METHODS AND APPARATUS FOR DETECTING AND CORRECTING MAGNIFICATION ERROR IN A MULTI-BEAM OPTICAL DISK DRIVE

摘要

Methods and apparatus are provided for detecting and correcting magnification errors while simultaneously reading or writing multiple data tracks with a multi-beam optical disk drive. An optical head for the optical disk drive includes a plurality of laser diodes that generate multiple light beams for reading from or writing to the optical disk, means for detecting a magnification error, and means for compensating for the magnification error to align the multiple light beams with multiple data tracks. A number of optomechanical systems are provided for correcting the magnification errors in the beams.