Enhanced wavefront reconstruction of diffuser-embedded objects by surface smoothening agents
The quality of an object wavefront gets compromised as it passes through a diffuser, introducing a random phase-shift for each pixel region. To alleviate this problem, a technique based on the application of surface-smoothening agents is presented, forcing the overall phase-shift to approximate a uniform distribution by adding enough material for each pixel region. Employing digital holography, object wavefronts obscured with diffusers of varying depths of randomization are investigated. Influences on the quality of wavefront reconstructions such as refractive index differences of the diffuser and agent as well as the area of spaces between them (air bubbles) are characterized and optimized. The technique provides a strategy for evaluating structures hidden beneath scattering surfaces.