High Dynamic Range Backside Illuminated Voltage Mode Global Shutter CIS for in Cabin Monitoring
Although global shutter operation is required to minimize motion artifacts in in-cabin monitoring, it forces large changes in the CIS architecture. Most global shutter CMOS image sensors available in the market today have larger pixels and lower dynamic range than rolling shutter image sensors. This adversely impacts their size/cost and performance under different lighting conditions. In this paper we describe the architecture and operation of backside illuminated voltage mode global shutter pixels. We also describe how the dynamic range of these pixels can be extended using either multiple integration times or LOFIC techniques. In addition, how backside illuminated voltage mode global shutter pixels can be scaled, enabling smaller more cost effective camera solutions and results from recent backside illuminated voltage mode global shutter CIS will be presented.