[is] 3,700,862  Oct. 24,1972
INDICIA SYSTEM FOR CREDIT CARDS AND THE LIKE
Inventors: Richard K. Snook, Bridgeton; Rodney W. Stout, Webster Groves, both of Mo.
2,640,647 6/1953 Rand.Jr 235/61.12 M
2,952,008 9/1960 Mitchell et al 235/61.12 M
3,211,470 10/1965 Wilson 235/61.12 M
3,453,598 7/1969 Schweizer 235/61.7 B
3,512,130 5/1970 Hulett 235/61.7 B
3,531,627 9/1970 Ham 235/61.12 M
Primary Examiner—Daryl W. Cook
Attorney—Robert J. Schaap
A system for imprinting indicia in binary form on credit cards and similar plastic members which includes a printing mechanism for printing two tracks of clock or synchronizing pulses and two tracks of data pulses on spaced portions of a credit card. One data track is recorded in such manner that it is a complement of the other data track in order to provide at least 100 percent redundancy. A reading system is also disclosed and which involves a gating structure for determining true states of the complementary data in each of the data tracks at clock pulse time. In addition, the reading system compensates for a condition of skew in the printing or in the reading of the card.
11 Claims, 21 Drawing Figures