激光四象限探测系统是激光制导**的重要组成部分，在设计阶段对其性能的准确评估有利于设计方案的迭代和优化。采用LitghtTools软件对四象限探测系统进行了仿真建模。通过建立目标模型、光学系统模型和四象限探测器模型，可以有效地对系统进行仿真，并结合四象限探测系统原理，得到角度偏差的和差比幅值；建立的模型可以对系统的杂散光进行仿真，评估杂散光对系统的影响；另外，还可以模拟激光散斑效应，分析散斑特性对探测系统输出和差比幅值的影响，通过LitghtTools软件建模和仿真为设计优化提供了准确的依据。最后，通过实验对仿真模型进行验证，在±15°范围内仿真得到的和差比幅值和实验结果基本一致。

The laser four-quadrant detection system is an important part of laser guided weapons. The accurate evaluation of its performance in the design stage is conducive to the iteration and optimization of the design scheme. The simulation model of the four-quadrant detection system was established based on LitghtTools. Through the establishment of target model, optical system model and four-quadrant detector model, the system could be effectively simulated. Combined with principle of four-quadrant detection system, the sum-difference amplitude of angle deviation could be obtained; the stray light of the system could also be simulated to evaluate the impact of stray light on system; in addition, it could also simulate the laser speckle effect and analyze the influence of speckle characteristics on the sum-difference amplitude. Therefore, the modeling and simulation based on LitghtTools provided an accurate basis for design optimization. Finally, the simulation model was verified by experiments. The sum-difference amplitude of the simulation is basically the same as that of the experiment in the range of ± 15°.