Optical information recording-reproducing method and apparatus including focusing and/or tracking control depending on a determined state of an optical spot

In an optical information recording-reproducing apparatus or method, a sum signal is generated from a divided sensor to be used for auto-focus (AF) and/or auto-tracking (AT) control. The AF servo is closed after an objective lens is moved to a location in the neighborhood of an in-focus position whi...

Full description

Saved in:
Bibliographic Details
Main Author SHIKICHI; SATOSHI
Format Patent
LanguageEnglish
Published 12.12.1995
Edition6
Subjects
INFORMATION STORAGE
INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORDCARRIER AND TRANSDUCER
PHYSICS
Online AccessGet full text

Cover

More Information
Summary:In an optical information recording-reproducing apparatus or method, a sum signal is generated from a divided sensor to be used for auto-focus (AF) and/or auto-tracking (AT) control. The AF servo is closed after an objective lens is moved to a location in the neighborhood of an in-focus position while working a position servo for an objective lens actuator using the sum signal. Further, the fact that a light spot is on a track is detected from the sum signal. If this fact is detected as well as the fact that a tracking error signal is in the neighborhood of zero, the AT servo is closed.
Bibliography:Application Number: US19930022157