Computational Wavefront Sensing on a Photonic Integrated Chip

Abstract

Point‐of‐care diagnostics, in situ monitoring during nanomanufacturing, and in‐line metrology are stimulating demands for portable, ultracompact, and robust optical imaging and metrology systems. In this paper, an on‐chip computational wavefront sensor (OCWS) is proposed and demonstrated by fusing photonic integrated circuits and single‐layer metasurfaces. By simultaneously measuring the optical intensities coupled into the metagratings, OCWS enables the single‐shot acquisition of two orthogonal phase gradient images, from which the wavefront can be computationally reconstructed. Moreover, phase imaging of vortex beams and Gaussian phases is experimentally performed using the OCWS system. This miniaturized system may catalyze diverse applications such as point‐of‐care diagnostics, endoscopy, in situ QPI, and in‐line surface profile measurement.