Barcodes are found everywhere and to the layman they are simply a set of parallel black lines. But once deciphered or read by a barcode reader or scanner, they are found to have a lot of information about the product on which they are stuck. Reading barcodes require scanners or readers.
Barcode Wands
The earliest ones used were referred to as barcode wands. The wands have a small light emitting diode(LED) at their tip and a photo receptor. The receiver gets reflected light from the code and the signal pattern reflection reveals the information and barcode content. The simple process need some expertise that comes with practice since the wand is perpetually switched on and has no trigger button. Held like a writing instrument, the wand has to be moved back and forth over the barcode to be able to read it.
Barcode CCD Scanners
However, Barcode wands have now been replaced by CCD Scanners (Charged Coupled Device). They are extremely reasonable and can outperform wands that are outdated and laser printers that are twice as expensive, if not more. Costing close to a hundred dollars, the CCD scanners are more like advanced wands as they have multiple LEDs and receivers, and can therefore scan the whole code in one single exposition. This also makes them faster and reliable in terms of the information they pick up.
Barcode Laser Scanners
These are some of the latest barcode scanners available in the market today. Equipped with a laser diode at the tip of the scanning head, the beam it uses is projected through a network of mirrors and lenses onto the barcode, and what appears is a string of lights or a single powerful red light. If used on a stand, the laser will automatically catch the information the minute a barcode is detected by it. This helps in increasing the speed of reading and the user's hands remain free. The second type is one with a trigger button
that works more like CCD scanners.
Barcode Imager
Technological advancement has led to the use of area or two-dimensional barcodes, which can store 3000 bytes of information in the regular stamp sized barcode. However, they cannot be read by the usual scanners and need special readers as well. These are called barcode imagers and are somewhat similar to digital cameras. They actually click a picture of the barcode, analyze and decode it, and then transmit the data required to the host computer that needs the information.
Connecting Computers and Barcode Scanners
The Macintosh computers simply need a USB connection to be able to use the scanner. The same holds true for all notebook computers that do not have the advantage of keyboard ports. For general users, barcode scanners therefore need to be connected to PCs with the help of a Y-shaped cable called keyboard wedge. It basically is shaped like the alphabet Y and links the computer, the keyboard and the scanner. The scanner scans the information that passes on to the computer and when required, it can reach he screen by issuing instructions via the keyboard.
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