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:
Feb. 11, 1992
Filed:
Mar. 08, 1990
Applicant:
Inventors:
Kazuhito Kurosawa, Ibaraki, JP;
Mitsutaka Hikita, Tokyo, JP;
Toyoji Tabuchi, Kanagawa, JP;
Nobuhiko Shibagaki, Tokyo, JP;
Tetsuya Hirashima, Ibaraki, JP;
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H03H / ;
U.S. Cl.
CPC ...
333193 ; 3103 / ; 3103 / ; 333196 ;
Abstract
At least one electro-acoustic transducer of a first surface acoustic wave device and acousto-electric transducers of a second surface acoustic wave device are arranged symmetrically to the first surface acoustic wave device about a line parallel to a propagating direction of surface acoustic wave and is phase-weighted differently from the remaining transducers having common phase-weighting, to improve an attenuation for stop frequency.