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US4549107A Expired / Lapsed US ⏱️ 0.0 years remaining

Ultrasonic beam focusing device with a concave surface

Assignee: Toshiba Corp
•
Filing: 1985-02-07
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Granted: 1985-10-22
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Expires: 2005-02-07
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Abstract

Abstract An ultrasonic beam focusing device with a concave surface comprises a cylindrical housing, a circular piezoelectric polymer film curved to have a concave shape relative to an acoustically active surface thereof and having a pair of circular electrodes at two surfaces thereof, for generating an ultrasonic beam focused at a point and for transducing the received ultrasonic beam into electric signals, leads respectively connected to the electrodes, a rigid polyurethane layer formed in tight contact with an electrode inside the housing at the side of an acoustically inactive surface of the piezoelectric polymer film, for absorbing an ultrasonic beam at the side of the acoustically inactive surface and for supporting the piezoelectric polymer film, and an insulating layer formed in contact with an electrode for electrically insulating the electrode.

Inventors

  • 👤 Nagao Kaneko
  • 👤 Yoshinori Fujimori
  • 👤 Seizaburo Shimizu
  • 👤 Shin Obara

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 15:38
CPC Classifications
G; G10; G10K; G10K11/00; G10K11/18; G10K11/26; G10K11/32; G10K11/002; Y; Y10; Y10S; Y10S310/00; Y10S310/80

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 195 words
A λ/2 wavelength mode ultrasonic beam focusing device with a concave surface comprising: a cylindrical housing having a step inside a distal end thereof; a circular piezoelectric polymer film which is formed contiguously with said step, which is curved in a concave form raltive to an acoustically active surface thereof, and which has a pair of circular electrodes at two respective surfaces thereof, said piezoelectric polymer film generating, in response to a signal applied to said electrodes, an ultrasonic beam, which is focused at a single point, and transducing a received ultrasonic beam into an electric signal; leads respectively connected to said electrodes; a rigid polyurethane supporting substrate which is filled in said housing so as to directly contact said electrode which is at the side of an acoustically inactive surface of said piezoelectric polymer film, said rigid polyurethane layer absorbing an ultrasound beam at the side of the acoustically inactive surface and supporting said piezoelectric polymer film; and an insulating layer which is formed to be in contact with said electrode inside said housing which is at the side of said acoustically active surface of said piezoelectric polymer film for electrically insulating said electrode.
Claim 2
Dependent Claim 195 words
A λ/2 wavelength mode ultrasonic beam focusing device with a concave surface comprising: a cylindrical housing having a step inside a distal end thereof; a circular piezoelectric polymer film which is formed contiguously with said step, which is curved in a concave form raltive to an acoustically active surface thereof, and which has a pair of circular electrodes at two respective surfaces thereof, said piezoelectric polymer film generating, in response to a signal applied to said electrodes, an ultrasonic beam, which is focused at a single point, and transducing a received ultrasonic beam into an electric signal; leads respectively connected to said electrodes; a rigid polyurethane supporting substrate which is filled in said housing so as to directly contact said electrode which is at the side of an acoustically inactive surface of said piezoelectric polymer film, said rigid polyurethane layer absorbing an ultrasound beam at the side of the acoustically inactive surface and supporting said piezoelectric polymer film; and an insulating layer which is formed to be in contact with said electrode inside said housing which is at the side of said acoustically active surface of said piezoelectric polymer film for electrically insulating said electrode.
Claim 3
Dependent Claim 19 words
An ultrasonic beam focusing device according to claim 1, wherein said rigid polyurethane layer is made of foamed polyurethane.
Claim 4
Dependent Claim 26 words
An ultrasonic beam focusing device according to claim 2, wherein said piezoelectric polymer film has an acoustic impedance greater than that of said foamed polyurethane layer.
Claim 5
Dependent Claim 25 words
An ultrasonic beam focusing device according to claim 3, wherein said piezoelectric polymer film comprises one of polyvinylidene fluoride and a copolymer thereof with trifluoroethylene.
Claim 6
Dependent Claim 19 words
An ultrasonic beam focusing device according to claim 4, wherein said electrodes are formed by sputtering or vacuum evaporation.
Claim 7
Dependent Claim 23 words
An ultrasonic beam focusing device according to claim 5, wherein said leads are connected to said electrodes by a conductive epoxy resin adhesive.
Claim 8
Dependent Claim 19 words
An ultrasonic beam focusing device according to claim 4, wherein said electrodes are formed by coating a conductive paint.
Claim 9
Dependent Claim 23 words
An ultrasonic beam focusing device according to claim 7, wherein said leads are connected to said electrodes by a conductive epoxy resin adhesive.

References Cited (Backward Citations)

US3950660A Cited
US3969927A Cited
US3995179A Cited
JPS5325389A Cited
US4296349A Cited
EP0015886A1 Cited
US4383194A Cited
JPS55163999A Cited
EP0037877A1 Cited
US4297607A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1988-10-21 1989-04-22 1989-10-22 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1992-10-21 1993-04-22 1993-10-22 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1996-10-21 1997-04-22 1997-10-22 $7700.00 Window Closed / Lapsed

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