激光反射式光幕探测技术研究

Light curtain sensor based on laser reflection

针对现有天幕靶探测灵敏度低、易受天空亮度影响、夜间不能工作等问题,提出了一种基于激光反射的主动式光幕探测方案,该方案采用一字线结构光半导体激光器作为主动光源,采用光学镜头、狭缝光阑、滤光片和光电倍增管组成光路探测系统。当飞行弹丸穿越一字线结构光半导体激光器和光路探测系统共同组成的探测光幕时,弹体表面反射回的部分光线被光路探测系统接收,经光电探测器件光电转换,并经后续信号处理电路对光电探测器件产生的电信号进行处理,输出与飞行弹丸穿越探测光幕面时刻相对应的模拟信号和脉冲信号。对系统光能量进行分析和计算,并通过实弹试验测试,结果表明:系统能够在夜间正常使用,灵敏度达到200倍以上弹径。

For the problems of low detection sensitivity, susceptibility to sky brightness and ina- bility to work at night of existing sky screens, a detecting method was put forward which was an active light curtain based on laser reflection. A line laser semiconductor was adopted as the active light source in the design, and the light path detection system consisted of optical lens, slit diaphragm, optical filter and photomnltiplier tube. When the flying projectile passed through the light curtain composed of the line laser semiconductor and the optoelectronic detec- tion system, part of the light reflected from the surface of projectile body were received by the optoelectronic detection system. After the process of photovoltaic conversion by photovoltaic detectors and the processing of electrical signal generated by photovoltaic detectors using the subsequent signal processing circuit, the corresponding analog signal and pulse signal indica- ting the moment when the flying projectile passed through the light curtain were output. Light energy was analyzed and calculated, and finally tested by experiment. The results show that the method can be used at night and the sensitivity is up to more than 200 times of the projec-tile diameter.