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:
Oct. 16, 1990
Filed:
May. 01, 1989
Applicant:
Inventor:
Frederick T Buhler, Providence, RI (US);
Assignee:
Conrac SCD, Inc., Durate, CA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01J / ;
U.S. Cl.
CPC ...
315-8 ;
Abstract
A method and apparatus for nulling the magnetic field within a specified volume in the presence of an external ambient field by generating compensating magnetic fields at a number of locations around the volume, sensing the field in the volume and controlling the value of the compensating fields in a closed loop system to null the field within the volume.