Patent ID: 8385178
Filing Date: 2013-02-26
Classification: G11B

Abstract:
1. A method of focusing a beam to a holographic disk, the method comprising: determining a target data position on a target data layer in the holographic disk; actuating one or more optical components using a first component of a multi-stage actuator, wherein the first component is configured to actuate the one or more optical components to change a focus depth of a beam in a displacement range corresponding to a thickness of data layers in the holographic disk, such that the beam is impinged on the target data layer; and actuating one or more optical components using a second component of the multi-stage actuator, wherein the second component is configured to actuate the one or more optical components to focus the beam on the target data position, and wherein actuating the one or more optical components using the second component comprises actuating the one or more optical components in a tilting motion.