Patents by Inventor Douglas H. Keefe

Douglas H. Keefe has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 8840565
    Abstract: A test battery method and system for use in assessing auditory function (e.g., the screening or diagnosis of impairments, fitting of hearing aids, etc.) is provided which performs one or more auditory tests including, for example, an acoustic reflectance test. Such an acoustic reflectance test may be a reflectance tympanometry test that includes a feedback system to control static pressure in the ear canal. Such acoustic reflectance tests may be used alone or in combination with one or more other auditory tests. Further, for example, such a battery of tests may include middle-ear muscle reflex tests in combination with one or more other auditory or hearing tests.
    Type: Grant
    Filed: August 8, 2012
    Date of Patent: September 23, 2014
    Assignee: Sonicom, Inc.
    Inventor: Douglas H. Keefe
  • Publication number: 20120302859
    Abstract: A test battery method and system for use in assessing auditory function (e.g., the screening or diagnosis of impairments, fitting of hearing aids, etc.) is provided which performs one or more auditory tests including, for example, an acoustic reflectance test. Such an acoustic reflectance test may be a reflectance tympanometry test that includes a feedback system to control static pressure in the ear canal. Such acoustic reflectance tests may be used alone or in combination with one or more other auditory tests. Further, for example, such a battery of tests may include middle-ear muscle reflex tests in combination with one or more other auditory or hearing tests.
    Type: Application
    Filed: August 8, 2012
    Publication date: November 29, 2012
    Applicant: SONICOM, INC.
    Inventor: Douglas H. Keefe
  • Patent number: 8241224
    Abstract: A test battery method and system (10, 100, 200, 225) for use in assessing auditory function (e.g., the screening or diagnosis of impairments, fitting of hearing aids, etc.) is provided which performs one or more auditory tests including, for example, an acoustic reflectance test. Such an acoustic reflectance test may be a reflectance tympanometry test that includes a feedback system to control (426) static pressure in the ear canal. Such acoustic reflectance tests may be used alone or in combination with one or more other auditory tests. Further, for example, such a battery of tests may include middle-ear muscle reflex tests in combination with one or more other auditory or hearing tests.
    Type: Grant
    Filed: March 16, 2006
    Date of Patent: August 14, 2012
    Assignee: Sonicom, Inc.
    Inventor: Douglas H. Keefe
  • Publication number: 20080194984
    Abstract: A test battery method and system (10, 100, 200, 225) for use in assessing auditory function (e.g., the screening or diagnosis of impairments, fitting of hearing aids, etc.) is provided which performs one or more auditory tests including, for example, an acoustic reflectance test. Such an acoustic reflectance test may be a reflectance tympanometry test that includes a feedback system to control static pressure in the ear canal. Such acoustic reflectance tests may be used alone or in combination with one or more other auditory tests. Further, for example, such a battery of tests may include middle-ear muscle reflex tests in combination with one or more other auditory or hearing tests.
    Type: Application
    Filed: March 16, 2006
    Publication date: August 14, 2008
    Applicant: SONICOM, INC.
    Inventor: Douglas H. Keefe
  • Patent number: 5885225
    Abstract: A system and method for using double-evoked otoacoustic emission (2EOAE) signals to elicit an evoked response from the cochlea. A three sample stimulus includes a first signal, a time delayed second signal and the superposition of the first and second signals. The time delay is selected to be less than the maximum latency of the cochlear emission. Each of the three signals elicits a response from the cochlea that include a linear response. The linear response is eliminated by subtracting the response to the first and second individual signals from the response to the superposition signal. One class of signals arises when the time delayed signal is a scaled version of the first signal. The signals can include click signals, chirp signal and the like. Chirp signals can be used to mimic classical distortion product (DP) responses. The signals may be presented using a single acoustic source or separate acoustic sources.
    Type: Grant
    Filed: January 23, 1996
    Date of Patent: March 23, 1999
    Assignee: Boys Town National Research Hospital
    Inventors: Douglas H. Keefe, Robert Ling
  • Patent number: 5792072
    Abstract: A system and method of measuring the linear and nonlinear power-based responses of the ear uses a small probe assembly containing a sound source and microphone inserted into the ear. The linear power-based responses, or transfer functions, measured by the system include reflectance, admittance and impedance calculated in the time and frequency domains. A calibration procedure is based upon measured pressure responses in one or more calibration waveguides, and upon a model of the transfer function of each of the calibration waveguides that incorporates viscothermal losses. The linear transfer functions and the measured pressure responses in the ear may be combined to calculate sound power absorbed by the ear. The system is further able to measure the corresponding nonlinear power-based response of the ear by measuring any of the above transfer functions at different levels of the acoustic stimulus.
    Type: Grant
    Filed: April 8, 1996
    Date of Patent: August 11, 1998
    Assignee: University of Washington
    Inventor: Douglas H. Keefe
  • Patent number: 5792073
    Abstract: A system and method for measurement of acoustic response, such as occurs in the ear canal when double-evoked otoacoustic emission signals elicit an evoked response from the cochlea. A three sample stimulus includes a first signal, a time delayed second signal and the useful superposition of the first and second signals. The time delay is less than the maximum latency of the cochlear emission. Each signal elicits a cochlear response that includes a linear response, which is eliminated by subtracting the first and second individual signal responses from the response to the useful superposition signal. One class of signals arises when the time delayed signal is a scaled version of the first signal. The signals may be presented using a single acoustic source or separate acoustic sources. Appropriate selection of time delays greatly reduces nonlinear response due to probe distortion. Using two acoustic sources, probe distortion can be virtually eliminated.
    Type: Grant
    Filed: October 1, 1996
    Date of Patent: August 11, 1998
    Assignee: Boys Town National Research Hospital
    Inventor: Douglas H. Keefe
  • Patent number: 5651371
    Abstract: A system and method of measuring the linear and nonlinear response of an unknown acoustic termination uses a small probe assembly containing a sound source and microphone to determine the reflection function of the unknown acoustic termination. The probe assembly is used with a calibration tube to calculate an electrical signal that will provide a desired acoustic stimulus signal to the acoustic termination. The calibration tube is also used to characterize the signal processing properties of the sound source and microphone, as well as other associated signal processing circuits such as amplifiers, filters, and the like. The calibrated system is subsequently coupled to the unknown acoustic termination to deliver the acoustic stimulus signal. The reflection function is indicative of the power transferred to the unknown acoustic termination. The measurement of the linear transfer characteristic is applicable to any unknown acoustic termination such as a musical instrument or the auditory system.
    Type: Grant
    Filed: May 26, 1995
    Date of Patent: July 29, 1997
    Assignee: The University of Washington
    Inventor: Douglas H. Keefe
  • Patent number: 5594174
    Abstract: A system and method of measuring the linear and nonlinear response of an unknown acoustic termination uses a small probe assembly containing a sound source and microphone to determine the reflection function of the unknown acoustic termination. The probe assembly is used with a calibration tube to calculate an electrical signal that will provide a desired acoustic stimulus signal to the acoustic termination. The calibration tube is also used to characterize the signal processing properties of the sound source and microphone, as well as other associated signal processing circuits such as amplifiers, filters, and the like. The calibrated system is subsequently coupled to the unknown acoustic termination to deliver the acoustic stimulus signal. The reflection function is indicative of the power transferred to the unknown acoustic termination. The measurement of the linear transfer characteristic is applicable to any unknown acoustic termination such as a musical instrument or the auditory system.
    Type: Grant
    Filed: May 26, 1995
    Date of Patent: January 14, 1997
    Assignee: University of Washington
    Inventor: Douglas H. Keefe