两重外腔的自混合干涉及其信号分析

Self-Mixing Interferometry of Dual External Cavities and Its Signal Analysis

提出了具有两重外腔的自混合干涉。根据半导体激光器的自混合干涉理论 ,研究了两重外腔自混合干涉模型 ,及其信号的调制和解调方法。该方法用一个附加的参考反射镜在半导体激光器 (LD)和目标间形成两重外腔 ,参考外腔用于补偿光学频率涨落引入的相位误差。用快速傅立叶变换相位探测技术 (FFT)分析自混合干涉信号。运用这些方法 ,可提高相位测量精度 ,在微光机电系统、光学工程和其他工程应用上有潜在的实用价值。

A novel self-mixing interferometry (SMI) with dual external cavities was proposed. The model of interference, as well as the modulation and demodulation of interference signal are analyzed. The developed technique uses an additional reference reflector to form dual external cavities between the LD and the target, and reference external cavity is used to compensate the phase error due to optical frequency fluctuation. FFT phase detection technique was applied to analyze SMI signal. By using these techniques, the high precision measurement results can be obtained. It is a promising technique used in microelectromechanical systems (MEMS), optical engineering and other engineering application.