Imaging phase objects through diffusers based on lensless digital holography

Imaging of phase objects behind scattering media is a challenging task. Intensity imaging through diffusers can be achieved based on digital holography by obtaining the complex amplitude of the diffuser in advance. As described in this paper, we experimentally demonstrate the reconstructed images of phase objects behind diffusers with different diffusion angles by digital holography. Using the complex amplitude information of the diffuser to correct the complex amplitude information of the object through the diffuser, the phase distribution of the object is obtainable behind the diffuser. Imaging of phase objects behind diffusers has been verified through experiments using a plano-convex lens and a wedge substrate as phase objects with various scattering angles. Quantitative analyses of the phase objects are performed. The lens shape can be visualized from the known refractive index. Moreover, the curvature radius can be estimated.