Chapter
5
Operating Instructions
CLV640 Bar Code Scanner
46
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SICK AG · Division Auto Ident · Germany · All rights reserved
8011975/0000/2008-04-14
Installation
5.3.4
Avoiding surface reflections
If the light of the scanning line(s) vertically meets the surface of the bar code, this can result
in disruptive reflections when the bounced back light is received. To prevent this effect, the
bar code scanner must be installed in such a way that the light emitted is tilted down rela-
tive to the plumb line.
Fig. 5-6:
Avoiding surface reflection using the line scanner as an example: Angle between emitting light and bar code (tilted away
from the plumb line)
5.3.5
Counting direction of the reading angle and code angle
The bar code scanner can scan and decode several bar codes with every read.
The location-related reading diagnosis data is determined:
•
The reading angle from the reading window to the red scanning line of the deflected
scanning beam under which the middle of a bar code is detected can be displayed as
an RA (reading angle) value.
•
In addition, with the line scanner with oscillating mirror, the deflection angle of the
scanning line under which the bar code scanner detects the bar code on the red scan-
ning line can be displayed as a CW value.
The determination of the RA/CW value enables identical bar codes (code type, code length
and data contents) to be separated and the bar code data to be assigned to their position
on the object.
