Water impermeable, air permeable membrane assemblies are described herein. In some embodiments, the assemblies include a polymer membrane and at least one support structure. Certain assemblies are configured to provide an acoustic impedance having phase angle of +45 degrees to −45 over a frequency range of 50 to 20,000 Hz.

A speaker is disclosed, which comprises a vibration system and a magnetic circuit system cooperating with the vibration system. The vibration system includes a speaker diaphragm, the speaker diaphragm comprises two surface layers compounded together and at least one intermediate layer positioned between the two surface layers, at least one of the surface layers is a thermoplastic polyester elastomer film layer, the at least one intermediate layer is an adhesive layer, the speaker diaphragm has Young's modulus of 5-700 MPa and an amplitude of 0.25 mm-1 mm, and the speaker has F.sub.0 of 150-1500 Hz. The speaker has a good sounding effect.

The present disclosure provides a speaker diaphragm and a speaker. The diaphragm includes a thermoplastic polyester elastomer film layer (11), a thermoplastic polyester elastomer being a copolymer composed of a polyester hard segment A and a polyether or aliphatic polyester soft segment B, wherein a mass percentage of the polyester hard segment A is 10-95%. The speaker diaphragm features high structural strength, is not easy to be damaged, and has good toughness and resilience and a good sound generation effect.

The present invention provides a speaker system comprising: an electroacoustic converter film composed of a polymeric composite piezoelectric body in which piezoelectric body particles are dispersed in a viscoelastic matrix formed of a polymer material that exhibits viscoelasticity at normal temperature, and thin film electrodes formed on both surfaces of the polymeric composite piezoelectric body; and a driving circuit that attenuates signal intensity of an input signal from a signal source at a rate of 5 dB to 7 dB per octave and supplies the attenuated input signal to the electroacoustic converter film.

Provided is a panel vibration type sound-generating display device. A display device includes: a display panel configured to display an image, a cover bottom configured to cover the display panel, a sound-generating actuator supported by the cover bottom, the sound-generating actuator configured to vibrate the display panel to generate sound, and a sealing member between an outer peripheral portion of the sound-generating actuator and an outer surface of the cover bottom.

The present invention relates to a loudspeaker 1 including a cone 20 having a central aperture with a cone collar 28 upstanding from the perimeter of the central aperture 26 of the cone, a spider 30 having a central aperture 36, the spider having a collar 38 upstanding from the perimeter of the central aperture of the spider, and a voice coil former 40. The collar of each of the cone and the spider are concentrically located around an end region of the voice coil former to form an elongate neck region 12. The use of the elongate neck region allows for the cone, spider and voice coil former to be joined more easily therefore forming a more reliable and durable join.

Aspects of a microelectromechanical device, an array of microelectromechanical devices, a method of manufacturing a microelectromechanical device, and a method of operating a microelectromechanical device, are discussed herein. The microelectromechanical device may include: a substrate; a diaphragm mechanically coupled to the substrate, the diaphragm comprising a stressed region to buckle the diaphragm into one of two geometrically stable positions; an actuator mechanically coupled to the diaphragm, the actuator comprising a piezoelectric layer over the diaphragm; a controller configured to provide an electrical control signal in response to a digital sound input; wherein the actuator is configured to receive the electrical control signal to exert a mechanical piezoelectric force on the diaphragm via the piezoelectric layer to move the diaphragm to create a sound wave.

A piezoelectric speaker-forming laminate (10) includes: a piezoelectric film (35); a pressure-sensitive adhesive face (17); an interposed layer (40) being a porous body layer and/or a resin layer disposed between the piezoelectric film (35) and the pressure-sensitive adhesive face (17); and a release layer (20) joined to the pressure-sensitive adhesive face (17). The pressure-sensitive adhesive face (17) is disposed in such a manner that at least a portion of the piezoelectric film (35) overlaps the pressure-sensitive adhesive face (17) when the piezoelectric film (35) is viewed in plan. The piezoelectric film (35) and the interposed layer (40) are allowed to be fixed to a support (80) as a piezoelectric speaker or a portion of a piezoelectric speaker by sticking the pressure-sensitive adhesive face (17) from which the release layer (20) has been removed to the support (80).

An acoustic diaphragm made at least in part from an expanded material. The expanded material includes one or more of cellulose, synthetic fibers and glass fibers. The expanded material has more than about 55% by volume voids.

Provided is an electroacoustic converter film including: a polymeric composite piezoelectric body having piezoelectric particles dispersed in a viscoelastic matrix which is formed of a polymer material exhibiting viscoelasticity at ordinary temperatures; thin film electrodes formed on both sides of the polymeric composite piezoelectric body; and protective layers formed on surfaces of the thin film electrodes. The electroacoustic converter film serves as a speaker capable of being integrated with a flexible display without impairing lightweightness or flexibility, and has considerable frequency dispersion in the storage modulus and also has a local maximum of the loss tangent around ordinary temperatures. A flexible display, a vocal cord microphone and a musical instrument sensor, in each of which the electroacoustic converter film is used, are also provided.