User Manual - twentynine
5.2
Brightness and Sensor Signal Control
5.2.1
Exposure / Integration Time
The brightness of an image is influenced by the amount of light that falls on the image sensor, concerning
both intensity and duration. The duration of time in which the photosensitive cells of the image sensor are
exposed to the incoming light is called the exposure time or the integration time. While the intensity of
light depends on the light source and the lens aperture, the exposure time can be controlled by modifying
parameters of the camera.
Figure 32 demonstrates two settings of camera’s exposure time. The picture on the left is captured with an
exposure time of 10000
µ
s. For the picture on the right the exposure time is set to 22000
µ
s. The brightness
difference of the two images is clearly visible. Due to the nearly linear behavior of the used sensors, doubling
the exposure time results in an approximately doubled pixel intensity.
Figure 32: Different exposure time settings
The exposure time for SMARTEK Vision digital cameras is configurable by the GenICam
Float
property
ExposureTime and is expressed in microseconds (
µ
s). Each camera has a predefined range of values,
depending on the sensor and its technology.
45
SMARTEK Vision | User Manual - twentynine | Doc. v1.0.2
