Skew
Rotation about the Y-axis. Rotational deviation from correct horizontal and vertical
orientation; may apply to single character, line or entire encoded item. See pars. 2.2
and 2.5.
Step-Ladder orientation
When the barcode’s bars are positioned horizontally on the product, causing them to
appear as a ladder. The ends of all bars will enter the scan window first. See par.
3.2.1.
Symbol
A combination of characters including start/stop and checksum characters, as
required, that form a complete scannable barcode.
Tilt
Rotation around the Z axis. Used to describe the position of the barcode with respect
to the laser scan line. See pars. 2.2 and 2.5.
Trigger Signal
A signal, typically provided by a photoelectric sensor or proximity switch, which
informs the scanner of the presence of an object within its reading zone.
UPC
Acronym for Universal Product Code. The standard barcode type for retail food
packaging in the United States.
Visible Laser Diode
A light source used in scanners to illuminate the barcode symbol. Generates visible
red light at wavelengths between 630 and 680 nm.
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