利用波长移相干涉技术对平行平板的前后表面同时进行非接触测量在光学检测领域具有重要意义。阐述一种可实现平行平板前后表面干涉混叠信号解相的时域加权算法：加权36步采样算法。首先基于算法原理与约束条件进行了加权多步采样算法的基础分布参数的设计，进而得到前表面、后表面、厚度变化干涉信号的采样权值。利用该权值进行加权操作即可得到各表面初始相位分布。选用泽尼克多项式进行了多表面干涉解相的仿真，模拟的分离结果与真值的最大误差不超过0.06 nm。此外还分析了多种误差对测量结果的影响。论文对这一厚度为20 mm的平行平板开展了测量，验证了该算法在实际测量过程中的有效性。

The simultaneous non-contact measurement of the front and rear surfaces of parallel plates by using wavelength phase-shifting interference technology was of great significance in the field of optical determination. A time-domain weighting algorithm was proposed to solve the overlapping interference signals of the front and rear surfaces of parallel plates: weighted 36-step sampling algorithm. Firstly, based on the principle and constraints of the algorithm, the basic distribution parameters of the weighted multi-step sampling algorithm were designed, and then the sampling weights of the interference signals of front surface, rear surface and thickness variance were obtained. Through the calculation of the basic distribution parameters, the sampling weight of each surface can be obtained, and the initial phase distribution of each interference information can be obtained by using the weight operation. Based on Zernike polynomials, the simulation of multi-surface interference phase solution was carried out, and the maximum error between the simulation result and the true value was not more than 0.06 nm. In addition, the influence of various errors on the measurement results was analyzed. A parallel plate with a thickness of 20 mm has been measured. The experiment verifies the effectiveness of the algorithm in the actual measurement process.