Choosing an inappropriate scanning aperture will result in inaccurate quality
measures. Too small an aperture may detect reflectance nonuniformities (spots
and voids) that would not affect scanning with a “normal” aperture size. Too large
an aperture will not be able to resolve individual elements of the symbol. This will
generally result in symbol rejection or misleading results.
Wand/Mouse Aperture Selection
WAND NUMBER
DIAMETER IN .001” (mm)
SYMBOL
“X” DIMENSION RANGE
03
(0.076 mm)
0.004”
≤
X < 0.007"
0.102 mm
≤
X < 0.178 mm
05
(0.127 mm)
0.0071”
≤
X < .013
0.178 mm
≤
X < 0.330 mm
10
(0.254 mm)
0.0131”
≤
X < 0.025"
0.330 mm
≤
X < 0.635 mm
20
(0.508 mm)
0.0251” and larger
0.635 mm
≤
X < 0.178 mm
Note: 6 mm aperture specified for UPC / EAN
Some application standards recommend a 0.010 inch aperture for all symbol
verification. Other standards specify a different aperture. Check the application
standard's requirements.
If no aperture is specified, use the aperture that is as close to, but not larger than,
80% of the narrow element width.
Light Source: Hand Held Products also offers wands with both visible red (660
nm) and infrared (880 nm) light sources. Most industry standards require
verification at 660 nm (visible red). However, some applications (especially ID
badges with security overlays) require verification in the infrared.
If there is no applicable application standard, choose the light source that
matches the scanner that will read the symbol (if known).
If necessary, calibrate the verifier. If you have removed a wand, even if you
reattach the same one, the program will require you to recalibrate. Find the
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Summary of Contents for Quick Check PC600
Page 1: ...Quick Check PC600 Bar Code Verifier User s Guide ...
Page 6: ...5 ...
