Symbol LS4000P Series, Product Reference Manual

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Glossary-4
LS 4000P Series Product Reference Guide
Interleaved Bar Code A bar code in which characters are paired together, using bars to represent the
first character and the intervening spaces to represent the second.
Interleaved 2 of 5 A binary bar code symbology representing character pairs in groups of five
bars and five interleaved spaces. Interleaving provides for greater information
density. The location of wide elements (bar/spaces) within each group
determines which characters are encoded. This continuous code type uses no
intercharacter spaces. Only numeric (0 to 9) and START/STOP characters may
be encoded.
LASER - Light
Amplification by
Stimulated Emission
of Radiation The laser is an intense light source. Light from a laser is all the same frequency,
unlike the output of an incandescent bulb. Laser light is typically coherent and
has a high energy density.
Laser Diode A gallium-arsenide semiconductor type of laser connected to a power source
to generate a laser beam. This laser type is a compact source of coherent light.
LED Indicator A semiconductor diode (LED - Light Emitting Diode) used as an indicator,
often in digital displays. The semiconductor uses applied voltage to produce
light of a certain frequency determined by the semiconductor's particular
chemical composition.
MIL 1 mil = 1 thousandth of an inch.
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.
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 can be used over
a range of magnifications (e.g., from 0.80 to 2.00 of nominal).
Parameter A variable that can have different values assigned to it.
Percent Decode The average probability that a single scan of a bar code would result in a
successful decode. In a well-designed bar code scanning system, that
probability should approach near 100%.
Print Contrast Signal
(PCS) Measurement of the contrast (brightness difference) between the bars and
spaces of a symbol. A minimum PCS value is needed for a bar code symbol to
be scannable. PCS = (R
L
- R
D
) / R
L
, where R
L
is the reflectance factor of the
background and R
D
the reflectance factor of the dark bars.
Programming Mode The state in which a scanner is configured for parameter values. See
SCANNING MODE.
Quiet Zone A clear space, containing no dark marks, which precedes the start character of
a bar code symbol and follows the stop character.