The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 22, 2000
Filed:
Jun. 30, 1998
Yasuaki Morimoto, Kawasaki, JP;
Fujitsu Ltd., Kawasaki, JP;
Abstract
An optical information storage unit for reproducing information recorded on a magneto-optic recording medium having a land and a groove as recording tracks, is provided with at least one of first and second systems, where the first system includes a 1/2 wave plate which is arranged so that a crystal optical axis of the 1/2 wave plate and an electrical vector of a light beam emitted from a light source forms approximately 45 degrees, where the 1/2 wave plate being removable from a position of the light beam, and the second system is arranged with the 1/2 wave plate so that the crystal optical axis of the 1/2 wave plate and the electrical vector of the light beam emitted from the light source forms approximately 45 degrees, where the 1/2 wave plate is movable so that another 1/2 wave plate can move to the position of the light beam so that a crystal optical axis of the other 1/2 wave plate is parallel to or perpendicular to the electrical vector. An electrical vector of the light beam irradiated on the magneto-optic recording medium is set so that the electrical vector is perpendicular to a direction in which a recorded signal flows when reproducing the signal from the land and is parallel to the direction in which the recorded signal flows when reproducing the signal from the groove.