Symbol LT 1804 Product Reference Manual page 124

LT 1804 Product Reference Guide: Glossary
Print Contrast Signal
(PCS)
Programming Mode
Quiet Zone
Reflectance
Resolution
Scan Area
Scanner
Scanning Mode
Scanning Sequence
Self-Checking Code
Space
Specular Reflection
Start/Stop Character A pattern of bars and spaces that provides the scanner with start and
Substrate
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 = (RL - RD) / RL, where RL is the
reflectance factor of the background and RD the reflectance factor of
the dark bars.
The state in which a scanner is configured for parameter values. See
SCANNING MODE.
A clear space, containing no dark marks, which precedes the start
character of a bar code symbol and follows the stop character.
Amount of light returned from an illuminated surface.
The narrowest element dimension which can be distinguished by a
particular reading device or printed with a particular device or
method.
Area intended to contain a symbol.
An electronic device used to scan bar code symbols and produce a
digitized pattern that corresponds to the bars and spaces of the
symbol. Its three main components are:
1. Light source (laser or photoelectric cell) - illuminates a bar code.
2. Photodetector - registers the difference in reflected light (more light
reflected from spaces).
3. Signal conditioning circuit - transforms optical detector output into
a digitized bar pattern.
The scanner is energized, programmed, and ready to read a bar code.
A method of programming or configuring parameters for a bar code
reading system by scanning bar code menus.
A symbology that uses a checking algorithm to detect encoding errors
within the characters of a bar code symbol.
The lighter element of a bar code formed by the background between
bars.
The mirror-like reflection of light from a surface, which can "blind" a
scanner.
stop reading instructions and scanning direction. The start and stop
characters are normally to the left and right margins of a horizontal
code.
A foundation material on which a substance or image is placed.
Glossary -5