A UHDTV Camera System With Multiplane Phase-Detection Autofocus

Abstract

We propose a phase detection autofocus (PDAF) method for three-chip 8K (UHD-2) 240-frame/sec cameras that detects the in-focus position of a lens by using disparity information between pixels with different apertures across multiple sensors. This multiplane PDAF method executes pupil division in the same incident position while using simple metal-shielded pixel technology, which can achieve accurate AF and enable low-cost implementation. The proposed method implemented in a UHD-2 three-chip camera incorporating UHD-2 sensors with half-shielded phase-detection pixels into the blue and red channels demonstrated more robust disparity calculation than the conventional single-chip metal-shielded-based PDAF method.