声光延迟效应用于消除微弱背景光噪声

摘要

A method for eliminating the weak optical background is presented in the pulse laser transmitting using the acousto-optical delay effect. The background photons with the same optical fiequency of the pulsed laser can be suppressed effectively by using two tandem acousto-optic modulators working as optical switches. The signal to noise improvement ratio is up to 13 dB. Here, the first acousto-optic modulator is used to separate the pulse signal and the background photons in time domain. The second one is used to notch the separate background photons. This method could be applied in the range of precision measurement and information processing for pulse light sensitive detection.%本文提出一种基于声光延迟效应消除脉冲光信号中微弱背景光噪声的方法,利用两个串联的声光调制器组成的光学开关有效地抑制了与信号光同频率的背景光,信号背景改善比达13 dB.其中,第一个声光调制器的作用是利用其对脉冲光的非线性光学延迟效应实现信号光与背景光在时序上的分离.第二个声光调制器将时域上已经和脉冲信号光分开的背景光消除.这种方法适用于精密测量和信息处理等领域的脉冲光信号的高灵敏检测.