subject: Bar Codes-An Introduction [print this page] Bar Codes-An Introduction Bar Codes-An Introduction
Bar codes are a series of printed line bars, each varying in width, used for entering information in a computer system. The information generally pertains to a particular product for which the code has been created. The bars are spaced and have a specific width that represents the information stored in binary digits and can be decoded by a laser or optical scanner attached to the computer network. These bar codes are found on packages and products ranging from fruit and vegetables to clothes and cosmetics. As soon as the scanner scans the bar code, the required information from the computer appears on the screen.
The barcode system is actually a complete set that includes a computer, software, scanners, printers and labelers that enable thermo transfers or thermo direct printing. Bar code systems can also include mobile terminals that can be used for mobile data acquisition which come with a built-in scanner and reader, a display unit and a keyboard needed to input information. Barcode systems also need to have equipment at the Point-of-sale. These would include high output laser or optical barcode scanners or automatic trigger devices for hands-free scanning.
Barcode Software
Special software is required to create barcodes. The software varies with the operating system used on the computer. It is easy to find software compatible with Microsoft windows, but the best barcode creating software comes with Apple Macintosh computers. The Mac computers are ideally suited for DTP, prepress and the graphics segment. Barcode software has to incorporate barcode symbology, which is the equivalent of a barcode language, make automatic calculations and present multiple output options that can support the most commonly used image formats like PNG, TIFF, JPG and EPS or post-script.
While dedicated barcode generators are needed for the best solutions, cheaper options include barcode fonts, though one cannot expect the same quality of barcodes created by these fonts.
The software needed for dedicated bar code enabled label printing is highly specific and has to be selected according to the application. Thus, there would be different software for print logos, sequential barcodes or barcodes with product images next to them.
Barcode Scanners
The market sells various types of barcode scanners. The first ones ever to be used were barcode wands that were referred to as magic wands. They were equipped with a single light-emitting diode (LED) and a single photo detector, and therefore, the entire barcode had to be swiped for the wand to be able to decipher the code. Now, the most commonly used are laser scanners, which employ a moving laser beam to read the barcode without errors despite its super fast speed. These are expensive and not affordable by small time users. They can opt for the cheaper CCD scanners that use a row of light-emitting diodes and photo detectors.
Barcode Printers
Barcode printers have to be stuck to products and merchandise to be able to identify them. Barcode printers are used to print these on self-adhesive labels. The printers use a system called thermo transfer or thermo direct principle. The thermo direct concept uses a system of applying heat to a specific part of the label to darken those areas, and are sensitive to light. They use the same concept that was applied for the earliest fax machines. These must not be kept for long and used only for short-term, small barcode printing jobs. For instance, they can be used for printing address labels that have to be used for a short while.
Thermo transfer printers work with a heat sensitive ribbon placed between the print head and the label. The application of heat to the ribbon leads to the transfer of ink from the ribbon to the label. The labels thus printed are durable, even though the cost of printing them is more, as it requires ink and ribbon to be used, and replaced over time.
