Laser Marking

UID Solutions - Why Use the 2-Dimensional Data Matrix?

Choosing the right two dimensional code for your application requires decisions on: 

• Physical space availability
• Contrast issues
• Printing technology (laser marking, dot peening, etc.)
• Scanner/Reader requirements
• Cost considerations
• Mil-Std-130 compliance

All-Marks provides equipment to print Mil-Std-130M compliant 2D codes. In addition, we can provide integrated 2D code readers from such major suppliers as Siemens, Ci-Matrix, Microscan, DVT, Cognex and SICK as well as recommend the optimum hand held readers for your application.

Background Information

Linear or one-dimensional bar codes are limited in the amount of information that can be contained within the code. Other technologies, such as magnetic stripe or RF tags can hold more information but are more expensive to implement. In an effort to develop bar code symbologies that would hold more information, stacked codes were developed.

Stacked codes are linear bar codes printed one above the other to form a single symbol. These codes could be read by conventional reading equipment, such as laser or CCD handheld scanners. Some examples of stacked codes are Code 49, Code 16K and PDF417.

To increase the density of information even further, matrix codes were developed. Matrix codes encode information using fixed width light and dark cells and also utilize sophisticated error/erasure correction algorithms to compensate for lost or missing data, extraneous marks, or code damage. There is usually some standard locator pattern, that is part of the image, to assure correct orientation when decoding the symbol. This means that print quality and contrast are much less critical than with 1-D bar codes or stacked bar codes. In fact, matrix codes can be applied directly to silicon wafers, PCBs, automotive components, or other applications where paper labels are inappropriate.

Since they are not really "barcodes" anymore, conventional scanners can no longer read these codes. They are normally read by scanners using two-dimensional CCD devices that can capture an image of the entire symbol. Examples of matrix codes include Data Matrix, Maxicode, Aztec Code, PDF 417, QR Code and Snowflake.

The amount of information contained within each individual two-dimensional mark allows independent database with complete freedom of movement, traveling together with a person or an item, object, package form, document, card or label. It does what wired networks can't: allows you to immediately access your data regardless of location. In addition, encryption is available as an option when additional security is required. Moreover, because both matrix and stacked codes are machine-readable, it eliminates time consuming and error prone manual data entry.

 

Movement from Linear Bar Codes to 2D Codes

The shift from 1D to 2D coding is being driven by the fact that the traditional linear bar code is incapable of meeting industry's desire to encode larger blocks of data, such as expiration dates, lot/batch numbers, serial numbers, product codes and traceability codes. Traditionally, the bar code industry has reacted to this demand by continuously shrinking the size of the linear codes and developing denser formats. However, this is constrained by the printing technology available to produce them. Additionally, numerous data integrity tests have been conducted to evaluate the robustness of both matrix and stacked codes. Results of these tests corroborate the fact that the newer symbologies that include error correction are extremely robust when compared with traditional 1D codes, when error rates shown to be less than one in 10,000,000 characters.

All-Marks has the capability of upgrading your present marking process to include 2D code marking and reading in compliance with Mil-Std-130M. Marking systems offered by All-Marks provide the capability to print traditional 1D bar codes as well as 2D codes (Which are commonly used for UID Labels). Our systems include laser marking and dot peening technologies for Direct Product Marking (DPM), thereby creating a permanent and robust mark without the expense and hassle of labels. All 2D codes require a 2D code reader for verification and/or validation which are additionally available through All-Marks.

 

Data Matrix Symbol Construction

Any Data Matrix symbol is comprised of the following major components:

• The L-shaped solid border
• The broken border on the opposite corner
• The data storage area inside the symbol and
• The quite zone outside of the symbol