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PDT 7200 Series Product Reference Guide for Windows
®
CE
Scanning Options
Smart Raster Capability
All integrated 2D scan engines may be programmed for “Smart Raster” capability, which
causes the scanner to emit a raster pattern dynamically optimized to the particular PDF417
bar code’s shape. To increase scanning efficiency and optimize decode time, the scanner
determines the geometry of the bar code and opens at a rate and size optimal for decoding
that bar code.
In normal “Smart Raster” operation, a trigger pull causes a slab raster pattern to appear. If
the target is a 1-D bar code, the pattern never gets beyond a slab raster. But if the target bar
code is PDF417, the scanning patterns open up to a full, optimized raster pattern as soon as
the scanner is properly aligned over the bar code (
Figure 5-1 ).
Figure 5-1. 1-D/PDF417 Scan Element Aiming and Scanning Patterns
For best operation in smart raster mode, keep the scan pattern as parallel to the symbol’s rows
as possible, keep the scanner as still as possible, and hold the scanner at an angle which does
Aiming “Slab” Raster Pattern
Aiming “Dot” Pattern
Open Raster Pattern
Y-
A
x
is
Y-
A
x
is
Horizontal Displacement (X - Axis)