Data Matrix is a two-dimensional (2D) symbol laid out in a square or rectangular grid. Data is encoded on both the x and y axes in a series of dark and light blocks. Therefore, Data Matrix symbols are not read with laser scanners, but rather with imagers, CCDs or other camera-based products that can "read" data contained in an area rather than a line. Symbols can be created with a variety of direct part marking (DPM) techniques and printed on labels and nameplates. Information capacity, compactness and generous reading tolerance sets Data Matrix apart from other barcode symbologies.
The data carrying capacity of Data Matrix helps make it extremely reliable. The symbology standard for Data Matrix includes provisions for encoding error detection and correction algorithms, which the user can set at different levels. As a result, Data Matrix symbols with scratches, tears, holes and stains can be successfully read without data loss, even if more than 20 percent of the symbol were to become damaged and unreadable.
Data Matrix can be read at lower contrast ratios than most barcode symbologies, which is a helpful feature for environments where symbols may be obscured by grease, dirt, paint and chemical coatings, and when the symbology is applied to metal and other reflective surfaces.