Ultrasound transducer and ultrasound probe

Patent metadata

Field	Value
Publication number	US-9924925-B2
Application number	US-201715482062-A
Country	US
Kind code	B2
Filing date	Apr 7, 2017
Priority date	Apr 30, 2015
Publication date	Mar 27, 2018
Grant date	Mar 27, 2018

Abstract

Provided is an ultrasound transducer for irradiating a subject with ultrasound and receiving an ultrasound echo reflected from the subject. The ultrasound transducer includes a plurality of piezoelectric elements configured to emit ultrasound according to input of an electric signal and convert ultrasound incident from outside into an electric signal, and a mask portion provided between the plurality of piezoelectric elements and a radiation surface of the ultrasound on the ultrasound transducer. The mask portion is configured to: mask any divided region among a plurality of divided regions obtained by dividing an elevation direction orthogonal to a plane parallel to a scanning direction of the ultrasound; reflect the ultrasound in a direction different from a propagation direction of the ultrasound on the masked division region; and allow the ultrasound to pass in the propagation direction in the plurality of divided regions except the masked divided region.

First claim

What is claimed is:

1. An ultrasound transducer for irradiating a subject with ultrasound and receiving an ultrasound echo reflected from the subject, the ultrasound transducer comprising:
a plurality of piezoelectric elements configured to emit ultrasound according to input of an electric signal and convert ultrasound incident from outside into an electric signal; and
a mask provided between the plurality of piezoelectric elements and a radiation surface of the ultrasound on the ultrasound transducer, the mask being configured to:
mask any divided region among a plurality of divided regions obtained by dividing an elevation direction orthogonal to a plane parallel to a scanning direction of the ultrasound;
reflect the ultrasound in a direction different from a propagation direction of the ultrasound on the masked division region; and
allow the ultrasound to pass in the propagation direction in the plurality of divided regions except the masked divided region;

wherein the mask comprises:
a plurality of electret portions arrayed along the elevation direction and configured to maintain electric polarization to generate an electric field;
a plurality of hollow portions each forming a strip-shaped hollow space in accordance with arrangement of each of the plurality of electret portions; and
a plurality of counter electrodes facing the plurality of electret portions and each having a strip shape.

2. The ultrasound transducer according to claim 1 , wherein the plurality of piezoelectric elements is one-dimensionally arrayed.

3. The ultrasound transducer according to claim 1 , further comprising:
an acoustic matching layer configured to perform acoustic impedance matching between the plurality of piezoelectric elements and an observation target; and
an acoustic lens configured to emit the ultrasound passed through the mask to outside,
wherein the acoustic lens is stacked on the mask, the mask is stacked on the acoustic matching layer, and the acoustic matching layer is stacked on the plurality of piezoelectric elements.

4. An ultrasound probe comprising the ultrasound transducer according to claim 1 at a distal end of the ultrasound probe.

5. The ultrasound probe according to claim 4 , wherein
the ultrasound probe is an ultrasound endoscope comprising an insertion portion, and
the insertion portion has the ultrasound transducer at a distal end of the insertion portion and is configured to be inserted into the subject.

Assignees

• Olympus Corp

Inventors

• Fujimura Takanao

Classifications

• A61B1/00045

  Display arrangement · CPC title

• A61B8/4494

  characterised by the arrangement of the transducer elements · CPC title

• A61B8/4281

  characterised by sound-transmitting media or devices for coupling the transducer to the tissue · CPC title

• H04R17/00

  Piezoelectric transducers; Electrostrictive transducers (piezoelectric or electrostrictive elements in general H10N30/00; details of piezoelectric or electrostrictive motors, generators or positioners {H10N30/00}) · CPC title

• G10K11/30

  using refraction, e.g. acoustic lenses · CPC title