Single‐Shot Reference‐Free Holographic Imaging using a Liquid Crystal Geometric Phase Diffuser

Abstract

Abstract It has been recently demonstrated that wavefront information can be directly measured using the speckle‐correlation scattering method. The realization of speckle‐correlation scattering requires the use of a diffusive layer; however, it poses technical challenges in characterizing the transmission matrix of the diffusive layer or precisely fabricating an engineered random metasurface. Herein, liquid crystal geometric phase diffusers are exploited for single‐shot reference‐free holographic imaging based on speckle‐correlation scattering. It is demonstrated that the use of a commercial geometric phase diffuser provides precise holographic measurements in a simple imaging setup, with no calibration required. This low‐cost, simple, and high‐resolution wavefront sensing approach inspired by liquid crystal materials may find direct applications in metrology, industrial inspection, and biophotonics.