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:
Jul. 28, 1992
Filed:
Jan. 08, 1991
Applicant:
Inventors:
Keith B Jefferts, Shaw Island, WA (US);
Philip A Ekstrom, Shaw Island, WA (US);
Assignee:
Northwest Marine Technology Inc., Shaw Island, WA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01R / ; G01R / ;
U.S. Cl.
CPC ...
324247 ; 324253 ; 340573 ;
Abstract
An apparatus detects a magnetic tag implanted in an organism as detector is moved past the organism by detecting a magnetic field difference between two positions. Prior to examination of a specimen under test, the outputs of a plurality of loops detecting magnetic fields are balanced in a uniform magnetic field. As a consequence, when one of the coils is exposed to a different magnetic field than the other of the coils this difference is detected and an alarm is sounded to indicate that the magnetic tag has been detected.