随着现代战争中伪装技术的日益增强，瞄准镜的性能对**威力的发挥起到至关重要的作用。结合红外与变倍特性的瞄准镜系统将在观测中发挥重要的作用。本文设计的双视场红外瞄准镜系统工作波段为 8～11 μm，视场大小变化范围为 0.716°/2.886°，实现了 4倍的变倍比。同时，由于红外材料对温度变化敏感的特性，对光学系统进行了被动消热差设计，保证了系统在－40℃～60℃工作温度内成像质量稳定。系统采用德国 AIM公司的长波非制冷探测器接收红外信号，为了实现可加工性，所有面型皆为球面。通过对透镜形式的合理选择，透镜之间的合理搭配，最终实现光学系统的设计，系统成像质量良好，环境适应性强。

With the improvement of the modern camouflage technology, it requires more and more high performance of the aiming system. Variable magnification（zoom）rate aiming system can be more flexible than the fixed rate one in practical use. Infrared optical system can obtain infrared information on the objects. The optical system combined of these two characters will play an important role in the detection. The working band of the system is 8～11 μm, field of view is 1.13°/4.52°. Meanwhile, the system can be athermalized during the working temperature －40℃～60℃ by adopting passive athermalize design method. Detector made by Germany’s AIM was used to receive infrared signals. All surfaces are spherical to make manufacture more easier. Optical system has a good image quality, and high environmental adaptability.