Patent ID: 6249498
Filing Date: 2001-06-19
Classification: G11B

Abstract:
A tilt detecting method in a recorded information reproducing apparatus, in which a tilt occurring between a recording disk on which information has been recorded and a pickup for photoelectrically converting reflection light when a reading beam is irradiated onto a recording track formed on said recording disk and obtaining a read signal is detected, comprising the steps of:setting a reading position of said pickup for a center recording track among three adjacent recording tracks to a reference;detecting a crosstalk amount, as a first crosstalk from each of first positions on a recording track that is adjacent to said center recording track on the disk's inner rim side, said first positions being located forward and rearward along the direction of the recording track relative to said reading position by a predetermined distance in a reading direction;detecting a crosstalk amount, as a second crosstalk, from each of second positions on a recording track that is adjacent to said center recording track on the disk's outer rim side, said second positions being located forward and rearward along the direction of the recording track relative to said reading position by a predetermined distance in the reading direction; anddetecting the tilt occurring between said recording disk and said pickup on the basis of a balance between said first and second crosstalks,wherein said first positions are set at positions of a side lobe of said reading beam which is irradiated to the recording track that is adjacent to said center recording track on the disk's inner rim side when a tilt occurs between said recording disk and said pickup, and said second positions are set at positions of a side lobe of said reading beam which is irradiated to the recording track that is adjacent to said center recording track on the disk's outer rim side when a tilt occurs between said recording disk and said pickup.