反远距成像相移剪切散斑干涉检测系统

摘要

A retro-focus Michelson type shearing speckle interferometry imaging system was proposed to extend the field of view (FOV)for a speckle shearing interferometer.The retro-focus imaging system includes negative lens group and television lens.Analysis of the optical setup was taken out and the simulation was demonstrated by ZEMAX software.The phase shifting unit was a plane mirror attached with a piezo,the non-uniform phase difference caused by the tilted mirror was discussed.The equal-step Carre algorithm was used to calculate the phase map so that the non-uniform phase error was avoided.The experiment results of center loaded metal plane show this method can achieve large FOV detection system.A 70°FOV imaging system can be implemented by using three plano-concave lenses with -75mm focus length and the FOV can be adjusted by changing the focus length and number of lenses.%为了扩大传统剪切散斑干涉仪的检测视场，设计了一种反远距成像迈克尔逊式剪切散斑干涉系统。采用负透镜组与标准成像镜头组成反远距成像系统，分析了光路的成像参量，并利用 ZEMAX 软件进行了模拟；讨论了发散光路时间相移的非均匀性，采用等步长相移算法进行相位解算可以弥补非均匀误差；并对中心加载的橡胶平板进行了测量。结果表明，该系统能有效地扩大成像视场，采用3片焦距为-75mm 的平凹镜片可以实现70°视场角的散斑干涉检测，通过调整平凹镜片的焦距和数量可以实时调整成像视场。