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: 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 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 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 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: 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 an outer base, a protruding base, and only one cantilevered portion. A protruding base includes a protrusion and a tip portion. The protrusion protrudes from an internal circumferential surface of the outer base toward a center of a ring shape. The tip portion is connected to the protrusion and located at the center. The cantilevered portion is connected to the tip portion, and extends while being spaced apart from the protrusion. The cantilevered portion includes a fixed end portion and a free periphery. The fixed end portion is connected to the tip portion. The free periphery is located along the internal circumferential surface. The protrusion is located between a first end and a second end of the free periphery.

Abstract: In a piezoelectric device, a cantilever portion includes a fixed edge portion and a free edge portion. A plate-shaped portion includes a facing edge portion, a support edge portion, a first lateral support edge portion, and a second lateral support edge portion. The facing edge portion faces the free edge portion. The support edge portion is on an opposite side from the facing edge portion in an extension direction of the cantilever portion. The plate-shaped portion is connected to an inner surface at at least a portion of the support edge portion, at least a portion of the first lateral support edge portion, and at least a portion of the second lateral support edge portion.

Abstract: A piezoelectric device includes a beam portion with a fixed end portion and a free end portion opposite to the fixed end portion. The beam portion extends from the fixed end portion towards the free end portion. The beam portion includes a multilayer body including a piezoelectric layer and first and second electrode layers. A base is connected with the fixed end portion of the beam portion. As viewed from a layering direction of the multilayer body, the base surrounds the beam portion at an interval from the beam portion except for the fixed end portion. As viewed from the layering direction, an average of a dimension of a width of the beam portion in an orthogonal or substantially orthogonal direction to an extension direction of the beam portion is greater than a maximal dimension of a length thereof in the extension direction.

Abstract: A piezoelectric device includes a substrate, a piezoelectric element, and a lid. The piezoelectric element includes a base portion and a membrane portion. The base portion is on a first main surface and has an annular outer shape when viewed from a normal direction of the first main surface. The membrane portion is at an inner side portion of the base portion when viewed from the normal direction. The lid is on the first main surface, covers the piezoelectric element, and is spaced apart from the piezoelectric element on the first main surface side. In the substrate, a first through hole extending from the first main surface to a second main surface is facing the membrane portion. The membrane portion includes a through slit.

Abstract: A piezoelectric device includes a substrate including a first main surface and a second main surface. A piezoelectric element is on the first main surface. A cover on the first main surface. The cover covers the piezoelectric element and is spaced apart from piezoelectric element on the first main surface side. The piezoelectric element includes a base portion and a membrane portion. The base portion is on the first main surface and has an annular external shape when viewed from the first main surface side. The membrane portion is inside the annular base portion when viewed from the first main surface side. The cover includes a first through hole. The substrate includes a second through hole facing the membrane portion and extends between the first main surface and the second main surface.

Abstract: An object of the disclosure is to achieve a current-driven display device able to compensate for a variation in threshold voltage of a drive transistor without causing a variation in luminance. A pixel circuit includes an organic EL element; a drive transistor; a first capacitor having a first electrode to be supplied with a reference voltage during a data writing period and a second electrode to be supplied with a data voltage-during a data writing period; a second capacitor having a first electrode connected to the first electrode of the first capacitor and a second electrode connected to a first conduction terminal of the drive transistor; and a short-circuit control transistor having a gate terminal to be supplied with a light emission control signal-, which becomes active during a light emission period, a first conduction terminal connected to the first electrode of the first capacitor, and a second conduction terminal connected to the second electrode of the first capacitor.

Abstract: The present application discloses a current-driven display device which employs internal compensation, by which a non-emission period can be shortened without causing the luminance of display elements to be unstable. During a period in which a voltage on a data signal line Dj is written to a pixel circuit, transistors M4 and M6 are controlled to be in an OFF state, and transistors M2, M3, and M5 are controlled to be in an ON state. As a result, a drive transistor M1 is diode-connected, a source terminal thereof is disconnected from a high-level power line ELVDD, and a gate terminal thereof and an anode of an organic EL element OLED are connected to an initialization voltage supply line Vini. Consequently, a gate voltage Vg of the drive transistor M1 and an anode voltage Va of the organic EL element OLED are initialized, and first and second capacitors C1 and C2 respectively hold a voltage corresponding to the voltage on the data signal line Dj and a threshold voltage of the drive transistor M1.

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 piezoelectric transducer includes beam portions supported by a base portion at an end portion and extending in a direction away from the base portion above the base portion. Each beam portion includes a piezoelectric layer, an upper electrode layer on an upper side of the piezoelectric layer, and a lower electrode layer facing at least a portion of the upper electrode layer with the piezoelectric layer interposed therebetween. A fixing portion is disposed on the beam portion to sandwich the end portion of each beam portion between the fixing portion and the base portion. The fixing portion overlaps at least a portion of the base portion in an up-down direction, and extends to protrude from the base portion in an extending direction of the beam portion.

Abstract: The present application discloses a current-driven display device which employs internal compensation, by which a non-emission period can be shortened without causing the luminance of display elements to be unstable. During a period in which a voltage on a data signal line Dj is written to a pixel circuit, transistors M4 and M6 are controlled to be in an OFF state, and transistors M2, M3, and M5 are controlled to be in an ON state. As a result, a drive transistor M1 is diode-connected, a source terminal thereof is disconnected from a high-level power line ELVDD, and a gate terminal thereof and an anode of an organic EL element OLED are connected to an initialization voltage supply line Vini. Consequently, a gate voltage Vg of the drive transistor M1 and an anode voltage Va of the organic EL element OLED are initialized, and first and second capacitors C1 and C2 respectively hold a voltage corresponding to the voltage on the data signal line Dj and a threshold voltage of the drive transistor M1.

Abstract: An object of the disclosure is to achieve a current-driven display device able to compensate for a variation in threshold voltage of a drive transistor without causing a variation in luminance. A pixel circuit includes an organic EL element; a drive transistor; a first capacitor having a first electrode to be supplied with a reference voltage during a data writing period and a second electrode to be supplied with a data voltage-during a data writing period; a second capacitor having a first electrode connected to the first electrode of the first capacitor and a second electrode connected to a first conduction terminal of the drive transistor; and a short-circuit control transistor having a gate terminal to be supplied with a light emission control signal, which becomes active during a light emission period, a first conduction terminal connected to the first electrode of the first capacitor, and a second conduction terminal connected to the second electrode of the first capacitor.