Magneto-optical record carrier for disc or card

摘要

The record carrier has a transparent substrate (1) coated in sequence with a transparent dielectric layer (2). There is a readout magnetic film (3) layer, a non-magnetic intermediate layer (4), two further vertically magnetised layers (5,6) and a protective coating (7). The readout film is magnetised in its own plane at room temperature, and vertically at higher temperatures. The final magnetic layer (6) has a lower room-temperature coercive field strength and a higher Curie temperature, than its predecessor (5).