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:
Aug. 09, 1994
Filed:
Apr. 13, 1992
Applicant:
Inventor:
Kenichi Takahira, Itami, JP;
Assignee:
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01Q / ;
U.S. Cl.
CPC ...
343741 ; 343745 ; 343895 ;
Abstract
An antenna circuit for a non-contact IC card exchanges signals with an external device utilizing electromagnetic waves. The antenna circuit includes a coil and a capacitor connected to form a resonant circuit. The coil includes a main coil having a spiral conductive pattern disposed on a peripheral portion of a substrate and a plurality of adjusting patterns, each electrically connecting a portion of the conductive pattern corresponding to a desired number of turns of the main coil to an end of the main coil. The plurality of adjusting patterns are disconnected from the main coil, except for one adjusting pattern, to obtain a coil of desired inductance.