title: Digital pixel sensor array with logarithmic delta-sigma architecture.
abstract: Like the human eye, logarithmic image sensors achieve wide dynamic range easily at video rates, but, unlike the human eye, they suffer from low peak signal-to-noise-and-distortion ratios (PSNDRs). To improve the PSNDR, we propose integrating a delta-sigma analog-to-digital converter (ADC) in each pixel. An image sensor employing this architecture is designed, built and tested in 0.18 micron complementary metal-oxide-semiconductor (CMOS) technology. It achieves a PSNDR better than state-of-the-art logarithmic sensors and comparable to the human eye. As the approach concerns an array of many ADCs, we use a small-area low-power delta-sigma design. For scalability, each pixel has its own decimator. The prototype is compared to a variety of other image sensors, linear and nonlinear, from industry and academia.
authors: Department of Electrical and Computer Engineering, University of Alberta, Edmonton, AB, Canada. mahmoodi@ualberta.ca
authors: Alireza
authors: A
authors: Mahmoodi
authors: Jing
authors: J
authors: Li
authors: Dileepan
authors: D
authors: Joseph
mesh_terms: D000703:Analog-Digital Conversion; D032701:Biomimetics / Q000295:instrumentation*; D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006801:Humans; D009799:Ocular Physiological Phenomena; D010781:Photography / Q000295:instrumentation*; D012666:Semiconductors; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation*; D014159:Transducers
references: Sensors (Basel). 2011;11(5):4512-38
references: 22163860