METHOD AND APPARATUS FOR CONTROLLING ACCESS TO STORAGE MEDIA

摘要

A method and apparatus for preventing copying of data from optical storage media. A locus (410) on optical storage medium is initially read to produce a signal and is then re-read by a reader to produce a second signal. The signal detected upon re-reading is different from the signal that is detected upon initial sampling. A method and apparatus for controlling access to a storage medium, such as an optically readable medium. Light sensitive or other materials (400) that are adapted to change state and affect reading of a storage medium are used to control access to data that may be stored on optical medium and/or to control use of the medium.