Matching region for damped piezoelectric ultrasonic apparatus

Claim 2

In an apparatus wherein ultrasonic energy is communicated between an ultrasonic transducer and a transmission medium, the improvement comprising: a matching region disposed between a surface of said transducer and said medium, said matching region including a layer having a multiplicity of tapered elements, each of said elements tapering down in size in the direction away from said transducer and toward said medium; a damping material; and another matching region disposed between an opposing surface of said transducer and said damping material, said another matching region including another layer having a multiplicity of tapered elements, each of said elements of said another layer tapering down in size away from said transducer.

Claim 3

Apparatus as defined by claim 1, wherein each of said multiplicity of tapered elements comprise side-by-side generally wedge-shaped elements that are elongated in the plane perpendicular to the axis of said transducer.

Claim 4

Apparatus as defined by claim 1, wherein each of said multiplicity of tapered elements comprises a multiplicity of generally cone-shaped elements.

Claim 5

Apparatus as defined by claim 1, wherein said elements are disposed in a regular pattern and have a spacing therebetween which is equal to or less than about the wavelength of the highest frequency ultrasound to be transmitted by said transducer.

Claim 6

Apparatus as defined by claim 2, wherein said elements are disposed in a regular pattern and have a spacing therebetween which is equal to or less than about the wavelength of the highest frequency ultrasound to be transmitted by said transducer.

Claim 7

Apparatus as defined by claim 3, wherein said elements are disposed in a regular pattern and have a spacing therebetween which is equal to or less than about the wavelength of the highest frequency ultrasound to be transmitted by said transducer.

Claim 8

Apparatus as defined by claim 1, wherein each of said layers has said multiplicity of tapered elements disposed on the surface thereof which faces away from said transducer, and wherein the wedge angle formed at the bases of said elements with respect to the direction of the axis of said transducer is less than about 20 degrees.

Claim 9

Apparatus as defined by claim 2, wherein each of said layers has said multiplicity of tapered elements disposed on the surface thereof which faces away from said transducer, and wherein the wedge angle formed at the bases of said elements with respect to the direction of the axis of said transducer is less than about 20 degrees.

Claim 10

Apparatus as defined by claim 3, wherein each of said layers has said multiplicity of tapered elements disposed on the surface thereof which faces away from said transducer, and wherein the wedge angle formed at the bases of said elements with respect to the direction of the axis of said transducer is less than about 20 degrees.

Claim 11

Apparatus as defined by claim 4, wherein each of said layers has said multiplicity of tapered elements disposed on the surface thereof which faces away from said transducer, and wherein the wedge angle formed at the bases of said elements with respect to the direction of the axis of said transducer is less than about 20 degrees.

Claim 12

Apparatus as defined by claim 1, wherein said medium comprises a plastic focusing lens, and wherein said matching region further includes a plastic adhesive disposed between said layer and said lens.

Claim 13

Apparatus as defined by claim 4, wherein said medium comprises a plastic focusing lens, and wherein said matching region further includes a plastic adhesive disposed between said layer and said lens.

Claim 14

Apparatus as defined by claim 7, wherein said medium comprises a plastic focusing lens, and wherein said matching region further includes a plastic adhesive disposed between said layer and said lens.

Claim 15

Apparatus as defined by claim 10, wherein said medium comprises a plastic focusing lens, and wherein said matching region further includes a plastic adhesive disposed between said layer and said lens.

Claim 16

Apparatus as defined by claim 1, wherein said medium is water.

Claim 17

Apparatus as defined by claim 4, wherein said medium is water.

Claim 18

Apparatus as defined by claim 7, wherein said medium is water.

Claim 19

Apparatus as defined by claim 1, wherein said layer is formed of tin-lead solder.

Claim 20

Apparatus as defined by claim 4, wherein said layer is formed of tin-lead solder.

Claim 21

Apparatus as defined by claim 7, wherein said layer is formed of tin-lead solder.

Claim 22

Apparatus as defined by claim 11, wherein said layer is formed of tin-lead solder.

Claim 23

Apparatus as defined by claim 1, wherein the material of said layer is selected as having: an acoustic impedance that is approximately the same as the acoustic impedance of said transducer; and an ultrasound propagation velocity that is approximately the same as the ultrasound propagation velocity of said medium.

Claim 24

Apparatus as defined by claim 4, wherein the material of said layer is selected as having: an acoustic impedance that is approximately the same as the acoustic impedance of said transducer; and an ultrasound propagation velocity that is approximately the same as the ultrasound propagation velocity of said medium.

Claim 25

Apparatus as defined by claim 7, wherein the material of said layer is selected as having: an acoustic impedance that is approximately the same as the acoustic impedance of said transducer; and an ultrasound propagation velocity that is approximately the same as the ultrasound propagation velocity of said medium.

Claim 26

Apparatus as defined by claim 11, wherein the material of said layer is selected as having: an acoustic impedance that is approximately the same as the acoustic impedance of said transducer; and an ultrasound propagation velocity that is approximately the same as the ultrasound propagation velocity of said medium.

Claim 27

Apparatus for investigating a body to determine characteristics thereof, comprising: means for generating energizing signals; an ultrasonic transducer coupled to said energizing means for generating a beam of ultrasonic energy for transmission into said body, receiving ultrasound energy reflected from the body, and converting the received ultrasound energy to electrical signals; means for processing said electrical signals to produce representations of the body characteristics; a transmission medium between said transducer and said body; and a matching region disposed between a surface of said transducer and said medium, said matching region including a layer having a multiplicity of tapered elements, each of said elements tapering down in size in the direction away from said transducer and toward said medium; a damping material; and another matching region disposed between an opposing surface of said transducer and said damping material, said another matching region including another layer having a multiplicity of tapered elements, each of said elements of said another layer tapering down in size away from said transducer.

Claim 28

Apparatus for investigating a body to determine characteristics thereof, comprising: means for generating energizing signals; an ultrasonic transducer coupled to said energizing means for generating a beam of ultrasonic energy for transmission into said body, receiving ultrasound energy reflected from the body, and converting the received ultrasound energy to electrical signals; means for processing said electrical signals to produce representations of the body characteristics; a transmission medium between said transducer and said body; and a matching region disposed between a surface of said transducer and said medium, said matching region including a layer having a multiplicity of tapered elements, each of said elements tapering down in size in the direction away from said transducer and toward said medium; a damping material; and another matching region disposed between an opposing surface of said transducer and said damping material, said another matching region including another layer having a multiplicity of tapered elements, each of said elements of said another layer tapering down in size away from said transducer.

Claim 29

Apparatus as defined by claim 26 wherein said transducer is formed of lead zirconate titanate, said medium comprises a plastic focusing lens, said layer comprises tin-lead solder, and said matching region further includes a plastic adhesive disposed between said layer and said lens.

Claim 30

Apparatus as defined by claim 27 wherein said damping material is tungsten filled epoxy.

Claim 31

Apparatus as defined by claim 27, wherein each of said multiplicity of tapered elements comprise side-by-side generally wedge-shaped elements that are elongated in the plane perpendicular to the axis of said transducer.

Claim 32

Apparatus as defined by claim 27, wherein each of said multiplicity of tapered elements comprise side-by-side generally wedge-shaped elements that are elongated in the plane perpendicular to the axis of said transducer.

Claim 33

Apparatus as defined by claim 26, wherein each of said multiplicity of tapered elements comprises a multiplicity of generally cone-shaped elements.

Claim 34

Apparatus as defined by claim 28, wherein each of said multiplicity of tapered elements comprises a multiplicity of generally cone-shaped elements.

Claim 35

Apparatus as defined by claim 26, wherein said elements are disposed in a regular pattern and have a spacing therebetween which is equal to or less than about the wavelength of the highest frequency ultrasound to be transmitted by said transducer.

Claim 36

Apparatus as defined by claim 28, wherein said elements are disposed in a regular pattern and have a spacing therebetween which is equal to or less than about the wavelength of the highest frequency ultrasound to be transmitted by said transducer.

Claim 37

Apparatus as defined by claim 30, wherein said elements are disposed in a regular pattern and have a spacing therebetween which is equal to or less than about the wavelength of the highest frequency ultrasound to be transmitted by said transducer.

Claim 38

Apparatus as defined by claim 26, wherein said layer has said multiplicity of tapered elements disposed on the surface thereof which faces away from said transducer, and wherein the wedge angle formed at the bases of said elements with respect to the direction of the axis of said transducer is less than about 20 degrees and the tapered elements are longer than about two wavelengths of the ultrasound energy.

Claim 39

Apparatus as defined by claim 28, wherein said layer has said multiplicity of tapered elements disposed on the surface thereof which faces away from said transducer, and wherein the wedge angle formed at the bases of said elements with respect to the direction of the axis of said transducer is less than about 20 degrees and the tapered elements are longer than about two wavelengths of the ultrasound energy.

Claim 40

Apparatus as defined by claim 31, wherein said layer has said multiplicity of tapered elements disposed on the surface thereof which faces away from said transducer, and wherein the wedge angle formed at the bases of said elements with respect to the direction of the axis of said transducer is less than about 20 degrees and the tapered elements are longer than about two wavelengths of the ultrasound energy.

Claim 41

Apparatus as defined by claim 26, wherein said layer is formed of tin-lead solder.

Claim 42

Apparatus as defined by claim 26, wherein the material of said layer is selected as having: an acoustic impedance that is approximately the same as the acoustic impedance of said transducer; and an ultrasound propagation velocity that is approximately the same as the ultrasound propagation velocity of said medium.

Claim 43

Apparatus as defined by claim 28, wherein the material of said layer is selected as having: an acoustic impedance that is approximately the same as the acoustic impedance of said transducer; and an ultrasound propagation velocity that is approximately the same as the ultrasound propagation velocity of said medium.

Claim 44

Apparatus as defined by claim 31, wherein the material of said layer is selected as having: an acoustic impedance that is approximately the same as the acoustic impedance of said transducer; and an ultrasound propagation velocity that is approximately the same as the ultrasound propagation velocity of said medium.

Claim 45

In an apparatus wherein ultrasonic energy is to be communicated between an ultrasonic transducer and a transmission medium adjacent to one surface of said transducer, the improvement comprising: a damping material located adjacent the opposing surface of said transducer; a matching region disposed between said opposing surface of said transducer and said damping material, said matching region including a layer having a multiplicity of tapered elements, each of said elements tapering down in size in the direction away from said transducer and toward said damping material.

Claim 46

In an apparatus wherein ultrasonic energy is to be communicated between an ultrasonic transducer and a transmission medium adjacent to one surface of said transducer, the improvement comprising: a damping material located adjacent the opposing surface of said transducer; a matching region disposed between said opposing surface of said transducer and said damping material, said matching region including a layer having a multiplicity of tapered elements, each of said elements tapering down in size in the direction away from said transducer and toward said damping material.

Claim 47

Apparatus as defined by claim 43, wherein said transducer is a lead zirconate titanate transducer, said layer comprises tin-lead solder, and said damping material is tungsten filled epoxy.

Claim 48

Apparatus as defined by claim 43, wherein said transducer is a lead zirconate titanate transducer, said layer comprises tin-lead solder, and said damping material is tungsten filled epoxy.

Claim 49

Apparatus as defined by claim 44, wherein said transducer is a lead zirconate titanate transducer, said layer comprises tin-lead solder, and said damping material is tungsten filled epoxy.

Claim 50

Apparatus as defined by claim 43 wherein said multiplicity of tapered elements comprises a multiplicity of generally cone-shaped elements.

Claim 51

Apparatus as defined by claim 44 wherein said multiplicity of tapered elements comprises a multiplicity of generally cone-shaped elements.