Ultrasonic probe

• US 20040215079A1
• Filed: 12/16/2003
• Published: 10/28/2004
• Est. Priority Date: 12/19/2002
• Status: Active Grant

• Current Assignee: GSK Corporation (Chuan HSIN Investment and Development Company Limited), Olympus Corporation
• Original Assignee: GSK Corporation (Chuan HSIN Investment and Development Company Limited), Olympus Corporation
• Inventors: Mizuguchi, Tohru, Hatano, Koumei, Omura, Masayoshi
• Granted Patent: US 7,400,079 B2
• Time in Patent Office: Days
• US Class Current: 600/459
• CPC Class Codes: G01N 2291/0423 Surface waves, e.g. Rayleigh waves, Love waves
• CPC Class Codes: G01N 29/2456 Focusing probes focusing arrangements G01N29/221
• CPC Class Codes: G01N 29/2468 Probes with delay lines
• CPC Class Codes: G01S 7/521 Constructional features
• CPC Class Codes: G10K 11/002 Devices for damping, suppressing, obstructing or conducting sound in acoustic devices G10K1/06 - G10K1/10 take precedence; for electro-mechanical transducers for communication H04R3/002
• CPC Class Codes: G10K 11/02 Mechanical acoustic impedances; Impedance matching, e.g. by horns; Acoustic resonators

Abstract

An ultrasonic probe includes an ultrasonic transducer which is formed by sequentially laminating an acoustic lens, an acoustic matching layer, a piezoelectric element, and a backing member. The backing member arranged on a surface opposed side of the acoustic matching layer and the acoustic lens arranged to the piezoelectric element contains a synthetic rubber containing a mixture including acrylonitrile-butadiene rubber (NBR), ethylen-propylene terpolymer (EPDM), and at least inorganic fine powders.

Claims

1. An ultrasonic probe comprising an ultrasonic transducer, the ultrasonic transducer further comprising, by sequential lamination:

an acoustic lens;

an acoustic matching layer;

a piezoelectric element; and

a backing member,

wherein the backing member for attenuating ultrasonic waves arranged on a surface opposed side of the acoustic matching layer and the acoustic lens arranged to the piezoelectric element contains a synthetic rubber having a mixture including acrylonitrile-butadiene rubber (NBR), ethylen-propylene terpolymer (EPDM), and at least inorganic fine powders.

2. An ultrasonic probe according to claim 1, wherein the backing member has, as the properties, the hardness of 80 to 100 degrees in the A scale in conformity with JISK6253 and the ultrasonic absorbing coefficient of 10 or more [dB/mm] at the frequency of 5 MHz.

3. An ultrasonic probe according to claim 1, further comprising:

an exterior cap which immerses the ultrasonic transducer in an acoustic medium,

wherein the backing member immersed in the acoustic medium has the percentage of absorption of 2.5% or less and the acoustic impedance within a range of 1×

10⁶ to 8×

10⁶ [kg/(m²·

s)].

4. An ultrasonic probe according to claim 1, further comprising:

a flexible shaft which rotates the ultrasonic transducer by a driving motor.

5. An ultrasonic probe according to claim 1, further comprising:

a coating film which covers the ultrasonic transducer and protects it from the acoustic medium.

6. An ultrasonic probe according to claim 1, wherein the acoustic medium is water with low attenuation of ultrasonic waves, an aqueous solution obtained by adding an additive to the water, or oil with the low attenuation of ultrasonic waves.

7. An ultrasonic probe according to claim 1, wherein the ultrasonic transducer comprises at least:

a piezoelectric element which receives and transmits ultrasonic waves; and

a backing member which is arranged to the rear surface side of the piezoelectric element,

wherein the backing member is a mixture including acrylonitrile-butadiene rubber (NBR), ethylen-propylene terpolymer (EPDM), and at least inorganic fine powders, and

the backing member is a synthetic rubber having, as the properties, the hardness of 80 to 100 degrees in the A scale in conformity with JISK6253 and the ultrasonic absorbing coefficient of 10 or more [dB/mm] at the frequency of 5 MHz.

8. An ultrasonic probe according to claim 1, wherein the ultrasonic transducer comprises at least:

a piezoelectric element which receives and transmits ultrasonic waves; and

a backing member which is arranged to the rear surface side of the piezoelectric element,

wherein the backing member is a mixture including acrylonitrile-butadiene rubber (NBR), ethylen-propylene terpolymer (EPDM), and at least inorganic fine powders,

the backing member is a synthetic rubber having, as the properties, the hardness of the 80 to 100 degrees in the A scale in conformity with JISK6253 and the ultrasonic absorbing coefficient of 10 or more [dB/mm] at the frequency of 5 MHz, and

the backing member further has, the property, the percentage of absorption of 2.5% or less, and the acoustic impedance in the range between 1×

10⁶ to 8×

10⁶ [kg/(m²·

s)].