A vibration sensor having a moveable mass being suspended in a suspension member and being adapted to move in response to vibrations or accelerations. The moveable mass and the suspension member move together as a single element. The vibration sensor includes a damping arrangement having a damping fluid or gel. The moveable mass is arranged to interact directly or indirectly with the damping fluid or gel in order to reduce a mechanical resonance peak of the vibration sensor. The damping fluid or gel has a viscosity between 1000 cP and 100000 cP, is kept in position by capillary forces only, and is stable over time without tending to evaporate.

A condenser microphone, including at least one diaphragm, at least one electrode assigned to the diaphragm, comprising at least one ring-shaped insulator holding the electrode, comprising at least one diaphragm ring holding the diaphragm, and a holding ring holding the components mentioned. The mechanical and electrical properties of the condenser microphone are improved where the holding ring includes ceramic material. Preferably, the diaphragm ring and/or the ring-shaped insulator also consist(s) of ceramic material. With further preference, the ceramic material is zirconium oxide.

Some preferred embodiments include a microphone system for receiving sound waves, the microphone including a back plate, a radiation plate, first and second electrodes, first and second insulator layers, a power source and a microphone controller. The radiation plate is clamped to the back plate so that there is a hermetically sealed circular gap between the radiation plate and the back plate. The first electrode is fixedly attached to a side of the back plate proximate to the gap. The second electrode is fixedly attached to a side of the radiation plate. The insulator layers are attached to the back plate and/or the radiation plate, on respective gap sides thereof, so that the insulator layers are between the electrodes. The microphone controller is configured to use the power source to drive the microphone at a selected operating point comprising normalized static mechanical force, bias voltage, and relative bias voltage level. A radius and height of the gap, and a thickness of the radiation plate, are determined using the selected operating point so that a sensitivity of the microphone at the selected operating point is an optimum sensitivity for the selected operating point.

The method of capturing an audio scene includes acquiring sounds having first and second directivities to obtain first and second acquisition signals, respectively, the first directivity being higher than the second directivity, the steps of acquiring being performed simultaneously, and both acquisition signals together representing the audio scene; separately storing the first and second acquisition signals or mixing individual channels in the acquisition signals to obtain first and second mixed signal, respectively, and separately storing the first and second mixed signals, or transmitting the first and second mixed signals or the first and second acquisition signals to a loudspeaker setup and rendering the first mixed signal or the first acquisition signal using a loudspeaker arrangement having a first directivity and simultaneously rendering the second mixed signal or the second acquisition signal using a loudspeaker arrangement having a second directivity, the second loudspeaker directivity being lower than the first one.

The present invention discloses a MEMS device and an electronics apparatus. The MEMS device comprises: a substrate; a MEMS element placed on the substrate; a cover encapsulating the MEMS element together with the substrate; and a port for the MEMS element to access outside, wherein the port is provided with a filter which has mesh holes and includes electrets to prevent particles from entering into the MEMS element.

An acoustic sensor has a semiconductor substrate having an opening, a back plate that is disposed facing the opening of the semiconductor substrate, that is configured to function as a fixed electrode, and that has sound holes that allow passage of air, a vibration electrode film disposed facing the back plate through a void, and a casing configured to house the substrate, the back plate, and the vibration electrode film, and having a pressure hole that allows inflow of air. The acoustic sensor converts transformation of the vibration electrode film into a change in capacitance between the vibration electrode film and the back plate to detect sound pressure.

Magnetic field cancelling audio speakers and associated devices are disclosed. In one embodiment, a utility locator includes an audio speaker device with two loudspeaker drivers positioned and electrically connected to reduce emitted magnetic fields over a range of frequencies corresponding with locator sensing frequencies.

Offset cartridge microphones are provided that include multiple unidirectional microphone cartridges mounted in an offset geometry. Various desired polar patterns and/or desired steering angles can be formed by processing the audio signals from the multiple cartridges, including a toroidal polar pattern. The offset geometry of the cartridges may include mounting the cartridges so that they are immediately adjacent to one another and so that their center axes are offset from one another. The microphones may have a more consistent on-axis frequency response and may more uniformly form desired polar patterns and/or desired steering angles by reducing the interference and reflections within and between the cartridges.

Some preferred embodiments include a microphone system for receiving sound waves, the microphone including a back plate, a radiation plate, first and second electrodes, first and second insulator layers, a power source and a microphone controller. The radiation plate is clamped to the back plate so that there is a hermetically sealed regular convex polygon-, ellipse-, or regular convex elliptic polygon-shaped gap between the radiation plate and the back plate. The first electrode is fixedly attached to a side of the back plate proximate to the gap. The second electrode is fixedly attached to a side of the radiation plate. The insulator layers are attached to the back plate and/or the radiation plate, on respective gap sides thereof, so that the insulator layers are between the electrodes. The microphone controller is configured to use the power source to drive the microphone at a selected operating point comprising normalized static mechanical force, bias voltage, and relative bias voltage level. Relevant dimensions of the gap, and a thickness of the radiation plate, are determined using the selected operating point so that a sensitivity of the microphone at the selected operating point is an optimum sensitivity for the selected operating point.

The present invention provides a MEMS microphone, including: a base with a back cavity; and an electric capacitance system arranged on the base. The electric capacitance system includes a back plate, a first diaphragm and a second diaphragm opposite to the back plate and arranged on an upper and lower sides of the back plate. The MEMS microphone further includes an insulation layer isolating the base, the back plate, the first diaphragm and the second diaphragm, and a sealing space formed between the first diaphragm and the second diaphragm. The pressure in the sealing space is equal to an external pressure.