基于偏振合束的相移雅满剪切干涉仪

Phase Shifting Jamin Shearing Interferometer Based on Polarization Combination

相移雅满横向剪切干涉仪非常适合于达到衍射极限的光束的波面检测。为了改进现有的在两路剪切光束中直接插入起偏器的相移雅满剪切干涉仪,提出了一种基于偏振合束的相移雅满剪切干涉仪。该剪切干涉仪利用雅满平板前后表面的反射进行分束并形成两路干涉光束,两路干涉光束分别通过剪切平板后偏振合束并进行偏振移相。它保持了常规雅满剪切干涉仪的光路结构,提高了剪切干涉图的对比度,不再存在插入起偏器引入测量误差的问题。构建了改进前、后的两种相移雅满双剪切干涉仪,并进行了相应的对比实验,实验结果很好地验证了基于偏振合束的相移雅满剪切干涉仪的实用性。

The phase-shifting Jamin shearing interferometer is very fit for measurement of diffraction-limited wavefront.To improve the performance of existing phase-shifting Jamin shearing interferometers with two polarizers,a phase-shifting Jamin shearing interferometer based on polarization combination is proposed.In the interferometer,the beam to be measured is reflected by two surfaces of the Jamin plate to form two interfering beams.They are polarized and combined to form a polarization phase-shifting interferogram.The interferometer keeps up the optical configuration and improves fringe visibility.Two kinds of phase-shifting Jamin doube-shearing interferometers before and after improvement are built for experiments.Results show that the usefulness of the interferometer is verified.