MANUALLY CODEABLE CARDS FOR CARD READERS

摘要

A kind of manually codeable card for card readers composed of an upper and a lower sheet of transparent material glued together, the lower sheet printed with black ink all over except a plurality of transparent circles which can be sticked on to become opaque with black circles from a paper with transposable black circles or round opaque stickers. The coded number of the card is represented by the different combination of transparent and opaque circles.