Title:
【発明の名称】超音波振動子及びその製造方法
Document Type and Number:
Japanese Patent JP2974815
Kind Code:
B2
Abstract:
PURPOSE:To secure the acoustic matching with ultrasonic propagation media such as water, etc., by distributing the circular opening rate in the ultrasonic radiation direction. CONSTITUTION:A porous PZT ceramic layer 10 of the ultrasonic vibrator transducer is the layer in which the circular opening rate changes. Namely, in the vicinity of the center part of the porous PZT ceramic layer 10, the circular opening rate is 19% which is low, and in the vicinity of an electrode 12, the circular opening rate is 51% which is high. In the portion where the circular opening rate is 19%, the acoustic impedance becomes 14kg/m<2> which becomes relatively high value. In the portion where the circular opening rate is 51%, the acoustic impedance becomes 4.5kg/m<2> which becomes the value relatively near to water. In this case, the power existing in the porous PZT ceramic layer 10 is injected. When the mechanical distortion is generated by this power, the stress relating to this distortion becomes conspicuous in the center part. Therefore, the mechanical strength is secured in the center part.
Inventors:
KUMAMOTO SUSUMU
MIZUMURA KOICHI
OKUNO KYONORI
MIZUMURA KOICHI
OKUNO KYONORI
Application Number:
JP11188491A
Publication Date:
November 10, 1999
Filing Date:
May 16, 1991
Export Citation:
Assignee:
NIPPON MUSEN KK
International Classes:
H04R17/00; H01L41/193; H04R31/00; (IPC1-7): H04R31/00; H01L41/193; H04R17/00
Domestic Patent References:
| JP213098A | ||||
| JP1107584A |
Attorney, Agent or Firm:
Toshihiko Kanayama (2 outside)