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:
Jun. 25, 2002
Filed:
Feb. 20, 1998
Amir Alon, Sunnyvale, CA (US);
Tatiana Kosoburd, Lod, IL;
Zen Research (Ireland), Ltd., Dublin, IE;
Abstract
An optical pickup for simultaneously reading a plurality of data tracks of an optical storage medium is provided. The optical pickup uses a diffractive element to split an illumination beam into a plurality of reading beams which are projected onto a plurality of tracks of the optical storage medium. Apparatus and methods are shown for improving the optical characteristics of the optical pickup by reducing vignetting, optical aberrations, and field curvature. These improvements are achieved by relocating the diffractive element at a greater distance from the laser source, so that a diffractive element having a larger period, and a smaller angle between diffractive orders may be used. The apparatus and methods shown also reduce the number of components and the manufacturing cost of the optical pickup.