Matrix Vision mvBlueFOX, Техническое руководство, Страница: 153 / 255

146 CONTENTS
Figure 2: Image corrections: DefectivePixelsFilter
Note
Repeating the defective pixel corrections will accumulate the correction data which leads to a higher value in
"DefectivePixelsFound"
. If you want to reset the correction data or repeat the correction process you
have to set the (Filter-) "Mode = Reset Calibration Data" .
19.2.1.2 Dark Current Correction
Dark current is a characteristic of image sensors, which means, that image sensors also deliver signals in total
darkness by warmness, for example, which creates charge carriers spontaneously. This signal overlays the image
information. Dark current depends on two circumstances:
1. Exposure time
The longer the exposure, the greater the dark current part. I.e. using long exposure times, the dark current
itself could lead to an overexposed sensor chip
2. Temperature
By cooling the sensor chips the dark current production can be highly dropped (approx. every 6 °C the dark
current is cut in half)
MATRIX VISION GmbH