Digital holography is an increasingly attractive method for optical metrology[1,2]. It enables direct access to re construct both an intensity image and a phase image simultaneously[3] . The phase image can provide quan titative information about the three-dimensional (3D) structure of the specimen, which is one of the signif icant advantages of digital holography. How to acquire a high quality phase image by numerical reconstruction has been a very important research topic. There are various

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