多普勒振镜正弦调制多光束激光外差测量玻璃厚度的方法  

Multi-beam laser heterodyne measurement with ultra-precision for the glass thickness based on oscillating mirror sinusoidal modulation

作　　者：李彦超[1] 王春晖[1] 高龙[1] 丛海芳[1] 曲杨[1] 

机构地区：[1]哈尔滨工业大学光电子技术研究所,可调谐激光技术国家级重点实验室,哈尔滨150080

出　　处：《物理学报》2012年第4期238-243,共6页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:61078063);哈尔滨工业大学重大国际科技合作培育计划(批准号:HIT.ICRST2010024)资助的课题~~

摘　　要：本文提出了一种多普勒振镜正弦调制多光束激光外差测量玻璃厚度的新方法.基于激光外差技术和多普勒效应,通过做简谐振动的多普勒振镜对不同时刻入射光的频率进行正弦调制,把待测厚度信息加载到外差信号的频率差中,通过快速傅里叶变换对外差信号解调后可以同时得到多个待测玻璃厚度值,经加权平均处理可以提高待测厚度的测量精度.利用这种新方法,通过MATLAB仿真测量了不同玻璃厚度值,结果表明:该测量结果的最大相对误差小于0.008%.In this paper,We propose a novel method of measuring glass thickness by means of multi-beam laser heterodyne.Based on the Doppler effect and the heterodyne technology,loading the information about the glass thickness into the frequency difference of the multi-beam laser heterodyne signals by sinusoidal frequency modulation of the oscillating mirror that is in a simple harmonic motion,we can simultaneously obtain many values of the glass thickness through the multi-beam laser heterodyne signal demodulation. Processing these values by weighted-average,the glass thickness can be obtained accurately.This novel method is used to simulate the measurements for different glass thicknesses by MATLAB,the obtained result shows that the relative measurement error obtained by using this method is just 0.008%.

关 键 词：多光束激光外差 多普勒效应 傅里叶分析 非接触式测量 

分 类 号：TN249[电子电信—物理电子学]