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Code 39 barcode
is a barcode with no fixed length and can represent 43
characters, including uppercase Latin letters, numbers and some
special characters.
LOGMARS stands
for Logistics Applications of Automated Marking and Reading
Symbols. It is defined by code 39 military standard
MIL-STD-1189B.
The Code 39
barcode was developed by Dr. David Allier of Intermec in 1974
and was initially adopted by the U.S. Department of Defense as a
military barcode.
Code 39 has only
two unit widths, namely wide unit and narrow unit. The width of
the wide unit is 1 to 3 times that of the narrow unit.
Generally, 2 times, 2.5 times or 3 times are used. Each barcode
character of Code 39 consists of nine units, three of which are
wide units and the rest are narrow units, hence the name Code
39.
The Code 39
barcode was the first alphanumeric barcode and was later widely
used in industrial fields.
Because it could
handle letters, CODE 39 was indispensable in the industrial
field at the time and was used in factory automation industries
such as automobiles and electronics.
Code39 is one of
the most widely used barcode formats. Code39 is defined in the
ISO/IEC 16388:2007 standard.
Advantage:
Ability to encode
data of any length. The limitations are the length of the
printed matter and the recognition range of the barcode reader.
Supports a wide
range of devices. At present, almost all barcode reading devices
can read Code39 codes, and the same is true for printers.
Simple to
Generate. Simple development techniques can quickly generate
corresponding coded images.
Shortcoming:
The coding
density is low and cannot represent complex characters such as
Chinese. A check code is needed to improve reliability. |