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:
Mar. 13, 1990
Filed:
Mar. 14, 1989
Peter Coops, Eindhoven, NL;
Adrianus J Duijvestijn, Eindhoven, NL;
U.S. Philips Corporation, New York, NY (US);
Abstract
Optical scanning apparatus which includes a diode laser producing a radiation beam which is focussed by a lens system on a reflecting information plane to be scanned thereby. The reflected radiation is diffracted by a composite diffraction grating which includes a pair of sub-gratings, forming respective radiation spots on respective pairs of radiation detectors. The detectors in each pair are separated by a separating strip, the separating strips being substantially parallel to or co-linear with the bonding line between the sub-gratings. Such arrangement achieves correction for wavelength variations of the radiation beam, as well as fairly wide tolerances in the relative positioning of the various optical elements of the apparatus.