Leuze electronic
BCL 558
i
25
TNT
35/7-2
4
V
4.4.2
Line scanner with oscillating mirror
The oscillating mirror deflects the scan line additionally to both sides across the scan direc-
tion at a randomly adjustable oscillation frequency. In this way, the BCL 558
i
can also scan
larger areas or spaces for bar codes. The reading field height (and the scan line length useful
for evaluation) depends on the reading distance due to the optical beam width of the oscil-
lating mirror.
Areas of application of the line scanner with oscillating mirror
For line scanners with oscillating mirror, oscillation frequency, start/stop position etc. are
adjustable. It is used:
• when the position of the label is not fixed, e.g. on pallets – various labels can, thus,
be detected at various positions.
• when the bars of the bar code are printed perpendicular to the conveying direction
('picket fence arrangement').
• when reading stationary objects.
• when the bar code is turned out of the horizontal position.
• when the scanning distance is large.
• when a large reading field (reading window) has to be covered.
Figure 4.5:
Deflection principle for the line scanner with oscillating mirror add-on