How Do Barcodes Work?

How do barcodes work?
Barcodes work by having combinations of black bars or dots and spaces. Each barcode type has its own unique language or format. The most common bar code type is one-dimensional bar codes (1-D) which are a series of black bars. When a barcode is swiped or scanned the reader directs some kind of light toward the black bars and spaces and then measures the reflection of light back to the reader. When light is directed at white spaces it reflects the light while light is absorbed by black bars. In this way the reader can determine if it is passing over a black bar (no reflection) or a white space (reflection). The reader can also sense the width of the bars or the spaces.

With the basic concept of being able to read bars and spaces and their respective widths, formats have been constructed that assign a character (example 1-9, A-Z, etc) to a unique combination of bars and spaces.

The following are two examples of how a common 1-D format type, called Code 39 uses this basic principal of unique sequences of bars and spaces to present a single character:

By stringing these unique sequences together you can form multiple characters or numbers. For example "A0" would be as follows:
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This simple set of concepts is used to create dozens of different bar codes types for multiple applications.

About ColorID, LLC
Every year, ColorID assists more than 1000 colleges and universities and their project managers personally oversee 700 custom projects each year, including many small and large recarding projects.  ColorID offers best-in-class products and solutions, including:  contactless, smart and financial cards from every major manufacturer, multiple ID printer platforms; transaction and point-of-sale software and hardware, a variety of handheld devices for identification and tracking applications and biometrics solutions, including fingerprint and iris readers. The company’s manufacturing partners include: Iris ID, HID, Fargo, Datacard, CardSmith, Gemalto, Zebra, NiSCA, Evolis, Allegion, Aptiq, Magicard, Brady People ID, Integrated Biometrics, Oberthur, NBS, Vision Database Systems and many others.

Contact ColorID at 704-987-2238 or toll free in Canada and the US at 888-682-6567. Visit ColorID on the web at: www.colorid.com or email ColorID at [email protected].

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