A novel hybrid polarization-quadrature pixel cluster for local light angle and intensity detection

Abstract

Detecting local light incident angle is a desirable feature for CMOS image sensors for 3D image reconstruction purposes. Advances in the CMOS technologies in the last years have enabled integrated solutions to perform such a job. However, it is still not viable to implement such a feature in regular CMOS image sensors due to the great number of pixels in a cluster to perform incident angle detection. In this paper, a hybrid cluster with only four pixels, instead of eight pixels of previous solutions, that is able to detect both local light intensity and incident angle. The technique to detect local incident angle is widely exploited in the literature. Two novelties are explored in this work, the first is the new paradigm in polarization cluster-pixel design and the second is the extended ability of metal shielded pixels to detect both the local light angle and intensity. SPICE simulation results show that the existing Quadrature Pixel Cluster - QPC and Polarization Pixel Cluster - PPC models are in accordance with experimental results presented in the literature, and thus it was possible to demonstrate similar behavior in the new proposed pixel cluster.