红外系统自身热辐射对探测系统性能的影响研究

发布时间：2018-05-15 11:32

  本文选题：红外探测系统 + 自身热辐射　； 参考：《中国科学院大学(中国科学院光电技术研究所)》2017年硕士论文

【摘要】：在空间、空中等特殊低温环境中,红外系统接受到的外部背景辐射大幅减小,系统自身热辐射的影响则可能会凸显出来。系统自身热辐射会导致探测像面的辐射量噪声变大,系统的动态范围缩小,非均匀性变差等现象。本论文通过对光学系统自身热辐射的分析,基于实验测量光学系统自身热辐射在像面处的大小,得到光学系统的等效黑体辐射温度,并分析了自身热辐射对探测系统的相关性能指标的影响,为控制自身热辐射以达到探测性能指标提供参考及意见。本文首先对影响光学系统自身热辐射的因素进行分析,介绍并比较了自身热辐射的评估方式,详细阐述了三种自身热辐射的计算方法:仿真测试、辐射标定测试法,等效黑体测试法。其次,介绍自身热辐射的测试实验平台的组成、工作原理、仪器选择要求等,并对背景模拟板的发射率进行测试,进行光学系统的调试,为后期实验做了重要的铺垫。然后,进行仿真和测试,用上述三种自身热辐射研究方法,对某光学系统的等效黑体辐射温度进行了评估,并进行了背景模拟板的温度变化引起的辐射强度变化分析,探测器的稳定性分析,线性拟合不确定度分析等。最后分析了探测系统的噪声组成及定性分析了光学系统自身热辐射对探测系统的信噪比影响,介绍了各项探测性能指标的计算方法,并通过实验定量得到和比较了不同反射率红外光学探测系统的性能表现,研究了光学系统在不同的局部温度变化速率下性能的变化情况,也研究了光学系统制冷到-43℃状态下的探测系统性能表现,结合实验结果又分析了光学系统各状态下自身热辐射对性能影响。通过对某光学系统自身热辐射的研究,得到其自身热辐射在探测像面上的量级为10~(-5)W/cm~2,结果说明其对系统的NETD、系统NEFD、探测距离有较大的影响。
[Abstract]:In the special low temperature environment such as space and air, the external background radiation received by infrared system is greatly reduced, and the influence of the system's own thermal radiation may be highlighted. The thermal radiation of the system itself will cause the noise of the detected image surface to increase, the dynamic range of the system to narrow, and the inhomogeneity to become worse. In this paper, the equivalent blackbody radiation temperature of the optical system is obtained by analyzing the thermal radiation of the optical system and measuring the size of the thermal radiation of the optical system at the image plane based on the experiment. The influence of self-heat radiation on the related performance index of the detection system is analyzed, which provides a reference and advice for controlling the self-thermal radiation to reach the detection performance index. In this paper, the factors affecting the thermal radiation of the optical system are analyzed, and the evaluation methods of the self-thermal radiation are introduced and compared, and three calculation methods of the self-thermal radiation are described in detail: simulation test, radiation calibration test method. Equivalent blackbody test method. Secondly, it introduces the composition, working principle, instrument selection requirements of its own thermal radiation test platform, and tests the emissivity of the background analogue board, carries on the optical system debugging, and makes the important cushion for the later experiment. Then, the equivalent blackbody radiation temperature of an optical system is evaluated by using the three self-heat radiation research methods mentioned above, and the radiation intensity change caused by the temperature change of the background analog plate is analyzed. Stability analysis, linear fitting uncertainty analysis and so on. Finally, the noise composition of the detection system and the influence of the thermal radiation of the optical system on the signal-to-noise ratio of the detection system are analyzed qualitatively, and the calculation methods of each detection performance index are introduced. The performance of infrared optical detection system with different reflectivity is quantitatively obtained and compared by experiments. The performance of the optical system under different local temperature changing rates is studied. The performance of the detection system is also studied when the optical system is cooled to -43 鈩，

本文编号：1892288