Datalogic AV7000, Справочное руководство

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GLOSSARY
Address
A unique designation for the location of data or the identity of a smart device; allows each
device on a single communications line to respond to its own message.
Alignment
The position of a scanning or detection device in relation to the target scanning area or
receiving element. Both the barcode reader and photoelectric sensor require proper
alignment to assure optimal performance
Alphanumeric
Consisting of letters, numbers, and symbols
Ambient light
The lighting conditions in the scanning area. Ambient light can interfere with successful
scanning of bar codes
ANSI (American National Standards Institute)
The principle standards development group in the U.S. A non-profit, non-governmental group
supported by over 1000 trade organizations, professional societies, and companies. Member
body to the ISO (International Standards Organization).
Aperture
Term used on the required CDRH warning labels to describe the laser exit window.
ASCII (American Standard Code for Information Interchange)
Pronounced as-kee. A standard seven bit plus parity code, representing 256 characters,
established by ANSI to achieve compatibility between data services.
Aspect ratio
The ratio of height to width of a bar code symbol. A code twice as high as wide would have
an aspect ratio of 2; a code twice as wide as high would have an aspect ratio of ½ or 0.5.
Bar
The dark elements of a printed barcode symbol. Referred to as elements in 2D symbologies.
Barcode
A pattern of variable-width bars and spaces which represents numeric or alphanumeric data
in machine-readable form. The general format of a barcode symbol consists of a leading
margin, start character, data or message character, check character (if any), stop character,
and trailing margin. Within this framework, each recognizable symbology uses its own unique
format.
Barcode character
A single group of bars and spaces that represent an individual number, letter, or other
symbol.
Barcode density
The number of characters that can be represented in a linear unit of measure. Bar code
density is often referred to in characters per inch (CPI).