Chapter
4
Operating Instructions
CLV 480 Bar Code Scanner
4-4
©
SICK AG · Division Auto Ident · Germany · All rights reserved
8 010 080/O824/10-02-2005
Installation
4.2.7
Distance between the CLV and the bar code
Basic alignment between the CLV and the bar code
Depending on the application, the line scanner or line scanner with oscillating mirror versions
of the CLV is used.
shows how the device is aligned with the bar code on the object
for each of the two scanning methods.
Reading distance from the bar code and aperture angle
α
The distance between the reading window of the CLV and the bar code must not exceed
the technical limits. The height of the reading field is shown as a function of the reading
distance for various resolutions (module widths) depending on the CLV type in
Specification diagrams, Page 10-1
.
shows the definition of the reading distance a (radial measured) from the reading
window and of the aperture angle
α
each of the two scanning methods.
The useful aperture angle is typically
60
°
for the line scanner and max.
50
°
for the line scan-
ner with oscillating mirror. Due to the V-principle of beam deflection, the reading field height
(for evaluating the useful length of the scan line) depends on the readling distance.
Fig. 4-4:
Scanning methods: alignment with bar code and conveyor direction
Line scanner
Line scanner with
oscillating mirror
Fig. 4-5:
Definition of the reading distance a and of the aperture angle
α
α
105
°
α
Line scanner
Line scanner with oscillating mirror
Reading distance a
Reading distance a
