Knowles Electronics, Inc.

The Penn State Research Foundation

Stephen C Thompson

Daniel Max Warren

David Earl Schafer

Peter V Loeppert

Michael Pedersen

Mohsin Nawaz

Zouhair Sbiaa

A force feedback actuator includes a pair of electrodes and a dielectric member. The pair of electrodes are spaced apart from one another to form a gap. The dielectric member is disposed at least partially within the gap. The dielectric member includes a first portion having a first permittivity and a second portion having a second permittivity that is different from the first permittivity. The dielectric member and the pair of electrodes are configured for movement relative to each other.

Force feedback actuator for a MEMS transducer

An example apparatus comprises a drive coil energizable by a drive signal, at least one permanent magnet, and at least one magnetic return path element for flux induced by the drive signal, the magnetic return path element, such as a balanced armature, being configured to provide a variable reluctance, so as to reduce nonlinearities in a displacement versus drive signal relationship. Modifying the reluctance versus flux properties of the magnetic return path of a transducer, e.g. the armature of a balanced armature device, allows compensation for nonlinearity arising in another part of the apparatus.

Methods and apparatus for reduced distortion balanced armature devices

A receiver assembly includes a first diaphragm assembly having a diaphragm, and a second diaphragm assembly having a diaphragm. A linkage assembly is coupled to an armature of the receiver. The linkage assembly is also coupled to the first diaphragm assembly and to the second diaphragm assembly.

Apparatus and method for creating acoustic energy in a receiver assembly with improved diaphragms-linkage arrangement

A receiver assembly includes a housing having a fixed housing portion and a shiftable housing portion cooperating to define a hollow cavity. A flexible membrane secured between the fixed housing portion and the shiftable housing portion and adapted to allow relative motion between the fixed and shiftable housing portions. The receiver assembly further includes a magnetic motor assembly including a displaceable drive rod; and a link assembly having a first end fixedly attached to an inner surface of the shiftable housing and a second end coupled to the drive rod. The link assembly translates the shiftable housing portion relative to the fixed housing portion in response to the displacement of the drive rod.

Apparatus and method for generating acoustic energy in a receiver assembly

An apparatus is provided for matching the response of a pair of microphones. The two microphones provide a first and second output, respectively, in response to an audible input. The microphone outputs are subtract from each other to produce a gain control output for operably controlling the gain of the first microphone output, resulting in a gain compensated microphone output. A phase adjustment circuit also is provided responsive to the gain compensated microphone output and a rolloff control output for producing a matching output. The rolloff control output is generated by a phase difference subtractor circuit responsive to both the matching output and the second microphone output. Moreover, the output of at least one of the microphones has a resonance frequency that is shifted to a desired preselected frequency.

Apparatus and method for matching the response of microphones in magnitude and phase

A directional microphone system is disclosed, which comprises circuitry for low pass filtering a first order signal, and circuitry for high pass filtering a second order signal. The system further comprises circuitry for summing the low pass filtered first order signal and the high pass filtered second order signal. A method of determining whether a plurality of microphones have sufficiently matched frequency response characteristics to be used in a multi-order directional microphone array is also disclosed. For a microphone array having at least three microphones, wherein one of the microphones is disposed between the other of the microphones, a method of determining the arrangement of the microphones in the array is also disclosed.

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Naperville, IL, United States of America

Stephen C Thompson