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	A practical algorithm for estimating surface soil moisture using combined optical and thermal infrared data 期刊论文 iSwitch采集 International journal of applied earth observation and geoinformation, 2016, 卷号: 52, 页码: 338-348 作者: Leng, Pei; Song, Xiaoning; Duan, Si-Bo; Li, Zhao-Liang 收藏 \| 浏览/下载：50/0 \| 提交时间：2019/05/09 Surface soil moisture (ssm) Historical meteorological records Daily maximum solar radiation Optical and thermal infrared
	A practical algorithm for estimating surface soil moisture using combined optical and thermal infrared data SCI/SSCI论文 OAI收割 2016 作者: Leng P.; Song, X. N.; Duan, S. B.; Li, Z. L. \| 收藏 \| 浏览/下载：22/0 \| 提交时间：2017/11/09 Surface soil moisture (SSM) Historical meteorological records Daily maximum solar radiation Optical and thermal infrared remotely-sensed data amsr-e emissivity retrieval hydrological model ers scatterometer satellite data temperature scale index water
	Design of reimaging F/1.0 long-wavelength infrared optical 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 X.; Zhang X.; Zhang X. 收藏 \| 浏览/下载：36/0 \| 提交时间：2013/03/25 A reimaging F/1.0 long-wavelength infrared optical system is proposed. The design has a flexible opto-mechanical layout. The design process is as follows. Firstly the catadioptric reimaging system consists of two reflecting mirrors and a relay lenses. Two reflecting mirrors make up of the first imaging system and are therefore free of chromatic aberrations while low dispersion lenses were used in the reimaging system so the optical system do not need achromatic design for a high image quality. Then to correct high-order aberrations resulting from large relative aperture more parameters need to be used with aspheric or diffractive surfaces due to modern optic technology development. Here aspheric is selected for easily manufacture. Finally the design is completed with the help of ZEMAX software. The effective focal length of the objective is 120mm and the field of view (FOV) is 4. The simulated final design shows adequate image quality and the modulation transfer function (MTF) is close to diffraction limit. The effect of the surrounding environmental temperature is analyzed using the concept of thermal defocusing and the thermal compensation is discussed. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).
	Thermal difference analysis and athermalization design of infrared optical system (EI CONFERENCE) 会议论文 OAI收割 Optical Design and Testing IV, October 18, 2010 - October 20, 2010, Beijing, China 作者: Zhang X.; Zhang X.; Zhang X. 收藏 \| 浏览/下载：32/0 \| 提交时间：2013/03/25 When infrared optical system works in a large temperature range the thermal effect of optical lens and optical tube will produce image plane shift and lead to imaging quality deterioration. In order to eliminate the thermal aberration the athermalization design principles of infrared optical system were introduced and some commonly used methods of thermal difference compensation were described. Proceeding from single lens the thermal difference caused by temperature changing was analyzed and the relationship between temperature and focus shift was obtained. Considering optical tube thermal expansion a set of equations to estimate the thermal difference of lens group was given. Finally an infrared optical imaging system that can work under the temperature range of -40C to 60C was design according to athermal technique in which a new mechanical passive temperature compensation was proposed. Through simulation the athermalization design could make imaging plane shift the smallest. The simulation results coincided with the theoretical formula and the design had reference value in engineering. 2010 Copyright SPIE - The International Society for Optical Engineering.
	Athermal design of hybrid refractive/harmonic diffractive optical system for far-infrared multi-band (EI CONFERENCE) 会议论文 OAI收割 4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies, November 19, 2008 - November 21, 2008, Chengdu, China 作者: Liu Y.; Liu Y.; Zhang H.; Zhang H.; Sun Q. 收藏 \| 浏览/下载：29/0 \| 提交时间：2013/03/25 In order to get enough information about the target avoid big chromatic aberration as a result of wide spectrum and the complexity of optical system and adapt different special environment temperature a hybrid refractive/harmonic diffractive optical system in far-infrared multi-band is described in the paper. This diffractive optical system has been designed an athermalized multi-band imaging system with harmonic diffractive element in 15-50m spectrum based on larger 1dispersion capability and particular thermal dispersive power of harmonic diffractive element. Then at the temperature range from 0C to 40C this design can simultaneously meet with all requirements of the imaging system in five harmonic wave bands including15.8-16.2m 18.5-20m 23-25m 30.5-33.5m and 46-50m. In each harmonic wave band the magnification changes as a function of wavelength which creates image registration error. To compensate this shortcoming a zoom optical system is designed with three lenses by means of optical two- component method. The design results show that the hybrid refractive/harmonic diffractive optical system can realize athermalized and achromatic design and the zoom optical system makes half image height at 3.53mm in every harmonic wave band and still realizes aberration compensation action. In the five harmonic wave bands each optical transfer function approaches the diffraction limit at ambient temperature range of 0C to 40C. Finally the system realizes the requirements of portability mini-type and ease for fabrication. 2009 SPIE.
	Design of the infrared dual-band athermalized optical system based on HDE (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2009: Advances in Infrared Imaging and Applications, June 17, 2009 - June 19, 2009, Beijing, China 作者: Zhang L.; Sun Q.; Wang H.; Wang H.; Wang H. 收藏 \| 浏览/下载：97/0 \| 提交时间：2013/03/25 A dual-band infrared optical system adopting an uncooled LW infrared detector and a cooled MW infrared detector is designed and manufactured while in the LW IR band the F/# is 1 and the focal length is 114 mm based on the athermal ability and special diffractive properties of harmonic diffractive elements. The design shows in the MW IR band the F/# is 2 and the focal length is 72 mm for the temperature range -40 70 the MTF value is over 0.5 at 10 lp/mm. Finite element method is applied to the opto-mechanic structure of the system for thermal analysis for the temperature range -40C 70C the MTF value is over 0.4 at 20 lp/mm which confirms the imaging ability of the system in a wide temperature range. 2009 SPIE.