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:
Sep. 29, 1998
Filed:
Jul. 23, 1996
Tadashi Eguchi, Tokyo, JP;
Akira Torisawa, Machida, JP;
Koichi Egara, Tokyo, JP;
Akihiro Koyama, Yokohama, JP;
Takahiro Hachisu, Yokohama, JP;
Akane Yokota, Yokohama, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A matched filter has an input IDT and an output IDT, and also has a device for preventing propagating surface acoustic waves from diverging. By preventing the divergence of surface acoustic waves, signals obtained in units of electrode finger pairs of the output IDT are uniformed. Furthermore, this application also discloses the following arrangement. That is, an arrangement for converging surface acoustic waves is adopted, and the width of surface acoustic waves input to the output IDT is set to be larger than at least the crossing width of electrode fingers, nearest to the input IDT, of those of the output IDT, so that some surface acoustic waves propagate along non-crossing portions of the electrode fingers, on the input IDT side, of those of the output IDT. With this arrangement, the influence of the crossing portions of the electrode fingers, closer to the input IDT, on the surface acoustic waves input to the crossing portions of the electrode fingers, farther from the input IDT, can be relaxed.