Decoding Capability
There are two general classes of barcodes: linear (1D) and two-dimensional (2D). They are applied in various kinds of applications, and in some cases are scanned using different types of technology. The main difference between 1D and 2D barcode scanning depend on the layout and quantity of data that can be stored in each, but both can be used efficiently in several automatic identification systems. A further technology is the RFID.
1D Barcode Scanning
Linear barcodes, like the UPC code usually found on consumer goods, use a sequence of variable-width lines and spaces to encode data — what generally people imagine of when they hear “barcode.” 1D barcodes hold just a few dozen characters, and normally get really extended as more data is included. Because operators typically reduce their barcodes to 8-15 characters.
Barcode scanners read 1D barcodes horizontally. 1D laser barcode scanners are the most used scanners, and typically come in a “pistol/gun” style. These scanners do not need to be in contact with the 1D barcode to operate correctly, but usually need to be in a range of 10 to 60 centimetres to scan.
1D barcodes are reliant on database connectivity to be meaningful. If you scan a UPC code, for instance, the characters in the barcode must correlate to an article in a database to be useful. These barcode systems are a requirement for large retailers and can help improve inventory precision and save time.
2D Barcode Scanning
2D barcodes, like Data Matrix, QR Code or PDF417, use patterns of squares, hexagons, dots, and other shapes to encode data. Due on their structure, 2D barcodes can hold more data than 1D codes (up to 2000 characters), although still appearing physically smaller. The data is encoded based on both the vertical and horizontal composition of the pattern, therefore it is read in two dimensions.
A 2D barcode does not just encode alphanumeric info. These codes can also include images, website addresses, voice, and other sorts of binary data. That means you can make use of the info whether you are linked to a database or not. A significant amount of info can travel with an article labelled with a 2D barcode.
2D barcode scanners are normally used to read 2D barcodes, even if some 2D barcodes, like the QR code, can be read with some smartphone apps. 2D barcode scanners can read from over 1 meter away and are available in the popular “pistol/gun” shape, such as cordless, benchtop, and desktop styles. Several 2D barcode scanners are additionally compatible with 1D barcodes, providing the user more flexibility in how they are employed.
RFID Scanning
Radio frequency identification is a common term for technologies that use radio waves to automatically identify people, animals, or objects. There are some ways of identification, but the most popular is to store a serial number that identifies a person an animal or object, and maybe additional info, on a microchip that is connected to an antenna (the chip and the antenna together are called a RFID tag). The antenna allows the microchip to transfer the identification data to a reader. The reader translates the radio waves reflected from the RFID tag into digital info that can later be handed on to computers that can make use of it.
An RFID system involves of a RFID tag, and a reader with an antenna. The reader sends out electromagnetic waves. The tag antenna is tuned to receive these waves. A passive RFID tag takes power from field generated by the reader and uses it to power the microchip’s circuits. The microchip then modulates the waves that the tag sends back to the reader and the reader translates the new waves into digital data.