元件缺陷对红外光学系统杂散辐射特性的影响

发布时间：2018-02-21 23:20

本文关键词： 杂散辐射光学元件缺陷有效发射率　出处：《红外与激光工程》2017年01期 　论文类型：期刊论文

【摘要】：针对红外光学系统元件表面缺陷问题,基于米氏散射理论定量分析了不同疵病等级光学元件表面散射特性,讨论了光学元件表面双向散射分布函数(BSDF)的变化规律,进而建立光学元件不同疵病等级的散射模型。在此基础上,以双子望远镜系统为例,利用ASAP光学分析软件对其主镜在不同疵病等级的情况下,到达探测器像面上的系统自身热辐射通量及其分布进行了仿真计算,并根据有效发射率的定义,对系统杂散辐射性能进行了定量评价。研究分析发现:光学元件不同疵病等级不仅会造成系统杂散辐射特性及其在探测器像面上的辐射通量分布发生变化,而且还会导致其有效发射率发生变化。对主镜疵病等级分别为0、I-10、I-20、I-30、II和III的情况,计算得到系统有效发射率分别为2.19%、2.34%、2.46%、2.59%、2.72%和3.08%。由此可见,随着疵病等级的增加,系统杂散辐射性能逐渐降低。实际工作中,必须严格控制光学元件表面疵病等级。
[Abstract]:In order to solve the problem of surface defects in infrared optical system, the surface scattering characteristics of optical elements with different defect grades are quantitatively analyzed based on Michelson scattering theory, and the variation of BSDF is discussed. Then the scattering model of optical elements with different defect grades is established. On the basis of this model, the primary mirror is analyzed by using ASAP optical analysis software, taking the binocular system as an example. The heat radiation flux and its distribution of the system arriving on the image plane of the detector are simulated and calculated, and the effective emissivity is defined according to the definition of the effective emissivity. The quantitative evaluation of the stray radiation performance of the system is carried out. It is found that the different defect grades of the optical elements will not only cause the system stray radiation characteristics and the radiation flux distribution on the detector image plane to change. The effective emissivity of the primary mirror is calculated to be 2.19, 2.34 and 2.59%, respectively. It can be seen that with the increase of the defect grade, the effective emissivity of the primary mirror is 2.72% and 3.08%, respectively, when the primary mirror defect grade is 0 ~ (10) and I-20 ~ (20) I ~ (30), respectively, and the effective emissivity of the system is calculated to be 2.19% and 3.08%, respectively. The stray radiation performance of the system decreases gradually. In practice, the surface defects of optical components must be strictly controlled.
【作者单位】：四川大学电子信息学院;
【基金】：科技部创新人才推进计划重点领域创新团队资助(2014RA4051) 四川省教育厅创新团队计划资助项目(13Td0048)
【分类号】：TN216

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