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Infrared radiation measurement based on simplified calibration method 会议论文
27th Conference of Spacecraft TT and C Technology, November 9, 2014 - November 12, 2014, Guangzhou, China
Chang S.; Li M.; Zhang Y.
收藏  |  浏览/下载:13/0  |  提交时间:2015/04/27
Study of jamming of the frequency modulation infrared seekers 会议论文
Conference Location, 2013
Qian F.; Guo J.; Shao J. F.; Wang T. F.
收藏  |  浏览/下载:8/0  |  提交时间:2014/05/22
Mechanism Design of Continuous infrared Lens 会议论文
Conference Location, 2013
Su Y. Q.; Zhang J. X.; Lv T. Y.; Yang F.; Wang F. G.
收藏  |  浏览/下载:17/0  |  提交时间:2014/05/22
Comparison of radiation temperature measurement precision between middlewave and longwave thermal-imaging systems (EI CONFERENCE) 会议论文
2012 International Conference on Optoelectronics and Microelectronics, ICOM 2012, August 23, 2012 - August 25, 2012, Changchun, China
Sun Z.; Zhu W.
收藏  |  浏览/下载:15/0  |  提交时间:2013/03/25
A comparison study on temperature measurement precision between middlewave 3-5m and longwave 8-12m measuring thermal imaging systems has been conducted. The study was limited to systems working in indoor conditions and the target's temperature is in the range of 270K900K. First  the Disturb Resisting Function (DRF) of infrared systems is deduced. On the base of DRF curve  we find that the middlewave infrared system get the smaller influences under the same size disturb compared with the longwave system. A theory of the influence of target's physical characteristic and measurement conditions on the accuracy of temperature measurements has been developed. On the basis of the developed formulas an analysis of the influence of signal disturbances (because of incorrectly assumed emissivity  limited transmittance of the atmosphere  radiation reflected by the object and shift of optics radiation) on the accuracy of temperature measurement has been made. It has been found that the middlewave systems in typical temperature range offer generally better accuracy in temperature measurement than the longwave ones do. 2012 IEEE.  
Research of ballistic missile early warning system (EI CONFERENCE) 会议论文
2nd International Conference on Advanced Engineering Materials and Technology, AEMT 2012, July 6, 2012 - July 8, 2012, Zhuhai, China
Zhang M.-H.; Zhang Y.-Y.
收藏  |  浏览/下载:23/0  |  提交时间:2013/03/25
To develop a lift early warning infrared device  as a part of land or boat (ship) early warning system  the system has the ability to target pre-discovery and instructions invasion. Methods: In support of distant air situation  alerts the enemy aircraft  missiles and other long-range goals  obtain the target type and preliminary judgment of grade  deliver the alarm information to the command system. The infrared alarm device detects the target's own infrared radiation passively  alarms the incoming targets at low altitude and low altitude remote  when radar and other equipment is out of work. Results: The accuracy of entire system reached 20 according the analysis. Conclusions: The device has a full range of complex background  with high sensitivity  high resolution  anti-jamming  fast response time and other characteristics. (2012) Trans Tech Publications  Switzerland.  
Evaluation of the operating range for ground-based infrared imaging tracking system (EI CONFERENCE) 会议论文
International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Infrared Imaging and Applications, May 24, 2011 - May 24, 2011, Beijing, China
Zhang B.; Zhang Z.-D.; Zhang S.-M.
收藏  |  浏览/下载:33/0  |  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).  
Infrared signature measurement of targets accounting for atmospheric attenuation (EI CONFERENCE) 会议论文
2010 International Conference on Computer, Mechatronics, Control and Electronic Engineering, CMCE 2010, August 24, 2010 - August 26, 2010, Changchun, China
Yang C.-Y.; Cao L.-H.; Zhang J.-P.; Lu M.
收藏  |  浏览/下载:15/0  |  提交时间:2013/03/25
Infrared radiation signature measurement of targets is one of important ways for target signature acquirement and target recognition. When measuring the infrared signature of a target in the atmosphere  molecules and aerosol particles in the atmosphere would attenuate the infrared radiation from the target  and at the same time  the air path radiation would be added to the target radiation. Therefore  in order to obtain the intrinsic infrared radiation of the target  it is necessary to perform atmospheric correction in the process of target radiation inversion. A model for target radiation measurement and inversion was established  and precision analysis on the model was given. A longwave infrared camera was used to perform infrared signature measurement experiment on an ISDC extended-area blackbody. Based on atmospheric parameters  the atmospheric transmittance and the air path radiation between the blackbody target and the camera were calculated by using the MODTRAN software  for use in atmospheric correction in the target radiation inversion process. The experimental results showed that radiation inversion precisions were about 7.3%9.3%. Additionally  inversion precision will improve as target temperature rises. 2010 IEEE.  
Ground-based measurement of the space object temperature (EI CONFERENCE) 会议论文
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Large Mirrors and Telescopes, April 26, 2010 - April 29, 2010, Dalian, China
Wang G.-Q.; Wu Y.-H.; Wang J.-L.; Zhao J.-Y.
收藏  |  浏览/下载:34/0  |  提交时间:2013/03/25
Multi-band IR data of the space object can be used in the fields of object identification and space surveillance. The radiation characteristics of the object can be obtained by analyzing these data. These characteristics include temperature  area  emissivity  absorptivity  reflectivity  and temporal trends. The infrared radiation temperature of the space object is an important characteristic from which the object's working state in orbit can be judged. We apply the method of measuring the spectral distribution of the object and fit the data to the Planck formula to determine the temperature. In order to improve the precision of measuring temperature on the space object  we optimize the centric wavelength and the bandwidth effectively. Also  we use a simple program to implement temperature measurement. 2010 Copyright SPIE - The International Society for Optical Engineering.  
Development and radiance calibration of three-waveband camera (EI CONFERENCE) 会议论文
International Symposium on Photonics and Optoelectronics, SOPO 2010, June 19, 2010 - June 21, 2010, Chengdu, China
Lu Z.; Sun Q.; Wang J.; Lu Z.; Liu Y.
收藏  |  浏览/下载:22/0  |  提交时间:2013/03/25
An imaging system with three-waveband sharing one lens and an area CCD was developed. By rotating different filters into the beam path  the required waveband was selected. The optical system which can image in ultraviolet  visible and near infrared region was designed and the signal collecting system was integrated. The optical design and system integration have some advantages such as low cost  small size and light in weight. To obtain a high imaging quality  the radiation calibration is carried out in order to establish the relation between the average grey level of output image and the input radiance from the integrating sphere. According to the calibration data in experiments  the radiation dynamic range and the best working point of the system are determined. The experiment result shows that the dynamic range of the image system is maximal when the exposure time is 8ms in ultraviolet  0.5ms in visible and 0.125ms in near infrared region. 2010 IEEE.  
Experiments of second harmonic generation output in pulsed TEA CO 2 laser (EI CONFERENCE) 会议论文
High-Power Lasers and Applications V, October 18, 2010 - October 19, 2010, Beijing, China
Guo R.; Li D.
收藏  |  浏览/下载:40/0  |  提交时间:2013/03/25
It is always the hot subject to realize the output of high-power laser in the range of 3-5m wavelength. This rang of wave band has greatly important applications in military because it located in the atmosphere window. Generally there are two ways to obtain this range of laser wavelength. One way is through optical parameter oscillation (OPO) from shorter laser wavelength and the other is through second harmonic generation (SHG) from longer laser wavelength. Firstly  the comparison between tow nonlinear crystals ZnGeP2 and AgGaSe2 is conducted for their nonlinear coefficient and damaging threshold in theory. The theoretical results show that the crystal AgGaSe 2 is more suitable for the SHG of pulsed TEA CO2 laser. When using pulsed TEA CO2 laser with wavelength of 9.3m to pumping AgGaSe2 SHG crystal  the wavelength of 4.65m is obtained. In the condition of repetition rate 100Hz  the upmost output power of single pulse is up to level of 1W  which corresponding efficiency of SHG is about 6%. The experimental results show that the polarization of laser beam has greatly influence on the SHG output of the crystal. Under the radiation of 3MW/cm 2 from fundamental wave and the right position for maximal SHG output in the crystal  when polarization of laser beam rotates 4.5  the SHG output of energy decrease about 30%. The research of this paper will make a foundation for further development of mid-infrared laser. 2010 Copyright SPIE - The International Society for Optical Engineering.  


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