Abstract: A piezoelectric transformer that includes a vibration portion assembly having an output electrode, an output-side intermediate electrode, an input-side intermediate electrode, and an input electrode. The vibration portion assembly includes n vibration portions. The input electrode includes one to n input electrode pieces. The output electrode includes one to n output electrode pieces. Wiring lines are arranged such that voltages of opposite phases can be respectively applied to a first input electrode piece group of the input electrode pieces corresponding to odd-numbered vibration portions, and a second input electrode piece group of the input electrode pieces corresponding to even-numbered vibration portions. The second output electrode piece and the first output-side intermediate electrode piece are superposed with each other in the thickness direction.

Abstract: A piezoelectric transformer that includes a base and an upper layer supported by the base. The upper layer includes a first piezoelectric layer that includes the portion of the upper layer that is interposed between an output electrode and an intermediate electrode, and a second piezoelectric layer that is superposed with the first piezoelectric layer and includes the portion of the upper layer interposed between the intermediate electrode and an input electrode in at least n vibration portions. Moreover, the input electrode includes multiple input electrode pieces and the output electrode includes multiple output electrode pieces. In addition, wiring lines are routed such that voltages of opposite phases can be respectively applied to a first input electrode piece group and a second input electrode piece group with the potential of the intermediate electrode serving as a reference.

Abstract: A piezoelectric device that includes a base member having an opening therein and an upper layer supported by the base member. The upper layer includes a vibration portion at a location corresponding to the opening in the base member. The vibration portion includes a lower electrode, an intermediate electrode and an upper electrode that are spaced apart from one another in a thickness direction of the piezoelectric device. The upper layer includes a first piezoelectric layer disposed so as to be at least partially sandwiched between the lower electrode and the intermediate electrode, and a second piezoelectric layer disposed so as to overlap with the first piezoelectric layer and so as to be at least partially sandwiched between the intermediate electrode and the upper electrode. The first piezoelectric layer and the second piezoelectric layer are different in relative permittivity in the thickness direction of the piezoelectric device.

Abstract: A method for manufacturing a piezoelectric device that includes a substrate and a vibration portion that can include a membrane or a beam that is directly or indirectly supported by the substrate and arranged above the substrate. Moreover, the vibration portion includes a piezoelectric layer and the method includes forming the vibration portion and adjusting a resonance frequency of the vibration portion by locally subjecting a region including the vibration portion to heat treatment.

Abstract: A method for manufacturing a piezoelectric device that includes a substrate, a piezoelectric layer directly or indirectly supported by the substrate and arranged above the substrate, a heater, and a heater electrode for driving the heater. Moreover, the method includes forming the piezoelectric layer, the heater, and the heater electrode and subjecting the piezoelectric device to heat treatment with heat generated from the heater by driving the heater by feeding electric power to the heater electrode.

Abstract: A piezoelectric device that includes a substrate defining an opening therein; a piezoelectric layer arranged above the substrate such that at least part of the piezoelectric layer extends over the opening and forms a membrane part that is not superimposed with the substrate; a lower electrode arranged below the piezoelectric layer in at least the membrane part; and an upper electrode that is arranged above the piezoelectric layer so as to face at least part of the lower electrode with the piezoelectric layer interposed therebetween in the membrane part. A heater is arranged above the piezoelectric layer so as to be separate from the upper electrode or at least part of the upper electrode doubles as a heater.

Abstract: An electroacoustic transducer includes an ultrasonic element that includes a diaphragm and a support frame, a case body that accommodates the ultrasonic element, and fixing portions that join the support frame portion to a bottom plate portion of the case body. First and second main surfaces of the diaphragm face top and bottom plate portions of the case body, respectively, and a sound hole is provided in the case body. The fixing portions are partially provided along the circumferential direction of the support frame such that a space between the second main surface and the bottom plate portion communicates with a space around the ultrasonic element, and an acoustic path connecting the first main surface and the second main surface and the sound hole is provided in the case body. The fixing portions are defined by a die bonding agent including spherical spacers.

Abstract: A piezoelectric transformer that includes a vibration portion assembly having an output electrode, an output-side intermediate electrode, an input-side intermediate electrode, and an input electrode. The vibration portion assembly includes n vibration portions. The input electrode includes one to n input electrode pieces. The output electrode includes one to n output electrode pieces. Wiring lines are arranged such that voltages of opposite phases can be respectively applied to a first input electrode piece group of the input electrode pieces corresponding to odd-numbered vibration portions, and a second input electrode piece group of the input electrode pieces corresponding to even-numbered vibration portions. The second output electrode piece and the first output-side intermediate electrode piece are superposed with each other in the thickness direction.

Abstract: A piezoelectric transformer that includes a base and an upper layer supported by the base. The upper layer includes a first piezoelectric layer that includes the portion of the upper layer that is interposed between an output electrode and an intermediate electrode, and a second piezoelectric layer that is superposed with the first piezoelectric layer and includes the portion of the upper layer interposed between the intermediate electrode and an input electrode in at least n vibration portions. Moreover, the input electrode includes multiple input electrode pieces and the output electrode includes multiple output electrode pieces. In addition, wiring lines are routed such that voltages of opposite phases can be respectively applied to a first input electrode piece group and a second input electrode piece group with the potential of the intermediate electrode serving as a reference.

Abstract: An electroacoustic transducer includes an ultrasonic element that includes a diaphragm and a support frame, a case body that accommodates the ultrasonic element, and fixing portions that join the support frame portion to a bottom plate portion of the case body. First and second main surfaces of the diaphragm face top and bottom plate portions of the case body, respectively, and a sound hole is provided in the case body. The fixing portions are partially provided along the circumferential direction of the support frame such that a space between the second main surface and the bottom plate portion communicates with a space around the ultrasonic element, and an acoustic path connecting the first main surface and the second main surface and the sound hole is provided in the case body. The fixing portions are defined by a die bonding agent including spherical spacers.

Abstract: A thermal infrared sensor for gas measurement including a sensing element. The sensing element includes a thermal detection layer that outputs an electric signal based on a temperature change, a light-receiving surface electrode disposed on a light-receiving surface of the thermal detection layer, and a back electrode disposed on the thermal detection layer opposite the light-receiving surface electrode. The light-receiving surface electrode has a periodic structure configured to selectively absorb infrared light having an absorption wavelength of a sample gas.

Abstract: A thermal-type flow-rate sensor includes a substrate and a detection unit that is supported by the substrate and at least an upper surface of which is exposed to a flow of a fluid. The detection unit includes: an insulating layer, a heating element arranged on an upper surface of the insulating layer, an upstream temperature measurement element that is arranged on the upper surface of the insulating layer upstream of the heating element in the flow direction that includes a pyroelectric layer, and a downstream temperature measurement element arranged on the upper surface of the insulating layer so as to be positioned downstream of the heating element in the flow direction and that includes a pyroelectric layer.

Abstract: A piezoelectric device that includes a base member having an opening therein and an upper layer supported by the base member. The upper layer includes a vibration portion at a location corresponding to the opening in the base member. The vibration portion includes a lower electrode, an intermediate electrode and an upper electrode that are spaced apart from one another in a thickness direction of the piezoelectric device. The upper layer includes a first piezoelectric layer disposed so as to be at least partially sandwiched between the lower electrode and the intermediate electrode, and a second piezoelectric layer disposed so as to overlap with the first piezoelectric layer and so as to be at least partially sandwiched between the intermediate electrode and the upper electrode. The first piezoelectric layer and the second piezoelectric layer are different in relative permittivity in the thickness direction of the piezoelectric device.

Abstract: A method for manufacturing a piezoelectric device that includes a substrate, a piezoelectric layer directly or indirectly supported by the substrate and arranged above the substrate, a heater, and a heater electrode for driving the heater. Moreover, the method includes forming the piezoelectric layer, the heater, and the heater electrode and subjecting the piezoelectric device to heat treatment with heat generated from the heater by driving the heater by feeding electric power to the heater electrode.

Abstract: A method for manufacturing a piezoelectric device that includes a substrate and a vibration portion that can include a membrane or a beam that is directly or indirectly supported by the substrate and arranged above the substrate. Moreover, the vibration portion includes a piezoelectric layer and the method includes forming the vibration portion and adjusting a resonance frequency of the vibration portion by locally subjecting a region including the vibration portion to heat treatment.

Abstract: A thermal infrared sensor for gas measurement including a sensing element. The sensing element includes a thermal detection layer that outputs an electric signal based on a temperature change, a light-receiving surface electrode disposed on a light-receiving surface of the thermal detection layer, and a back electrode disposed on the thermal detection layer opposite the light-receiving surface electrode. The light-receiving surface electrode has a periodic structure configured to selectively absorb infrared light having an absorption wavelength of a sample gas.

Abstract: A piezoelectric device that includes a substrate defining an opening therein; a piezoelectric layer arranged above the substrate such that at least part of the piezoelectric layer extends over the opening and forms a membrane part that is not superimposed with the substrate; a lower electrode arranged below the piezoelectric layer in at least the membrane part; and an upper electrode that is arranged above the piezoelectric layer so as to face at least part of the lower electrode with the piezoelectric layer interposed therebetween in the membrane part. A heater is arranged above the piezoelectric layer so as to be separate from the upper electrode or at least part of the upper electrode doubles as a heater.

Abstract: A piezoelectric device that includes a support layer, a lower electrode, a piezoelectric film and an upper electrode on a substrate. In the substrate, a first opening is provided that penetrates through at least part of the substrate in a thickness direction of the substrate. A second opening that faces the support layer and the first opening is provided above the first opening. An opening area of the first opening is smaller than an opening area of the second opening.

Abstract: A thermal-type flow-rate sensor includes a substrate and a detection unit that is supported by the substrate and at least an upper surface of which is exposed to a flow of a fluid. The detection unit includes: an insulating layer, a heating element arranged on an upper surface of the insulating layer, an upstream temperature measurement element that is arranged on the upper surface of the insulating layer upstream of the heating element in the flow direction that includes a pyroelectric layer, and a downstream temperature measurement element arranged on the upper surface of the insulating layer so as to be positioned downstream of the heating element in the flow direction and that includes a pyroelectric layer.

Abstract: A piezoelectric device that includes a piezoelectric film, which is formed by a sputtering method and which has a columnar structure, and electrodes disposed in contact with the piezoelectric film. The piezoelectric film has a composition containing an element which can substitute Nb and has an oxidation number of 2 or more and less than 5 when oxidized in a proportion of 3.3 mol or less relative to 100 mol of potassium sodium niobate represented by a general formula (K1-xNax)NbO3, where 0<x<1.