Abstract: An implanted microphone is provided that has reduced sensitivity to vibration and attendant acceleration forces to differentiate between desirable and undesirable components of a transcutaneously received signal. More specifically, the microphone utilizes an output that is indicative of acceleration forces acting on the implanted microphone to counteract and/or cancel the effects of acceleration-induced pressures in an output signal of a microphone diaphragm. In one arrangement, a microphone having two diaphragms pneumatically cancels acceleration pressures. In this arrangement, a first diaphragm receives and generates a response to commingled acoustic and acceleration forces and a second diaphragm is substantially isolated from the acoustic forces. That is, the second diaphragm generates a response to acceleration forces. The displacements of the first and second diaphragms are pneumatically combined.

Abstract: An implantable microphone that includes a hermetically-sealed, enclosed volume and an electret member and back plate disposed with a space therebetween and capacitively coupleable to provide an output signal indicative of acoustic signals incident upon at least one of the electret member and back plate. At least one of the electret member and the back plate may include a plurality of laterally offset portions located in corresponding spatial relation to a plurality of laterally offset regions including the lateral extent of the space. The output signal may be at least one of weighted and weightable in relation to the plurality of laterally offset portions. The electret member may include the plurality of laterally offset portions, and the laterally offset portions may include at least one positively charged dielectric material portion and at least one negatively charged dielectric material portion.

Abstract: The invention is directed to an implanted microphone having reduced sensitivity to vibration. In this regard, the microphone differentiates between the desirable and undesirable vibration by utilizing at least one motion sensor to produce a motion signal when an implanted microphone is in motion. This motion signal is used to yield a microphone output signal that is less vibration sensitive. In a first arrangement, the motion signal may be processed with an output of the implantable microphone transducer to provide an audio signal that is less vibration-sensitive than the microphone output alone. Specifically, the motion signal may be scaled to match the motion component of the microphone output such that upon removal of the motion signal from the microphone output, the remaining signal is an acoustic signal.

Abstract: An implantable device such as a microphone that may be subcutaneously positioned in surrounding soft tissue. The implantable device may include a hermetically-sealed housing and a diaphragm that forms a portion of an outside surface of the housing. The microphone has a density that is no more than 110% of a density of the surrounding soft tissue. In one arrangement, the device may move in at least substantial unison with the surrounding soft tissue in response to a pressure or compression wave propagating through the soft tissue and being received at the device. In another arrangement, the device may include a filler that may be operable to alter the density of the device.

Abstract: A system for reducing subcutaneous migration of an implantable device or housing relative to surrounding soft tissue. For instance, the implantable housing may support a microphone diaphragm. The system includes at least one securement member having at least one aperture extending therethrough that may selectively receive one of a soft tissue securement device (e.g., soft tissue suture) and soft tissue growth therethrough. The securement member is at least one of interconnected to and disposable over at least a portion of the housing and at least one of extends away from and is selectively extendable away from a periphery of the housing. In one arrangement, at least one mesh member may be optionally included with the system that may allow for tissue growth to enhance securement of the implanted device relative to the soft tissue.

Abstract: The invention is directed to an implanted microphone having reduced sensitivity to vibration. In this regard, the microphone differentiates between the desirable and undesirable vibration by utilizing at least one motion sensor to produce a motion signal when an implanted microphone is in motion. This motion signal is used to yield a microphone output signal that is less vibration sensitive. In a first arrangement, the motion signal may be processed with an output of the implantable microphone transducer to provide an audio signal that is less vibration-sensitive than the microphone output alone. In another arrangement, the motion signal may be utilized to actuate at least one actuator. Such an actuator may be capable of applying a force to move the implantable microphone or an implant capsule so as to reduce movement of a microphone diaphragm relative to the skin of a patient which covers the microphone diaphragm.

Abstract: An implantable microphone comprises a hermetically-sealed, enclosed volume and an electret member and back plate disposed with a space therebetween and capacitively coupleable to provide an output signal indicative of acoustic signals incident upon at least one of the electret member and back plate. The back plate may be disposed to define a peripheral portion of the enclosed volume, e.g., the back plate may be defined as part of a flexible diaphragm that receives external acoustic signals. Vents may be provided to fluidly interconnect first and second portions of the enclosed volume that are located on first and second sides of the electret member. In another embodiment, the electret member may be flexible and spaced relative to a flexible outer diaphragm.

Abstract: An implantable microphone is disclosed having an external diaphragm and housing that forming chamber capable of being pressurized by deformational movement of the diaphragm induced by pressure waves (e.g., acoustic signals) propagating through overlying tissue. The chamber is shaped such that the volume of the chamber upon deflection of the diaphragm is reduced compared to a static volume of the chamber (i.e., volume of the chamber with no diaphragm deflection). As a result, the change in pressure within the chamber for a given diaphragm displacement is greater than it would be within a chamber having a cylindrical volume, leading to greater microphone sensitivity. In one arrangement, the chamber is shaped such that it is deeper at its center than at its edges, for example, to form a conical or paraboloidal volume.

Abstract: Provided is an implanted hearing instrument having reduced sensitivity to vibration. In this regard, the instrument differentiates between the desirable and undesirable signals within an implanted microphone response. In one arrangement, an observer identifies a current operating state of the implanted hearing instrument and one or more cancellation filters are adjusted based on the current operating state. The cancellation filter(s) are used to reduce undesired signals form the implanted microphone response. In a first arrangement, the output of the implanted hearing instrument may be filtered and removed from the implanted microphone response to reduce or substantially eliminate feedback in the microphone signal provided to an implanted signal processor.

Abstract: The invention is directed to an implanted microphone having reduced sensitivity to vibration. In this regard, the microphone differentiates between the desirable and undesirable vibration by utilizing at least one motion sensor to produce a motion signal when an implanted microphone is in motion. This motion signal is used to yield a microphone output signal that is less vibration sensitive. In a first arrangement, the motion signal may be processed with an output of the implantable microphone transducer to provide an audio signal that is less vibration-sensitive than the microphone output alone. Specifically, the motion signal may be scaled to match the motion component of the microphone output such that upon removal of the motion signal from the microphone output, the remaining signal is an acoustic signal.

Abstract: An implantable microphone is disclosed having an external diaphragm and housing that forming chamber capable of being pressurized by deformational movement of the diaphragm induced by pressure waves (e.g., acoustic signals) propagating through overlying tissue. The chamber is shaped such that the volume of the chamber upon deflection of the diaphragm is reduced compared to a static volume of the chamber (i.e., volume of the chamber with no diaphragm deflection). As a result, the change in pressure within the chamber for a given diaphragm displacement is greater than it would be within a chamber having a cylindrical volume, leading to greater microphone sensitivity. In one arrangement, the chamber is shaped such that it is deeper at its center than at its edges, for example, to form a conical or paraboloidal volume.

Abstract: A variable reluctance motor is provided having a linear relationship between an input current and an output force. According to one aspect of the invention, the motor comprises a stator, an armature, and at least one magnetic member to provide a biasing force on the armature. According to this characterization, the motor also includes a drive coil to generate an electromagnetic field in response to a current input. The electromagnetic field, in turn, moves the armature relative to the stator during motor operation.

Abstract: A method for reducing oscillation of a feedback signal in a hearing aid and hearing aid configured according to the present method is provided. The method includes the steps of determining the phase of the feedback signal over a feedback path of the hearing aid and shifting only the phase of the feedback signal a predetermined amount, without modification of other signal characteristics, to achieve a non-zero net phase of the feedback signal over the feedback path such that oscillation of the signal is prevented. In one embodiment of the present method, the step of determining the phase may be performed at the time of fitting of the hearing aid to a patient. In another embodiment of the present method, the method includes the step of periodically determining the phase of the feedback signal over the feedback path such that the phase shifting may be performed based on the periodically determined phase.

Abstract: A noninvasive method and system are provided for assessing the performance of implanted actuators of semi or fully-implantable hearing aid systems. The invention utilizes an externally positioned measurement device to obtain a test measure of the electrical signal passing through an implanted actuator when driven by a test signal of predetermined characteristics. In one embodiment, the measurement device may comprise a pair of coils for measuring the magnetic field generated by an implanted actuator utilized to simulate the middle ear of a patient. The magnetic field strength is directly related to the amount of current passing through the actuator. In turn, such current is inversely related to the electrical impedance present at the implanted actuator. Such electrical impedance is directly related to the mechanical impedance present at the interface between the implanted actuator and middle ear of a patient.

Abstract: A hearing aid transducer that includes an actuator advanceable relative to the transducer to couple with a middle ear component. In one aspect of the invention, the actuator is a separate structure from the transducer that is insertable into an aperture defined between a first and second end of the transducer. This permits separate connection of the actuator to the middle ear component and the transducer to improve coupling of the transducer to the middle ear component, e.g., minimizing loads on the middle ear component.

Abstract: A system for reducing the vibration sensitivity of an implantable microphone without an equal or greater reduction in sound sensitivity. The system reduces non-ambient vibrations by placing at least one compliant member into the path of transmission for tissue-borne vibration, but not into the path for ambient sound-induced vibration. More particularly, a compliant member is interposed along the path between a source of non-ambient vibration and an implanted microphone. In one aspect, a compliant base member is disposed between an implanted microphone and an implant wearer's skull. In another aspect, a microphone is compliantly suspended relative to an implant housing using a support membrane. In either aspect, the compliant member (i.e., base member and/or membrane) and the supported member (i.e., housing and/or microphone) define a supported system having a natural or resonant frequency. This natural frequency may be set to a value to advantageously isolate the microphone against transmitted vibration.

Abstract: An implanted microphone is provided that has reduced sensitivity to vibration and attendant acceleration forces. In this regard, the microphone differentiates between the desirable and undesirable components of a transcutaneously received signal. More specifically, the present invention utilizes an output that is indicative of acceleration forces acting on the implanted microphone (e.g., an acceleration signal) to counteract and/or cancel the effects of acceleration induced pressures in an output signal of a microphone diaphragm. This may be done in a variety of ways, including but not limited to, pneumatically, mechanically, electrical analog, or digitally, or combinations thereof. In one arrangement, the generated output may be filtered to match the an acceleration response of the output signal of the microphone diaphragm such that upon removal of the motion signal from the microphone output, the remaining signal is an acoustic signal.

Abstract: An implantable microphone for use with an implantable hearing instrument that has a reduced vibration sensitivity in comparison with its acoustic sensitivity. The microphone utilizes a plurality of small diaphragms as opposed to a single large diaphragm in order to reduce vibration sensitivity caused by mass loading of the diaphragms by overlying skin and tissue. The acoustic outputs of the plurality of small diaphragms are summed (e.g., acoustically or electronically), which allows the microphone to maintain adequate acoustic sensitivity for hearing augmentation purposes while having a reduced vibration sensitivity. In one aspect, the plurality of diaphragms is formed from a single membrane and a multi-apertured support structure in contact with the membrane. Each aperture in combination with the membrane defines a single diaphragm.

Abstract: A system and method to compensate for changes in the frequency response of a microphone caused by factors interfering with the receipt of acoustic sound in the microphone. The system includes at least a microphone and a signal processor. The signal processor is operational to process at least one feedback frequency response from the microphone to generate at least one test parameter. The signal processor uses the at least one test parameter to determine at least one operational characteristic of the microphone. The feedback frequency response is generated by the microphone in response to acoustic feedback. The acoustic feedback is generated by actuation of a transducer in response to at least one test signal that is provided to the transducer. The signal processor uses the at least one test parameter to process acoustic frequency responses from the microphone to compensate for changes in the acoustic frequency responses of the microphone.

Abstract: An implantable hearing aid transducer including a transducer housing, a driver, and an actuator movably connected to the transducer housing. The transducer driver includes at least one coil and one magnet. In one aspect of the present transducer, a seal is provided to seal transducer components that are located at a location other than at the movable connection between the actuator and the transducer housing. According to this aspect, the seal may be disposed around one of a magnet and a coil that is connectable to the actuator, to protect the same from body fluids. The other one of the magnet and the coil may include its own seal within the transducer housing.