用于位移精密测量的光外差马赫-泽德干涉仪

Mach Zehnder heterodyne interferometer for high precision displacement measurement

本文介绍了我们研制的用于位移精密测量的光外差马赫－泽德干涉仪。由于在光路设计中采用了共光路的布置，共模抑制技术得以实现，环境干扰产生的噪声得到很好的消除，相位检测的稳定性和精度大大提高。使用该干涉仪测量了一台在光学相移器内ＰＺＴ微位移驱动装置的电压－位移关系。测量结果具有良好的线性和重复性，与预期相符。根据测量数据分析，该光外差干涉仪具有３ｎｍ的位移测量精度。

A Mach Zehnder Heterodyne Interferometer for high precision displacement measurement is developed and demonstrated. By using the common path optical arrangement,the optical common mode rejection technique has been realized. Noises caused by environmental disturbance are eliminated dramatically. Good stability and accuracy of the phase detection have been obtained. The Interferometer is used to study the relationship between voltage and displacement for a PZT microactuator in an optical phase shifter. The results agree with predictions, showing good linearity and repeatability. The experimental results show that the optical heterodyne interferometer has the accuracy of 3mm for displacement measurement.