What Is a Global Shutter?
Global shutter image sensors expose all pixels simultaneously, so the entire frame represents the same moment in time. The captured signal is then stored and read out from the sensor.
What Is a Rolling Shutter?
Rolling Shutter sensors are the standard sensors for most high volume applications, including automotive. They expose and read out one or several lines of pixels in a sensor at a time in a line-by-line order, creating a “windowing” aperture that sweeps across the sensor from top to bottom.
When to Consider a Global Shutter Camera
A global shutter has a much better ability to accurately freeze fast motion. A rolling shutter will have motion artifacts that appear as “shear” or distortion of moving objects, or the entire scene can shear if the camera itself is moving. This effect can be acutely visible in rotating objects.
Disadvantages of Rolling Shutter Sensors
Misshapen fast moving objects, horizontal banding visible in flat fields from mains or LED frequency beating against the “line rate”, inability to use a strobe (such as for traffic cameras).
Disadvantages of Global Shutter Sensors
Lower sensitivity and higher noise than comparable rolling-shutter sensors. Costs are typically higher due to additional pixel circuitry, the silicon area required for on-sensor data storage, and lower economies of scale.
D3 Embedded offers both rolling-shutter and global-shutter camera modules, and can help select the right image sensor, optics, interface, and processing platform, as well as perform ISP tuning for your application.
