IDS uEye series User Manual page 31

6 Camera Basics
Rolling Shutter
With the rolling shutter method, the pixel rows are reset and exposed one row after another. At the
end of the exposure, the lines are read out sequentially. As this results in a time delay between the
exposure of the first and the last sensor rows, captured images of moving objects are distorted.
To counteract this effect, the uEye software provides a Global Flash window where you set the time
by which flash activation is delayed. You can also specify the flash duration. This allows
implementing a global flash functionality which exposes all rows of a rolling shutter sensor
simultaneously.
Rolling shutter sensors offer a higher pixel density compared to global shutter CMOS sensors. The
rolling shutter system is used in uEye cameras with high-resolution CMOS sensors.
Figure 31: Rolling shutter sensor in live mode
Figure 32: Rolling shutter sensor in live mode with glob al flash window
)
* Optional flash function. The start time and duration are defined by the Flash delay and Duration
parameters (see also Camera Settings: I/O).
Rolling Shutter with Global Start
Some rolling shutter sensors also provide a global start mode, which starts exposure of all rows
simultaneously (see illustration). For best results, use a flash for this mode. No light is allowed to fall
on the sensor outside the flash period because otherwise the image brightness will be distributed
unevenly.
© 2009 IDS Imaging Development Systems GmbH 31