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. 18, 1977
Filed:
Jun. 30, 1975
Applicant:
Inventors:
Frederik Ate De Jonge, Eindhoven, NL;
Willem Frederik Druijvesteijn, Eindhoven, NL;
Antonius Gerardus Verhulst, Eindhoven, NL;
Assignee:
U.S. Philips Corporation, New York, NY (US);
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
G11C / ;
U.S. Cl.
CPC ...
3401 / ;
Abstract
A recording device in which hollow magnetic domains are produced in plates of, for example, orthoferrite by means of a magnetic field. The region within which the field can vary without said domains disappearing depends upon the coercive force of the material. Field variations cause a particular irreversible variation in the domain dimensions, provided a certain minimum coercive force is present. In particular, in order to increase the stability of a hollow domain, a single-walled domain is present within it.