Patent ID: 7564765
Filing Date: 2009-07-21
Classification: G11B

Abstract:
1. An optical pickup device condensing a laser beam toward a data recording face of an optical disk, recording data in the optical disk, and reproducing data from the optical disk, the optical pickup device comprising: a light source configured to emit a laser beam toward the optical disk; a light-receiving sensor that has a main tracking light detection portion and a sub-tracking light detection portion, the main tracking light receiving, of light reflected by the data recording face of the optical disk, light that is used for tracking control of the optical pickup device, and the sub-tracking light detection portion receiving light that is used as auxiliary light for tracking control; and a hologram that includes a tracking area having a main tracking area and a sub-tracking area, the main tracking area separating a light flux that impinges on the main tracking light detection portion from the light reflected by the data recording face of the optical disk, the sub-tracking area separating a light flux that impinges on the sub-tracking light detection portion from the light reflected by the data recording face, the main tracking area and the sub-tracking area being defined by a tangential division line extended in a tangential direction, the tangential direction being parallel to a line tangential to the circumference at a light condensing position of the optical disk, wherein the tracking area of the hologram is defined as the main tracking area and the sub-tracking area by a radical division line, the radical division line being extended in a radial direction that parallels a radius of the optical disk at the light condensing position, and wherein the main tracking area and the sub-tracking area have the same width in the radial direction.