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	An Instrument for In Situ Measuring the Volume Scattering Function of Water: Design, Calibration and Primary Experiments 期刊论文 OAI收割 SENSORS, 2012, 卷号: 12, 期号: 4, 页码: 4514-4533 Li, C; Cao, WX; Yu, J; Ke, TC; Lu, GX; Yang, YZ; Guo, CY 收藏 \| 浏览/下载：59/0 \| 提交时间：2013/08/28 ocean optics scattering measurements array detection calibration test in-field measurement scattering volume optical radiometric calibration
	Research on radiometric calibration of interline transfer CCD camera based on TDI working mode (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: 收藏 \| 浏览/下载：34/0 \| 提交时间：2013/03/25 Interline transfer CCD camera can be designed to work in time delay and integration mode similar to TDI CCD to obtain higher responsivity and spatial resolution under poor illumination condition. However it was found that outputs of some pixels were much lower than others' as interline transfer CCD camera work in TDI mode in laboratory radiometric calibration experiments. As a result photo response non-uniformity(PRNU) and signal noise ratio(SNR) of the system turned for the worse. This phenomenon's mechanism was analyzed and improved PRNU and SNR algorithms of interline transfer CCD camera were advanced to solve this problem. In this way TDI stage was used as a variant in PRNU and SNR algorithms and system performance was improved observably with few influences on use. In validation experiments the improved algorithms was applied in radiometric calibration of a camera with KAI-0340s as detector. Results of validation experiments proved that the improved algorithms could effectively improve SNR and lower PRNU of the system. At the same time characteristic of the system could be reflected better. As working in 16 TDI stages PRUN was reduced from 2.25% to 0.82% and SNR was improved about 2%. 2010 Copyright SPIE - The International Society for Optical Engineering.
	Research on the laboratory radiometric calibration of the thermal imager (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: Wang J.; Liu Y.; Liu Y.; Liu Y.; Sun Q. 收藏 \| 浏览/下载：32/0 \| 提交时间：2013/03/25 The radiometric calibration of the thermal imager was investigated to build the relationship between the input radiance and the digital output to realize the temperature measurement. The radiometric calibration was implemented in the State Key Laboratory of Applied Optics. A standard black body source was served as radiation source. The response of the thermal imager to the input radiance was tested for different gains. The experimental results show that the average grey level of the output imaging is linear dependence of the input radiance. Because the radiance in the receiving wave range of the thermal imager is linear with the black body's temperature based on Planck's law of radiation the average grey level of the output image is also linear with the black body's temperature after fitting a curve to the experiment data points. Then the relationship of the response and the gain was studied when the black body's temperature kept constant. The preliminary analysis of calibration data shows that the response of the thermal imager is linear and the average grey value of the image is directly proportion to the gain. According to the experimental results the reference gains and the dynamic range of temperature measurement were obtained. Finally the uncertainty influencing the calibration results was analyzed the analysis shows the maximal uncertainty is 5.2% which can meet the calibration requirement less than 10%. 2010 Copyright SPIE - The International Society for Optical Engineering.
	Level 0 and level 1 data processing for a type of hyper-spectral imager (EI CONFERENCE) 会议论文 OAI收割 2009 International Conference on Optical Instruments and Technology, OIT 2009, October 19, 2009 - October 21, 2009, Shanghai, China Li X.; Yan C. 收藏 \| 浏览/下载：80/0 \| 提交时间：2013/03/25 Hyper-spectral imaging (HSI) is a kind of optical remote sensor that can simultaneously obtain spatial and spectral information of ground targets. We are now designing a data processing system for a type of space-borne push-broom HSI then it performs radiometric and spectral calibration based on the ground calibration results and onboard calibration collection. The detailed algorithms for bad pixel replacement which has 128 spectral channels covering the spectral range from 400nm to 2500nm. With its large amount of spectral channels radiometric and spectral calibration were presented. After processing the HSI collects large volume of spectral imaging data need to be efficiently and accurately processed and calibrated. In this paper the digital numbers downlinked from the spacecraft can be converted into at-sensor absolute spectral radiance of ground targets the detailed Level 0 and Level 1 data processing steps for the HSI were presented. The Level 0 processing refers to a set of tasks performed on the data downlinked from the spacecraft thus providing accurate quantified spectral imaging data for various applications. 2009 SPIE. including decoding to extract science data separating the science data into files corresponding to different tasks (e.g. ground imaging dark imaging and onboard calibration) checking data integrity and instrument settings data format conversion and Level 0 files creation. The Level 1 processing performs several steps on Level 0 data. Firstly it corrects the image artifacts (mostly the SWIR smear effect) subtracts the dark background and performs the bad pixel replacement according to the prelaunch measurement