24
BCL 558
i
Leuze electronic
4.4
Reading techniques
4.4.1
Line scanner (single line)
A line (scan line) scans the label. Due to the opt. opening angle, the reading field width is
dependent on the read distance. Through the movement of the object, the entire bar code
is automatically transported through the scan line.
The integrated code fragment technology permits twisting of the bar code (tilt angle) within
certain limits. These are dependent on the transport speed, the scanning rate of the scanner
and the bar code properties.
Areas of application of the line scanner
The line scanner is used:
• when the bars of the bar code are printed in the conveying direction ('ladder arrange-
ment').
• with bar codes having very short bar lengths.
• when the ladder code is turned out of the vertical position (tilt angle).
• when the scanning distance is large.
Figure 4.4:
Deflection principle for the line scanner
