WORKSHOP PAPER
A Short-Pulse Indirect ToF Imager Using 6-Tap Pixel with Backside Illuminated Structure for High-Speed Charge Demodulation
Abstract
This paper presents a short-pulse indirect time-of-flight (SP iToF) sensor using 6-tap pixels with a backside illuminated structure (BSI). The BSI sensor demonstrates a fast response to near infrared (NIR) light and achieves high depth linearity and resolution over a range of 3-28 meters indoors. The paper compares 6-tap iToF sensors with front-side illumination (FSI) and BSI structures, showing that the BSI structure provides a faster response to NIR light. The SP iToF pixel contains a photodiode and a charge demodulator, with six gates (G1 to G6) and one drain (GD). Detailed measurements of the iToF sensor response using a short pulse laser show that BSI sensors have significantly smaller time constants compared to FSI sensors.Keywords
short-pulse, indirect time-of-flight, sensor, 6-tap pixel, backside illuminated structure, high-speed charge demodulation, photodiode, BSI, FSI,References
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