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:
Feb. 14, 1978
Filed:
Aug. 27, 1976
Applicant:
Inventors:
Christiaan H Velzel, Eindhoven, NL;
Peter F Greve, Eindhoven, NL;
Assignee:
U.S. Philips Corporation, New York, NY (US);
Attorneys:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04N / ; G11B / ;
U.S. Cl.
CPC ...
358128 ; 1791 / ; 350194 ; 250201 ;
Abstract
An apparatus is described for reading a record carrier on which information is stored in an optically readable reflecting structure. By projecting two radiation spots one before and one behind the plane of the information structure, it is possible to ascertain whether a read beam is properly focussed on the information structure. An optical wedge-field lens combination extends the range of operation of the focus correction device.
Velzel, Christiaan. (1978). Apparatus for optically reading a record carrier and correcting focus (U.S. Patent No. 4074314). U.S. Patent and Trademark Office. https://idiyas.com/patent/badge/4074314
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile