common corrective actions that can be attempted to remedy symbol quality
problems.
Problem: Low Symbol Contrast (SC) or PCS
Possible Causes:
•
High Minimum Reflectance (Rmin)
•
Bars too “light”
•
Incorrect verification light source
•
Low Maximum Reflectance (Rmax)
•
Dark substrate
Potential Solutions:
•
Darken bars, i.e., use a darker or more carbon-content ink, increased
amount of toner (laser), increased heat (thermal printing).
Note:
increasing heat or ink/toner coverage excessively may cause
dimensional tolerance or modulation problems.
•
Change ink/toner/ribbon to darker or barcode rated quality.
•
Check whether verification is to be done at 660 or 880 nm.
•
Note: Non-carbon-based inks and printing do not produce “black”
images for 880 nm light sources.
•
Change to lighter substrate.
Note: for direct printing on Kraft, a low
Symbol Contrast grade is to be expected. Check ANSI MH10.8 or your
application specification for guidance.
Problem: Low Minimum Edge Contrast (ECmin)
Possible Causes:
•
“Fuzzy” bar edges
•
Bars too light
•
Substrate too dark
•
Verifier aperture too large
Potential Solutions:
•
Clean printer
•
Ensure proper media/substrate match to produce crisp images.
•
Reduce pressure (wet ink printing)
•
Use a darker ink
•
Use a lighter substrate
•
Increase X dimension
•
Check for proper verifier aperture size (see Wand/Mouse Aperture
Selection Table on page 21)
Problem: Low Modulation (MOD)
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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 ...
