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. 24, 1976
Filed:
Dec. 20, 1973
Leland Dale Green, Sierra Madre, CA (US);
Xerox Corporation, Stamford, CT (US);
Abstract
Reproducing the information stored in the spiral track of a record-type information-bearing disc is achieved by uniformly charging the surface of the disc by means of a corona-generating device disposed in proximity to the disc, and, thereafter, using a conductive stylus riding in the track of the disc to pick up the charge from only the peak points of the track. All peaks are at the same height. The system preferably uses FM encoding, and the information is carried by the track according to the peak-to-peak spacing. The stylus is shaped in relation to the track such that it may not touch the peaks in the track. The stylus contacts the sides of the track for tracking purposes. An air breakdown between the peaks and the metallic portion of the stylus results in the signal picked up by the stylus.