SciDVS: A Scientific Event Camera with 1.7% Temporal Contrast Sensitivity at 0.7 lux

TL;DR

This paper introduces SciDVS, a highly sensitive scientific event camera that operates effectively in low-light conditions, achieving 1.7% sensitivity at 0.7 lux with novel in-pixel amplification and adjustable resolution.

Contribution

The paper presents a new DVS prototype with significantly enhanced sensitivity and HDR capabilities, utilizing novel in-pixel preamplifiers and adjustable pixel binning for scientific applications.

Findings

Achieves 1.7% sensitivity at 0.7 lux illumination.

Provides intrascene HDR and increased sensitivity.

Enables trade-off between spatial resolution and sensitivity.

Abstract

This paper reports a Dynamic Vision Sensor (DVS) event camera that is 6x more sensitive at 14x lower illumination than existing commercial and prototype cameras. Event cameras output a sparse stream of brightness change events. Their high dynamic range (HDR), quick response, and high temporal resolution provide key advantages for scientific applications that involve low lighting conditions and sparse visual events. However, current DVS are hindered by low sensitivity, resulting from shot noise and pixel-to-pixel mismatch. Commercial DVS have a minimum brightness change threshold of >10%. Sensitive prototypes achieved as low as 1%, but required kilo-lux illumination. Our SciDVS prototype fabricated in a 180nm CMOS image sensor process achieves 1.7% sensitivity at chip illumination of 0.7 lx and 18 Hz bandwidth. Novel features of SciDVS are (1) an auto-centering in-pixel preamplifier providing intrascene HDR and increased sensitivity, (2) improved control of bandwidth to limit shot noise, and (3) optional pixel binning, allowing the user to trade spatial resolution for sensitivity.