Research On The Influence Of The Self-thermal Radiation On The Performance Of Infrared Detection System

In the space or air special environment,the external background radiation under the infrared detection system is significant small,and self-thermal radiation of system may be much larger than background radiation.The system's thermal radiation will lead to detection of image surface radiation noise and dynamic range is narrow,heterogeneity is poor.In the article,we analyze the thermal radiation of optical system,measure the self-thermal radiation on image plane,calculate the equivalent blackbody radiation temperature of optical system,analyze the effect of self-thermal radiation on the related performance indicators for detection system,in order to provide some the reference and advice for control the self-thermal and achieve detection performance.Firstly,in this article analyze the factors influencing the thermal radiation of the optical system,and introduce and compare the evaluation for the thermal radiation,elaborate the three test method of thermal radiation in detail,the calculation method of simulation,the test method of radiation calibration,equivalent blackbody test method.Secondly,we introduce the composition,working principle and instrument selection requirements of the experiment platform to test self-thermal radiation,and test the emissivity of the background Simulation board,and debug the optical system to prepare for later test experiment.And then,we conduct simulation and test,evaluate equivalent blackbody radiation temperature of the one optical system by using three research method.Temperature change bring radiation intensity change of background simulation board,the stability analysis of detector,and the uncertainty of linear fitting were analyzed.In the end,we analyze the composition of the noise of the detection system,qualitatively analyze the thermal radiation for the optical system effect on the signalto-noise ratio of detection system,introduce the calculation method of the detection performance indexes,quantitative obtained the results two different reflectivity of the infrared optical detection system through experiment.The performance of the optical system under different local temperature and the performance of the optical system at-43? is studied on.Based on the experiment results,we analyze the influence of the self-thermal radiation for optical system at different condition on the performance of detection system.Based on the study of the self-thermal radiation of the one optical system,the magnitude of the radiation in the image plane is obtained,is 10^-5W/cm²,and the results show that it has a great influence on the NETD,NEFD and the detection range of the infrared detection system.