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:
Jun. 02, 2020
Filed:
Jan. 18, 2016
Applicant:
Hitachi, Ltd., Tokyo, JP;
Inventors:
Assignee:
HITACHI, LTD., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L 41/113 (2006.01); G01S 7/521 (2006.01); H01L 41/09 (2006.01); H04R 17/00 (2006.01); A61B 8/14 (2006.01); H04R 17/10 (2006.01);
U.S. Cl.
CPC ...
H01L 41/113 (2013.01); A61B 8/14 (2013.01); G01S 7/521 (2013.01); H01L 41/09 (2013.01); H04R 17/00 (2013.01); H04R 17/10 (2013.01);
Abstract
A resonance layer () and an acoustic separation layer () are arranged adjacent to each other between a piezoelectric element () and a circuit board () provided with an electronic circuit for driving the piezoelectric element. The acoustic impedance of the resonance layer () is higher than that of the piezoelectric element (), and the acoustic impedance of the acoustic separation layer () is lower than that of the circuit board (). An ultrasonic wave is reflected at the interface between the resonance layer () and the acoustic separation layer () where the difference in acoustic impedance is large, and the ultrasonic wave propagating to the circuit-board () side is reduced.