“Their research began in 1948 after Mr Silver, a graduate student at the Drexel Institute of Technology in Philadelphia, overheard a local food chain boss asking one of the institute's deans to design a system for reading product data automatically.
Mr Silver and Mr Woodland, a fellow graduate student and teacher at Drexel, first tried using patterns of ink that glowed under ultraviolet light, but it proved too expensive and unreliable.
Mr Woodland then came up with the linear bar code, and later replaced the lines with circles so that they could be scanned from any angle. The pair patented their “bull’s eye” design the next year.
The bar code was first trialled in 1966, and in 1970 the familiar Universal Product Code (UPC) design, still used around the world, was agreed on as an industry standard.
The first item to be scanned using UPC was a packet of Wrigley’s chewing gum at a supermarket in Troy, Ohio, in June 1974.
Neither inventor made a fortune on the idea because they sold the patent in 1952 for a moderate sum before it was commercialised.
Mr Silver never even witnessed the bar code’s success, having died in a car crash in 1962.”
Source: Daily Telegraph