Patent ID: 6317403
Filing Date: 2001-11-13
Classification: G11B

Abstract:
An optical disc apparatus for reproducing a dual layer Digital Versatile Disc (DVD) which has two recording layers including layer 0 and layer 1 reproducible from one side of the DVD, wherein each layer has a plurality of sectors, said apparatus comprising:an optical pickup having a laser source from which an optical beam emanates;an objective lens which concentrates the optical beam on a recording layer;an actuator which moves the objective lens in the direction of the thickness of the DVD, wherein a focal point of the objective lens is focused on one layer of said two recording layers;a slider which moves the optical pickup in the radial direction of the DVD;a controllerwhich obtains a present layer information of a sector recording layer being produced from light reflected from the DVD;which confirms a target layer information of a target recording layer of a target information;which judges whether said present layer information is the same as the target layer information; andwhich outputs a control signal to the actuator when it is judged that the present layer information is layer 0 and the target layer information is layer 1; andwhich outputs a control signal to the slider,wherein said actuator moves the objective lens in the direction of the thickness of the DVD in response to the control signal to the actuator until the focal point of the objective lens is focused on layer 1, andwherein said slider moves the optical pickup target position in response to the control signal to the slider after the focal point of the objective lens is moved to layer 1.