收藏 \| 浏览/下载：21/0 \| 提交时间：2013/03/25 The time when the bomb explodes is one of the most important indexes to appraise the test. According to the principles concerned with explosion radiation the principle of measuring the time of remote explosion point and composition of measuring system is introduced. Use CCD to record the explosion radiation DSP to process and record the high-capacity high-speed video signals and convert the exploding process examined by floating amplifier into digital signals. Besides the article analyzes the composing and structural design of the log's optical system principle of electric control and floating amplifier dynamic range of the system power analysis of the incident light and how to improve the accuracy of measurement in great detail.
	Optical thin films for high power LD-pumped Nd:YVO4 457nm blue laser (EI CONFERENCE) 会议论文 OAI收割 ICO20: Optical Design and Fabrication, August 21, 2005 - August 26, 2005, Changchun, China Bu Y.; Zheng Q.; Xue Q.; Qian L. 收藏 \| 浏览/下载：21/0 \| 提交时间：2013/03/25 The expanding field of LD-pumped solid state lasers forms an extraordinary challenge for developing the optical coatings. Optical thin films for LD-pumped Nd:YVO4/LBO blue laser at 457nm was presented in this paper based on lower gain laser line action theory including spectral beam dividers and doubling antireflecting multilayer coatings. To achieve 914nm laser action and 457nm blue light high output power the coating specifications of laser resonator was analyzed. The transmittance/reflectance spectrum request was effectively separated by adopting high tuned radio stack simultaneously the spectrum request was reasonably distributed on the two resonator facet reflectivity for restrain the other laser lines such as1064nm and1342nm. The dielectric high reflective laser mirror and antireflecting coatings for 457nm laser were manufactured by double ion beam sputtering technique which is controlled by a time-power monitoring. Using type-I critical phase-matching LBO crystal 457nm blue laser is obtained by 914nm intracavity frequency doubling. The maximum laser output power of 1.5W is obtained when incident pump laser of 15W is used.