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:
Dec. 28, 2004
Filed:
Apr. 10, 2002
Takeaki Itsuji, Kanagawa, JP;
Shunichi Shido, Kanagawa, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A signal detector comprises a frequency changing circuit adapted to receive an electric signal having a frequency modulated from a first reference frequency f with a modulation width &Dgr;f as input, convert the received electric signal to an electric signal having a second reference frequency f lower than the first reference frequency f and output the converted electric signal and a frequency/voltage conversion circuit adapted to receive the output of the frequency changing circuit as input and output a voltage corresponding to the ratio of the modulation width &Dgr;f to the second reference frequency f and an electric signal having a frequency modulated from a reference frequency Nf with a modulation width of N&Dgr;f (N: integer).