Data Identifier   Data Matrix
A compliance marking term. Message prefixes in a bar code that define the general category or intended use of the data that follows.
Two-dimensional matrix bar code consisting of black and white squares arranged in a square or rectangular pattern. The information to be encoded can be text or raw data. Error correction added to increase symbol strength allow the codes to be read even if they are partially damaged.
Distribution Center . When goods are shipped to a distribution center, the container marking specifications are usually different from those required when shipping directly to a store.
Data Communications Equipment. Hardware interface standard for modems, protocol converters, and other communications equipment. To interface DCE devices with DTE (Data Terminal Equipment) devices such as terminals or PCs, a straight through serial cable is required. See also DTE.
Decoder   Depth of Field
As part of a bar code reading system, the electronics that process the signals from the scanner, interpret the signals into meaningful data, and control the interface to other devices.
The distance between the maximum and minimum surface in which a scanner is capable of reading bar codes of a specified X dimension.
DI   Die Cut
A compliance marking term. See Data Identifier.
Type of label supply used in on demand applications. See also butt cut.
Diffuse Reflection   Direct Thermal
A bar code verification term. The component of reflected light that emanates in all directions from the reflecting surface (as opposed to the focused light of the scanner laser reflected back to the scanner).
A printing method where dots are selectively heated and cooled and dragged upon heat-sensitive paper. The paper turns dark in the heated areas.
DoD   Dot Matrix
The United States Department of Defense. The DoD mandates RFID tags on certain supplies for tracking and security.
A system of impact printing where individual dots are printed by tiny wires striking the supply through an inked ribbon.
Direct Part Marking. A technology used to produce two different surface conditions on an item, effectively creating a bar code by laser etching, molding, etc. DPM is required by the DoD for certain parts and assemblies.
Dots Per Inch. Used in comparing relative printing resolution of thermal printheads and laser print engines.
Direct Store Delivery. When goods are shipped directly to a store, the container marking specifications are usually different from those required when shipping to a distribution center.
Data Terminal Equipment. Hardware interface standard for display stations, personal computers, printers and other non-communications equipment. To interface a DTE printer with a DTE device such as a PC or a display station, a null-modem serial cable is required. See also DCE.
Dual Di-Pole   DUN-14
A bidirectional tag with two antennas, making it less sensitive to orientation, thereby increasing read capability.
A special version of Interleaved 2 of 5. It always has a fixied length of 14 digits and is used for outer case coding.
Dumb Reader   Duty Cycle
An RFID reader with that passes data on to other systems or smart readers but cannot itself filter data, execute commands and perform other functions. Compare with an intelligent reader.
The maximum time for which an RFID reader can emit energy. For example, a ten per cent duty cycle means a reader is restricted to transmitting six minutes per hour.