Whether you are using 1D barcodes such as GS1-128 or 2D symbols such as Data Matrix codes for UDI compliance marking, UDI barcode verification is essential for assuring barcode quality. Here are some of the most common problems.

Overprinting

Whatever the print method, overprinting or gain is a frequent quality problem:

  • print head temperatures that are too high in thermal, thermal transfer
  • inkjet settings or ink viscosity that are incorrect for the substrate
  • impression settings too high in flexo printing

Visually compare the narrow black and white bars in a 1D barcode, or the dots or squares in a Datamatrix symbol: are they dimensionally equivalent?

Substrate

Metallic or metalized surfaces may not produce the high reflectance values one might logically expect—they often refract rather than reflect light. In these cases, reverse printing the barcode might be best. Patterned or textured surfaces can also be a problem.

Background noise

Printing, graphics or product behind a barcode on a clear pouch can impair the scanability of an otherwise high quality barcode. Eliminate this by printing the barcode over a white patch.

Quiet zone

1D barcodes such as GS1-128 require a minimum leading and training clear area. 2D symbols such as Data Matrix code require a full-surround quiet zone.

Printing a 1D barcode on a small label can be a problem, requiring the barcode to be very accurately and consistently positioned so that neither of the quiet zones is infringed.

 

Excessively long 1D barcodes

Using a 1D barcode to encode a large amount of data can make it challenging to fit onto a label, as described above. Decreasing the X dimension makes it more difficult to print the barcode accurately and to scan it easily. A better solution s to replace the 1D symbol with a Data Matrix code.

Distortion

This can be a problem as printing technology makes it possible to print the barcode on uneven surfaces. 1D barcodes are sensitive to distortion on one axis, but 2D symbols are sensitive on both axes. Avoid direct printing barcodes on bottles or other 3D objects, tapered or curved areas.

Data structure

UDI barcode data structure is very specific. Data fields must be properly prefixed. Some fields are fixed length, and others are variable. This is an area where mistakes are often made. Using a well known, current version of label design software is good insurance against incorrectly structuring a UDI barcode.

Using an ISO compliant barcode verifier that tests for print quality and UDI data structure is an important best-practice.

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3db Barcode Testimonial

Our company (an advanced software company) recently worked with Barcode Test to source a barcode verifier.  Not long ago, we were awarded a contract requiring products to be marked with IUIDs in accordance with MIL-STD-130.  For that standard, marking labels must pass a verification test that evaluates many variables (contrast, size, clarity, syntax, modularity, and more).  After a thorough search, we reduced our options to a select few.

In our search for a verifier, the Axicon line caught our attention.  Barcode Test is our regional reseller for this product.   From the beginning, they were very prompt with their responses.  We ended up having a quick call with John Nachtrieb to go over our needs.  John was extremely easy to work with and provided a lot of great information.  He was very knowledgeable on the matter and was quick to offer up a demo unit (free of charge).

Upon receiving the demo verifier and testing it, a few questions arose.  John joined a call with us and answered all our questions.  Ultimately, the Axicon verifier wasn’t the best fit for us, so we shipped the demo back.  John was completely understanding.  A few weeks later, Barcode Test reached back out with another possible verifier for us to try.  While they didn’t sell that brand, they just wanted to help us find the best option that met our needs. They even offered to send us the unit that they have in-house to see if it worked to our liking. 

Barcode Test is truly a great company to work with.  Their service and willingness to help the customer are far beyond what you typically get from other companies.  They are experts in barcode quality assurance and seem willing to help in any way they can (even if that means not getting a sale and recommending another option that better fits the customer’s needs).  If anyone is in the market for barcode verification/scanning services or products, I would highly recommend giving Barcode Test a call.

Regards,

Production Manager