Patents Assigned to Poul Madsen Medical Devices Ltd.
  • Patent number: 5372142
    Abstract: The invention provides a cochlear response audiometer, and new methods for signal generation, detection and processing. The invention preferably uses bone conducted sound, applied to the mastoid, forehead, or any other place with good mechanical contact to the skull, via a vibrator. The bone conducted sound stimulates the cochlea via the skull. The stimulus also produces a sound in the ear canal, but at a very low level, so there is no high level stimulus signal and ringing travelling toward the cochlea at the same time as the cochlear response is travelling back into the ear canal. The responses from the cochlea are recorded, preferably by using a differential amplifier input circuit for the microphone when air-borne response signals are used, and the responses are processed in a way which compensates for the stimulus artefact, by subtracting a scaled-down version of the cochlear response to a large stimulus from the cochlear response to a moderate stimulus.
    Type: Grant
    Filed: February 17, 1993
    Date of Patent: December 13, 1994
    Assignee: Poul Madsen Medical Devices Ltd.
    Inventors: Poul B. Madsen, Hans Kunov