| 摘要 |
The present invention relates to a tracking error detection method for an optical storage system wherein an optical disk comprises a plurality of adjacent track portions with a radial track pattern in which a number n > 2 of adjacent track portions repeatedly exhibit non-uniform radial track distances ( TP<SUB>1</SUB> ? TP<SUB>2</SUB> ? TP<SUB>n </SUB>), whereby the sum of said radial track distances ( TP<SUB>S </SUB>= TP<SUB>1</SUB> + ... + TP<SUB>n</SUB> ) is higher than the reciprocal optical cutoff ? /(2NA) of the optical disk drive. The method comprises projecting a plurality of (n) satellite light spots (S<SUB>1</SUB>,..., S<SUB>n</SUB>; S<SUB>L</SUB>, S<SUB>M</SUB>) and one main spot (S<SUB>R</SUB>) onto said optical disk, each satellite spot being displaced in radial direction off the main spot by another one of half the radial track distances (TP<SUB>1 </SUB>/2 ?TP<SUB>1</SUB>/2 ? ... ? TP<SUB>n</SUB>/2), respectively, and generating push-pull signals (PP<SUB>1</SUB>,...,PP<SUB>n</SUB>; PP<SUB>L</SUB>, <SUB>PPM)</SUB> for each satellite spot. The invention further relates to an optical disk drive implementing said method. |
