Shape measurement of microscopic object by using digital lateral shearing holography

Abstract

A phase reconstruction method which is combined digital holography with digital lateral shearing interferometry has been analyzed and verified by computer simulation. The results show that one-dimensional phase unwrapping procedure must be applied to the original reconstructed phase field before lateral shearing. An effective method to eliminate the linear term of the shearogram automatically have been proposed and demonstrated. Moreover, the simulation results also show that the maximum of the difference between two adjacent pixels of the shearogram must be less than 2π in order to reconstruct phase map correctly. If the value is more than 2π, an adoptable method is padding zeros to the recorded hologram appropriately.