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:
Jul. 21, 1992
Filed:
Oct. 19, 1990
Claude Tinet, Paris, FR;
Thomson-SA, Paris, FR;
Abstract
The present invention concerns an arrangement for reading an optically readable light reflective carrier on which data is stored in the form of diffractive elements which are deviations from a reference surface. The data elements each have a plurality of adjacent tracks located on the carrier with data elements being positioned on adjacent tracks. The system utilizes an illumination device for projecting a concentrated light spot onto the carrier in order to obtain diffraction of light along the entire length of each of the data elements with an optical arrangement collecting light reflected from a carrier in such a way that light energy which is received when a projected light spot impinges on the reference surface is greater than the light energy received when the projected light spot impinges on a data element.