一种多谱段红外成像光学系统设计

Design of a multispectral infrared imaging optical system

为提高红外远程目标探测识别能力,除了增加焦距和有效口径等传统措施,还需要进一步获取目标的多谱段信息,从而将具备不同辐射特性的目标和背景区别开。本文提出了一种采用多谱段分区红外探测器和棱镜旋转像移成像光学系统,将同一目标的红外辐射能量会聚到探测器不同谱段区域进行成像,从而获取同一目标的多谱段成像信息。该系统采用同轴反射式光学系统,具备8个不同谱段分区的两支红外探测器,通过棱镜旋转实现同一目标的8个谱段信息获取。系统焦距520mm,有效口径200mm,F数为26。光学系统结构紧凑,棱镜旋转与探测器成像实时对应,不存在成像延迟和像旋,具有口径大、焦距长、谱段多等特点,满足系统高分辨率、长作用距离、多谱段信息获取等要求。

In order to improve long range infrared target detection and recognition,besides the traditional measures such as increasing the focal length and effective aperture,it is necessary to further obtain the multi spectral information of the target,so as to distinguish the target with different radiation characteristics from the background.In this paper,a multispectral infrared detector and prism rotating image shift imaging optical system is proposed.The infrared radiation energy of the same target is converged to different spectral regions of the detector for imaging,thus obtain multispectral imaging information of the same target.The system adopts coaxial reflective optics,which has two infrared detectors with 8 different spectral sections.The information of 8 spectral sections of the same target can be obtained by prism rotation.The focal length of the system is 520mm,the effective aperture is 200mm,and the F number is 2.6.The optical structure of the system is compact,the prism rotation corresponds to the detector imaging in real time,there is no imaging delay and image rotation,and it has the characteristics of large aperture,long focal length,multiple spectral segments,etc.,which meets the system requirements of high resolution,long operating distance and multi spectral information acquisition.