The invention relates to audio transducers, such as loudspeaker, microphones and the like, and includes improvements in or relating to: audio transducer diaphragm structures and assemblies, audio transducer mounting systems; audio transducer diaphragm suspension systems, personal audio devices incorporating the same and any combination thereof. The embodiments of the invention include linear action and rotational action transducers. For both types of transducer, rigid and composite diaphragm constructions and unsupported diaphragm periphery designs are described. Systems and methods for mounting the transducer to a housing, such as an enclosure or baffle are also described. Furthermore, hinge systems including: rigid contact hinge systems and flexible hinge systems are also disclosed for various rotational action transducer embodiments. Various applications and implementations are described and envisaged for the audio transducer embodiments including, for example, personal audio devices such as headphones, earphones and the like.

Aheadphone configured to emit a fractal-polarized sound field is provided. The headphone comprises a sound-emitting membrane, an acoustic oscillator, and an ear pad. The sound-emitting membrane comprises a paper-based composite material layer, a metal layer, and a coating layer. The paper-based composite material layer has a front surface and a rear surface, with the front surface facing a user ear. The metal layer is provided on the front surface of the paper-based composite material layer and configured to reproduce HF acoustic oscillations. The coating layer is provided on the metal layer and has one or more slots through which the metal layer is visible. The coating layer is made of a material incapable of reproducing the HF acoustic oscillations. The acoustic oscillator generating the acoustic oscillations is attached to the rear surface of the paper-based composite material layer. The ear pad is configured to cover the coating layer.

A double sided speaker device, comprising a magnetic conductive carrier board, a first magnetic circuit module, a second magnetic circuit module, a first voice coil, a second voice coil, a first sounding hood, and a second sounding hood. The magnetic conductive carrier board comprises a plurality of openings. The first magnetic circuit module is disposed at one side of the magnetic conductive carrier board. The second magnetic circuit module is disposed at the other side of the magnetic conductive carrier board. The first voice coil is disposed around the first magnetic circuit module. The second voice coil is disposed around the second magnetic circuit module. The first sounding hood is disposed at one side of the magnetic conductive carrier board and comprises a first accommodating space. The second sounding hood is disposed at the other side of the magnetic conductive carrier board and comprises a second accommodating space.

A double sided speaker device, comprising a magnetic conductive carrier board, a first magnetic circuit module, a second magnetic circuit module, a first voice coil, a second voice coil, a first sounding hood, and a second sounding hood. The magnetic conductive carrier board comprises a plurality of openings. The first magnetic circuit module is disposed at one side of the magnetic conductive carrier board. The second magnetic circuit module is disposed at the other side of the magnetic conductive carrier board. The first voice coil is disposed around the first magnetic circuit module. The second voice coil is disposed around the second magnetic circuit module. The first sounding hood is disposed at one side of the magnetic conductive carrier board and comprises a first accommodating space. The second sounding hood is disposed at the other side of the magnetic conductive carrier board and comprises a second accommodating space.

Provided is a curing reactive organopolysiloxane composition that forms a pressure-sensitive adhesive layer having excellent curing properties, a wide range of designable viscoelastic properties such as storage elastic modulus (G′) and the like, and practically sufficient pressure-sensitive adhesive strength and tensile adhesive strength. The organopolysiloxane composition comprises: (A) an organopolysiloxane having an alkenyl group; (B) an organopolysiloxane resin with 9 mol % or less of hydroxyl groups or the like relative to all silicon atoms in a molecule or resin mixture thereof; (C) an organohydrogenpolysiloxane; (D) an organic silicon compound having an alkenyl group; and (E) a hydrosilylation reaction catalyst. A ratio (molar ratio) of the substance amount of SiH groups in component (C) relative to the sum of alkenyl groups in components (A), (B) and (D) is 1.0 or less.

The present invention discloses a vibration diaphragm in an MEMS microphone, and an MEMS microphone. The vibration diaphragm comprises a vibration diaphragm body and at least one pressure relief device defined by gaps in the vibration diaphragm body, wherein the gaps comprise at least two sections of circular arc-shaped gaps sequentially connected together. The two adjacent sections of circular arc-shaped gaps are in an S shape as a whole and centrosymmetrical with respect to a connected position thereof. The pressure relief device comprises at least two valve clacks formed by at least two sections of adjacent circular arc-shaped gaps and neck portions connected to the valve clacks and the vibration diaphragm body and of a constraint shape.

The present invention discloses a vibration diaphragm in an MEMS microphone, and an MEMS microphone. The vibration diaphragm comprises a vibration diaphragm body and at least one pressure relief device defined by gaps in the vibration diaphragm body, wherein the gaps comprise at least two sections of circular arc-shaped gaps sequentially connected together. The two adjacent sections of circular arc-shaped gaps are in an S shape as a whole and centrosymmetrical with respect to a connected position thereof. The pressure relief device comprises at least two valve clacks formed by at least two sections of adjacent circular arc-shaped gaps and neck portions connected to the valve clacks and the vibration diaphragm body and of a constraint shape.

An MEMS microphone is provided, comprising: a first substrate; a vibration diaphragm supported above the first substrate by a spacing portion, the first substrate, the spacing portion, and the vibration diaphragm enclosing a vacuum chamber, and a static deflection distance of the vibration diaphragm under an atmospheric pressure being less than a distance between the vibration diaphragm and the first substrate; and a floating gate field effect transistor outputting a varying electrical signal, the floating gate field effect transistor including a source electrode and a drain electrode both provided on the first substrate and a floating gate provided on the vibration diaphragm.

An MEMS microphone is provided, comprising: a first substrate; a vibration diaphragm supported above the first substrate by a spacing portion, the first substrate, the spacing portion, and the vibration diaphragm enclosing a vacuum chamber, and a static deflection distance of the vibration diaphragm under an atmospheric pressure being less than a distance between the vibration diaphragm and the first substrate; and a floating gate field effect transistor outputting a varying electrical signal, the floating gate field effect transistor including a source electrode and a drain electrode both provided on the first substrate and a floating gate provided on the vibration diaphragm.

A loudspeaker diaphragm (12) comprising a woven fibre body supports damping material (25), for example PVA polymer, on a rearward-facing surface (24). The woven fibre body may be formed of lengths (14) non-metallic fibre material (for example glass fibre) coating with a thin metal coating (32). The mass of the layer of damping material (25) may be less than the mass of the woven fibre body. An attractive sparkly looking loudspeaker diaphragm (12) may thus be provided which damps undesirable vibration whilst providing a flatter frequency-response curve (50).