Global Shutter CMOS Vision Sensors and Event Cameras for On-Chip Dynamic
Information
Abstract
The on-chip extraction of dynamic information from a scene can be
addressed with either frame-based CMOS vision, also called smart image
sensors, or with dynamic vision sensors, also known as event cameras.
When implemented with a pinned photodiode (PPD) as 4-transistor active
pixel sensors (4T-APS) the former brings about the benefit of low
temporal noise and dark current but without high dynamic range (HDR).
The latter comes with the benefits of HDR and fast event detection rate
at a low power consumption. The drawback is the background activity
noise, which leads to additional hardware or algorithms to keep it low.
In essence, the taxonomy of dynamic information extraction with image
sensors is that of global shutter solutions and event cameras, each of
which with their pros and cons. This paper digs in such differences and
similarities focused on mismatch and noise through a global shutter
4T-APS implementation with local HDR incorporated in 180 nm CMOS
technology vs conventional logarithmic event sensors found in the
literature.