8-12μm波段折／衍混合红外连续变焦光学系统

Diffractive/Refractive Infrared Continuous Zoom System in 8～12 μm

针对长波160×120元非制冷焦平面阵列探测器,设计了8～12μm波段折/衍混合红外连续变焦光学系统。该系统采用机械补偿的变焦方式,变焦过程中相对孔径不变,F数为1.0,系统变焦比为4:1,在一定焦距范围内可实现连续变焦。变焦系统仅采用锗材料,通过引入衍射面和高次非球面校正系统色差和轴外像差,在空间频率14lp/mm处,全焦距范围内MTF均在0.7以上,成像质量较好,可以连续变焦,并给出了变倍组和补偿组的变焦运动曲线。

For long wavelength uncooled staring focal plane array（UFPA） detector, an infrared diffractive/refractive continuous zoom system in 8- 12μm was presented. The zoom system was mechanical compensation LWIR, the relative aperture was invariant during the zoom process. The F number of the system was 1.0,and the zoom ratio was 4：1. The focal length of the system can be changed continuously. The system had only germanium materical, the binary surface and high order aspheric surface were used to proofread lateral color, longitudinal color and off-axis aberration. When spatial frequency was 14 lp/mm, MTF in the whole focal exceeded 0.7, the system had high image quality, and showed the zoom movement curve of zoom group and compensating group.