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:
Jan. 13, 1998
Filed:
Sep. 23, 1996
Jun-ichi Takahashi, Tokyo, JP;
NEC Corporation, , JP;
Abstract
An optical head is provided which device has an optical system with which light emitted from a laser source and reflected from a beam splitter is converged onto an optical disk by an objective lens and reflected light is guided to a photo-detector. The optical system includes a beam diameter enlarging lens which enlarges beam diameter of luminous flux incident on the objective lens from the laser source through the beam splitter. The beam diameter enlarging lens may be a conical lens. According to the present invention, it is possible to enlarge the range over which access can be made by the objective lens alone without requiring means such as a lens actuator.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile