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. 25, 1992
Filed:
Jun. 03, 1991
Applicant:
Inventors:
Assignee:
Mitsubishi Mining & Cement Co., Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H04B / ;
U.S. Cl.
CPC ...
367164 ; 310358 ;
Abstract
A piezoelectric transducer having electrodes formed on both surfaces has a piezoelectric base molded as a curved plate which can converge sound fields of acoustic waves at an arbitrary point and which can reduce noise or reverberation in a lateral direction which otherwise occur due to unnecessary vibration. At least one of the electrodes is divided concentrically. A material having a small electromechanical coupling factor K.sub.p in the lateral direction is used for the piezoelectric material, preferably porous PZT.