The number identifies the production date and a serial number for that tire. The plate is then manually placed in the mold, and the tire produced by the patented process. During inspection, workers scan tires before storing them on pallets. These include special requests by the FAA and tires shipped overseas. Although it looks much like a standard hand-held scanner and users a laser to collect data, the bumpy bar code reader operates differently.
Conventional scanners use a laser light source to illuminate the bar code.
The light is reflected back to a light sensor that distinguishes the differences in contrast between the bar code's black and white bars. The scanner is equally able to read bar codes molded in rubber, stamped in metal or embossed in any other material. When the trigger on the reader is pulled, a laser beam is projected across the width of the bumpy code. The light is immediately reflected back to the reader and collected by the CCD array. Compared to the original laser beam, the reflected light is captured at slight angles representative of the differences in height between the bumpy bar code bars and spaces.