Abstract: A piezoelectric device includes a connecting section connecting a pair of beam sections adjacent to each other. The connecting section is connected to one of the pair of beam sections at a first end portion. The connecting section is connected to another of the pair of beam sections at a second end portion. The second end portion faces the first end portion in a direction in which the pair of beam sections are aligned. A second coupling portion is located along a first coupling portion. The connecting section includes only one first end portion. The connecting section includes only one second end portion. Each of the first end portion and the second end portion is closer to a tip end portion than to a fixed end portion of each of the pair of beam sections.

Abstract: A transducer includes a base, beams, and a coupler. The beams each include a piezoelectric layer, a first electrode layer, and a second electrode layer. The coupler is fitted in slits between adjacent beams to define a connection between the beams. The coupler extends from an upper portion of the base into each of the slits without a break. A Young's modulus of the material of the coupler is lower than a Young's modulus of the material of the piezoelectric layer. A maximum thickness of the coupler in the upper portion of the base in the direction of the central axis of the base is greater than a thickness of each of the beams.

Abstract: A piezoelectric device includes a base portion and a membrane portion. The membrane portion is indirectly supported by the base portion, and is located on the upper side relative to the base portion. The membrane portion includes a plurality of layers. The membrane portion does not overlap with the base portion, and includes a single crystal piezoelectric layer, an upper electrode layer, and a lower electrode layer. The membrane portion is provided with a through-groove penetrating in the up-down direction. The through-groove includes a first step portion provided in the thickest layer among the plurality of layers defining the membrane portion. The width of the through-groove is narrower on a lower side than on an upper side with the first step portion as a boundary.

Abstract: A piezoelectric transducer includes beam portions each with a fixed end portion and extending in a direction away from the fixed end portion. A base portion is connected to the fixed end portion of each of the beam portions. The beam portions extends in a same plane, and respective extending directions of at least two beam portions are different from each other. The beam portions each include a single crystal piezoelectric layer having a polarization axis in a same direction, an upper electrode layer, and a lower electrode layer. A polarization axis has a polarization component in the plane. An axial direction of an orthogonal axis that is orthogonal to the polarization axis and extends in the above-described plane intersects with an extending direction of each of the plurality of beam portions.

Abstract: A MEMS device includes a piezoelectric layer made of a piezoelectric single crystal, a first electrode on a first surface of the piezoelectric layer, and a first layer covering the first surface of the piezoelectric layer. At least a portion of the piezoelectric layer is included in a membrane portion. The first electrode is covered with the first layer and includes a recess. The piezoelectric layer includes a through hole that passes through the piezoelectric layer between a surface of the piezoelectric layer, which is opposite to the first direction, and the recess at a position corresponding to at least a portion of the first electrode.

Abstract: A piezoelectric device includes a membrane portion and a piezoelectric layer made of single crystal of a piezoelectric body. At least a portion of the piezoelectric layer is included in the membrane portion. An electrode is provided on a surface of the piezoelectric layer in the membrane portion. The piezoelectric layer includes a first polarization region in a first polarization state and a second polarization region in a second polarization state, and the first polarization region and the second polarization region are spaced apart from each other in a thickness direction or an in-plane direction.

Abstract: A MEMS device includes a membrane portion, a piezoelectric layer made of a piezoelectric single crystal, a first electrode on a first surface of the piezoelectric layer, a second electrode on a second surface of the piezoelectric layer opposite to the first direction, and a first layer covering the first surface of the piezoelectric layer. At least a portion of the piezoelectric layer is included in the membrane portion. Each of the first electrode and the second electrode has a tapered cross-sectional shape with a width which decreases with increasing distance from the piezoelectric layer on a cross section along a plane vertical to the surface in the first direction.

Abstract: A piezoelectric device includes a piezoelectric single crystal body with a homogeneous polarization state and of which at least a portion flexurally vibrates, an upper electrode on an upper surface of the piezoelectric single crystal body, a lower electrode on a lower surface of the piezoelectric single crystal body, and a supporting substrate below the piezoelectric single crystal body. A recess extends from a lower surface of the supporting substrate toward the lower surface of the piezoelectric single crystal body.

Abstract: A transducer includes a first connection portion connecting a first tip and a second tip to each other. The first connection portion is surrounded by a split slit connecting a center of the first tip, a center of a base, and a center of the second tip, the first tip, and the second tip.

Abstract: A piezoelectric device includes a base and a laminated portion. The laminated portion includes, at least above a recess, a piezoelectric layer, a pair of electrode layers to apply a voltage to the piezoelectric layer, and a membrane covering the recess. The membrane includes a piezoelectric membrane, in the piezoelectric layer, that swells on at least one of a side of the recess and a side opposite to the side of the recess.

Abstract: A piezoelectric device includes a membrane portion including a through slot extending through the membrane portion in an up-down direction. A width of the through slot in a single crystal piezoelectric material layer becomes narrower as the through slot extends downward. In the single crystal piezoelectric material layer and a reinforcing layer, a maximum width of the through slot in a layer located on a bottom side is smaller than a minimum width of the through slot in a layer located on a top side.

Abstract: A layered portion includes, at least above an opening, a first single-crystal piezoelectric body layer, a second single-crystal piezoelectric body layer, an intermediate electrode layer, a lower electrode layer, and an upper electrode layer. The first single-crystal piezoelectric body layer includes a material that produces a difference in etching rate between a positive side and a negative side of a polarization charge. The polarization charge of the first single-crystal piezoelectric body layer is negative on a side of the intermediate electrode layer and positive on a side of the lower electrode layer.

Abstract: In a piezoelectric device, electrode layers are spaced apart from each other in the direction of the normal thereto. A first piezoelectric layer is interposed between two electrode layers of electrode layers in the direction of the normal. A second piezoelectric layer is provided on an opposite side of the first piezoelectric layer from a base portion. The second piezoelectric layer is interposed between two electrode layers of the electrode layers in the direction of the normal. The half-width of a rocking curve measured by X-ray diffraction for a lattice plane of the first piezoelectric layer substantially parallel to a first main surface is smaller than a half-width for the second piezoelectric layer. The piezoelectric constant of a material defining the first piezoelectric layer is smaller than the piezoelectric constant of a material defining the second piezoelectric layer.

Abstract: A piezoelectric device includes a connection section including a first coupling portion, a second coupling portion, and a bridging portion. The first coupling portion extends along a slit and is connected to one of a pair of beam sections. The second coupling portion extends along the slit and is connected to another of the pair of beam sections. The bridging portion is located between the slit and an opening and is connected to both of the first coupling portion and the second coupling portion. The beam sections are connected to each other in a circumferential direction of a base having an annular shape via the connecting section while each of the beam sections is interposed between the slits extending in intersecting directions.

Abstract: An ultrasonic transducer includes first and second acoustic transducers and a housing with a bottomed tubular shape. The second acoustic transducer includes an annular section supporting a second membrane section and contacting an entire periphery of the second membrane section, and an acoustic matching plate facing the second membrane section and spaced apart from the second membrane section. The acoustic matching plate is connected to a surrounding wall portion defining a sealed space with the housing. An ultrasonic transmission path sandwiched between the first membrane section and the second membrane section is provided in the sealed space. A maximum inner width of the ultrasonic transmission path is smaller than a maximum inner width of the surrounding wall portion.

Abstract: In a piezoelectric device, when viewed in a direction perpendicular to one main surface, an outer shape of a recess is a polygonal shape or a circular shape. When n represents a number of sides of the polygonal shape, r represents a radius of a circumscribed circle of an imaginary regular polygon including n sides with a length identical to a length of a shortest of the sides, and d represents a maximum thickness of a membrane portion, which is located above the recess, of a multilayer portion, r?197.7dn?0.6698 when 3?n?7, and r?52.69d when 8?n or when the outer shape of the recess is a circular shape.

Abstract: In a piezoelectric device, a layered portion includes, at a position at least above a recess, a single crystal piezoelectric layer and a pair of electrode layers to apply voltage to the single crystal piezoelectric layer. At least a portion of the pair of electrode layers includes a lower electrode layer extending along a surface of the single crystal piezoelectric layer, the surface being closer to a base. The lower electrode layer is present only inside the recess.

Abstract: A piezoelectric device includes a piezoelectric body at least a portion of which can bend and vibrate, an upper electrode on an upper surface of the piezoelectric body and in which distortion of a crystal lattice is reduced as a distance from the upper surface of the piezoelectric body increases, a lower electrode on a lower surface of the piezoelectric body and in which distortion of a crystal lattice is reduced as a distance from the upper surface of the piezoelectric body increases, and a support substrate below the piezoelectric body, in which a recess extending from a lower surface of the support substrate toward the lower surface of the piezoelectric device is provided.

Abstract: A piezoelectric device includes a connecting section connecting a pair of beam sections adjacent to each other. The connecting section is connected to one of the pair of beam sections at a first end portion. The connecting section is connected to another of the pair of beam sections at a second end portion. The second end portion faces the first end portion in a direction in which the pair of beam sections are aligned. A second coupling portion is located along a first coupling portion. The connecting section includes only one first end portion. The connecting section includes only one second end portion. Each of the first end portion and the second end portion is closer to a tip end portion than to a fixed end portion of each of the pair of beam sections.

Abstract: A vibrating device includes a tubular vibrating body and a lens cover coupled to a first surface of the tubular vibrating body. The tubular vibrating body includes a tubular member and piezoelectric vibrators. The lens cover includes a mode changing coupler and a light transmitting body unit disposed in front of a lens of a camera. The mode changing coupler includes a thin portion having a thickness smaller than a thickness of the tubular member.