红外双波段光学系统被动式消热差设计

为提高红外光学系统的目标探测识别能力,增强其温度适应能力,在分析红外材料在中波和长波红外波段的色差与热差特性的基础上,根据系统光焦度分配、双波段轴向消色差和双波段消热差等要求,利用红外色差图合理选择光学材料组合,设计了一款中波和长波红外双波段消热差系统,系统采用非制冷探测器,工作波段为3~5 m和8~12 m,由4片透镜组成,焦距为50 mm,相对空间为1:1.25,全视场角为14,总长67.9 mm。设计结果表明:在温度范围-50~60 ℃范围内,在空间频率为17 lp/mm处,系统在中波和长波波段的MTF值均大于0.4,表明系统有较强的温度适应性。

Passive athermal design of dual-band infrared optical system

In order to improve the target detection and recognition ability and enhance the environment adaptability of infrared optical system, thermal and chromatic properties of infrared optical materials in MLIR and LWIR were analyzed, acoording to the requirements of optical power distribution, axial achromatic aberration and athermal aberration in the dual infrared band, properly lens materials were choosed based on the infrared chromatic diagram. And a dual-band infrared athermal optical system was designed. The system based on no cooled staring detector, the wavelength spectrum was 3-5 m and 8-12 m, The system consisted of four lenses, the effective focal length was 50 mm, the relative aperture was 1:1.25, the field view was 14 and the total optical focal length was just 67.9 mm. The result shows that between -50-60 ℃ and at the modulation transform function of 17 lp/mm is greater than 0.4 both in MWIR and LWIR, which prove that the system can work correctly at a large temperature range.