Datalogic DS6100, Руководство по установке

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DATALOGIC DS6100
Reading Features - 3.1
3 READING FEATURES
3.1 ADVANCED CODE RECONSTRUCTION
The traditional way of barcode reading could be called "Linear Reading".
In this case, the laser beam crosses the
barcode symbol from its beginning to its
end as shown in Figure 3.1.
Figure 3.1 - Linear reading
In Advanced Code Reconstruction mode it is no
longer necessary for the laser beam to cross the
label from the start to the end. With just a set of
partial scans on the label (obtained using the motion
of the label itself), the DS6100 is able to
"reconstruct" the barcode. A typical set of partial
scans is shown in Figure 3.2.
Figure 3.2 - Partial scans
None of the partial scans contains the whole label. The decoder aligns each
partial scan correctly and combines them in order to obtain the entire code.
The alignment is performed by calculating the time difference from one
partial scan to another using a reference code element.
3.1.1 Tilt Angle for Advanced Code Reconstruction
The most important parameter in Advanced Code Reconstruction is the
value of the maximum tilt angle (
α
maximum) under which the code
reconstruction process is still possible.
We define the Tilt angle as the angle (
α
)
between the laser beam and a line parallel to
the barcode label, as shown in Figure 3.3.
Figure 3.3 - Tilt angle
α
Laser Beam
0° to
α
max
α
= tilt angle
Code Direction
Laser
Beam