Miniature optical disk for data storage

Abstract

An optical medium including a substrate and information content portions is provided. The optical medium is preferably a first-surface medium in which a read light beam during a read operation impinges first on the information content portions of the medium before it impinges on the substrate. The information content portions can include both read-only and writeable areas. The information content portions containing both read- only and writeable areas can be made from the same material or composition. The optical medium diameter is no greater than about 40 mm. The thickness of the optical medium is no greater than about 0.6 mm. When joining a hub assembly to the medium, a portion of the medium, such as a track, is utilized for alignment purposes. The ratio of the total height of the hub assembly to the thickness of the optical storage medium is at least about 1.5. The hub assembly can include a magnetic coupling for use in connecting the optical medium to an optical drive spindle.

Dependencies are inferred from the claim text.