Chapter
4
Operating Instructions
CLV 45x Bar Code Scanner
4-6
©
SICK AG · Division Auto Ident · Germany · All rights reserved
8 009 139/K949/06-06-2002
Installation
Avoiding surface reflections
If the light of the scan line falls exactly vertically on the surface of the bar code, disturbing
reflections can occur when the reflected light is received. In order to avoid this effect the
CLV must be installed so that the emitted light is tilted relative to the perpendicular.
At the line scanner with oscillating mirror the laser beam is emitted during oscillating mode
at an angle of 105
°
to the housing during the pass through the neutral position CW = 50).
The device can only be mounted flush to the edge at the transport unit if the deflection ran-
ges of the oscillating mirror is small. Otherwise the device also has to be mounted at an ang-
le of inclination of 15 in order to attain symmetrical deflection ranges.
4.2.8
Counting direction of the code position CP and of the code angle CW
Explanation
The CLV can scan and decode several bar codes during every reading.
In the process it determines the local reading diagnostic data for each bar code:
•
The position (CP value) of the bar code center within the scan line
•
In addition in case of a scanning process with oscillating mirror the deflection angle of
the scan line (CW value) under which the bar code center is detected
shows the counting direction of the code position and of the code angle.
The determination of the two data allow identical bar codes (code type, code length and
data contents) to be separated as well as the local assignment of the bar code data in the
read result to its position on the object.
Fig. 4-8:
Avoiding surface reflections: Angle between the emitted light and the bar code (tilted
away from the perpendicular)
Line scanner
(front-end reading window)
Line scanner with oscillating mirror
(side-end reading window)
(top view)
(side view)
