A data card or display device has a display region of non-volatile, display medium, which is re-writable with humanly legible characters and an indexing track composed of a machine readable, coded pattern of indicia is marked along a datum edge thereof. A read-write terminal has a read head aligned with...http://www.google.ca/patents/US5988513?utm_source=gb-gplus-sharePatent US5988513 - Re-writable display device and system including a carrier having humanly legible characters and an indexing track
