WORKSHOP PAPER
A 120dB DR and 5µm pixel pitch imager based on local integration time adaptation
Abstract
In order to preserve details in both very dark and very bright parts of the image, numerous imaging applications require the acquisition of High Dynamic Range (HDR) images, typically above 100dB. The presented work introduces a new HDR architecture implemented in an 800x512 proof-of-concept imager with a 5µm pixel pitch, featuring a 120dB dynamic range without modifying the specifications of the primary imager. This is achieved using a classic 0.18µm process and dividing the pixel array into blocks, each with its own self-adjusted integration time, based on local light conditions.Keywords
High Dynamic Range, Pixel Pitch, Integration Time Adaptation,References
1) Chen, Y. ; Xu, Y. ; Chae, Y. ; Mierop, A. ; Wang, X. ; Theuwissen, A, "A 0.7e−rms-temporal-readout-noise CMOS image sensor for low-light-level imaging", ISSCC, 2012. https://doi.org/10.1109/isscc.2012.6177059
2) Ruedi, P.-F. ; Heim, P. ; Gyger, S. ; Kaess, F. ; Arm, C. ; Caseiro, R. ; Nagel, J.-L. ; Todeschini, S., "An SoC combining a 132dB QVGA pixel array and a 32b DSP/MCU processor for vision applications", ISSCC, 2009. https://doi.org/10.1109/isscc.2009.4977300
3) Sugawa, S.; Akahane, N.; Adachi, S.; Mori, K.; Ishiuchi, T.; Mizobuchi, K., "A 100 dB dynamic range CMOS image sensor using a lateral overflow integration capacitor", ISSCC, 2005. https://doi.org/10.1109/isscc.2005.1494014
4) Solhusvik, J.et al, "A 1280x960 3.75um pixel CMOS imager with Triple Exposure HDR", Proc. IISW, Bergen, 2009. https://doi.org/10.60928/qhsc-a8mj
5) Yasutomi, K.; Itoh, S.; Kawahito, S., "A 2.7e- temporal noise 99.7% shutter efficiency 92dB dynamic range CMOS image sensor with dual global shutter pixels", ISSCC, 2010. https://doi.org/10.1109/isscc.2010.5433976
6) David X. D. Yang and Abbas El Gamal, "Comparative analysis of SNR for image sensors with enhanced dynamic range", Proc. SPIE 3649, 1999. https://doi.org/10.1117/12.347075