WORKSHOP PAPER
Pixelated On-Chip Amorphous Silicon Polarizers for Near Infrared Imaging on CMOS Image Sensors
Abstract
This paper presents the design, fabrication, and characterization of dielectric-based polarization-sensitive sensors, focusing on the integration of optical metasurface-based polarization routers compared to polarization filters for enhanced imaging performance. The proposed designs, fabricated on a backside-illuminated (BSI) CMOS image sensor, demonstrate high transmission and a polarization extinction ratio of 1.8 for an F/2 aperture at 940 nm. We investigate the advantages of polarization routers over traditional metallic or dielectric gratings filters highlighting their superior light collection efficiency. Experimental results show minimal spatial dispersion across the pixel matrix, confirming the robustness of the fabrication process. These results highlight the potential of on-chip dielectric polarization routers for advanced imaging applications, such as security, automotive, and medical imaging.Keywords
CMOS Image Sensor (CIS), Polarization, Degree of linear polarization (DoLP), Angle of Polarization (AoP), Polarization extinction ratio (PER), Quantum Efficiency (QE),References
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