|
Wired CCD Barcode Scanners
|
 |
|
|
|
These devices use a series of Light Emitting Diodes to generate a "red glow" light source, a lens and a photo conductor to decode a barcode image into the data that is contained in the barcode. Since the red glow is not very intense and the technology relies on emitted ambient light, the operator will need to place the scanner fairly close to the barcode (about 2-3cm).
|
|
|
|
|
|
|
Wired Laser Barcode Scanners
|
|
|
|
|
These devices use a "pin-point" laser light source and a reciprocating mirror to scan the laser beam back and forth across the barcode. They use reflected light to decode a barcode image into the data that is contained in the barcode. Since the laser is a fairly intense light source, the operator does not need to place the scanner close to the barcode and can scan barcodes that are about 10-30cm away from the scanner. Some industrial laser scanners can read a barcode that is a very long distance away (2 metres).
|
|
|
|
|
|
|
Wired Linear Imager Barcode Scanners
|
|
|
|
|
These devices use an imager similar to that used in a digital camera to "take an image" of the barcode and then decode the data in the barcode. Linear Imager scanners tend to be more aggressive in scanning barcodes than are linear laser barcode scanners because the imager acts more like an omni-directional laser barcode scanner.
|
|
|
|
|
|
|
Wired 2D-barcode Barcode Scanners
|
|
|
|
|
These devices may use a CCD or a small video camera to capture an image of a barcode. The reader then uses sophisticated digital image processing techniques to decode the barcode. They can read 2-dimensional (2D) barcodes as well as linear barcodes. Some 2D barcode symbologies include PDF417, DataMatrix and QR Code. The less expensive 2D-barcode scanners can only read PDF417 codes.
|
|
|
|
