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:
Jan. 27, 1987
Filed:
Apr. 07, 1982
Applicant:
Inventor:
Kunio Goto, Yokohama, JP;
Assignee:
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G11B / ; G11B / ;
U.S. Cl.
CPC ...
369 14 ; 360 75 ; 360 77 ; 360110 ; 369 43 ;
Abstract
The lateral position of a magnetic head is controlled in response to tracking information derived from an adjacent guide track formed by a series of minute pits on a grooveless recording medium having ferromagnetic and dielectric properties. Microwave energy is applied to an electrode mounted for movement with the magnetic head to sense the variations in capacitance resulting from the geometrical variations of the minute pits. The recording medium comprises an underlying layer of ferromagnetic material in which the minute pits are formed in spiral or concentric pattern and an overlying layer of a dielectric material which conforms to the pit contours of the underlying layer.