Scanning Considerations - Motorola MT2070 User Manual

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Scanning Considerations

Scanning is a simple matter of aim, scan and decode. However, to optimize scanning performance consider the
range and the scanning angle:
•
Range
Any scanning device decodes well over a particular working range — minimum and maximum distances from
the bar code. This range varies according to bar code density and scanning device optics.
Scanning within range brings quick and constant decodes; scanning too close or too far away prevents
decodes. Move the device closer and further away to find the right working range for the bar codes being
scanned. However, the situation is complicated by the availability of various integrated scanning modules.
The best way to specify the appropriate working range per bar code density is through a chart called a
decode zone for each scan module. A decode zone simply plots working range as a function of minimum
element widths of bar code symbols.
•
Angle
Scanning angle is important for promoting quick decodes. When laser beams reflect directly back into the
device from the bar code, this specular reflection can "blind" the device.
To avoid this, scan the bar code so that the beam does not bounce directly back. But don't scan at too sharp
an angle; the device needs to collect scattered reflections from the scan to make a successful decode.
Practice quickly shows what tolerances to work within.
NOTE Contact Motorola Solutions Support if persistent scanning difficulties develop. Decoding properly printed
bar codes should be quick and effortless.
NOTE It is recommended that power is applied to the device while in Intellistand.