摘要波长移相干涉仪可用于大口径光学元件的测试。在长腔长测试条件下，由于激光器的波长调谐驱动源的精度有限， 采用定步长移相算法求解相位分布的精度不高。在分析干涉腔长和波面计算误差的基础上，提出了一种自适应相位筛选计算方法。根据电压——相位标定曲线采集多组周期干涉图，对干涉图中的光强值进行均匀分布抽样，采集到足够多的干涉图后对其进行随机移相计算，求取每帧干涉图精确的步进移相量，从中筛选出移相量为 的四帧干涉图，利用四步移相计算公式求得精确的相位分布。实验结果表明，在波长移相干涉仪中运用该方法，可以很好地解决长腔长测试条件下的相位计算问题，与未进行筛选的计算结果比较，其测试精度得到了显著提高。 64816

毕业论文关键词：波长移相干涉； 相位筛选；  长干涉腔； 测量

毕业设计说明书（论文）外文摘要

Title   An Adaptive Phase Selecting Method of Wavelength Tuning at Long Interference Cavity Length                                             

Abstract

The wavelength tuning interferometer is applied to measure large optical components. When it is measured at long interference cavity length, the calculating precision of algorithms with certain steps is low. It is mostly because of the limited resolution of the laser controller. Based on analyzing the relationship between the interference cavity length and the calculating error of the wavefront, an adaptive phase selecting method is presented. First, several periods of interferograms are sampled according to the voltage-phase calibration curve. Then the intensity values of the interograms are uniformly sampled. By calculating the sampled intensity values with the randomly phase shifting algorithm, the phase steps between every two interferograms are obtained. According to the steps, four interferograms with   step are chosen from those interferograms. At the end, the measured wavefront is obtained by calculating the four interferograms with four-step phase shifting formula. The experimental result shows the validity of the presented method. It can obtain the wavefront when it is measured at long interference cavity length in the wavelength tuning interferometer. And after comparing with the result of no selection method, it is clear to see that the presented method is of high precision. 

Keywords  measurement; wavelength tuning interferometry; adaptive; phase selecting; long interference cavity length

目  录

1 绪论 1

1.1  课题研究背景 1

1.2  国内外研究现状 2

1.3  主要研究工作 3

2  移相干涉技术 4

2.1  移相干涉技术基本原理 4

2.2  四步法基本原理 4

2.3  本章小结 6

3  长干涉腔下的波长移相干涉算法的研究 7

3.1  干涉腔长与波面误差 7

3.2  随机移相算法基本原理 9

3.3  相位筛选 11

3.4  算法分析 12

3.5  本章小结 13

4  实验结果及分析 14