基于外差干涉的激光超声检测技术  

Laser Ultrasonic Displacement Detection Technology Based on Heterodyne Interference

作　　者：司高潞 张志伟[1,2,3] 

机构地区：[1]中北大学信息与通信工程学院,太原030051 [2]中北大学电子测试技术重点实验室,太原030051 [3]中北大学仪器科学与动态测试教育部重点实验室,太原030051

出　　处：《电子器件》2016年第1期124-127,共4页Chinese Journal of Electron Devices

基　　金：山西省自然科学基金项目(2012011010-1)

摘　　要：激光超声的震动位移是在纳米级别,所以要检测到微弱的激光超声需要外差干涉系统有较高的灵敏度。为了提高测量精度对光路进行了改进,采用双光路外差干涉仪增强系统抗环境干扰能力,使用3聚焦透镜增强干涉仪的聚光能力,提高进入干涉仪的光通量,从而提高精度;在光电探测器前加滤光片,滤除杂散光,提高系统信噪比。通过高频超声实验验证,该系统的位移分辨率能达到0.1 nm。Laser ultrasonic vibration displacement is in the nanometer level. In order to detect weak signal of laser ultrasonic,heterodyne interferometer system requires higher sensitivity. In order to improve the measurement preci-sion,the optical path has been improved. The double light path heterodyne interferometer enhances anti-interference capability of system,the lens are used to enhance the light gathering power of the interferometer,Increasing the flux of interferometer,so it can improve the precision of measurement. The filter is installed in front of photoelec-tric detector,filter thestray light and improve the system signal-to-noise ratio. By high-frequency ultrasonic experi-mental verification,the displacement resolution of the system can reach 0.1 nm.

关 键 词：纳米位移 外差干涉 激光超声 聚焦 

分 类 号：TN247[电子电信—物理电子学]