rolls of laminate material

There are many factors that influence barcode quality and performance. Laminate is one of the most misunderstood and elusive, but with the right tools and a clear understanding of the verification report, it is possible to laminate barcodes on labels and packages successfully.

Not all laminates are the same and while the differences are not numerous, they can produce unexpected and confusing results with barcodes. Laminates differ in regards to thickness and surface characteristics.  While thickness is not itself a problem, the laminate material itself can cause distortion of the barcode image as seen by the scanner, and the distortion can in some cases be inconsistent across the height and width of the barcode.

Laminate surfaces are of two basic types—glossy or matte. But there are virtually an infinite variation of both basic types, and reflective performance variations between them.  Highly glossy laminates can obscure the barcode in environments where the ambient lighting is intense, and of course the outbound light from the scanner itself can create a generalized overall reflectance from the barcode: the essential reflective difference of the bars and spaces is obliterated by an undiscriminating high reflectance returning signal. This effect is worsened when the scanner is presented at 90 degrees to the barcode.

Matte laminate can have these and other affects on the barcode. For one, sometimes “matte” isn’t really matte—it is an array of glossy “nubs” or “bumps” on the top surface.  This surface will return a random return reflected signal to the scanner which can be equally confusing and destructive of barcode performance. A truly matte laminate can cause problems of its own, by obscuring the edges between bars and spaces. Scanners decode barcodes by comparing element (bar or space) widths as delineated by the reflective transitions from light to dark.  When those transitions are gradient, barcode performance degrades.

 

Testing laminate and barcode quality with a verifier can help determine barcode performance, but it can be difficult to interpret the affects of the laminate from the verification report. Of course it is essential to use a verifier which complies with the full ISO spec. Verifiers with gun-type scanners cannot test reflectivity or contrast due to the variable angle and distance from the barcode, and reflectivity is what laminates challenge. PDT-based and other verifiers in fixtures where the angle and distance are non-variable can also produce unreliable results due to the uncontrolled influence of ambient light. Problems caused by laminate can be reported as Modulation, Decodability, Decode or even Defects downgrades in the ISO verification report. Sometimes the verifier will report high Average Bar Gain on laminated barcodes—this is especially true when the barcode has a very small X dimension (10 mil or below).

The best way to test for laminate and barcode quality is to isolate it as a variable: test the laminated barcode and test the exact same barcode before lamination. The solution to a very small, laminated sub 10 mil barcode that passes at pre-lamination could be to increase the X dimension.

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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