锁相放大器在激光外差信号检测中的应用

目前，激光外差技术在激光测振、测速和测距等精密测量中已有广泛的应用，但在这些应用中待检测的光信号都非常微弱且含有大量噪声。为了提取该信号采用锁相放大器作为系统检测电路，在分析锁相放大器原理的基础上，设计了锁相放大器各模块电路并仿真。经实验测试，在给锁相放大器加幅度为0．01～0．5mV的信号时，在电路输出端可以得到信号。

Use of the Lock-in Amplifier Laser Heterodyne Signal Detection

At present, the laser heterodyne technology has been widely used in precision meas- urement of the laser vibrometer, velocity, ranging in these applications to be detected optical signal is very weak and contains a lot of noise in order to extract the signal using the lock- in amplifier as a detection circuit. On the basis of the principle of a- nalysis of lock - in amplifier, the design of lock - in amplifier circuit and the simulation of each mod- ule. Experimental test, the lock - in amplifier to in- crease the range of 0.01-0.5 mV signal,the cir- cuit output can be obtained signal.