A method for making an optical memory storage medium which has a transparent substrate with void cells of empty spaces and ablative material on the cell walls is disclosed. In one example, a base plate is coated with a masking layer. Pits are formed on the plate by mechanically stamping the masking layer...http://www.google.de/patents/US4740266?utm_source=gb-gplus-sharePatent US4740266 - Method of making memory devices
