A Color Image Sensor Using $1.0-\mu \mathrm{m}$ Organic Photoconductive Film Pixels Stacked on $4.0-\mu \mathrm{m}$ Si Pixels for Near-Infrared Time-of-Flight Depth Sensing

We have developed an image sensor capable of obtaining RGB images and ranging information on a single chip by layering $1.0-\mu \mathrm{m}$ organic photoconductive film RGB pixels that absorb visible light on $4.0-\mu \mathrm{m}$ indirect-time-of-flight $(\text{iToF})$ silicon pixels that utilize near-infrared (NIR) light. The spectral design of the organic photoconductive film and the arrangement of the RGB cut filter between the RGB pixel and the ranging pixel suppress NIR color mixing into the RGB pixel and RGB color mixing into the NIR pixel. Using this sensor, it is possible to simultaneously acquire high-resolution RGB images with good color reproduction and parallax-free ranging information even under conditions where both visible and NIR light are present.