Information about datamatrix
A Data Matrix code is a two-dimensional matrix barcode consisting of black
and white "cells" or modules arranged in either a square or rectangular pattern.
The information to be encoded can be text or raw data. Usual data size is from a
few bytes up to 2 kilobytes. The length of the encoded data depends on the
symbol dimension used. Error correction codes are added to increase symbol
strength: even if they are partially damaged, they can still be read. A Data
Matrix symbol can store up to 2,335 alphanumeric characters.
Data Matrix symbols are rectangular in shape and usually square, they are
made of cells: little elements that represent bits. Depending on the situation a
"light" module is a 0 and a "dark" module is a 1, or vice versa. Every Data
Matrix is composed of two solid adjacent borders in an "L" shape (called the
"finder pattern") and two other borders consisting of alternating dark and light
"cells" or modules (called the "timing pattern"). Within these borders are rows
and columns of cells encoding information. The finder pattern is used to locate
and orient the symbol while the timing pattern provides a count of the number of
rows and columns in the symbol. As more data is encoded in the symbol, the
number of cells (rows and columns) will increase. Symbol sizes vary from 8×8 to
144×144.
The most popular application for Data Matrix is marking small items, due to
the code’s ability to encode fifty characters in a symbol that is readable at 2
or 3 mm2 and the fact that the code can be read with only a 20% contrast ratio.
The Data Matrix is scalable, with commercial applications as small as 300
micrometres (laser etched on a 600 micrometre silicon device) and as large as a
1 metre (3 ft) square (painted on the roof of a boxcar). Fidelity of the marking
and reading systems are the only limitation.
The Electronic Industries Alliance (EIA) recommends using Data Matrix for
labeling small electronic components[1].
Data Matrix codes are part of a new traceability drive in many industries,
particularly aerospace where quality control is tight and a black market exists
for counterfeit or non-serviceable parts. Data Matrix codes (and accompanying
alpha-numeric data) identify details of the component, including manufacturer
ID, part number and a unique serial number. The US Department of Defense has
selected Data Matrix for the mandatory unique identification of certain assets
it procures for all of the services. Items from individual weapons to critical
components of major systems must be permanently marked with a unique data matrix
code in accordance with standards in Military Standard 130. Much of the
Aerospace Industry, especially members of the Air Transport Association (ATA),
aims to have all components of every new aircraft identified by Data Matrix
codes within a tight deadline.[2]
The Data Matrix format is used by Semacode to encode 4096 bits RSA private
keys that can be read by cameras or scanners.
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