A data card having an optical, high resolution erasable or non-erasable laser recording material adhering to it. The strip of laser recording material has a capacity for recording at least 250,000 data bits represented by optically contrasting spots having a dimension of less than 25 microns. The optical...http://www.google.fr/patents/US4680456?utm_source=gb-gplus-shareBrevet US4680456 - Data system employing wallet-size optical card
