Ultrasound Mammography Patents (Class 128/915)
  • Patent number: 6728394
    Abstract: Method of dynamically measuring movement of objects is disclosed which uses image processing. In a first step a sequence of images is received and stored. Then, at least a first and second reference point within a first image is determined and identification areas around those reference points are defined. Within a sequential image a search area around the predefined reference points which best match the identification area is searched to determine the displacement of the reference point.
    Type: Grant
    Filed: February 14, 2000
    Date of Patent: April 27, 2004
    Assignee: Siemens Medical Solutions USA, Inc.
    Inventors: Jian-Feng Chen, Jin Kim
  • Patent number: 6704438
    Abstract: A parallel, frequency domain filter (50) for providing frequency-dependent phase delay for real data includes a fast Fourier transform (FFT) device (52), a complex multiplier (54), a filter memory (56) and an inverse fast Fourier transform (IFFT) device (58). The FFT and IFFT devices (52) and (58) are shown with two inputs and two outputs each. The filter (50) of the present invention allows for increased throughput by filtering two real signals in parallel, one being applied to the real input of FFT device (52) and the other being applied to the imaginary input of FFT device (52). The filter memory 56 of FIG. 2 is provided with sufficient capacity to store several filter frequency characteristics. The appropriate filter frequency characteristic for the particular digitized rf signal being processed can be selected based on factors such as beam focus depth. The parallel, frequency domain filter (50) allows the use of coded waveforms to improve signal to noise ratio in ultrasound images.
    Type: Grant
    Filed: May 8, 2000
    Date of Patent: March 9, 2004
    Assignee: Aloka Co., Ltd.
    Inventor: Radu Alexandru
  • Patent number: 6701341
    Abstract: An ultrasound information processing system is disclosed in which ultrasound image data is packetized into ultrasound information packets and routed to one or more of a plurality of processors for performing image processing operations on the ultrasound image data, the ultrasound information packets being routed according to entries in a host-programmable routing table. A common distribution bus is coupled between packetizing circuitry and dedicated input buffers corresponding to each processor for distributing the ultrasound information packets, and a common output bus to is used to transfer processed image data from the processors to an output device. The disclosed ultrasound information processing system architecture allows for a high throughput rate for accommodating real-time image processing operations, while also allowing for ready programmability and upgradability.
    Type: Grant
    Filed: November 24, 1999
    Date of Patent: March 2, 2004
    Assignee: U-Systems, Inc.
    Inventors: Anthony Wu, Shengtz Lin, Ali Moayer, Pin Yu
  • Patent number: 6687392
    Abstract: A system for analyzing an echo image containing a contour of an organ with reduced manual operation is provided. The echo image is first obtained. A user manually sets, say, four points as known or initial points such that two of the known points provide a width of the contour and the other two of the known points provide a height of the contour. A search region including a connecting line segment connecting each pair of adjacent ones of the known points is set on the contour. A search line segment that originates from a point bisecting the connecting line segment of the search region and reaches an end of the search region is set. Each search line segment is sought for a contour point constituting the contour. A contour is formed by connecting the contour points on the search line segments. Three points may be set as the initial points such that two of the initial points provide a width of the contour and the other one is on top of the contour.
    Type: Grant
    Filed: September 29, 1999
    Date of Patent: February 3, 2004
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Yoshito Touzawa, Morio Nishigaki, Hisashi Hagiwara
  • Patent number: 6641537
    Abstract: An ultrasonic transmission unit for an imaging/quantitative ultrasound device provides for coaxial transducer crystals which may be operated independently with a first crystal operated alone for quantitative measurement and the first and second crystal operated together to provide a broad illumination for imaging of structure.
    Type: Grant
    Filed: July 20, 2001
    Date of Patent: November 4, 2003
    Assignee: GE Medical Systems Global Technology Company, LLC
    Inventors: Richard Franklin Morris, Steven Taylor Morris, Duane Anthony Kaufman
  • Patent number: 6614921
    Abstract: A method using CC and MLO views localized in a display in 3-D as a breast virtual model, incorporating, feature capturing using gradient, energy and entropy codes, calibration classification according to features using binary decision trees, nipple detection, and 3-D spatial coordinate transformation and display of breast clustered microcalcifications.
    Type: Grant
    Filed: April 20, 2000
    Date of Patent: September 2, 2003
    Assignee: National Science Council
    Inventors: Pau-Choo Chung, Chien-Shun Lo, Chein-I Chang, San-Kan Lee, Ching-Wen Yang
  • Patent number: 6574499
    Abstract: A system for generating a three-dimensional image of the compressed breast 40 of a subject includes an x-ray mammography unit 24 for generating x-ray mammography data, a mechanical scanner 20 including an x-ray mammography compression paddle assembly 22, a control and motion system 26, 28 for driving the mechanical scanner 20 and for sensing the control and motion system's position, an ultrasound probe 32 for generating ultrasound image data in spatial registration with the x-ray mammography unit 24, and a computer 38 for generating from the ultrasound image data and the x-ray mammography data the three-dimensional ultrasound image.
    Type: Grant
    Filed: November 24, 1999
    Date of Patent: June 3, 2003
    Assignee: Xdata Corporation
    Inventors: Kris A. Dines, Elizabeth Kelly-Fry, Ada Patricia Romilly
  • Patent number: 6482158
    Abstract: A system for ultrasonic mammography includes an ultrasonic mammography device for constructing an ultrasonic image of a breast having a support structure with an ultrasonic transducer mounted on the support structure. The system also includes a personal digital assistant operatively connected to the ultrasonic transducer via a communication link, a patient computer system operatively connected to the personal digital assistant via a second communication link, and a healthcare provider computer system operatively connected to the patient computer system via an internet, for constructing the image of the breast. The method includes the steps of positioning the ultrasonic mammography device having an ultrasonic transducer on the patient and activating the ultrasonic transducer to generate a signal for constructing an image of the breast.
    Type: Grant
    Filed: May 14, 2001
    Date of Patent: November 19, 2002
    Assignee: Healthetech, Inc.
    Inventor: James R. Mault
  • Patent number: 6478739
    Abstract: A wearable breast tissue examination device including a support element adapted to fit over at least a portion of a breast of the wearer. The support element has a shell, a measurement apparatus including at least two mutually opposed ultrasound transducer arrays disposed on at least a portion of the inner surface of the shell and at least one bladder element disposed in the shell that is configured to orient the wearer's breast properly for examination. The wearable device may also include means for operatively connecting the two mutually opposed transducer arrays to a transducer driver, and means for holding the support element on the wearer during use.
    Type: Grant
    Filed: May 11, 2001
    Date of Patent: November 12, 2002
    Assignee: The Procter & Gamble Company
    Inventor: Hyundae Hong
  • Patent number: 6459925
    Abstract: The present invention provides for x-ray imaging and ultrasound imaging of a body region of interest in a spatially correlatable manner. The resultant x-ray and ultrasound images may be combinatively employed to provide three-dimensional information regarding a location of interest within the body, and is particularly apt for use in the analysis/biopsy of potential lesions and suspicious masses in a female breast. The invention provides for direct body contact by an ultrasound imaging head, as well as targeted ultrasound imaging of a selected portion of the region from which x-ray images are obtained. A user interface system facilitates various procedures including ultrasound guided needle biopsy procedures.
    Type: Grant
    Filed: November 24, 1999
    Date of Patent: October 1, 2002
    Assignee: Fischer Imaging Corporation
    Inventors: Morgan W. Nields, John Connor, Curtis Daly
  • Patent number: 6254538
    Abstract: A system and process are provided for performing percutaneous biopsy within a breast using three-dimension ultrasonography and including a breast positioning device, a breast immobilization device, an ultrasonic imaging device, a biopsy instrument positioning device, the breast immobilization device and the three-dimensional ultrasonographic imaging device being positioned in a known relationship to each other, the breast immobilization device being employed to immobilize the breast and a lesion contained therein for imaging by the three-dimensional ultrasonic imaging device, and the three-dimensional ultrasonic imaging device being employed to assist an operator in positioning the biopsy instrument positioning device relative to the lesion and guiding a biopsy instrument percutaneously to the lesion.
    Type: Grant
    Filed: April 29, 1999
    Date of Patent: July 3, 2001
    Assignee: Life Imaging Systems, Inc.
    Inventors: Donal B. Downey, Aaron Fenster
  • Patent number: 6216025
    Abstract: Methods and apparatus for measuring and characterizing the localized electromagnetic wave absorption properties of biologic tissues in vivo, using incident electromagnetic waves to produce resultant acoustic waves. Multiple acoustic transducers arranged on an rotatable imaging bowl are acoustically coupled to the surface of the tissue for measuring acoustic waves produced in the tissue when the tissue is exposed to a pulse of electromagnetic radiation. The multiple transducer signals are then combined to produce an image of the absorptivity of the tissue, which image may be used for medical diagnostic purposes. Specific mathematical reconstruction procedures are described for producing images from transducer signals. Specific arrangements of transducers are illustrated, and noise reduction techniques are described.
    Type: Grant
    Filed: February 2, 1999
    Date of Patent: April 10, 2001
    Assignee: Optosonics, Inc.
    Inventor: Robert A. Kruger
  • Patent number: 6122542
    Abstract: A breast stabilization device for imaging and invasive medical procedures includes a shell configured to surround a superior portion of a breast when the breast rests on a substantially flat surface. The shell includes a first opening configured to allow at least a portion of a nipple-areolar complex of the breast to protrude therethrough. A first and second flange extend from the shell to secure the shell to the flat surface. A third flange may also be included to secure the shell to the patient's chest wall. The shell includes a substantially rigid outer member and a relatively softer inner member that is in contact with the patient's breast when the device is in use. The substantially rigid outer member includes a suction port and the relatively softer inner member includes a through holes in fluid communication with the suction port, to allow a patient's breast to be drawn toward the inner member when fluid is drawn from the suction port.
    Type: Grant
    Filed: November 25, 1998
    Date of Patent: September 19, 2000
    Assignee: Rubicor Medical, Inc.
    Inventors: Roberta Lee, James W. Vetter, Natalie N. Hyland
  • Patent number: 6102866
    Abstract: The present invention provides for x-ray imaging and ultrasound imaging of a body region of interest in a spatially correlatable manner. The resultant x-ray and ultrasound images may be combinatively employed to provide three-dimensional information regarding a location of interest within the body, and is particularly apt for use in the analysis/biopsy of potential lesions and suspicious masses in a female breast. The invention provides for direct body contact by an ultrasound imaging head, as well as targeted ultrasound imaging of a selected portion of the region from which x-ray images are obtained.
    Type: Grant
    Filed: July 6, 1998
    Date of Patent: August 15, 2000
    Assignee: Fischer Imaging Corporation
    Inventors: Morgan W. Nields, Bogdan R. Ulatowski
  • Patent number: 6056696
    Abstract: A frustrated total internal reflection acoustic field sensor which allows the acquisition of the acoustic field over an entire plane, all at once. The sensor finds use in acoustic holography and acoustic diffraction tomography. For example, the sensor may be produced by a transparent plate with transparent support members tall enough to support one or more flexible membranes at an appropriate height for frustrated total internal reflection to occur. An acoustic wave causes the membrane to deflect away from its quiescent position and thus changes the amount of light that tunnels through the gap formed by the support members and into the membrane, and so changes the amount of light reflected by the membrane. The sensor(s) is illuminated by a uniform tight field, and the reflection from the sensor yields acoustic wave amplitude and phase information which can be picked up electronically or otherwise.
    Type: Grant
    Filed: September 4, 1998
    Date of Patent: May 2, 2000
    Assignee: The Regents of the University of California
    Inventor: Jeffrey S. Kallman
  • Patent number: 5979457
    Abstract: "Methods and apparatus for producing enhanced ultrasound images of portions of the human body while utilizing the beneficial effects of floatation are disclosed." Although the method is especially useful for generating images of the female breast, tissues of the male abdomen and testicles may also be imaged using the present invention. In the preferred embodiment of the invention, a patient relaxes while substantially immersed in hot water. When the breast is submerged, the buoyancy of the breast tissue in the water counteracts the effects of gravity. The buoyancy of the water enhances the capacity of an ultrasound sensor which is also submerged to form an image of the body tissues which may be employed to detect abnormalities.
    Type: Grant
    Filed: November 7, 1996
    Date of Patent: November 9, 1999
    Inventor: Roderick G. Rohrberg
  • Patent number: 5983123
    Abstract: Apparatus is provided that combines radiography equipment with an ultrasonic transducer to generate ultrasonic images of the internal structure of biological tissue that are in registration with an X-ray image. The apparatus includes an examination table having a radiolucent and sonolucent window for imaging the biological tissue with an ultrasound and X-ray subsystems without moving the patient. In alternative embodiments, the ultrasound transducer may be an annular array transducer mounted on a moveable or a linear array of ultrasonic transducing elements. The X-ray images are preferably generated digitally using a line X-ray source and detector.
    Type: Grant
    Filed: June 18, 1998
    Date of Patent: November 9, 1999
    Assignee: United States Surgical Corporation
    Inventor: Ascher Shmulewitz
  • Patent number: 5938613
    Abstract: Apparatus is provided that combines mammography equipment with an ultrasonic transducer to generate ultrasonic images of the internal structure of breast tissue that are in geometric registration with a mammogram. The apparatus includes a radiolucent and sonolucent compression plate, and in alternative embodiments, a gantry driven ultrasound transducer or a phased array ultrasonic transducer. Methods are provided for generating a mammogram and a plurality of corresponding ultrasound images without moving the breast between the mammogram exposure and the ultrasound imaging. Methods are also provided for viewing and analyzing the ultrasound images. Apparatus and methods are also provided for enhancing X-ray images obtained from conventional mammographic systems, and with reduced overall X-ray dosage to the patient.
    Type: Grant
    Filed: April 11, 1997
    Date of Patent: August 17, 1999
    Assignee: United States Surgical Corporation
    Inventor: Ascher Shmulewitz
  • Patent number: 5840022
    Abstract: In a method and apparatus for displaying an image, particularly of the female mammary gland, obtained from echo signals produced by ultrasound radiation directed onto the subject, the evaluation of echo signals time-dependently received by an echo signal receiver ensues on a subject axis directed in the spatial direction of the primary radiation and the intensity of the echo signals is evaluated. In the imaging evaluation, the echo signal is combined in a corresponding spatial reference orientation with a further imaging signal of a different signal source registered in the corresponding spatial direction with the subject held fixed in the same position as for producing the echo signals. The further imaging signal by itself, or in combination with the echo signals, provides diagnostic information not available from the echo signals by themselves. In the case of the female mammary gland, the mammary gland is fixed between two plates directed essentially parallel.
    Type: Grant
    Filed: September 22, 1995
    Date of Patent: November 24, 1998
    Assignee: Siemens Aktiengesellschaft
    Inventor: Kari Richter
  • Patent number: 5833627
    Abstract: Apparatus and methods are provided for positioning a needle or cannula of a biopsy device for insertion into a tissue mass by correlating, in real-time, the actual needle or cannula position prior to insertion with its probable trajectory once inserted. In a preferred embodiment, a biopsy device support block is mechanically coupled to an ultrasound transducer to provide alignment of the biopsy device with the ultrasound image in at least one plane. Continued ultrasound scanning of a selected trajectory may be provided to assess depth of penetration of the needle or cannula of the biopsy device, when inserted.
    Type: Grant
    Filed: July 12, 1996
    Date of Patent: November 10, 1998
    Assignee: United States Surgical Corporation
    Inventors: Ascher Shmulewitz, Edo Ziring
  • Patent number: 5820552
    Abstract: Apparatus for conducting an imaging examination and/or biopsy of biological tissue that enable a patient to remain in an inclined, seated orientation, so that the tissue is readily presented for examination and biopsy, while the examination and biopsy site is screened from the patient's view. Apparatus also provided for enhancing imaging of the patient's tissue near the chest wall, and for conducting image-guided biopsy.
    Type: Grant
    Filed: July 12, 1996
    Date of Patent: October 13, 1998
    Assignee: United States Surgical Corporation
    Inventors: Peter Andrew Crosby, Ascher Shmulewitz
  • Patent number: 5776062
    Abstract: The present invention provides for x-ray imaging and ultrasound imaging of a body region of interest in a spatially correlatable manner. The resultant x-ray and ultrasound images may be combinatively employed to provide three-dimensional information regarding a location of interest within the body, and is particularly apt for use in the analysis/biopsy of potential lesions and suspicious masses in a female breast. The invention provides for direct body contact by an ultrasound imaging head, as well as targeted ultrasound imaging of a selected portion of the region from which x-ray images are obtained.
    Type: Grant
    Filed: October 15, 1996
    Date of Patent: July 7, 1998
    Assignee: Fischer Imaging Corporation
    Inventor: Morgan W. Nields
  • Patent number: 5709206
    Abstract: The present invention relates to a method and an apparatus for processing a plurality of ultrasound images of ductolobular systems in a breast. The operator scans each particular duct system in the breast and saves these axial scan segments. Further, the operator scans the ductolobular systems transaxially. The imaging system, interactively with the operator, aligns the axial scan segments of the duct. This is accomplished by electronically noting the radial direction of the axial scan or by identifying two like image points on respective, sequential axial scan segments. A composite axial scan image in compiled by aligning multiple, sequential axial scan segments together. The associated transductal scan images are mapped to the axial scan segment. The composite axial scan image is displayed with a clockface template of the breast, a vertical, cross-section template of the breast and a three dimensional composite image of the breast.
    Type: Grant
    Filed: November 27, 1995
    Date of Patent: January 20, 1998
    Inventor: Michel Teboul
  • Patent number: 5664573
    Abstract: Apparatus is provided that combines mammography equipment with an ultrasonic transducer to generate ultrasonic images of the internal structure of breast tissue that are in geometric registration with a mammogram. The apparatus includes a radiolucent and sonolucent compression plate, and in alternative embodiments, a gantry driven ultrasound transducer or a phased array ultrasonic transducer. Methods are provided for generating a mammogram and a plurality of corresponding ultrasound images without moving the breast between the mammogram exposure and the ultrasound imaging. Methods are also provided for viewing and analyzing the ultrasound images. Apparatus and methods are also provided for enhancing X-ray images obtained from conventional mammographic systems, and with reduced overall X-ray dosage to the patient.
    Type: Grant
    Filed: November 16, 1995
    Date of Patent: September 9, 1997
    Assignee: Neovision Corporation
    Inventor: Ascher Shmulewitz
  • Patent number: 5487387
    Abstract: A method and apparatus for distinguishing between solid masses and fluid-filled cysts by using an ultrasonic transducer to transmit a plurality of ultrasonic signals into a target lesion within a human body and for receiving a plurality of reflected signals therefrom. At least one of the plurality of transmitting signals should be of sufficient intensity to initiate movement of any fluid located within the target lesion. A plurality of reflected ultrasonic signals are received from the target lesion and a comparison of differences between individual ones of the plurality of reflected signals is made to detect the presence or absence of fluid movement within the target lesion. Then a determination is made as to whether the target lesion is a fluid-filled cyst or a solid mass based upon the presence or absence of fluid within the target lesion.
    Type: Grant
    Filed: June 3, 1994
    Date of Patent: January 30, 1996
    Assignee: Duke University
    Inventors: Gregg E. Trahey, Phyllis Kornguth, Kathryn Nightingale, William F. Walker
  • Patent number: 5479927
    Abstract: Apparatus is provided that combines mammography equipment with an ultrasonic transducer to generate ultrasonic images of the internal structure of breast tissue that are in geometric registration with a mammogram. The apparatus includes a radiolucent and sonolucent compression plate, and in alternative embodiments, a gantry driven ultrasound transducer or a phased array ultrasonic transducer. Methods are provided for generating a mammogram and a plurality of corresponding ultrasound images without moving the breast between the mammogram exposure and the ultrasound imaging. Methods are also provided for viewing and analyzing the ultrasound images. Apparatus and methods are also provided for enhancing X-ray images obtained from conventional mammographic systems, and with reduced overall X-ray dosage to the patient.
    Type: Grant
    Filed: July 20, 1994
    Date of Patent: January 2, 1996
    Assignee: NeoVision Corporation
    Inventor: Ascher Shmulewitz
  • Patent number: 5474072
    Abstract: Apparatus is provided that combines mammography equipment with an ultrasonic transducer to generate ultrasonic images of the internal structure of breast tissue that are in geometric registration with a mammogram. The apparatus includes a radiolucent and sonolucent compression plate, and in alternative embodiments, a gantry driven ultrasound transducer or a phased array ultrasonic transducer. Methods are also provided for generating a mammogram and a plurality of corresponding ultrasound images without moving the breast between the mammogram exposure and the ultrasound imaging.
    Type: Grant
    Filed: October 29, 1993
    Date of Patent: December 12, 1995
    Assignee: NeoVision Corporation
    Inventor: Ascher Shmulewitz
  • Patent number: 5474064
    Abstract: Apparatus and methods for assisting a person perform a self-examination of various body parts including the breasts (B) are disclosed. One of the preferred embodiments of the invention is designed to be used in the privacy of the home shower, either in a standing or seated position. A preferred embodiment (10) includes a pouch ring (12) attached to both a back panel (13) and to the upper portion (14a) of a generally cylindrical, flexible and waterproof retainer pouch (14). The pouch (14) is designed to hold a volume of fluid against the torso below the breasts (B). Although many different fluids may be used to implement the invention, the preferred embodiment of the invention utilizes water (W). Shoulder straps (16) connected to the pouch ring (12) help to bear the weight of the water (W) from the shower head (SH) which fills the pouch (14). The shoulder straps (16) may each include two sections (17) of Velcro.TM. fabric which make the device (10) easier to wear.
    Type: Grant
    Filed: September 17, 1993
    Date of Patent: December 12, 1995
    Inventor: Roderick G. Rohrberg
  • Patent number: 5433202
    Abstract: A synthetic four sided boundary scanner has an electronically switched line array of transducer elements of transducer element on each side of a boundary array scanner, in an ultrasound mammography system. Projector and hydrophone elements are alternately provided in the four line arrays for randomized paired switching operation during a scan of a breast subvolume. Electric signals generated by the hydrophone elements are processed to provide image data for the whole breast volume after sequenced scanning of the breast subvolumes is completed. A breast scan is performed in a sequence of periods within the time between a patient's heartbeats, with synchronization enabled by a heart monitor.
    Type: Grant
    Filed: March 31, 1994
    Date of Patent: July 18, 1995
    Assignee: Westinghouse Electric Corporation
    Inventors: Bruce C. Mitchell, Leslie M. James
  • Patent number: 5007428
    Abstract: An apparatus for the examination of living tissues, comprises an illuminator (228) for illuminating the tissue with infra-red-containing electromagnetic radiation, a television camera (202) for receiving the radiation which is transmitted through the tissue and image devices (216) for producing an image of the received radiation. In addition a probe (224) is provided for applying ultrasound to a region of the tissue and for receiving the reflected ultrasonic signals from the region. The signals obtained are representative of the velocity of blood flow in the region and a computer (216) is provided for generating from the signal an image which provides an indication of blood flow velocity in the region. The apparatus further comprises an arm rotatably mounted on a support about a pivot, the television camera (202) being mounted on the arm on one side of the pivot. A device for holding the tissue to be imaged by the television camera is mounted on the arm on the other side of the pivot.
    Type: Grant
    Filed: December 5, 1989
    Date of Patent: April 16, 1991
    Assignee: The University Court of the University of Aberdeen
    Inventor: David J. Watmough
  • Patent number: 5003979
    Abstract: There is disclosed an image processing, pattern recognition and computer graphics system and method for the noninvasive identification and evaluation of female breast cancer including the characteristic of the boundary thereof using multidimensional Magnetic Resonance Imaging (MRI). The system and method classifies the tissue using a Fisher linear classifier followed by a refinement to show the boundary shape and whether the surface of the carcinoma is lobulated or spiculated. The results are a high information content display which aids in the diagnosis and analysis of breast cancer and to assist in any surgical or other remedial planning. The high information content display also assists in the assessment of the effectiveness of therapies showing any reduction or increase in the size of the carcinoma.
    Type: Grant
    Filed: February 21, 1989
    Date of Patent: April 2, 1991
    Assignee: University of Virginia
    Inventors: Michael B. Merickel, Ann H. Adams, James R. Brookeman
  • Patent number: 4905700
    Abstract: An acoustic coupling medium for transmitting ultrasound is disclosed. The medium, which is of use in ultrasonic visualization of the human body, comprises a sheet of hydrogel containing over 90% water, preferably over 95% water. The hydrogel preferably comprises agar, the chains of which are interspersed with chains of polyacrylamide.
    Type: Grant
    Filed: February 5, 1988
    Date of Patent: March 6, 1990
    Assignee: Ed. Geistlich AG fur Chemische Industrie
    Inventors: Heinrich Wokalek, Wolfgang Strasser
  • Patent number: 4870970
    Abstract: An apparatus for transmitting acoustic ultrasonic pulses and for receiving "echos" of the transmitted pulses, comprises a housing, an upstanding wall mounted on the housing defining the mouth of a well, and a transducer mounted in the housing so that the operative part of the transducer is located in the well. The well is substantially watertight and is provided with a jet for introducing water or other fluids to the well, or is pre-filled with fluid.
    Type: Grant
    Filed: May 6, 1988
    Date of Patent: October 3, 1989
    Assignee: Fulmer Limited
    Inventors: Nigel Gray, Simon Knibbs, Patrick A. Finlay, Robert L. Crocker