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. 11, 1986
Filed:
Jul. 20, 1984
Thomas H Di Stefano, Bronxville, NY (US);
Halil B Bakoglu, Stanford, CA (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
This optical sensor has cylindrical symmetry and is comprised of a semiconductor light source/light detector combination and an optical element comprising a single lens, where the sensor is particularly suitable for uses in accurate position detection in data recording systems. In a preferred embodiment, the light source is a forward-biased p-n junction, while the light detector is a reverse-biased p-n junction located below the light source and coaxial therewith. Light from the source is directed to a point on a data recording medium and the light reflected therefrom passes through the light source to the light detecting junction. The ac signal corresponding to the reflected light is an indication of the position of the recording head with respect to the data storage medium.