The technology used to read barcodes is relatively simple, but there is little information available for the novice. This is intended to be an introduction to the scanning, processing and presentation of barcode information.
A scanner is a device that converts the image of a barcode into electrical pulses. There are four basic ways of doing this: contact wands, active non-contact (AKA laser scanners), and passive non-contact, which can be cameras or linear CCDs (charge coupled devices). All of these devices have similar outputs, strings of electrical pulses that mimic the white/dark and width of the bars. With the exception of cameras, a scanner will always include a light source, either LED or laser.
Wands are the simplest, but have the most limitations. A wand has a light source, focusing lens and a light detector. It has no moving parts, which makes it the most rugged of scanners, but … Read More