实时、可靠地探测敌方来袭激光的类型和特征参数是激光告警的主要任务。相干探测技术依靠激光的相干性探测其信息,是较有效的探测技术之一。为了探测来袭激光光谱信息,设计了一种激光探测与光谱实时测量装置。该装置以相干探测技术和傅里叶光学与光信号处理为基础,使用实心小型静态马赫-泽德干涉具作为相干探测元件,它能有效地抑制背景光,无机械扫描部件,光谱检测速度快,可探测纳秒级窄脉冲激光信号;用高速DSP芯片和多通道帧减技术进行实时信息处理,实现背景噪声去除、激光探测和光谱测量。测试结果表明,运用马赫-泽德干涉具和多通道帧减技术,能实现脉冲激光探测,提高测量精度;可探测激光脉冲宽度为10 ns,波长测量误差小于10 nm。

It is the key content of laser warning to reliably and real-time detect the type and characteristic parameters of incident laser.Coherent detection technology detects the information based on the coherence of laser,and is a kind of effective detection technology.In order to detect the incident laser’s spectrum,a kind of device for laser detecting and real time spectrum measurement was designed,which measures the laser spectrum on the bases of coherent detecting technology,Fourier optics and optical signal processing.Using compact and static Mach-Zehnder interferometer as the coherent detection components,it can restrain the background light efficiently.The non-scanning mechanical parts allow fast spectrum detection,and narrow laser pulse can be detected.The real-time signal processing is realized by DSP and multi-channel frame subtraction technology to wipe off the background light,detect the laser and measure its spectrum.The result indicates that,using Mach-Zehnder interferometer and multi-channel frame subtraction technology can realize the laser pulse detection,and improve the measuring precision efficiently;10 ns laser pulse can be detected and the wavelength measuring error is less than 10 nm.