A barcode scanner (reader) is an electronic device which may read and export printed barcodes to a computer. In the case of a flat scanner, the device consists of a light source, a lens, and a light sensor which translates the optical impulses to the electric impulses. Besides, almost all the barcode scanners include decoding circuits which analyse the pixel data of visual barcodes provided by a scanner and transmitting a content of the barcode to an output scanner port.
The task of readers is to quickly and correctly read a barcode and transmit its content to a host. An ordinary computer, cash machine or other devices supporting any of the standard industrial interfaces. The connection of a scanner to a host can be realized with a cable or wirelessly - usually Bluetooth technology.
In terms of the scanning pattern we can divide scanners to laser and digital. Laser scanners use a reading technology of one or more rays that is emitted by laser diodes and are able to read barcodes even from longer distances. The principle of digital scanners is the same as with digital cameras: the code is snapped and the picture is then decoded by an integrated decoder. The advantage is multidirectional reading of 1D and of all 2D codes.