Capacitive input transducers for middle ear sensing

Abstract

A hearing assistance system senses sound vibrations of an auditory element in the middle ear and provides a stimulus to an auditory sensory element. The vibrations are received through the tympanic membrane, and sensed at the tympanic membrane, malleus, incus, or other auditory element. A capacitive sensor is mechanically or magnetically coupled to a vibrating auditory element, such as the malleus, and time-varying capacitance values resulting from the vibrations are detected. One embodiment allows pivotable mechanical coupling of the capacitive sensor to at least one of the auditory element and a carrier secured within the middle ear. An resulting electrical output signal is provided to the output stimulator for assisting hearing.

What is claimed is:  
     
         1 . A sensor for transducing mechanical sound vibrations in a middle ear into an electrical input signal, the sensor comprising a capacitive element coupled to an auditory element for receiving vibrations therefrom.  
     
     
         2 . The sensor of    claim 1   , wherein the auditory element includes an ossicle.  
     
     
         3 . The sensor of    claim 1   , wherein the mechanical sound vibrations are received through a tympanic membrane.  
     
     
         4 . The sensor of    claim 1   , further comprising a carrier for securing the sensor within the middle ear.  
     
     
         5 . An electromechanical sensor for transducing mechanical sound vibrations in a middle ear into an electrical input signal, the sensor comprising a capacitor having a first portion that is coupled to an auditory element for receiving the vibrations and changing a capacitance value of the capacitor in response thereto.  
     
     
         6 . The sensor of    claim 5   , wherein the capacitor includes a second portion having a fixed position.  
     
     
         7 . The sensor of    claim 6   , wherein the first portion of the capacitor includes a first electrode of the capacitor that is pivotably coupled to the auditory element, and the second portion of the capacitor includes a second electrode of the capacitor.  
     
     
         8 . The sensor of    claim 7   , wherein one of the first and second electrodes of the capacitor includes a rod, and the other of the first and second electrodes includes a sleeve receiving the rod and separated from the rod by a dielectric.  
     
     
         9 . The sensor of    claim 7   , further comprising a carrier that is pivotably coupled to the second electrode of the capacitor.  
     
     
         10 . The sensor of    claim 5   , wherein the first portion of the capacitor is mechanically coupled to the auditory element.  
     
     
         11 . The sensor of    claim 5   , wherein the first portion of the capacitor is magnetically coupled to the auditory element.  
     
     
         12 . An at least partially implantable hearing assistance system, comprising: 
 a capacitive sensor, coupled to an auditory element for receiving vibrations and varying a capacitance value in response thereto;    an amplifier, electrically coupled to the capacitive sensor for amplifying a signal resulting from the varying capacitance value; and    an output stimulator, receiving a signal based on the varying capacitance value, and providing a resulting stimulus to an auditory element.    
     
     
         13 . The system of    claim 12   , further comprising a programmer adapted to be communicatively coupled to the electronics unit.  
     
     
         14 . The system of    claim 13   , wherein the programmer and electronics unit are adapted to be inductively coupled.  
     
     
         15 . A method of transducing a mechanical vibration of an auditory element into at least one electrical signal, the method comprising: 
 coupling a capacitive sensor to the auditory element for receiving the vibrations, thereby resulting in capacitance variations;    sensing the capacitance variations; and    providing an electrical signal in response to the sensed capacitance variations.    
     
     
         16 . The method of    claim 15   , further comprising receiving the vibrations through a tympanic membrane.  
     
     
         17 . The method of    claim 15   , wherein coupling the capacitive sensor to an auditory element includes a mechanical coupling.  
     
     
         18 . The method of    claim 15   , wherein coupling the capacitive sensor to the auditory element includes a magnetic coupling.  
     
     
         19 . The method of    claim 15   , wherein sensing the capacitance variations includes detecting a charge variation.  
     
     
         20 . The method of    claim 19   , wherein detecting a charge variation includes amplifying the detected charge variation.  
     
     
         21 . The method of    claim 15   , wherein sensing the capacitance variations includes detecting a voltage variation.  
     
     
         22 . The method of    claim 21   , wherein detecting the voltage variation includes amplifying the detected voltage variation.