A tracking circuit for returning an optical beam to a track bein

Aberration correcting apparatus and information recording medium

Aberration correcting apparatus and information reproducing...

Aberration detection device and optical information...

Aberration detection device and optical information...

Aberration detection device, aberration detection method,...

Abnormal track skipping detection and control arrangement

Access control apparatus for optical disk according change of tr

Access control device

Access control method and device of disk unit

Access controlling device for use in an optical disk drive

Accessing apparatus for optical information recording and reprod

Acquiring a best focus using a focus signal offset

Acquiring focus in an optical disk system using a time and shape

Acquiring focus in an optical system using a soft focus acquirin

Acquiring focus in optical systems using a focus error signal an

Acting track-crossing during tracking error adjust

Active tracking system for optical disk storage

Actively athermalized optical head assembly

Actuator