A barcode can be termed as a printed horizontal strip of vertical bars with different widths that represent decimal digits and are used for identification of commercial products or parts. The barcodes are printed on labels which are termed as barcode labels. The data on barcodes is read by a device called a barcode reader or a barcode scanner. The read information is then stored on a system. This is used to track the items and record the information. Barcodes have various symbologies and based on them the scanners used also change.
A barcode scanner has a light source, a lens and a light sensor. The optical impulses are translated into electric ones. Some barcode readers have a decoder that analyzes the image data which is provided by the sensor. The decoder then sends the content to the output port of scanner.
Barcode scanners are available in different types of technologies. Based on the type of technology used, these can be of various types. These include laser scanners, CCD readers, pen-type scanners, camera based scanners and cell phone cameras. Certain scanners are available that are referred as housing type of scanners. These include stationary scanner, handheld scanner, fixed position scanner, PDA scanner, automatic reader and a cordless scanner.
The connection systems for the reader is of various types. Early serial interfaces are present which have an electrically simple means of connection and the software which makes it simple. RS232 is the universally common early interface used. Using keyboard wedges has become popular as it reduces the complexity of the associated software. The keyboard hardware is plugged between the PC and the normal keyboard. This provides characters from the scanner which are similar to those that are typed at the keyboard. Later, USB connectors have been used. Most common USB interface used include HID and CDC types. The most recent application of wireless technology has become prominent these days.