Patent ID: 8335140
Filing Date: 2012-12-18
Classification: G11B

Abstract:
1. An optical disc drive configured to emit a laser beam to record or reproduce data on a multilayer optical disc, the multilayer optical disc having a plurality of recording layers, the optical disc drive comprising: an optical pickup configured to emit the laser beam to the multilayer optical disc. a stepping motor configured to move the optical pickup in a radial direction of the disc; a signal processing unit configured to process a reproduced signal from the multilayer optical disc; and a controller configured to identify the recording layers of the multilayer optical disc and configured to control operations of the overall optical disc drive; wherein the multilayer optical disc includes, in a layer identification region, a layer specific region having a specific pattern for layer identification; wherein when the recording layer of the multilayer optical disc is identified, the controller is configured to cause the optical pickup to start focus servo control on the current recording layer; wherein the controller is configured to cause the stepping motor to move the optical pickup to the layer identification region and is configured to detect the layer specific region having the specific pattern from the layer identification region without tracking servo control; wherein the controller is configured to identify a current layer based on a radial position of the layer specific region.