Hardware validated unified model of multibit temporally and spatially oversampled image sensors with conditional reset

Abstract

We describe a photon statistics-based theoretical model of the response to incident light of an image sensor and show that conditional reset and multibit temporal oversampling increase the dynamic range significantly. This photon-based modeling approach describes the full image sensor design space of temporal and spatial oversampling either with a binary comparison or with a multibit read of each sample. We find excellent quantitative agreement between measurements on custom hardware and our theoretical predictions. We then use this model to show what improvements in dynamic range and low-light response can be achieved by oversampling and what the limits of improvement caused by pixel size and lens parameters are.