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 circuit branches. 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 (i) temporal contrast differences between corresponding digital signals output by the ADC and (ii) a contrast threshold. The in-pixel sampling circuitry can include branches for sampling momentary integrated signal irradiance levels and integrated reference irradiance levels. The event detection circuitry can assert event signals when temporal contrast differences exceed the threshold, indicating event detection during an exposure period.

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