Characterizing static aberration in reflective liquid crystal spatial light modulators (LC-SLM) using random phase shifting interferometry

To accurate modulate the phase of the incoming light, the backplane aberration of a spatial light modulator (SLM) needs to be measured and compensated. In this paper, we develop an interferometric method to calibrate the static aberration. In our method, a Michelson interferometer was constructed and the SLM itself was used to produce the random phase shift that we need. In addition, the phase demodulation method based on matrix VU factorization (VU) and phase unwrapping algorithm based on derivative Zernike polynomial fitting (DZPT) are adopted to get the phase profile of the static aberration. Experimental result shows that our proposed method can get a pretty good compensation result.