A display apparatus includes a display module including a display panel configured to display an image, a rear cover on a rear surface of the display module, and a sound generating module at the rear cover and configured to vibrate the display module to generate sound, and a rear surface of the sound generating module is covered by the rear cover.

A MEMS device and a method of manufacturing the same are provided. A semiconductor device includes a substrate; and a membrane over the substrate and configured to generate charges in response to an acoustic wave, the membrane being in a polygonal shape including vertices. The membrane includes a via pattern having first lines that partition the membrane into slices and extend to the vertices of the membrane such that the slices are separated from each other near an anchored region of the membrane and connected to each other around a central region. The via pattern further includes second lines extending from the anchored region of the membrane toward the central region of the membrane. Each of the second lines includes a length less than a length of each of the first lines.

An improved compact electroacoustic transducer and loudspeaker system. The electroacoustic transducer (or array of electroacoustic transducers) can generate the desired sound by the use of pressurized airflow. The electroacoustic transducer uses a shared stator with an array of vent support fingers and metal frame instead of two stators per electroacoustic transducer.

Disclosed is a display device that includes a display panel, sound generating actuators including a first sound generating actuator in a first area of the display panel and a second sound generating actuator in a second area of the display panel, the first and second sound generating actuators configured to vibrate the display panel to generate sound, and a partition between the first sound generating actuator and the second sound generating actuator.

A piezoelectric speaker device that includes an organic polymer piezoelectric film, at least one pair of electrodes provided in contact with the piezoelectric film and the at least one pair of electrodes including a user-side electrode on a first side of the piezoelectric film, an insulation layer on the user-side electrode, a flaw detection electrode line on the insulation layer, and a detection circuit configured to detect whether the flaw detection electrode line is in a normal electric conduction state.

Embodiments of the present disclosure relate to an organic light emitting display device which directly vibrates an organic light emitting display panel to generate sound, and includes: an organic light emitting display panel including a light emitting layer including an organic light emitting material layer and an encapsulation layer disposed at one side of the light emitting layer; and a sound generating actuator in direct contact with the organic light emitting display panel to vibrate the organic light emitting display panel to generate sound. Especially, the organic light emitting display panel is a bottom emission type device, and thus can prevent generation of a weighted color mixing phenomenon in a wide viewing angle at the time of panel vibration and reduce the thickness or weight of the panel to thereby enhance the sound generation characteristic.

An audio system includes an audio panel. The audio panel includes a first face plate, a second face plate, and a core that includes a plurality of structural members that extend between the first face plate and the second face plate. The plurality of structural members define a plurality of cavities in the core. The audio system also includes a first piezoelectric actuator mounted to at least one of the first face plate, the second face plate, and the core. The first piezoelectric actuator is configured to convert electrical signals into mechanical energy to cause the audio panel to generate sound.

A passive carbon nanotube transducer is provided. The passive carbon nanotube transducer includes shells as protective walls for the top and bottom housing of the transducer with carbon nanotube sheets affixed between the shells. The shells act as acoustic windows that match the surrounding acoustic medium. A gasket encloses the shells and carbon nanotube sheets of the transducer. Each carbon nanotube sheet has an electrode at both ends. Multiple carbon nanotube sheets are capable of sensing sound induced environment temperature deviations and converting electric voltage or current for passive acoustic detection.

Materials used in acoustic transducer membranes need very specific qualities that in any real system require many tradeoffs to be made. Graphene and graphene related materials are a newly discovered class of materials with some exceptional properties that offer the potential for significant contributions to the performance of many acoustical transduction systems. Accordingly the inventors have established graphene oxide based transducers as the basis of ribbon microphones and diaphragm loudspeakers using low cost manufacturing and processing techniques.

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.