Method for detecting servo error, apparatus therefor, disk which maintains quality of servo error signal, method of controlling servo of disk recording/reproducing apparatus, method of detecting tracking error, and method of detecting tilt error

A method of detecting a tracking error of an apparatus for reproducing data from an optical disk having a first reference signal and a second reference signal which are recorded to deviate from a center of a track in opposite directions and which have the same pattern, the method comprising:

• determining a first level Ivfo1 of the first reference signal and a second level Ivfo3 of the second reference signal from a reproducing signal reproduced from the optical disk;
• and
• determining a balance value Kl according to the following equation:
• Kl=(Ivfo1−Ivfo3)I(Ivfo1+Ivfo3);
• and
• detecting the tracking error based upon the balance value Kl.

A method of detecting a tilt error of an apparatus for reproducing data from an optical disk in accordance with a subtraction signal RF_pp having a first reference signal and a second reference signal which are recorded to deviate from a center of a track in opposite directions and which have the same pattern, the method comprising:

• determining a first level Ivfo1 of the first reference signal and a second level Ivfo3 of the second reference signal from a subtraction signal RF_pp reproduced from the optical disk;
• determining a balance value Kl according to the following equation:
• Kl=(Ivfo1−Ivfo3)I(Ivfo1+Ivfo3);
• and
• detecting the tilt error based upon the balance value Kl.

A method for recording data on and/or reproducing data from a disk in which a recording area is divided into sectors, each sector has a header for indicating an address, each header has a first header and a second header which are recorded to deviate from a center of a track in opposite directions, and the first header and the second header have address areas in which address signals of the sectors are recorded and synchronous signal areas in which synchronous signals for detecting the address signals recorded in the address area are recorded, the method comprising:

• generating a reproducing signal including sum signals V1 and V2 of radial pairs of detecting elements, a sum signal RF_sum of the detecting elements, and a push-pull signal RF_pp of the detecting elements, from an optical signal reflected from the disk;
• generating a header area signal having a header area from the reproducing signal received from the reproducing signal generator;
• detecting a first synchronous signal level by detecting a first magnitude Ivfo1 of a first synchronous signal in the first header;
• detecting a second synchronous signal level by detecting a second magnitude Ivfo3 of a second synchronous signal in the second header;
• and
• calculating a balance value Kl, of the magnitude Ivfo1 of the first synchronous signal and the magnitude Ivfo3 of the second synchronous signal.