OPTICAL INFORMATION RECORDING AND REPRODUCING DEVICE

PURPOSE:To attain the setting of a minimum required gain at respective time needed, by performing a relative movement between an optical beam spot, and the information track of an optical information recording medium at different speed, and switching a tracking servo gain an/or a focusing servo gain...

Full description

Saved in:
Bibliographic Details
Main Authors HOSOYA HIDEKI, SHIKICHI SATOSHI
Format Patent
LanguageEnglish
Published 25.11.1987
Subjects
INFORMATION STORAGE
INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORDCARRIER AND TRANSDUCER
PHYSICS
Online AccessGet full text

Cover

More Information
Summary:PURPOSE:To attain the setting of a minimum required gain at respective time needed, by performing a relative movement between an optical beam spot, and the information track of an optical information recording medium at different speed, and switching a tracking servo gain an/or a focusing servo gain at different speed time. CONSTITUTION:At a recording time, that is, when an output from an amplifier 121-1 passes through a point D, and is inputted to a driver 121-3, an automatic tracking (AT) gain is set so as to have an amplification degree of (gamma). And at a reproducing time, since the output from the amplifier 121-1 passes through a point C, and is inputted to the driver 121-3, the AT gain is formed in a shape that it is raised as a whole, as shown in (delta). The (delta) is decreased by setting a resistance value, etc., between the points C and D appropriately. In this way, the lowering of the dignity of a recording signal based on excessive sensitivity due to an excessive gain at a recording mode time can be prevented.
Bibliography:Application Number: JP19860113512