Symbol LT 1806 Product Reference Manual page 98

LT 1806 Product Reference Guide: Glossary
CDRH
CDRH Class 1
CDRH Class 2
Character
Character Set
Check Digit
Codabar
Code 128
Code 3 of 9 (Code 39) A versatile and widely used alphanumeric bar code symbology with
Code 93
Code Length
Continuous Code
Center for Devices and Radiological Health. A federal agency
responsible for regulating laser product safety. This agency specifies
various laser operation classes based on power output during
operation.
This is the lowest power CDRH laser classification. This class is
considered intrinsically safe, even if all laser output were directed
into the eye's pupil. There are no special operating procedures for this
class.
No additional software mechanisms are needed to conform to this
limit. Laser operation in this class poses no danger for unintentional
direct human exposure.
A pattern of bars and spaces which either directly represents data or
indicates a control function, such as a number, letter, punctuation
mark, or communications control contained in a message.
Those characters available for encodation in a particular bar code
symbology.
A digit used to verify a correct symbol decode. The scanner inserts the
decoded data into an arithmetic formula and checks that the resulting
number matches the encoded check digit. Check digits are required
for UPC but are optional for other symbologies. Using check digits
decreases the chance of substitution errors when a symbol is decoded.
A discrete self-checking code with a character set consisting of digits
0 to 9 and six additional characters: ( - $ : / , +).
A high density symbology which allows the controller to encode all
128 ASCII characters without adding extra symbol elements.
a set of 43 character types, including all uppercase letters, numerals
from 0 to 9, and 7 special characters (- . / + % $ and space). The code
name is derived from the fact that 3 of 9 elements representing a
character are wide, while the remaining 6 are narrow.
An industrial symbology compatible with Code 39 but offering a full
character ASCII set and a higher coding density than Code 39.
Number of data characters in a bar code between the start and stop
characters, not including those characters.
A bar code or symbol in which all spaces within the symbol are parts
of characters. There are no intercharacter gaps in a continuous code.
The absence of gaps allows for greater information density.
Glossary -2