In accordance with an embodiment, a microelectromechanical transducer includes a displaceable membrane having an undulated section comprising at least one undulation trough and at least one undulation peak and a plurality of piezoelectric unit cells. At least one piezoelectric unit cell is provided in each case in at least one undulation trough and at least one undulation peak, where each piezoelectric unit cell has a piezoelectric layer and at least one electrode in electrical contact with the piezoelectric layer. The membrane may be formed as a planar component having a substantially larger extent in a first and a second spatial direction, which are orthogonal to one another, than in a third spatial direction, which is orthogonal to the first and the second spatial direction and defines an axial direction of the membrane.

A display device includes: a display panel including a substrate and a pixel array layer disposed on a surface of the substrate; a sound generation device disposed on an opposing surface opposite to the surface of the substrate; and a set cover including a plurality of ribs which overlap the sound generation device in a thickness direction of the display panel. The sound generation device vibrates the display panel to output a sound.

An audio device includes a thin film material having a capacitive property, the thin film material including an acoustic sheet having a curved shape, in which the acoustic sheet includes a first region that is actively driven by an input signal and a second region that is not actively driven by the input signal and the first region is formed in at least a part of an outside of the second region.

The present disclosure relates to a vibration generation device, a display apparatus including the vibration generation device, and a vehicle including the vibration generation device. A vibration generation device includes a piezoelectric ceramic part having a certain interval, a piezoelectric material layer between the piezoelectric ceramic parts, and an electrode part configured to provide electric field to one or more of the piezoelectric ceramic part and the piezoelectric material layer.

A MEMS sound transducer includes a substrate, a membrane formed within the substrate, and a bending actuator applied onto the membrane. The membrane includes at least one integrated permanent magnet and is electrodynamically controllable. The bending actuator can be piezoelectrically controlled separately from the membrane.

In accordance with an embodiment, a microelectromechanical transducer includes a displaceable membrane having an undulated section comprising at least one undulation trough and at least one undulation peak and a plurality of piezoelectric unit cells. At least one piezoelectric unit cell is provided in each case in at least one undulation trough and at least one undulation peak, where each piezoelectric unit cell has a piezoelectric layer and at least one electrode in electrical contact with the piezoelectric layer. The membrane may be formed as a planar component having a substantially larger extent in a first and a second spatial direction, which are orthogonal to one another, than in a third spatial direction, which is orthogonal to the first and the second spatial direction and defines an axial direction of the membrane.

A piezoelectric microphone includes a plate, a support portion that is provided around the plate, connection portions that connect the plate and the support portion on two or more sides of the plate, and a detection portion including a lower electrode, a piezoelectric film, and an upper electrode which are stacked in this order. The detection portion is stacked on the connection portion . An inflection point of a cross-sectional deformation curve in a case in which the plate and the connection portion are deformed by sound pressure is present in a region in which the detection portion is not stacked.

Provided is a piezoelectric element capable of preventing the occurrence of poor connection to an electrode layer. A piezoelectric element includes a piezoelectric layer, electrode layers formed on both sides of the piezoelectric layer, and a protective layer laminated on a surface of the electrode layer opposite to a surface on a piezoelectric layer side, in which the piezoelectric element includes a conductive foil laminated on a surface of the protective layer opposite to the electrode layer, the protective layer has a hole that penetrates from a surface to the electrode layer, the conductive foil includes an opening portion at a position that overlaps with the hole of the protective layer in a surface direction, the piezoelectric element includes a filling member consisting of a conductive material, which is formed on at least a part of a surface of the conductive foil from insides of the hole of the protective layer and an opening portion of the conductive foil and is electrically connected to the electrode layer and the conductive foil, and a covering member that covers the filling member and the conductive foil, the covering member has a through-hole at a position that does not overlap with the filling member in the surface direction, and the piezoelectric element includes a conductive member, which is inserted into the through-hole of the covering member and electrically connected to the conductive foil.

In accordance with an embodiment, a microelectromechanical transducer includes a displaceable membrane having an undulated section comprising at least one undulation trough and at least one undulation peak and a plurality of piezoelectric unit cells. At least one piezoelectric unit cell is provided in each case in at least one undulation trough and at least one undulation peak, where each piezoelectric unit cell has a piezoelectric layer and at least one electrode in electrical contact with the piezoelectric layer. The membrane may be formed as a planar component having a substantially larger extent in a first and a second spatial direction, which are orthogonal to one another, than in a third spatial direction, which is orthogonal to the first and the second spatial direction and defines an axial direction of the membrane.

A piezoelectric microphone includes a plate, a support portion that is provided around the plate, connection portions that connect the plate and the support portion on two or more sides of the plate, and a detection portion including a lower electrode, a piezoelectric film, and an upper electrode which are stacked in this order. The detection portion is stacked on the connection portion . An inflection point of a cross-sectional deformation curve in a case in which the plate and the connection portion are deformed by sound pressure is present in a region in which the detection portion is not stacked.