WORKSHOP PAPER
A VGA Optical Filter-less CMOS Image Sensor with UV-selective and Visible Light Channels by Differential Spectral Response Pixels
Yhang Ricardo Sipauba Carvalho da Silva1, Rihito Kuroda1, Shigetoshi Sugawa1
1Graduate School of Engineering, Tohoku University, 6-6-11-811, Aza-Aoba, Aramaki, Aoba-ku, Sendai, Miyagi, Japan 980-8579

Abstract

This paper presents a newly developed CMOS image sensor (CIS) capable of capturing UV-selective and visible light images simultaneously in a single exposure, without employing band-pass filters. The developed CIS pixels are composed of high UV sensitivity and low UV sensitivity pixels, arranged alternately in a checker pattern. The UV-selective image is captured by extracting the differential spectral response between adjacent pixels, while the visible light image is captured by the low UV sensitivity pixels. The lateral overflow capacitor (LOFIC) technology was introduced in both pixel types to achieve high sensitivity and wide dynamic range simultaneously. The developed CIS exhibits 172µV/e- conversion gain, 131ke- full well capacity (FWC) and 92.3dB dynamic range. The spectral sensitivity ranges of high and low UV sensitivity pixels are 200-700nm and 370-700nm, respectively, and after the differential spectral response extraction is 200-480nm. A UV-selective sample image captured using the developed CIS is presented.
Publisher: IISS (Int. Image Sensors Society)
Year: 2019
Workshop: IISW
URL: https://doi.org/10.60928/w5di-27ne
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Keywords

CMOS Image Sensor, UV Imaging, Differential Spectral Response,

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