© SICK AG • Auto Ident • Germany • All rights reserved
14
Operating Instructions
8 008 224/I982/08-00
CLV 41x Bar Code Scanner
Fig. 9. Scanning method alignment relative to the bar code and conveyor direction
Line scanner
Raster scanner
Reading angle and distance
When mounting the device, ensure that all of the possible reading angles at which the
bar code can be positioned relative to the scan line are taken into account.
Fig. 10
shows this using a line scanner as an example. The reading window and code should
be almost parallel, whereby total surface reflection (see below) should be avoided.
Fig. 10. Mounting example of CLV with line scanner: reading angles taken into account
α:
Tilt
β:
Pitch
γ:
Skew
Reading
distance
Reading
range
β
α
γ
The following angle limits should not be exceeded (CLV):
Angle
Tilt
α
Pitch
β
Skew
γ
Limit value
15° (depening on code print)
45°
45°
Table 10
When selecting the mounting location for the device, the limit values of the reading
range for the selected bar code resolution and the useful aperture angle (max. 60°
with front light emission) must be taken into account. See also Section
16. Reading
field diagrams.
Avoiding surface reflection
If the reading beam strikes the surface of the bar code vertically, reflection
interference may be caused when the returned light is received.
Ø
Mount the CLV with front light emission (a) in such a way that the scan line(s) strike
the bar code at an angle less than approx. 15° from the vertical reference (
Fig. 11
).
Ø
The CLV with lateral light emission (b) must be mounted flush so that the scan line
is emitted at an angle less than 105° relative to the housing.