Method of forming a resonance transducer

• US 6,772,490 B2
• Filed: 08/03/2001
• Issued: 08/10/2004
• Est. Priority Date: 07/23/1999
• Status: Expired due to Term

• Current Assignee: Measurement Specialties, Inc. (France) (TE Connectivity Limited)
• Original Assignee: Measurement Specialties, Inc. (France) (TE Connectivity Limited)
• Inventors: Toda, Minoru
• Primary Examiner(s): Tugbang, A. Dexter
• Assistant Examiner(s): KIM, PAUL D
• Application Number:
  US09/922,111
• Publication Number:
  US 20020027400A1
• Time in Patent Office: 1,103 Days
• Field of Search: 29/253.5, 295/921, 295/94, 296/091, 310/327, 310/334, 310/335
• US Class Current: 29/25.35
• CPC Class Codes: B06B 1/067 which is used as, or combined with, an impedance matching layer
• CPC Class Codes: G10K 11/02 Mechanical acoustic impedances; Impedance matching, e.g. by horns; Acoustic resonators
• CPC Class Codes: Y10T 29/42 Piezoelectric device making
• CPC Class Codes: Y10T 29/49002 Electrical device making
• CPC Class Codes: Y10T 29/49005 Acoustic transducer
• CPC Class Codes: Y10T 29/4908 Acoustic transducer

Abstract

A method of forming a resonance transducer comprises providing a piezoelectric body having a first acoustic impedance and a propagation medium having a second acoustic impedance. A matching layer is coupled between the piezoelectric body and the propagation medium. The body vibrating at the resonance frequency has a resonance impedance less than the second acoustic impedance of the propagation medium. The matching layer has a third acoustic impedance less than the second acoustic impedance for providing a high output or high sensitivity signal when operated at the resonance frequency.

Claims

1. A method of forming a resonance transducer, said method comprising:

providing a piezoelectric body having a first acoustic impedance indicative of material characteristics of said piezoelectric body;

providing a propagation medium having a second acoustic impedance; and

coupling a matching layer between said piezoelectric body and said propagation medium, wherein said piezoelectric body vibrating at the resonance frequency has a resonance impedance less than said second acoustic impedance associated with said propagation medium, and wherein said matching layer has a third acoustic impedance less than said second acoustic impedance associated with said propagation medium for providing a high output or high sensitivity signal to said medium when operated at the resonance frequency.

2. The method according to claim 1, wherein the step of coupling a matching layer between said piezoelectric body and said propagation medium comprises providing a first layer of material of thickness t1 and acoustic impedance Z1 and having an inner surface coupled to a front surface of said vibrator body and a second layer of material of thickness t2 and acoustic impedance Z2 and having an outer surface coupled to said radiation medium, wherein the acoustic impedance Z2 is greater than the acoustic impedance Z1 so as to provide a combined impedance of the matching layer at the front surface of the piezoelectric body which is less than the acoustic impedance of the radiation medium.