Integrated polarization-analyzing CMOS image sensor

A CMOS image sensor with an integrated wire grid polarizer to sense the polarization of light is presented. The chip consists of an array of 128 by 128 pixels, it occupies an area of 5×4 mm
²
and it has been designed and fabricated in a CMOS 180nm process. Extinction ratio of 6.3 and 7.7 were achieved. The sensor is used to classify materials based on the degree of polarization and the transmitted intensity after specular reflection on the material surface. The variation in the transmitted intensity among dielectrics and metals was successfully demonstrated.