In an embodiment, the invention provides a structure of MEMS microphone includes a substrate of semiconductor, having a first opening in the substrate. A dielectric layer is disposed on the substrate, having a dielectric opening. A diaphragm is within the dielectric opening and held by the dielectric layer at a peripheral region, wherein the diaphragm has a diaphragm opening. A back-plate is disposed on the dielectric layer, over the diaphragm. A protruding structure is disposed on the back-plate, protruding toward the diaphragm. At least one air valve plate is affixed on an end of the protruding structure within the diaphragm opening of the diaphragm. The air valve plate is activated when suffering an air flow with a pressure.

According to certain embodiments, a microphone array having a plurality of microphone elements is calibrated by ensonifying the microphone array at a first direction relative to the microphone array with a first acoustic signal to concurrently generate a first set of audio signals from two or more of the microphone elements and processing the first set of audio signals to calibrate the two or more microphone elements. One or more other sets of audio signals can be generated by ensonifying the microphone array with one or more other acoustic signals at one or more other directions relative to the microphone array, where the two or more microphone elements are calibrated using the first set and the one or more other sets of audio signals. The calibration process can be performed outside of an anechoic chamber using one or more acoustic sources located outside or inside the microphone array.

Microphone capsules for condenser or electret microphones often exhibit individual deviations from a desired ideal behavior, e.g. the frequency response and phase response. Particularly if a plurality of microphone capsules are interconnected to form a microphone array, suitable microphone capsules must be found in a selection process. Some of these deviations can be corrected electronically, e.g. by filtering with a corresponding filter that is individually adapted. An improved microphone capsule, with which an automatic selection and automatic assembly of circuit boards with microphone capsules is facilitated, comprises an electrostatic sound transducer, an amplifier element that outputs an amplified output signal of the electrostatic sound transducer, and at least one electronic memory element. Data obtained by a measurement and relating to the individual frequency response or phase response of the respective microphone capsule can be stored therein. The data can be read out during manufacturing and during operation, which enables automatic sorting of the capsules during production and automatic calibration of the target circuit in operation.

A sensor module comprising a housing defining an internal cavity, the housing including an aperture, at least one microphone positioned in the internal cavity spaced from the aperture, a first barrier proximate the aperture, and a second barrier positioned between the at least one microphone and the first barrier.

A microphone assembly includes a shaft element that is configured to be received in an opening defined by a base substrate layer of a headliner. The shaft element defines an air path. The microphone assembly includes a microphone element mounted on a circuit board within a housing. The microphone element is aligned with the air path such that the air path directs sound from the cabin to the microphone element. A vehicle cabin side of the headliner is covered by an acoustically transparent layer such that the microphone assembly is not visible within the vehicle cabin.

A vibration sensor includes a circuit board, a spacer, a pressure sensing device and a housing. The spacer is located on the circuit board. The pressure sensing device is located on the spacer, and the circuit board, the spacer and the pressure sensing device jointly form a first chamber and an air gap. The housing is mounted on the circuit board to defining a third chamber along with the circuit board, wherein the air gap allows the first chamber venting to the third chamber.

The waterproof microphone according to the present invention comprises: a case that includes a partition wall separating an internal space into two chambers, a front chamber and a rear chamber, a hole in the partition wall for allowing communication between the front chamber and the rear chamber, and opening portions in surfaces of the front chamber and the rear chamber that face the partition wall; a waterproof vibrating membrane covering the opening portion of the front chamber; a microphone unit attached to a surface of the partition wall on the rear chamber side; and a sealing member sealing the opening portion of the rear chamber and including an air hole allowing communication between the rear chamber and an external space.

A sensing arrangement for detection of electrical discharges in an electrical apparatus is described. The sensing arrangement includes an acoustic sensor and a signal enhancing structure with a funnel region. The acoustic sensor is positioned outside the funnel region on an apex side of the funnel region. An electrical switchgear is described. The electrical switchgear includes a sensing arrangement for detection of electrical discharges in an electrical apparatus. The sensing arrangement includes an acoustic sensor and a signal enhancing structure with a funnel region.

A spatial-audio recording system includes a spatial-audio recording device including a plurality of microphones, and a computing device. The computing device is configured to determine a plane-wave transfer function for the spatial-audio recording device based on a physical shape of the spatial-audio recording device and to expand the plane-wave transfer function to generate a spherical-harmonics transfer function corresponding to the plane-wave transfer function. The computing device is further configured to retrieve a plurality of signals captured by the microphones, determine spherical-harmonics coefficients for an audio signal based on the plurality of captured signals and the spherical-harmonics transfer function, and generate the audio signal based on the determined spherical-harmonics coefficients.

An electronic device includes a housing; a printed circuit board; a microphone substrate; a microphone; a flash; a cover, the cover having an opening at least partially aligned with the flash; a flash window facing the cover, the flash window including a first part at least partially accommodated in the opening and at least partially aligned with the flash in the first direction, and a second part extended from the first part and between the cover and the microphone substrate; and an audio input path configured to propagate a sound wave to the microphone, wherein the audio input path may include a space provided between the flash window and the cover, a gap provided between the first part and an inner wall of the opening and fluidly connected to the space, and a microphone hole in the second part and fluidly connected to the microphone and the space.