High Contrast Ultrathin Light-Field Camera Using Inverted Microlens Arrays with Metal-Insulator-Metal Optical Absorber

Abstract

Light-field imaging has attracted much attention in constructing 3D objects with a simple configuration and capturing all the spatial and directional data in a single photographic exposure. Here, an ultrathin light-field camera (ULFC) for high contrast and high-resolution light-field imaging using a metal-insulator-metal optical absorber based inverted microlens arrays (MIM-iMLA) is reported. A metal-insulator-metal based optical absorber (MIM-OA) between microlenses exhibits high light absorption in the full visible region, thereby highly blocking microlens crosstalk. The MIM-iMLA double the image contrast and improve MTF50 by up to 32%, compared to conventional light-field image. In addition, the MIM-iMLA substantially reduces an image plane distance and brings the objective lens position closer to the MLA. The ULFC exhibits a short total track length of 5.1 mm, demonstrating high contrast light-field image acquisition and high accuracy 3D depth map estimation after light-field rendering. This ultrathin and high contrast light-field camera can provide a new platform for miniaturized 3D cameras in biomedical applications, biometrics, automated inspection, or mobile camera applications.