Abstract: Provided herein, is an apparatus that includes a fluid dynamic bearing, a hub, and an induction housing. The fluid dynamic bearing is defined by a stationary component and a rotatable component. The hub is configured to rotate relative to the stationary component. A current is induced within the induction housing resulting from the relative rotation. The induced current creates a repulsive force between the stationary component and the hub.
Abstract: A double-sided optical disc, such as a DVD-18 disc, is formed with data tracks on each layer. The tracks on one side are oriented along one spiral while the tracks on the other side are oriented along a second spiral, the two spirals being oriented in opposite directions as viewed from the respective sides. A player with two laser read heads is provided for reading the disc. Each laser read head is disposed adjacent to a respective disc side. The data is read from the two sides, either in sequence from one side and then the other, simultaneously, or in some alternating fashion.
Type:
Grant
Filed:
November 18, 2003
Date of Patent:
December 19, 2006
Assignee:
Warner Bros. Home Entertainment Inc.
Inventors:
Christopher J. Cookson, Lewis S. Ostrover