• Call Cognex Sales: 855-4-COGNEX (855-426-4639)
  • Contact us
  • 2-D Matrix Codes

    2-D codes contain information both horizontally and vertically, allowing them to store much more data. For example, a single 2-D code can hold up to 3,116 numeric characters or 2,335 alphanumeric characters, compared to the 39 characters that Code 39 can hold.

    Unlike 1-D barcodes, all 2-D codes have built-in error correction, similar to the check digits in some 1-D codes, which effectively eliminates misreads. Within a single DataMatrix code, the data is typically encoded three times, which significantly increases the chances the code will be read correctly. Vision-enabled barcode readers would have to scan 10.5 million codes to misread a single 2-D barcode; laser scanners, which cannot read 2-D codes, cannot claim this level of accuracy.

    While 1-D codes have quiet zones and guard patterns to identify where the code starts and stops, a 2-D code has a quiet zone, a finder pattern, and a clocking pattern. The finder pattern is the L-shaped pattern located around the outside edge of two sides of the 2-D code. This is used to ensure proper orientation during decoding. Opposite the finder pattern is the clocking pattern, a series of alternating black and white modules (or cells) that defines how big a single cell is and the size of the code (number of rows and columns) for decoding. The quiet zone is similar to that of 1-D barcodes; for 2-D codes, however, it must surround the entire code.

    2-D Barcode Symbologies

    Common 2-D codes include: DataMatrix, utilized by aerospace, defense, printed media and the U.S. Postal Service; MaxiCode, a dot-based code that is used in logistics applications; QR codes, used in automotive and commercial marketing applications; and Aztec codes, used by ticket agencies and rental car companies.

    Let's Talk Symbology - A Guide to Decoding Barcodes

  • SYMBOLOGY GUIDE

    Get answers to the most commonly-asked questions about barcode symbologies.

    DataMan Barcode
    Readers Guide

    Learn about the entire family of DataMan barcode readers.

    INTRODUCTION TO INDUSTRIAL ID BARCODE READING

    Learn how to maximize read rates, increase throughput, decrease costly rework.