建立了一套基于马赫-曾德尔干涉仪的测量系统,获得了透射式相位光栅的相位信息并推算出光栅的表面形貌。给出了相位测量法的基本原理,运用傅里叶变换法和相位解包裹技术,对实验系统采集的干涉图的相位信息进行处理并计算出光栅的高度、周期和底角等结构参数。结果表明,该测量方法和系统能够精确地测量光学相位元件的表面形貌,具有较高的实用价值。 A measuring system based on Mach-Zehnder interferometer was established. The phase information of transmission phase grating was obtained and the surface morphology of grating was deduced. The basic principle of phase measurement is given. The Fourier transform and phase unwrapping techniques are used to process the phase information of the interferogram collected by the experimental system and to calculate the structural parameters such as height, period and bottom angle of the grating. The results show that the measurement method and system can accurately measure the surface morphology of the optical phase component and have high practical value.