二维码基础知识精要.pdf

Datalogic Automation USS-TSS Unattended Scanning Systems Technical Support & Services Barcodes & 2D Codes Place -DD/MM/YYYY -Session XX 2D Codes Fundamentals Datalogic Automation Module’s Contents ?2D Codes Introduction ?Stacked Symbologies ?PDF417 and Micro PDF417 ?Matrix Symbologies ?Data Matrix code ?QR Code ?Aztec Code ?Maxicode ?GS1 DataBar Symbologies ?Composite Symbologies ?Postal Codes ?Australia Post ?Sectors and Applications ?Glossary Datalogic Automation Why Do We Need 2D Symbols? We need -using less space-more information in time and at the point of decision: ?2D labels on blood transfusion bag cross-checked against 2D symbols on patient’s wrist band. ?100 character square inch Maxicode drives a package through a work. ?Information encoded in a 2D symbol on a product available at a POS. ?PDF417 symbology inside of an automobile door frame. ?Data Matrix ECC200 printed on puter chip: traceability and identification data. “on the spot and on the fly” Datalogic Automation Linear (1D) Codes symbologies ?Information only on X-axis (one single row) ?Low capacity, typically 15 to 50 character carrying capability, depending upon symbology and the symbol form ?Vertically Redundancy: same information repeated in Y-axis tolerates printing dropout ?Made up of one series of bars and spaces of different width (not only binary modulation) ?Machine readable “licence plate”: key into a data base containing detailed information BUT ... … this is not “on the spot and on the fly” Datalogic Automation 2D Codes Symbologies ?Two-dimensional code: information along the height (X-axis) as well as the length (Y-axis) of the symbol ?No vertically redundancy ?2D Codes tolerates printing dropouts because of ?Error Correction Capability (ECC) ?Increase the effective density of the encoding: more data in a smaller space ?Portable database (rather than just a database key): plete data files in an optically readable symbol and so …?… extend the potential market for AUTO-ID ?T