CMOS ACTIVE PIXEL SENSOR FOR A POLARIZATION- DIFFERENCE CAMERA NSF Summer Undergraduate Fellowship in Sensor Technologies

Polarization-sensitive vision is well documented as serving in navigation for many animals, but some types of biological polarization-sensitive vision may enhance object visibility in scattering media. Because neither the human eye nor conventional cameras are polarization-sensitive, artificial polarization vision systems must be designed to exploit the polarization of light; artificial polarization-difference imaging has been shown to be capable of enhancing target detection in scattering media. Previous polarizationsensitive cameras required external processing, were not real-time, and used relatively large amounts of power. A CMOS active pixel sensor is presented for use in a low power, portable, real-time polarization-difference camera. Pixels were designed for integration with a diffractive optical element polarization analyzer. Column readout circuits include fixed pattern noise suppression. In addition, a scaling methodology to enhance system performance and to correct for non-ideal polarization analyzers is presented. 1