Event vision sensors with digital event detection

Abstract

Event vision sensors with digital event detection are disclosed herein. In one embodiment, an image sensor includes an EVS pixel with a photosensor, an integrating-type photo-detecting stage, and in-pixel sampling circuitry including multiple sampling nodes. An analog-to-digital converter (ADC) is coupled to the in-pixel sampling circuitry and converts analog irradiance levels into digital signals. Event detection circuitry coupled to the ADC computes event signals based on temporal contrast differences between corresponding digital signals output by the ADC and a contrast threshold. The in-pixel sampling circuitry samples integrated reference and momentary integrated signal irradiance levels during different operational phases. The event detection circuitry performs correlated double sampling operations to compute digital difference signals and asserts an event signal when the temporal contrast difference exceeds the contrast threshold.

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