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:
Dec. 01, 1992
Filed:
Jul. 17, 1991
Applicant:
Inventors:
Jean-Claude Lehureau, Ste Genevieve des Bois, FR;
Bruno Mourey, Boulogne Billancourt, FR;
Henriette Magna, Antony, FR;
Assignee:
Thomson-CSF, Puteaux, FR;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B / ;
U.S. Cl.
CPC ...
369 4412 ; 369110 ;
Abstract
A device for optically reading a recording medium is provided, in which a polarization beam separator includes a transparent plate having a phase network associated with a birefringent material, the refraction index of this material having a first refraction index for the polarization of an incident beam and a second refraction index for the polarization of a reflected beam. Thus, in accordance with the embodiment, the detection devices are placed substantially along the emission axis of the optical source.