| 摘要 |
An optical data storage disc comprising a disc-shaped substrate and a centrally-located magnetizable hub. The disc has a central bore configured to receive a drive pin from an optical disc drive. The substrate has a recessed annular portion adjacent its center bore. The hub is provided within the recessed portion of the substrate. The central bore of the disc may be defined by the central bore of the hub alone, so that the diameter of the hub's bore is less than that of the substrate. In the alternative, the central bore of the disc may be defined in part by the inner bores of both the substrate and the hub, in which case those inner bores are of equal diameter. In either case, the thickness of the disc when measured at its inner portion, i.e., in the area of the hub and recessed portion, is equal to the thickness of the substrate at the periphery thereof. By reducing the thickness of the hub area to that of the substrate itself, the number of discs that can be stored together in a fixed space can be increased, thereby increasing the potential storage capacity of an optical disc jukebox or magazine system. |
