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Nara Institute, Japan paper in Optics Express shows that with advanced process of 65nm and large pixel size of 20um one can get over 35db extinction ratio polarizing pixels:
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Image sensor pixel with on-chip high extinction ratio polarizer based on 65-nm standard CMOS technology"
Kiyotaka Sasagawa, Sanshiro Shishido, Keisuke Ando, Hitoshi Matsuoka, Toshihiko Noda, Takashi Tokuda, Kiyomi Kakiuchi, and Jun Ohta
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Simulation results of metal Cu wire grid polarizer characteristics. (a) Extinction ratio spectra for different line / space sets (b) transmittance for TE and TM polarization light and extinction spectra for the finest pitch grating that can be achieved using 65nm process |
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