We present a method based on polarization spatial phase-shifting interferometry for evaluating the surface quality of concave axicons with high reflectivity, which is achieved by double reflections of the axicon. In this method, a transmitted test beam of a phase-shifting interferometer is reflected by the reflective axicon, the transmission flat (TF) and the reflective axicon consecutively. The test beam is perpendicularly incident on the TF by the second reflection of the axicon. Then, the surface quality of the axicon can be obtained by the interference of the test beam and the reference beam in the interferometer. The surface quality of the reflective axicons with different cone angles and diameters can be rapidly evaluated in this simple measurement configuration. Experimental results are presented for the metrology of an approximately 164° cone angle sample, which agree well with the results of the profilometer.

中文翻译：

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用于评价高反射率凹面轴锥的表面质量的评价方法

我们提出了一种基于偏振空间相移干涉术的方法来评估具有高反射率的凹轴锥的表面质量，这是通过轴锥双反射实现的。在这种方法中，相移干涉仪的透射测试光束被反射轴锥，透射平面（TF）和反射轴锥连续反射。测试光束通过轴锥的第二次反射垂直入射到TF上。然后，可以通过干涉仪中测试光束和参考光束的干涉来获得轴锥的表面质量。在这种简单的测量配置中，可以快速评估具有不同锥角和直径的反射轴的表面质量。