摘要 |
An optical information storage card (10) having a rectangular format, said card comprising: a substrate having, on at least one side thereof, surface relief formations forming an optically machine readable information surface (A); and, a protection layer being in overlying juxtaposed relationship to said information surface; said substrate and said protection layer being transmissive to a selected range of electromagnetic radiation usable for optically reading said information surface; said information surface having a generally spiral and/or concentric format whereby said information surface can be read as said card is rotated about at least one axis. |