针对目前半实物仿真采用一弹一仿的问题，提出采用变焦距投影系统的五轴转台仿真方案，使得不同视场、不同焦距、不同型号的导引头可以采用同一套仿真系统进行仿真测试，提高了仿真系统的效费比。分析了红外半实物仿真用变焦光学系统的特点，设计了（8～12）m波段衍射受限红外变焦光学系统，系统入瞳直径80mm，变倍比为3.0，弥散斑直径小于50m。

Since the hardware-in-the-loop (HWIL) simulation systems are designed only for one seeker to one simulator, a five-axis turntable simulation scheme with a zoom projection optical system is proposed. The HWIL simulation systems can be applied to the seekers which have different optical parameters, so it is more cost effective. The characteristics of the zoom projection optical lenses in HWIL simulation system are outlined. The infrared zoom system whose diffraction is limited in the wavelength range of 8m～12m is designed. The zoom ratio of the system is 3.0, and the diameter of spot dispersion is less than 50m.