Liquid crystal on silicon-based real time phase stepping interferometry by spatial multiplexing

In this paper, we present a method to perform phase-shifting interferometry in real time. The technique is based on the use of a parallel aligned liquid crystal on a silicon display as a customized reference mirror. In order to imple-ment the four-step algorithm, a set of macropixels is programmed onto the display, and these are divided into four zones with the appropriate phase shifts. This way, by spatial multiplexing, it is possible to obtain the phase of the wavefront at a rate limited only by the integration time of the employed detector. The customized mirror is able to both compensate the initial curvature of the object under study and introduce the necessary phase shifts to perform phase calculation. Examples of the phase reconstruction of static and dynamic objects are shown. (c) 2023 Optica Publishing Group

Automated summary

In this paper, a real-time phase-shifting interferometry method is presented. The method utilizes a parallel aligned liquid crystal on a silicon display as a customized reference mirror. By programming macropixels into the display and dividing them into four zones with appropriate phase shifts, the phase of the wavefront can be obtained at a rate limited only by the integration time of the detector. The customized mirror compensates for the initial curvature of the object and introduces the necessary phase shifts for phase calculation. Examples of phase reconstruction for static and dynamic objects are demonstrated.