基于正弦光栅的凝视型激光探测告警系统的设计与实现

当激光入射到正弦光栅时,会产生0级和±1级衍射谱线,通过测量衍射谱线的分布,可获得入射激光的波长及方位角信息。为了实时探测激光光源的波长和方位角,设计了一种基于正弦光栅的凝视型激光探测告警系统。介绍了系统的工作原理,推导了激光波长和方位角的计算公式,并对系统的探测精度进行了数值模拟研究。分析了光栅常数和柱面镜曲率半径对系统探测能力的影响,并且给出了相关函数。实验结果表明:当光栅常数为1/500mm、柱面镜曲率半径为20mm时,系统可实现对波长为320～1100nm、视场角为±20°范围内激光源的实时探测,波长分辨率可达到10nm,角分辨率可达到1°。

Design and Realization of Staring Laser Detecting and Warning System Based on Sinusoidal Grating

Incident laser passing through sinusoidal grating diffracts as zero-order and plus or minus one-order spectra. The wavelength and direction of incident laser can be measured by reading the position of the spectrum from the detector. In order to detect the wavelength and direction of laser light, a staring laser detecting and warning system based on sinusoidal grating is designed. Working principle of the system is introduced, computing formulas of wavelength and azimuth of the incident laser are deduced, and detecting accuracy is studied by numerical simulation. Influence of grating constant and cylindrical lens radius on detectivity of the system is studied and the related function is provided. Experimental results show that the laser detecting and warning system can realize real time measurement of laser with the wavelength range of 320~1100 nm, field of view of ±20° when the grating constant is 1/500 nm and the cylindrical lens radius is 20 mm, where the wavelength resolution is less than 10 nm and the angular resolution is less than 1°.