Basler Vision Technologies Sprint Series, User Manual

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Line Acquisition Modes
62 Basler sprint Mono Cameras
If an encoder is used but it is not set-up correctly, haloing in the transport direction will result. In this
case, the halos will be constant in size.
Conveyor Travel
The conveyor must travel in a straight line. If the conveyor motion is not straight, each line in the
sensor will scan a different area of the object. This situation will cause haloing that is perpendicular
to the transport direction. The halos will vary in size.
Sensor Perpendicularity
The sensor lines in the camera must be perpendicular to the conveyor’s line of travel. If the sensor
lines are not perpendicular to the line of travel, a slightly different area of the object will fall on each
line. This situation will cause haloing that is perpendicular to the transport direction. The halos will
be constant in size.
Sensor-Conveyor Parallelism
The face of the sensor in the camera and the surface of the conveyor should be in parallel planes.
This condition should be met to ensure that all of the pixels in the sensor lines view the object at the
same magnification.
If the camera is positioned so that the sensor is rotated on its short axis, you will see haloing in the
transport direction. And if the camera is positioned so that the sensor is rotated on its long axis, you
will see haloing that is perpendicular to the transport direction.
If your system design will not allow you to achieve sensor-to-conveyor parallelism, a telecentric lens
setup can be used to overcome the problems that this will cause. A telecentric setup usually
requires high illumination.