METHODS AND APPARATUS FOR PHYSICALLY PATTERNING NONOPERATIONAL STRUCTURES OF AN OPTICAL DISC

摘要

Methods and apparatus for physically patterning readable non-operational structures (30, 32, 34) on an optical disc (10) are presented. In one embodiment, the non-operational structures are magnetic beads (60) and the method comprises applying external magnetic fields (44) to the optical disc (10). In another embodimen t, the nonoperational structures have net-electric charge.