A vibration apparatus may include a vibration generator including a piezoelectric material and a sensor portion configured at the vibration generator, and thus, may correct or compensate for an electrical characteristic change of the vibration generator and may correct or compensate for a vibration characteristic of the vibration generator. An apparatus including the vibration apparatus is also disclosed.

A display device includes a display panel which displays an image, a cover window which is disposed on a first surface of the display panel, and a first sound generator which is disposed on a second surface opposite the first surface of the display panel and outputs sound by vibrating the display panel. The cover window includes a first lattice pattern area including lattice patterns surrounding the first sound generator in a plan view.

The flat loudspeaker including an enclosure in the form of a support frame, a sound-emitting rectangular membrane attached to the frame, and an electrodynamic vibration exciter located opposite the membrane. Besides, the vibration exciter is attached with one of its ends to the membrane within a special line passing along the plane of the rectangular membrane, emerging from any vertex of the rectangular membrane, and ending at a point on the opposite vertex of the membrane's horizontal side located at a distance of ⅔ of the membrane's opposite side from the top horizontally.

Electrodynamic drive for a flat loudspeaker having an enclosure where the following components are installed: a magnetic system, a cylindrical coil fixed to the frame, a sound-emitting membrane attached to the cylindrical coil former, a system holding the coil within a magnetic gap, and flexible wires for supplying an electrical signal to the coil. While the magnetic system is made as a cylindrical permanent magnet, a ferrite ring with the above mentioned cylindrical magnet and washers, joining them into a single structure.

An electrodynamic actuator (1a . . . 1c) for a plate like structure (25) or membrane (2) is disclosed, which comprises a voice coil (7, 7a, 7b), a magnet system (8) and a plurality of arms (17a . . . 17t) coupling the voice coil (7, 7a, 7b) and the magnet system (8) in a movable manner. The arms (17a . . . 17t) are made of a metal with a fatigue strength of at least 370 N/mm.sup.2 or an ultimate tensile strength of at least 1100 N/mm.sup.2. Each of the arms (17a . . . 17t) comprises at least two arm sections (s, s1, s2), which are arranged movable to each other, and which are connected to each other by means of a damping material (18a . . . 18g) with a tensile storage modulus of 0.1-6000 MPa and a tensile loss factor of at least 0.1, each measured at room temperature of 20° C. Moreover the invention relates to speaker (5) and an electrodynamic transducer (26a, 26b) with such an electrodynamic actuator (1a . . . 1c) and a method of manufacturing an intermediate product for such an electrodynamic actuator (1a . . . 1c).

Disclosed are a voice recognition system and a display device using the same. The disclosed voice recognition system includes a plate structure, a vibration sensor, and a voice recognition device. The plate structure vibrates based on propagation of a voice wave generated from a user, and the vibration sensor is provided in contact with the plate structure to detect the vibration of the plate structure. The voice recognition device recognizes voice of the user by receiving a signal output from the vibration sensor.

An electromagnetic actuator includes an inner magnet arranged relative to an axis, an outer magnet arranged a radial distance from the axis, an inner radial wall of the outer magnet facing an outer radial wall of the inner magnet, the inner and outer radial walls being separated by an air gap, a voice coil arranged in the air gap separating the inner and outer magnets, and an actuator coupling plate attached to the voice coil. During operation of the device electrical activation of the voice coil causes axial motion of the actuator coupling plate.

Speakers for vehicles which can output sound with identical characteristic regardless of shape and dimension of entire components of interiors and exteriors of the speakers and which can be manufactured by small number of components and processes are provided. A speaker for vehicles of the present disclosure includes a vibration component having a plate shape. A vibration surface is formed on a part of the vibration component. A non-vibration surface is formed on a part of the vibration component. A dividing portion divides the vibration surface and the non-vibration surface. A voice coil is fixed on the vibration surface. A holding component is fixed on the non-vibration surface. A magnetic circuit is fixed on the holding component and corresponds to the voice coil.

A display apparatus includes a display unit including a display panel configured to display an image, a curvature variation unit disposed on a rear surface of the display unit and varying a curvature of the display unit, and a vibration unit disposed on the rear surface of the display unit configured to vibrate the display panel.

A display apparatus includes: a display module including a display panel configured to display an image, a vibration plate on a rear surface of the display module, a connection member between the rear surface of the display module and the vibration plate, at least one vibration module on the vibration plate, and an enclosure between the display module and the vibration plate, the enclosure being spaced apart from the vibration module, the enclosure surrounding the vibration module.