Tuesday, April 24, 2012

Barcode – So how did it all started and how to use it (EAN-13 ...

In 1949, Joseph Woodland was wrestling with the concept of automatically capturing information about an item. He believed that the dots and dashes of Morse code would to be a good place to start. He could not figure out how to use those morse code patterns to solve the problem. Then, one day as he relaxed at the beach, he drew dots and dashes in the sand. As his fingers elongated the dashes he looked at the result and released this was the answer.

Three years later Joseph Woodland and his partner received a patent on what began as lines in the sand, and the linear bar code was born. It took many years for the concept to become a commercial reality. Although the barcode concept was used in a few areas prior to 1974 the first appearance in the retail sector was in 1974.

On June 26,1974, at a Marsh supermarket in Troy, Ohio, a single pack of Wrigleys chewing gum became the first retail product sold with the help of a barcode scanner. This barcode scanner looked nothing like today’s small and sleak models but it worked. Decades of schemes and billions of dollars in investment now became a practical reality. The use of scanners grew slowly at first. A minimum of 85 percent of all products would have to carry the codes before the system could pay for itself. When the level of products reached that level, in the late 1970s, sales of the systems started to take off. In 1978 less than one percent of grocery stores in the USA had Barcode scanners. By mid-1981 the figure was 10 percent, three years later it was 33 percent, and today most retail shops have barcode scanners.

What is an EAN barcode?

The EAN barcode actually stands for European Article Number and a properly registered number is unique throughout the world. It is this uniqueness that makes this barcode type attractive for large retailers buying goods from many suppliers. If you are a manufacturer/distributor then you get a sequence of EAN barcode numbers. The first nine digits, the EAN-UCC company prefix, are allocated to the company. Prefixes first two numbers shows companys country location. All countries have own prefixes. The next three digits are the non-significant item reference number. The simplest way to allocate item references is sequentially, i.e. 000, 001, 002, 003 etc. Always number each item to the lowest level of identification. For example: size, colour, model, finish, type, style. This ensures that each item has a unique number. The last digit is always the check digit, which is calculated by a mathematical formula to ensure that the whole number is correct.

EAN-13 Symbology Specifications

Bar Height
Once the magnification of the bar code symbol has been determined, for EAN/UPC Bar Code Symbols it is important to ensure that the height remains in proportion to the magnification, and does not drop below the minimum specified. Please note that truncation (height reduction) on any symbol will reduce scanning reliability, and where space permits the full height should always be printed.

Magnification
The specified magnification range for an EAN-13 Bar Code Symbol being scanned at retail POS 80% – 200% (X-dimension 0.26mm – 0.66mm). An allowable minimum magnification of 75% (X-dimension 0.25mm) is applicable only to on demand (e.g. thermal) print processes. In this case, the bar height should never be truncated below the minimum required height for an 80% magnification bar code symbol. Where an item may also be scanned in a General Distribution Scanning environment (automated scanning), the allowable magnification range is 150% to 200% (X-dimension 0.50mm – 0.66mm).

Quiet Zones (Light Margins)
The Quiet Zones (Light Margin) of the bar code symbol are the solid, light areas before the first bar and after the last bar. These areas are extremely important as they allow the scanner to recognise the beginning and end of the bar code symbol. Any obstruction or reduction in the Quiet Zones will most likely result in scanning difficulties. The minimum size required for the Quiet Zones depends on the magnification of the bar code symbol. It is recommended to allow slightly more than the minimum required Quiet Zones to allow for any possible ink spread or plate registration issues.

Colours
The colours and type of ink you choose for your bar code symbols is very important. As a scanner reads a bar code symbol using an infrared light source it sees the symbol differently to the human eye. As a result, some colour combinations and ink types are unsuitable for scanning because they do not provide sufficient contrast between the dark bars and the light background, or they provide a much too high reflectance value. The most suitable and reliable colour combination is black bars on a white background. However, as a general rule, the background of the bar code symbol can be a light, warm colour that does not contain any black (such as yellow or light orange), and the bar colour can be a dark, cool colour that has no, or low, red content (such as dark blue or dark green). It is also a recommendation to avoid high gloss inks as this can cause problems with the reflectance values.

Human Readable Interpretation
The Human Readable Interpretation should be printed beneath the bar code symbol. The recommended typeface for the Human Readable Interpretation is OCR-B at a height of 2.75mm at nominal size (100% magnification, X-dimension 0.33mm). This typeface is a recommendation only and alternative type fonts and character sizes are acceptable provided the digits are clearly legible.

Text source: www.gs1au.org

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