Operating principle
Leuze electronic
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3.2
Limits of light section sensors
3.2.1
Occlusion
The detection of high and wide objects from just one point poses the particular problem
that depending on the object contour, parts of the object may be obscured by others. This
effect is called occlusion.
The Figure 3.2 illustrates the problem:
Figure 3.2:
Occlusion
-Y
Z
+X
-X
Laser occlusion
Receiver occlusion
In the red areas the laser does not
strike the object. Thus it is not possi-
ble to determine any data here.
The receiver does not "see" any object contours in the
red area because they are obscured by the upper right
edge of the object.
When the object is shifted to the left the object con-
tour will still be detected by the laser but the laser line
does not lie within the receiver's field of view at that
point, and therefore no measurement values can be
detected.
