The challenges faced by the team that created the final Universal Product Code ranged from limited space on grocery packages to myriad types and qualities of printers to a host of stringent technical requirements put forth by the grocery industry. Below are some of these challenges—and one engineer’s perspective on how the team overcame them.
Engineering Was Fun!
In 2008, George Laurer published this book chronicling his time at IBM from the years 1951 through 1987. It contains descriptions and pictures of many IBM products, including an appendix detailing the technical development of the UPC. Laurer's book is available online at lulu.com.
Original symbol design specifications
From the outset, the grocery industry made several things clear to IBM and competing companies searching for a product code solution. The following specifications put forth by the industry were very strict, but they also set key parameters with regard to code and symbol development.
- The symbol area including the human readable characters must be no greater than 1½ sq. in.
- Exactly 10 numeric characters were required.
- The symbol must be printable on present packaging labels with all the printing presses in use at the time.
- The symbol must be capable of being read with a handheld device (a wand).
- The system must be able to read symbols placed on the side of an item as well as the preferred position, which was on the bottom. Thus a depth of field of 6 to 8 inches minimum was implied.
- The symbol must be capable of being read correctly when passed over the scanner at speeds up to 100 in/sec.
- The first pass read rate must be 99.99% or better.
- The undetected error must not exceed 1 in 20,000 reads.
- The system must read the symbol no matter how the symbol is orientated to the scanner.
Republished with permission from George Laurer’s personal memoirs.