User Guide

WLS 8400 Product Reference Guide
GL-10
MIL 1 mil = 1 thousandth of an inch; a unit of measure
often used to quantify bar code printing and scanning
dimensions.
Misread (Misdecode) A condition which occurs when the data output of a
reader or interface controller does not agree with the
data encoded within a bar code symbol.
Module (1) The narrowest nominal width unit of measure in a
symbol. In certain symbologies, element widths are
specified as multiples of 1 module. Equivalent to X
dimension; or (2) a single cell in a matrix symbology
used to encode 1 bit of data. In MaxiCode, the module
shape is a regular hexagon. In Data Matrix, the
module shape is nominally square. In PDF417, the
module shape is a regular rectangle. In bar code
symbologies, the module shape is a regular rectangle.
Module Check Digit or Character A character within the symbol data field calculated
using modular arithmetic that is used for error
detection. The calculated character is determined by
applying a code algorithm to the data field contents
(see Check Digit).
Moving Beam Bar Code Reader A device where scanning motion is achieved by
mechanically moving the optical geometry.
MRD Minimum reflectance difference: a formula that is
used to determine if there is an adequate difference
between absorbed and reflected light.
Nanometer Unit of measure used to define the wavelength of
light that is equal to 10-9 meter.
Nominal The exact (or ideal) intended value for a specified
parameter. Tolerances are specified as positive and
negative deviations from this value.
Nominal Size Standard size for a bar code symbol. Most UPC/EAN
codes are used over a range of magnifications (e.g.,
from 0.80 to 2.00 of nominal).
Non-Contact Reader/Scanner Bar code readers requiring no physical contact with
the printed symbol.
Non-read The absence of data at the scanner output after an
attempted scan, which is due to no code, defective
code, scanner failure or operator error.