正弦相位调制的固体激光自混合干涉振动测量  

Sinusoidal phase-modulation solid-state laser self-mixing interference vibration measurement

作　　者：王汉睦 王琦 聂晓明 罗晖[1] 周健[1] WANG Hanmu;WANG Qi;NIE Xiaoming;LUO Hui;ZHOU Jian(College of Advanced Interdisciplinary Studies,National University of Defense Technology,Changsha 410o73,China)

机构地区：[1]国防科技大学前沿交叉学科学院,湖南长沙410073

出　　处：《光学技术》2024年第3期333-338,共6页Optical Technique

基　　金：中国博士后科学基金面上资助(2022M713879);湖南省自然科学基金(2021JJ30782);国防科技大学自主研究项目(ZDJC19-12)。

摘　　要：基于正弦相位调制的激光自混合干涉技术,实现了扬声器表面、白纸等粗糙表面微小振动的精密测量。选用532nm固体激光器作为激光光源,基于电光调制器实现激光的正弦相位调制,相应的调制频率为251kHz。通过混频器/滤波器电路,从正弦相位调制的自混合干涉光学条纹中分别提取由位移变化导致的高信噪比正弦和余弦函数激光功率振荡信号,并进一步获得由于位移变化导致的激光相位变化。因此,可以从激光的相位变化中高效率计算出外部目标的振动与位移。通过与一精度为50nm的精密位移平台进行对比测量,两种仪器的测量结果吻合良好,实验验证了本文中激光自混合干涉仪的性能。文章的新技术可以为高精度低频微振动、微位移测量提供可靠的技术支持。Based on the sinusoidal phase-modulation laser self-mixing interference technique,the precision measurement of the small vibration on the rough surface is realized,such as speaker surface or white paper.The 532nm solidstate laser is selected as the laser light source.And the sinusoidal phase-modulation of the laser is achieved based on the electro-optical modulator,with a corresponding modulation frequency of 251kHz.By using the mixer/filter circuits,the high signal-to-noise ratio sinusoidal and cosine function laser power oscillation signals caused by displacement change are extracted from the self-mixing interference optical fringes modulated by sinusoidal phase-modulation,further obtaining the phase change of the laser caused by displacement change.Therefore,the vibration and displacement of external targets can be efficiently calculated from the phase change of the laser.By comparing the measurement results with a precision displacement platform with an accuracy of 5onm,the two instruments showed good agreement,and the performance of the laser self-mixing interferometer was experimentally verified.The new technology can provide reliable technical support for high-precision low-frequency micro-vibration and micro-displacement measurement.

关 键 词：自混合干涉 相位调制 精密测量 振动 

分 类 号：O436.1[机械工程—光学工程] O439[理学—光学]