Due to its low complexity and acceptable accuracy, phase retrieval technique has been proposed as an alternative to solve the classic\noptical surface measurement task. However, to capture the overall wave field, phase retrieval based optical surface measurement\n(PROSM) system has to moderate the CCD position during the multiple-sampling procedure. The mechanical modules of CCD\nmovement may bring about unexpectable deviation to the final results. To overcome this drawback, we propose a new PROSM\nmethod based on spatial light modulator (SLM). The mechanical CCD movement can be replaced by an electrical moderation of\nSLM patterns; thus the deviation can be significantly suppressed in the new PROSM method. In addition, to further improve the\nperformance, we propose a new iterative threshold phase retrieval algorithm with sparsity-constraint to effectively reconstruct the\nphase of wave field. Experimental results show that the new method provides a more simple and robust solution for the optical\nsurface measurement than the traditional techniques and achieves higher accuracy.
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