How Barcode Became First Stop To The Internet of Things
We see barcodes all over the place in retail to courier boxes from cereal boxes to prescription labels and from envelopes to electronics – it seems like barcodes are everywhere.
When Alan Haberman pioneered the use of a UPC barcode in his grocery business he kicked off not only a revolution in inventory management and the supply chain but also made a step towards the metadata overlays of physical items and information we now call the internet of things.
But what do those black lines and dots mean? Much like the URL of a web site Barcodes themselves do not contain descriptive information but a number plate that links to a reference which is looked up in a database that then contains the data required.
There are two major barcode types one and two dimensional. One dimensional (1D) originated from the original barcode concept and are even today are the most commonly used. Codes are made of a series of vertical lines/bars and spaces of varying widths. The X dimension being the width of the narrowest element. These bar and space combinations are strung together to represent different characters.
Two dimensional codes use a series of dots, blocks and other geometric shapes into a square or rectangular pattern. 2D barcodes are generally able to contain much more information than 1D. Where a 1D barcode code contains a small number of alpha numeric characters digits, a 2D barcode such as a QR code may contain thousands of alpha-numeric characters.
In each category there are many different designs that have been designed over the years for various applications. The seminal read in this area is The Bar Code Book by Roger Palmer. It was last revised in 2007 before Rogers retirement but is still an excellent read. There are also many sites on the internet to barcode and its uses.
Barcodes have become so widespread that for many users their use has become a compliance issue. GS1 develops and maintains standards for supply and demand chains across multiple sectors. They are also good at explaining the impact of barcodes.
In either case codes need to be machine read by something. Traditionally this was through a laser based scanner. Shipments of this sort of scanner have declined in recent years as imaging based technologies have grown more popular.
For ad hoc use you can download an app for your smartphone that will read both 1D and 2D barcodes through the camera. If your application is such that you need to scan barcodes in volume a device with a specific barcode scanner/imager and perhaps with a trigger handle will be more ergonomic for the user.
Back To Basics – Popular Barcode Types
EAN 13 similar to but not quite the same as Universal Product Code (UPC) which are both standardised for retail and food sales. It is the code seen on virtually every product you buy in the retail supply chain. It uses 12 digits numeric only sequence represented by bars and spaces of four different widths. UPC is a subset of the International Article Number system which includes an additional check digit.
Code 39 was invented by Intermec Technoloies in 1966 and is still used primarily forinventory and manufacturing applications. Each character comprises nine bars and spaces, of which three bars or spaces are wide and the remaining nine are narrow. Code 39 supports 43 characters: 0-9 A-Z and several special characters. There is no predefined limit to the length of code 39 barcodes which may make it unsuitable for some applications where the code length would be too long.
The QR code was invented by Toyota for the automotive parts industry. They can be seen in use extensively in advertising entertainment and promotional applications. Helped in great part by Smartphones with built in cameras. QR codes can contain alphanumeric and bit/binary as well as Kanji.
Decades on from Alan Haberman the scanning of barcodes at a supermarket has become commonplace. The legacy of that first depolyment is in having more scannable items in the Internet of Things Ecosystem. Recognising the different types and uses of these barcodes will help you in identifying not only which style will work for your project but also which method of scanning will be most suited to support them.
Whats next for barcode? maybe the future is a scanner on everyone’s Google glass ?