Verifier Styleįor 2D codes on products that vary in shape and size, a verifier with the ability to adjust the camera height to the proper focus is useful. A verifier must be able to accommodate a code’s minimum x-dimension otherwise, the camera resolution will not be able to properly capture the image needed to perform the verification. How small is the smallest module (space or cell) in your code? This measurement is the minimum x-dimension. How big is the largest barcode being printed? A barcode verifier needs a field of view that is large enough to fit a 2-D barcode and still leave enough space to meet the quiet zone requirements specific to that symbol type. For example, 2-D codes printed on a reflective surface work best with a 90-degree lighting angle. For 2-D barcodes that are directly marked, a verifier with 30- and 90-degree lighting options in addition to 45-degree will be able to properly illuminate a variety of different background surfaces. 45-degree lighting is stipulated in all of the ISO barcode specifications for verifying barcodes printed on a flat surface. All camera-based verifiers must include 45-degree lighting in order to grade these regular printed codes. The 45-degree angle is the most common lighting angle because it is the standard for non-DPM (paper, or regular label) verification. Download: Introduction to Barcode Verification Whitepaper.To successfully verify a 2-D code, a barcode verifier must accommodate specific field of view, minimum x-dimension, lighting angle, format, and software requirements. As with all barcode verification, 2-D codes should be tested at the time they are printed. A barcode verifier built specifically for verifying 2-D codes and which uses a camera rather than a laser to capture an image of the code is necessary. It is important to remember that one cannot verify with software alone. Typically, 2-D codes are verified against GS1 or ISO standards such as ISO 15415 or ISO TR 29158 (AIM DPM). With a higher amount of variable data, 2-D codes are more challenging to verify and exhibit higher failure rates. If you use a fine screen to deliver more ink to the substrate, be sure there are no voids in the print caused by the screen not adequately filling in.2-D barcodes typically hold dozens of characters and more information than a 1-D barcode.If you use multiple layers of ink to increase the background opacity, each layer should be printed as a solid colour.However, if the symbol background is printed beneath the bars, the background should be printed as solid line colours. In many cases the symbol background is not printed and the colour of the packaging substrate is used as barcode background.Given the fact that most barcode scanners use a red-light source, you can quickly see why these colours may be suitable for backgrounds but should be avoided for bars. This is also true of similar colours such as orange, pink, peach, and light yellows. If you have ever been in a darkroom with red lighting and tried to read red copy, you know it can virtually disappear. In addition to light backgrounds, “reddish” colours may also be used.GS1 barcodes require light backgrounds for the Quiet Zones (area free of printing around the barcode) and spaces (e.g., white).
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