Barcode Scanning
GS1 DataMatrix is a variant of the Data Matrix symbology that conforms to GS1 specifications and has been in the public domain since 1994. GS1 DataMatrix is used in the aerospace, medical device manufacturing, and pharmaceutical industries, among others, and by the US Department of Defense.
GS1 DataMatrix inherits the specifications for its character set and dimensions from Data Matrix.
Data Matrix is defined in ISO/IEC 16022 Information technology - Automatic identification and data capture techniques - Data Matrix bar code symbology specification). The GS1 implementation is defined in the GS1 General Specifications document.
Symbol Structure
The symbol comprises the following elements:
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Data regions that contain square modules in an array
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Alignment patterns (for larger symbols)
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Finder pattern
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Quiet zone border
The finder pattern around the perimeter of the symbol consists of a solid line on the left and bottom edges and a pattern of alternating black and white modules along the right and top edges.
A rectangular GS1 DataMatrix symbol can encode up to 98 digits, and a square symbol can encode up to 3,116 digits. The data region of a GS1 DataMatrix symbol always begins with the Function Code 1 (FNC1) character and uses application identifiers to separate different types of data within the barcode.
There are two types of the Data Matrix symbology, based on the error checking and correction (ECC) methods they use. Per the GS1 specification, all GS1 DataMatrix barcodes have a symbol type of ECC 200.
In symbols that are 32 x 32 modules or larger, an alignment pattern divides the symbol into four (for square symbols) or two (for rectangular symbols) data regions.
Character Set
This symbology supports the ASCII characters that are described in ISO/IEC 646 Information technology - ISO 7-bit coded character set for information interchange.
Error Correction
GS1 DataMatrix uses the Reed-Solomon algorithm for error correction, which enables the barcode to be read even if up to 20 percent of the code is damaged. This allows for greater margin for error in print quality and contrast than other symbologies.
Symbol Dimensions
The dimensions of a GS1 DataMatrix symbol depend on the amount of data that is entered. The symbol size ranges from 10 x 10 modules to 144 x 144 modules. There is always an even number of rows and columns.
GS1 DataMatrix requires a one-module-wide quiet zone on all sides.
Application Identifiers
Every GS1 symbol contains one or more application identifiers in addition to the data it encodes. An application identifier is a sequence of characters that relates a data string to a physical or logical thing, such as an item number, serial number, or due date.
Each application identifier tells the user what type of data follows and defines the length and data format of that same data string. Some application identifiers specify data fields that contain a fixed number of characters, whereas others specify a variable-length data field.
GS1 Digital Link
GS1 DataMatrix can be used to encode a GS1 Digital Link, which is a specialized Web URI that supports both product identification and a link to online material that comply with the GS1 standard. The GS1 Digital Link makes it possible for manufacturers and retailers to provide web-based product information to other businesses or to consumers.
