User's Manual

APPENDIX C BARCODE LABEL SPECIFICATIONS
All barcode symbols/labels should satisfy the appropriate AIM Uniform Symbology Specification.
Note: The CHS 8Ci can also scan barcodes on device screens.
B ACKGROUND S UBSTRATE :
The barcode symbol should be printed on material (media) that is reflective and has a matte (not glossy)
finish. A background diffuse reflectance of at least 70% to 80% is desirable for optimum contrast. Retro-
reflective media should be used to obtain decode distances greater than 36 inches.
I NK C OLOR AND T YPE :
The inked bars should not exceed 25% reflectance at the wavelength that is being used for reading,
whether printed with black ink or colored ink. The reflectance value should not vary more than 5%
within the same character.
V OIDS AND S PECKS :
The code should be printed clearly, free of voids, specks, blemishes and lines that could “fool” the
scanner. Specks or blemishes in the white spaces, or false or missing bar sections could be interpreted
by the reading equipment as part of the code. Generally, the width of such flaws is more serious than
the height. Code symbols/ labels should be rejected if these defects are present.
D EFINITION :
The bars in the barcode symbol should be well defined. Their edges should not be rough or fuzzy, so that
the bars and spaces have the proper widths intended for the barcode symbology used.
C ONTRAST :
Background reflectance (that of the substrate on which the codes are printed) should always provide a
good contrast relative to the ink reflectance (that of the code bars). The difference between the two
should be at least 37.5% at the wavelength used for reading.
T OLERANCE :
The ratio of the widths of bars and spaces in a barcode symbol must conform to the appropriate AIM
barcode specifications and can cause problems if not correct throughout the barcode. Problems can
occur when bar edges are smeared or rough, or when they exhibit voids.