DataMatrix 2D barcode 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 DataMatrix 2D barcode symbol can store up to 2,335 alphanumeric characters.
DataMatrix 2D barcode 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 DataMatrix 2D barcode 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.
Conventional one-dimensional 1D barcodes are widely used in many retail and industrial applications today. However, conventional barcodes have some inherent limitations, which prevent their use in identifying and tracking products as they are manufactured. The most important such limitation is that bar codes require precise, high-contrast printing, typically on labels, in order to be read reliably, because they encode information in an analog fashion in the form of alternating bars and spaces of varying widths.
Two-dimensional 2D barcode symbologies like DataMatrix overcome this key limitation by encoding information digitally in the form of a checkerboard pattern of on/off cells and thus allow marking and reliable reading of low-contrast codes directly on parts without a label.
Data Matrix is the most popular 2D barcode symbology which has found extensive use in automotive, aerospace, electronics, semiconductor, medical devices and other manufacturing unit-level traceability applications. Data Matrix codes are typically not replacing conventional barcodes in these applications but instead extend barcode applicability to areas where they have not been applied in the past.
Data Matrix symbology was invented by Acuity CiMatrix but has been placed in the public domain so that anyone can print or read Data Matrix codes without paying a license.
Any Data Matrix symbol is comprised of the following major components:
- The L-shaped solid border
- The broken border on the opposite corner
- The data storage area inside the symbol and
- The quite zone outside of the symbol
Complete data matrix symbol
Data Matrix Code Advantages
In summary, specific advantages of Data Matrix codes over conventional 1D barcodes include:
Encode information digitally, as opposed to the analog encoding of data in conventional barcodes.
Can accommodate low-contrast printing directly on parts without requiring a label
Offer very high information density - the highest among other common 2D codes, which means that you can place a lot of information in a very small area.
They are scaleable, which means that you can print them and read them in various levels of magnification - only limited by the resolution of the available printing and imaging techniques.
Due to the high information density inherent to Data Matrix codes, they also offer built-in error-correction techniques which allow fully recovering the message encoded in a Data Matrix 2D barcode symbol even if the mark is damaged and missing as much as 20% of the symbol.
- They are read by video cameras as opposed to a scanned laser beam used for reading conventional barcodes, which means that they can be read in any orientation.
Data Matrix codes can in general store up to 3116 numeric or 2335 alphanumeric characters or up to 1555 bytes of binary information.