emitter, typically in the range of 880nm (infrared laser diodes) to 633nm (He-Ne
lasers).
wide/narrow ratio:
In a two-width symbology, the ratio of the widths of wider
elements in a symbol to those of the narrow elements.
width code:
One of two fundamental ways (see "delta code") of encoding
information in a one-dimensional medium. Each bit is assigned to a bar or space
where if that element is wide the bit value is "1" and if narrow the bit value is "0".
Also referred to as a “binary code.” Code 39 and Codabar are width codes.
Compare to “delta code”.
width error:
The difference between nominal and measured bar (or space)
widths, calculated from the scanner’s digital output or the optically measured bar
(space) widths.
X dimension:
The specified width of the narrow elements in a machine-
readable symbol. See “Z dimension.”
Y dimension:
The specified height of the elements in a machine-readable
symbol. See “bar height.”
Z dimension:
The average achieved width of the narrow elements in a
machine-readable symbol. It is equal to half the sum of the average narrow bar
width and the average narrow space width, in two-width symbologies, or to the
quotient of the average overall character width divided by the number of modules
per character in modular symbologies.
zero suppression:
The technique used to shorten U.P.C. codes by omitting
certain zeroes from the bar code symbol.
Additional Sources of Information
ANSI specifications for all bar code symbologies except U.P.C. are available
from:
AIM North America
125 Warrendale-Bayne Road.
Warrendale, PA 15086
Tel: 724 934 5688
Fax: 724 934 4495
Website:
www.aimusa.org
AIM United Kingdom
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