本文介绍了激光半主动制导**目标模拟系统中宽范围、高精度、无级激光能量衰减单元。它由大小两个棱镜、精密位移平台、控制器、光栅尺组成。其激光能量调节原理基于朗伯定律，只需改变光束穿过物质厚度，即可改变光强。系统实现激光能量的宽范围、高精度、高动态连续无级调节，与传统的激光能量大小调节系统相比较，它解决了能量变化动态范围小、线性度不好、需要多级级联等问题，同时具有结构简单、稳定性高、加工成本低等优点。使用1 064 nm 激光器进行了实验与测试，并给出了设计方案及其实现过程，对激光能量大小调节的研究起到了推动作用。

This article describes the attenuation unit of laser energy of wide range, high precision and stepless in the semi-active laser guided weapon simulation system, which consists of two prisms (different sizes), precision displacement platform，controller and grating. The optical energy regulation principle is based on Lambert law. Only by changing the material thickness which the beam passes through，the light intensity could be changed. It achieves a wide range, high accuracy, high dynamic, continuous and stepless adjustment of laser energy. Compared with the traditional laser energy regulation system, it solves these problems such as the energy dynamics of small range, unsatisfied linearity, needing to multi-stage cascade and so on, and also has a simple structure, high stability, and low processing costs. We take 1064nm laser as the experiment, gives the design scheme and its implementation process. The method plays a role in promoting this technology.