Quantitative measurement for the structure of defects on optical surface with lensless Fourier transform digital holographic microscopy

An effective method for detecting the structure of defects on optical surface is proposed. By integrating the lensless Fourier transform holography with digital holographic microscopy, the wave aberration induced by the defects is effectively recorded and then the accurate reconstruction result of the defect structure is obtained by using the phase subtraction method. This method will have potential application in the quantitative measurement for the defects on optical surface and is helpful for the further research and understanding the influence of surface defects on high-power laser system.