JPH0234155A - Omni-directional ultrasonic probe - Google Patents

Abstract

PURPOSE: To conduct continuous blood testing without any need to aim by transmitting and receiving all around directionally and continuously by using continuous wave ultrasonic signals. CONSTITUTION: A transducer 36 is connected to a wire pair 60 to use for transmitting a continuous wave acoustic signal. The continuous wave acoustic signal reflected from an acoustic reflector at the outside of a probe is received by a transducer 52. A reflect member 72 reflects the continuous wave acoustic energy from the probe at an angle to be measured on a lengthwise directional axial line of the probe 12, and receives an acoustic reflective wave from an outer acoustic reflector in a path with an operating angle for a lengthwise directional axial line of the probe, which are reflected to the transducer.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an ultrasonic probe for use within the body of an animal (including humans and non-humans), and particularly, but not exclusively, to the field of the invention. The present invention relates to a device attached to the end of a hollow catheter and removably placed in the esophagus for use in detecting the velocity of an acoustic reflector within a range by the Doppler effect.

SUMMARY OF THE INVENTION The present invention satisfies a general need in this type of device by providing a new and improved omnidirectional ultrasound probe. The present invention relates to a standard esophageal stethoscope. In certain applications, it is used to measure blood velocity in the descending aorta. This kind of speed measurement is
For example, it could be used by an anesthesiologist in controlling anesthetics administered to a patient whose blood flow is being measured by the device of the invention6. Because it performs targeted transmission and reception, there is no need for aiming or adjusting time delays. The device of the present invention also uses one or more surfaces that can be designed at different angles to limit different operating angles and thus to allow ultrasound transmission and reception in different elongated directions.6 However, the present invention In this device, both transmission and reception occur along substantially parallel reflection paths. By allowing different angles of reflection, the device of the present invention is protean so that it can be adapted to a variety of applications. On the other hand, the device of the invention has a relatively simple and economical construction by requiring transmission and reception to take place along substantially parallel paths. The device of the present invention provides this operation with relatively low crosstalk and includes acoustic isolation and matching members and a liquid-filled chamber that improves the efficiency of transmission and reception of continuous wave signals.

The device of the invention is designed to be relatively easily inserted into the object in which it is used. Due to these various characteristics,
The device of the present invention provides a practical probe that can be actually manufactured and used. The present invention therefore provides a probe that has the advantages of the prior art and improves upon the prior art by providing these advantages in a relatively simple, economical and practical construction. I believe that.

The probe of the present invention can be used inside the body of an animal (including a human), and includes a support member and a transmitter coupled to the support member for transmitting a continuous wave ultrasound signal within the body during a test period. a receiver coupled to the support member for receiving a reflection of a continuous wave ultrasound signal reflected from an acoustic reflector within the body (e.g., fluid flowing in the descending aorta) along a receive reflection path; transmitting a continuous wave ultrasound signal from the transmitter into the body, reflecting along a reflection path, and receiving a reflection of the continuous wave ultrasound signal reflected from an acoustic reflector within the body, along a reflection path. an acoustic reflecting means for reflecting to a receiver, and the acoustic reflecting means is arranged with respect to the transmitter and the receiver such that the transmitting and receiving reflection paths are substantially parallel.

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a hollow catheter 2 consisting of an elongated flexible smooth plastic tubular member 4, which is inserted, for example, into the esophagus in a conventional manner. However, the invention can be used in environments other than the esophagus, such as within other internal annular regions of animals. Between the ends of member 4,
There is a perforation section with a plurality of perforations 6. The perforation 6 is protected within a sleeve 8 (heat-shrinkable sleeve). This sleeve is therefore not a seal that prevents liquid from entering the perforation 6, but rather the acoustic signal is
via a conventional stethoscope (
It acts as a diaphragm or membrane through which the auscultation signal is transmitted to a receiving device, such as an auscultation signal (not shown). An auscultatory signal receiving device, such as a stethoscope, is connected to an adapter 10 that defines a portion of the distal or forked end of the catheter 2. In describing the preferred embodiment of the present invention, by way of example only Since it refers to its use in the human esophagus, wA8
The acoustically detectable sounds that can be transmitted to the stethoscope connected to the adapter 10 via the adapter 10 are sounds emanating from the heart and lungs, near which the esophagus passes. However, as mentioned above, the invention has use in other applications.

Connected to the lower or distal end of the catheter 2 is a probe 2 constructed in accordance with the present invention. In a preferred embodiment, probe 12 is an ultrasound signal generating and receiving transducer assembly having one of four specific embodiments illustrated in FIGS. 1-6. 1
One embodiment will be described with reference to FIGS. 1 to 3, and a modification thereof will be described with reference to FIG. 6. Next, another embodiment will be described with reference to FIG. This will be explained with reference to FIG. Like parts in these various embodiments are designated by like reference numbers.

Generally speaking, each of these embodiments includes a support member, a transmitter connected to the support member for transmitting a continuous wave ultrasound signal within the body during a test period, and a probe connected to the support member in which a probe is disposed. a receiver for receiving a reflection of a continuous wave ultrasound signal reflected along a transmission reflection path from an acoustic reflector of the body; and a receiver connected to the support member for reflecting the continuous wave ultrasound signal to a reception reflection path; and an acoustic reflecting means for reflecting the continuous wave ultrasound signal reflected from the body acoustic reflex l/lid along the receiving reflection path to the receiver,
．． The acoustic reflection means is arranged with respect to the transmission means and the reception means such that the transmission reflection path and the reception reflection path are substantially parallel. As used herein, r-transmit reflection path j and r-receive reflection path j refer to the three-dimensional beam pattern defined by or traversed by the ultrasound energy transmitted and received, respectively, according to the present invention. In a preferred embodiment, these patterns are set around the probe. This is because the probe 12 operates in all directions.

Also, a body (7) that transmits the reflection along the r reception reflection path J.
facoustic reflector/lid J refers to something within the range of the probe 12 that can reflect a continuous wave ultrasound signal; is the moving blood flow, and more specifically the moving blood cells, in the descending aorta.An acoustic reflector J of this type in a preferred embodiment is:
It is distinguished from the acoustic reflection means, which is one element of the present invention, and is located outside the probe 12.

In the embodiment shown in FIGS. 1-3, the support member is generally designated by the reference numeral 14. This member 1
4 is an integral member having two parts defined as a hub 16 and a shaft 18 extending axially from the hub. Member 14 is comprised of any suitable material (eg, aluminum, stainless steel, plastic). Hub 16 has a cylindrical outer surface 20 of a diameter suitable for fitting over the distal end of catheter 2. This diameter is such that the hub 16 and the tubular member 4 of the catheter 2 are configured to frictionally engage each other and create a retention force to retain the probe 2 on the catheter 2 from the peripheral flange 22. extends radially outward and abuts the lower end of the catheter 2 when the probe 12 is attached to the catheter 2. Hub 16 has a cylindrical inner surface 24 defining an axial opening or channel (also designated by reference numeral 24) therethrough.

The openings or channels 24 communicate with axially aligned openings defined by the U-shaped inner surface 26 throughout the shaft. The shaft 18 extends axially from a lower annular surface 28 that defines the lower limit of the hub 16 and its flange 22.The U-shaped outer surface of the shaft 18 intersects this surface.

In addition to connecting probe 12 to catheter 2,
Support member 14 provides mechanical and structural support for the remaining members of the invention. Two of these components are a transmitter and a receiver.

In FIG. 1, transmitters are generally designated by the reference numeral 32 and receivers are designated generally by the reference numeral 34. The relationship of these two components is depicted as transmitter 32 being above receiver 34. However, in practice it may also be envisaged that the element 34 operates as a transmitter and the element 32 as a receiver. Since the structure of these two parts of the exemplary embodiment is the same, for convenience the upper one of these parts will be referred to as the transmitter and the lower one as the receiver. It should be understood that this instruction can be reversed and still be within the spirit of the invention. The specific structure of the transmitter of the embodiment depicted in FIGS. 1-3 is best shown in FIG. In this structure, the transmitter 32
includes a piezoceramic transducer 36.

Transducer 36 has an annular configuration and the axial aperture defined by longitudinal surface 38 has a diameter sufficient to allow shaft 18 to pass through the aperture. Transducer 36 has a cylindrical outer surface 40 intersecting axially spaced annular surfaces 42,44 thereof. Transducer 36 is mounted on shaft 18 near the end adjacent hub 16 where outer surface 30 of shaft 18 intersects surface 28 of hub 16 .

Transducer 36 is polarized and plated so that it operates in an axial thickness mode so that the ultrasound signal propagates parallel to the longitudinal axis of probe 12. This may be accomplished by suitably plating the ceramic upper body of the transducer 36, as is well known in the art, such as by silk screen deposition of silver on ceramic or by vacuum deposition of silver on ceramic. carried out by In preferred applications in the planned medical environment,
Transducer 36 has approximately 500 t(z and 2[
In coaxially mounting the transducer 36 on the shaft 18, the transducer 36 is provided in association with a layer 46 of acoustically insulating material that is configured to resonate at a suitable frequency within the IMHz range. The layer 46 has an annular configuration similar to the shape of the transducer 36.
It is positioned or retained between the annular surface 42 of the transducer 36 and the annular surface 28 of the hub 16 of the support member 14. The acoustically insulating material making up layer 46 may be any suitable material known in the art. One example is expandable cell plastic, another example is air space. Generally, this material is
It should be of a type that prevents the acoustic energy generated by the transducer 36 from coupling into the probe support member 14 or the acoustic reflecting means described below. Preventing such coupling increases the performance of transducer 36 and reduces acoustic crosstalk.

The other member shown for use with transducer 36 is a 174 wavelength matching member, also having a ring shape. Member 48 enhances the performance of transducer 36 by increasing the quality factor Q of the resonant circuit of which transducer 36 forms a part, such as plastic or metal, or in other manners known in the art and as described below. An annular laminated member 48, which can be made from any suitable material known in the art for improving the quality of the material, is bonded to the transducer 36 by a suitable material, or otherwise serves as one of the acoustic reflecting means described in more detail below. is supported on an annular surface 50 of the section. More than one matching member can be used here if other similar members described below are used.

The receiver 34 of the embodiment used in FIG.
It is configured in the same way as . In this regard, receiver 34:
A ring-shaped piezoelectric ceramic transducer 52 is provided coaxially mounted on the shaft 18. This places transducer 52 coaxially with transducer 36.

On the other hand, the transducer 52 is disposed proximate the opposite end of the reflective means portion having an end face 50 such that the transducer 52 is longitudinally separated from the transducer 36 by a longitudinal distance d having a specific meaning as hereinafter explained. It is made to be spaced apart.

Similar to transducer 36, transducer 52
associated with an annular layer 54 of acoustic insulating material and an annular 1
A /4 wavelength matching member 56 is disposed and is joined to the transducer 52 and supported adjacent the top surface 58 of the other portion of the acoustic reflecting means illustrated in FIGS. 1-3.

To transmit energizing voltage or current to transmitter transducer 36, the preferred embodiment illustrated in FIG. 2 includes a coaxial wire pair 60 of conductive wires.

1- Receiver transducer 52 includes two coaxial wire pairs 62 for transmitting the voltage or current generated by transducer 52 in response to the ultrasonic signal obtained as a reflection of the ultrasonic signal generated by transducer 36; conductive wires are connected. The two conductive wires of the coaxial wire pair 60 are connected to both sides of the transducer 3G across the axial thickness of the transducer 3G. That is, one conductive wire is connected to the surface 42 of the transducer 36 and the other conductive wire is connected to the surface 44. These connections are made such that the radial extensions 64,66 of the conductive wires extend through substantially the same diametric plane. This is best shown in FIG. 3, which shows the radial portions 68,70 of the conductive wires of the coaxial wire pair 62. These conductive wire pairs are then connected to receiver transducer 52. As depicted in FIG. 3, the radial extensions 68,70 are not exactly in the same diametric plane, but are intended to be offset by a few degrees as shown. This structure facilitates threading the wire through an axial channel extending through the support member.

In the embodiment of FIG. 2, if transducer 36 is described as a transmitter and transducer 52 as a receiver, then the conductor of wire pair 60? The i-line is used to activate the transducer 36 to propagate a continuous wave acoustic signal. The continuous wave acoustic signal is transmitted to the shaft 1 of the support member 14 due to the structure and structural positioning of the transducer 36.
A continuous wave acoustic signal is propagated parallel to 8. According to this assignment of transmit and receive instructions, transducer 52 generates an electrical signal in response to the reflection of a continuous wave acoustic signal reflected from an acoustic reflector external to probe 12 (e.g., descending aortic blood flow) and received by transducer 52. The conductive wires of wire pair 62 are connected to transmit signals.

The acoustic reflecting means of the embodiment illustrated in FIG. The reflective member 72 is provided in conjunction with the receiver 34. The reflective member 72 is formed of any acoustic energy reflective material known in the art, such as aluminum or plastic. , probe 1
2, the reflective member 74 reflects external acoustic energy in a path having an operating angle that is relative to the longitudinal axis of the probe 12 in the preferred embodiment. An acoustic reflected wave is received from the reflector and reflected towards the receiver 34.

Reflective member 72 is mounted coaxially on shaft 18 and coaxially with respect to transducer 36.52. The reflective member 72 has an annular surface at its upper end, near the transducer 36, and specifically adjacent the lower surface of the 174 wavelength matching member 48. From the outer periphery of the surface 50,
A cylindrical surface 76 extends, and the surface 50 and a portion of the cylindrical inner surface 78 together define a cylindrical neck of the reflective member 72. The surface 78 extends along the length of the frustoconical portion of the reflective member 72. The outer surface of the 0-truncated conical section, which is coaxial with the directional center, is defined by an outer sloped surface 80. The surface 80 is
The transducer 36 is positioned such that when the transducer 36 is actuated, a continuous wave acoustic signal propagated from the transducer is reflected along a circumferential or omnidirectional transmission reflection path that is inclined with respect to the shaft 18. This transmission-reflection path, or beam pattern, extends around the entire circumference of probe 12, as indicated by arrow 82 in two dimensions in FIG. These arrows 82 depict that the 360 degree beam pattern forms an angle of inclination with respect to the longitudinal axis of the probe 12. However, the angle of the lever is the operating angle described above. Second
In the illustrated embodiment, this angle is downwardly acute and is set so that the arrow 82 points downwardly and laterally away from the probe 12. In a preferred embodiment,
This angle is about 45'' and is obtained by forming surface 80 at an angle of about 22.5° with respect to the longitudinal axis of reflective member 72 (and thus with respect to the longitudinal axis of probe 12).

Reflective member 72 terminates at its lower end in an annular surface 84 and has transducer 5 adjacent to the surface.
A layer 54 of acoustic insulating material associated with 2 is disposed.

In the illustrated preferred embodiment, reflective member 74 is constructed similarly to reflective member 72. Reflection member 74
is located below the transducer 52 (therefore on the opposite side of the transducer 52 from the reflective member 72),
For example, a reflection of a continuous wave acoustic signal reflected from an external acoustic reflector outside the esophagus is reflected by the sloped surface 86 of the member 74 to form a further reflection, and the transuser 5
2 responds to this. In an exemplary preferred embodiment,
The angle of inclination at which the surface 86 is located is equal to the angle of the surface 80 (i.e. (1/2)). Even if the angle at which the surface 80.86 is located has some small deviation from the equal angle, the present invention Note that can accommodate this deviation. However, it is important to note that the angles of these surfaces with respect to the longitudinal axis are always at least substantially equal, with only a variation of a few degrees allowed, thereby obtaining the advantages of the relatively simple and economical construction of the present invention. is an important feature of the invention.

Because the angles of the surfaces 80.86 are substantially equal (including equal angles and some deviations therefrom), and because the acoustic reflective members 72.74 are mounted coaxially on the shaft 18, the shaft 18 is Because they extend through the axial opening of the member, the external sloped surfaces 80.86 may be said to be substantially parallel. Therefore, the incoming reflected wave received in the receive reflection path indicated by arrow 88 is substantially parallel to the transmitted ultrasound signal propagated and reflected in the path represented by arrow 82. When the surfaces 80,86 are to be configured to be truly parallel as illustrated in FIG. , so that true and exact parallelism can be maintained despite the longitudinal spacing between the surfaces 80,86.

The amount of deviation from such exact parallelism that can be adjusted in the present invention, e.g., to adjust the focus of the transmit and receive beam patterns, and thus the term substantially parallel as used herein to include exact parallel and such deviations. The limit for J is based on the following equation derived from the law of cosines.

where ° is the desired or nominal basic operating angle as previously defined, d is the previously defined axial spacing (in millimeters) between the corresponding faces of the transducer 36.52, and Z is the desired or nominal basic operating angle to be detected by the reflected acoustic signal. The distance (in millimeters,
(measured from the midpoint of d to the target). The angle represents the maximum deviation from true parallelism between the resulting transmit and receive steering angles. These obtained operating angles are such that the maximum deflection from true parallelism between surfaces 80.86 is (1/2) ()
This can be obtained by configuring one or both of the following. For example, for a nominal operating angle = 45' and appropriate dimensions for d and Z, the angle is approximately 14°. therefore,
Surfaces 80.86 alter the inclination of surface 80 by approximately 3.5° in one direction with respect to the longitudinal axis of probe 12 and the inclination angle of surface 86 by approximately 3.5° in the other direction with respect to the longitudinal axis of probe 12. They may be configured to be offset from each other by about 7°, as can be done by varying the angle.

The embodiment shown in FIG. 2 also includes a suitable acoustically insulating material [90] adjacent the lower annular surface 92 of the reflective member 74. The N90 is used at the bottom of the illustrated assembly to prevent acoustic energy from being transmitted in a direction parallel to the longitudinal axis of the probe 12.

To protect the internal components and facilitate insertion of the probe 12 into the esophagus, a relatively thin, elongated sleeve of a suitable flexible plastic is provided over the transmitter 32, receiver 34,
reflective elements 72, 74, various layers of acoustically insulating material and l
/4 wavelength matching member is accommodated. Sleeve 94 also forms a sheath or casing to improve the efficiency of transmission of acoustic energy in cavity 96.98 defined between reflective member 73.74 and the facing portions of the inner surface of sleeve 94. In preferred embodiments, the liquid is any suitable water-based or oil-based liquid that conducts ultrasound energy with minimal distortion and attenuation. Sleeve 94 is attached to tubular catheter member 4 by any suitable thermoplastic bonding technique.6 As shown in FIG.
The second end engages or connects with the cylindrical outer surface.

Another embodiment of the invention is partially shown in FIG. 6, which is identical to the embodiment shown in FIG. 1 except for the specific shapes of the two reflective members. It is. In the embodiment of FIG. 6, the reflective member 100 has an inclined surface 102 defined by an angle 103 of approximately 67.5 degrees,
02 such that the omnidirectional transmission reflection path defined by axially parallel propagation extends at an upward angle of about 45° with respect to the longitudinal axis of the probe embodiment shown in FIG. being done. This omnidirectional transmission reflection path is identified in two dimensions in FIG. 6 by arrow 104. Reflective member 100 is distinguished from corresponding reflective member 72 in the embodiment of FIG. 2 by having a long neck. The particular length of this long neck ensures that this transmission-reflection path prevents a significant portion of the propagating ultrasound energy from being reflected toward the transducer 36 within the containment boundaries of the probe depicted in FIG. is selected such that it is reflected out of the probe 12. Reflective member 1
06 is configured identically to reflective member 100 (or within the zero-based deflection defined above), but with a longitudinal axis from reflective member 100 for use with receiver transducer 52 of the embodiment of FIG. are spaced downwardly.

The embodiment of the invention shown in FIG. 4 has several elements similar to those shown in FIG. 2, as indicated by the same reference numerals. However, the embodiment of FIG. 4 has only a single reflective member 108, which is identical to either of the reflective members 72, 74 shown in FIG. In the embodiment of FIG. 4, only one reflective member 108 is required. This is because this member provides the same reflective surface for both the transmit reflection path and the receive reflection path, and therefore the reflection member 108
This is because the sloped surface of reflects the transmitted and received acoustic signals along the same reflection angle. The transmitter and receiver of the embodiment of FIG. 4 consists of two concentrically arranged transistors 1-110.
As in the embodiment described above, only one reflective surface is required because the transducer 110 is formed by the transmitter 112. can be used as either a receiver or a transmitter. transducer 110
．． To acoustically insulate 112, the embodiment of FIG. 4 includes an annular layer 114 of acoustically insulating material circumferentially between transducers 110, 112. layer 11
4 is also located between two concentrically related 174 wavelength matching members 116.118 each attached to a transducer 110.112. Although the embodiment of FIG. 5 is constructed substantially identically to the embodiment shown in FIG. 4, the embodiment of FIG. A single reflecting member 120 having a - shape is combined.

Any of the embodiments shown in FIGS. 4-6 can be used in place of the particular embodiment shown in FIG. 1 by attaching it to catheter 2 as probe 12.

In addition, the transformer 1 of each embodiment shown in FIGS.
- the conductive wire is suitably connected to a conductive wire, which is connected to an electrical circuit outside the catheter 2, as is well known in the art and as for the embodiments of FIGS. It turns out.

[In operation, the selected embodiment attaches to the end of the catheter 2 by inserting the hub of the probe into the distal end of the tubular member 4 and joining the sleeve of the probe with the outer surface of the tubular member 4. The assembly is then lowered into the esophagus (a particular example) in a conventional manner, and the conductive wires extending from the probe and out of the catheter are connected to appropriate circuitry to transmit ultrasound signals from the transmitting transducer. An example of this type of circuit is disclosed in U.S. Pat. No. 993. In a preferred embodiment, continuous wave ultrasound transmission is performed continuously throughout the time a test is being performed, such as monitoring of migrating blood cells, thereby providing constant monitoring. shall be carried out.

Once the catheter/probe assembly is so installed and connected, it transmits, receives, and analyzes ultrasound signals according to the Doppler effect within a few centimeters of the esophagus in which the catheter/probe is placed, as an exemplary environment. This distance is approximately 20 to 40 millimeters in humans, allowing us to determine the velocity of external acoustic reflectors of targets such as blood flow flowing in descending arteries located at 6.

This distance, in this particular example, defines the range Z mentioned above in connection with the parallel angles associated with the embodiments shown in FIGS. 2 and 6.

[Respectfully] Figure 1 is an upright elevational view of the device of the present invention, which is an embodiment of an esophageal Doppler probe, with the lower part cut away to schematically show the embodiment of the probe. A cross-sectional view of the lower end of the probe and catheter taken along the longitudinal axis at the lower end of the assembly illustrated in FIG.
A cross-sectional view of the device taken along line 3-3 shown in the figure;
4 is a cross-sectional view similar to that shown in FIG. 2, showing another embodiment of the invention; and FIG. 5 is a cross-sectional view similar to that shown in FIGS. 2 and 4. FIG. 6 is a sectional view similar to that shown in FIGS. 2.4 and 5, showing a further embodiment of the invention. 2: Catheter 4: ring member 6: perforation 8 sleeve 10: adapter 12 nib lobe 14: support member 16: hub 18: shaft 22: peripheral flange 32: transmitter 34: receiver 36: piezoelectric ceramic transducer 46: acoustic insulating material layer 48 : Matching member 52: Piezoelectric ceramic transducer 54, acoustic insulating material layer 56: Matching member 60: Conductive wire 80.86: Slanted surface

Claims (14)

[Claims] (1) In a device that is attached to the end of a hollow catheter and removably inserted into the esophagus for use in detecting the velocity of an acoustic reflector target by the Doppler effect, a hub for connection with the hollow catheter; a support means having a shaft extending axially from the hub; a first piezoelectric transducer mounted on an end of the shaft adjacent the hub; a first acoustic reflective member mounted proximate a piezoelectric transducer; a second piezoelectric transducer mounted on the shaft proximate a second end of the first acoustic reflective member; and a second piezoelectric transducer mounted on the shaft proximate a second end of the first acoustic reflective member; the second piezoelectric transducer is connected to the first piezoelectric transducer;
an acoustically reflective member and a second acoustically reflective member mounted between the second acoustically reflective members, each acoustically reflective member having a cylindrical neck having a cylindrical inner surface defining an axial opening; a frustoconical portion having a cylindrical inner surface and a sloped outer surface defining an axial opening extending in axial alignment with the axial opening passing through the cylindrical neck, the shaft extending along the axis of the reflective member; the first and second acoustic reflective members are coaxially mounted on the shaft of the support member such that the directional opening extends through the directional opening and the sloped outer surfaces of the frustoconical portion of the reflective member are parallel; A detection device characterized by: (2) a first layer of acoustic insulating material disposed between the hub and the first piezoelectric transducer; and a first quarter-wavelength matching disposed between the first piezoelectric transducer and the first acoustic reflective member. a second acoustically insulating material layer disposed between the first acoustically reflective member and the second piezoelectric transducer; and a second layer of acoustically insulating material disposed between the second piezoelectric transducer and the second acoustically reflective member.
/4 wavelength matching member and the second acoustic reflecting member.
2. A detection device as claimed in claim 1, comprising a third layer of acoustically insulating material located at an end opposite the piezoelectric transducer. (3) the hub and the shaft have an axial opening therethrough; and a first piezoelectric transducer connected to the first piezoelectric transducer and extending through the axial opening of the hub and the shaft. a pair of conductive wires connected to the second piezoelectric transducer;
a second pair of electrically conductive wires extending through axial openings of the hub and the shaft;
A selected one of the piezoelectric transducers is actuated to propagate a continuous wave acoustic signal parallel to the shaft of the support member, the other of the first and second piezoelectric transducers being reflected from an acoustic reflector target. 2. The detection device of claim 1, wherein the detection device is configured to transmit an electrical signal through a corresponding pair of conductive wires in response to the continuous wave acoustic signal. (4) a casing connected to the hub and extending around the first and second piezoelectric transducers and the first and second acoustic reflecting members; 2. The detection device according to claim 1, wherein a cavity is formed between said cavity and a liquid for improving the efficiency of transmission of acoustic energy in said cavity. (5) a transmitter for transmitting an ultrasound signal into the body of an animal; a receiver for receiving a reflection of the ultrasound signal reflected from an acoustic reflector of the body; and a receiver connected to the transmitter; a first acoustic reflective member having a first surface for reflecting the ultrasound signal from the transmitter into the body; and a first acoustic reflecting member connected to the receiver to reflect the ultrasound signal from the body acoustic reflector. a second reflecting signal to the receiver;
a second acoustic reflecting member having a surface of
An ultrasound probe for use within an animal body, wherein the second acoustic reflective member is arranged with respect to the first acoustic reflective member such that the surface and the second surface are substantially parallel. . (6) The ultrasonic probe according to claim 5, wherein the first surface is an inclined outer surface of a first truncated cone portion, and the second surface is an inclined outer surface of a second truncated cone portion. . (7) The first truncated conical portion has a longitudinal central axis, and further comprises means for supporting the second truncated conical portion coaxially with the longitudinal central axis of the truncated conical portion. The ultrasonic probe according to item 6. (8) The first acoustic reflecting member includes a first cylindrical neck extending from the end of the first truncated cone, and the second acoustic reflecting member extends from the end of the second truncated cone. 7. The probe of claim 6, comprising a second cylindrical neck. (9) the first acoustic reflective member has a central longitudinal axis such that the first surface reflects the ultrasound signal at a nominal operating angle (°) with respect to the central longitudinal axis; the first surface of the reflective member is oriented such that the transmitter and receiver have corresponding surfaces axially spaced apart with respect to the central longitudinal axis by a distance of d millimeters; said substantially parallel first and second surfaces having a midpoint located between the transmitter and the receiver and spaced from the acoustic reflector of the body by a distance of z millimeters when the probe is placed within the body; is within the parallel range between 0 deflection from true parallelism and a deflection of (1/2) ( )° from true parallelism, where ▲There are mathematical formulas, chemical formulas, tables, etc.▼, of the patent claim. Ultrasonic probe according to scope 5 (10) an elongate support member having a central longitudinal axis;
a ring-shaped first tone juicer having a hole through which the supporting member passes; and a first acoustic reflecting member having a first truncated cone portion through which the supporting member passes; one frustoconical section has an outer surface defined by an inclined outer surface oriented at a first angle with respect to the central longitudinal axis, thereby providing a nominal operating angle (
°), and further comprising a hole therethrough, the support member having a hole therethrough such that there is a distance of d millimeters between corresponding positions of the first transducer and the second transducer. a second acoustically reflective member having an attached annular second transducer and a second truncated conical portion through which the support member passes; the second truncated conical portion of the second acoustic reflective member; an outer surface defined by an inclined outer surface oriented at a second angle with respect to the central longitudinal axis, wherein the difference between the first and second angles is not greater than (1/2)( )°; , ▲ Mathematical formulas, chemical formulas, tables, etc. ▼ where z = distance (in millimeters) that the acoustic reflector target of the animal's body is spaced from the midpoint of the distance d between said first and second transducers; An ultrasonic probe for use inside an animal body, characterized by: (11) The first acoustic reflecting member further includes a first cylindrical neck extending from the end of the first truncated cone toward the first transducer, and the second acoustic reflecting member further includes 11. The ultrasound probe of claim 10, further comprising a second cylindrical neck extending from an end of the frustoconical portion toward the second transducer. (12) an elongated support member having a central longitudinal axis;
a ring-shaped first concentric transducer mounted about the support member coaxially with the longitudinal central axis; and about the first transducer coaxially with the longitudinal central axis; and the first
a pair of concentric transducers including a ring-shaped second transducer mounted concentrically within the second transducer and mounted on the support member coaxially with the longitudinal central axis; and a single acoustic reflective member having a single beveled outer surface extending around the central longitudinal axis and extending in an oblique direction with respect to the central longitudinal axis. 13. The ultrasound probe of claim 12, wherein said single acoustic reflective member further comprises a cylindrical neck extending from an end of said sloped outer surface toward said pair of concentric transducers. (14) the support member comprises a shaft to which the pair of concentric transducers and a single acoustic reflective member are attached; and a hub having an annular surface extending from the shaft; a first layer of acoustically insulating material disposed between an annular surface and both the first and second transducers and about the shaft of the support member adjacent the first transducer;
and a first quarter-wavelength matching member disposed such that the first transducer is between the first matching member and the first layer of acoustic insulating material; and a first quarter-wavelength matching member adjacent the second transducer; 1 alignment member, such that the second transducer resides between the second alignment member and the first layer of acoustic insulation material, and such that the first alignment member is concentric with the alignment member. Second 1/ placed
Claim 12, comprising a four-wavelength matching member and a second layer of acoustically insulating material disposed between the first and second transducers and between the first and second matching member.
Ultrasonic probe as described in section.