摘要
利用折/衍混合透镜实现了超宽温度范围内的光学被动式消热差设计,系统工作波段为8～12μm,全视场角为9.15°,焦距为100 mm,相对孔径为1/1.5,总长为128 mm,后工作距为10.5 mm。使用了锗和硒化锌两种材料,采用三片透镜,衍射面和偶次非球面的引入,不但能够消除热差,而且使得结构简单、轻量化,很好地提高了成像质量。设计结果表明:在-80～160℃温度范围内,空间频率为12.5 lp/mm处,各个温度下的MTF值均大于0.6,接近于衍射极限,成像质量良好,实现了消热差设计。该系统适用于像元尺寸为40μm,像元数为320×240的非制冷红外焦平面阵列探测器。
Hybrid refractive-diffractive design offers a new approach for athermalization design in wide temperature range. In this paper, the working wavelength was in 8-12μm; the full field of view was 9.15°; the efficient focal length （EFL） was 100 mm; the relative aperture was 1： 1.5; the total optical length was 128 mm and the back focal length （BFL） was 10.5 mm. The system was designed with three lenses and two kinds of material--Ge and ZnSe. It was made simple, low mass and high image quality by introducing diffraction surface and even aspheric surfaces. The evaluation of the system was given in the temperature range -80-160 ℃. The results show that the modulation transformation function （MTF） is near to 0.6 at the spatial frequency of 12.5 lp/mm which is near to the diffractive limitation. It is compatible with staring focal plane array which has a format of 320×240 and the pixel pitch of 40 μm.
出处
《红外与激光工程》
EI
CSCD
北大核心
2011年第1期79-82,共4页
Infrared and Laser Engineering
基金
国家自然科学基金资助项目(60808028
40301031)
