A CMOS digital pixel sensor with photo-patterned micropolarizer array for real-time focal-plane polarization imaging

Abstract

In this paper, a CMOS digital pixel sensor integrating a novel photo-patterned micropolarizer array is proposed for real-time polarization imaging. The sensor is based on a compact Pulse Frequency Modulation (PFM) spiking pixel, which provides a relative immunity to the continuing scaling of power supply voltage in CMOS technologies. In contrast to previously reported implementations, the proposed micropolarizer array fabrication technology is not only simple but also completely removes the need for complex selective etching. Instead, we propose to use light to pattern micropolarizer elements at the pixel pitch. Reported results in 0.18 mum CMOS technology validate the concept of a compact, low cost, polarization image sensor integrated on a single chip.