Abstract: An acoustic wave device includes first and second piezoelectric layers including lithium niobate or lithium tantalate, a pair of first and second electrodes on a first principal surface of the first piezoelectric layer, and a pair of third and fourth electrodes on a first principal surface of the second piezoelectric layer, wherein the first piezoelectric layer and the first and second electrodes define a first acoustic wave resonator, the second piezoelectric layer and the third and fourth electrodes define a second acoustic wave resonator, and an angle between a crystal orientation of the first piezoelectric layer and a direction perpendicular or substantially perpendicular to a lengthwise direction of the pair of the first and second electrodes is different from an angle between a crystal orientation of the second piezoelectric layer and a direction perpendicular or substantially perpendicular to a lengthwise direction of the pair of the third and fourth electrodes.

Abstract: An acoustic wave device includes a support substrate having a thickness in a first direction, a piezoelectric layer on the support substrate, an interdigital transducer electrode on the piezoelectric layer and including first and second electrode fingers, the first electrode fingers extending in a second direction crossing the first direction, the second electrode fingers extending in the second direction and facing the first electrode fingers in a third direction orthogonal or substantially orthogonal to the second direction, and a reinforcing film on the piezoelectric layer. The support substrate and the piezoelectric layer include a hollow therebetween at a position overlapping the interdigital transducer electrode in the first direction. At least one through hole penetrates the piezoelectric layer at a position not overlapping the interdigital transducer electrode in the first direction, and the through hole communicates with the hollow. The reinforcing film overlaps the hollow in the first direction.

Abstract: An elastic wave device includes a piezoelectric substrate, elastic wave resonators on or in the piezoelectric substrate, and a dielectric film disposed on the piezoelectric substrate and covering the elastic wave resonators. The elastic wave resonators includes respective IDT electrodes on the piezoelectric substrate. When a wavelength specified by an electrode finger pitch of the IDT electrode is denoted as ?, at least two of the elastic wave resonators have the different wavelengths. In two of the elastic wave resonators having different wavelengths, a film thickness of the IDT electrode in the elastic wave resonator having the longer wavelength is not greater than that of the IDT electrode in the elastic wave resonator having the shorter wavelength. Film thicknesses of the IDT electrodes in at least two of the elastic wave resonators are different from each other. The elastic wave device utilizes a Rayleigh wave.

Abstract: A multiplexer includes filters and a common terminal connected to an antenna element by a connection path, a first inductance element being connected between the connection path and a reference terminal. A terminal closer to the antenna element among an input terminal and an output terminal of one filter among the filters is connected to a parallel resonator and is connected to the common terminal with a second inductance element interposed therebetween. A terminal closer to the antenna element among an input terminal and an output terminal of each of other filters other than the one filter among the filters is connected to the common terminal and a series resonator.

Abstract: A multiplexer includes filters and a common terminal connected to an antenna element by a connection path, a first inductance element being connected between the connection path and a reference terminal. A terminal closer to the antenna element among an input terminal and an output terminal of one filter among the filters is connected to a parallel resonator and is connected to the common terminal with a second inductance element interposed therebetween. A terminal closer to the antenna element among an input terminal and an output terminal of each of other filters other than the one filter among the filters is connected to the common terminal and a series resonator.

Abstract: A piezoelectric thin film does not easily generate a heterogeneous phase and exhibits good piezoelectric characteristics. The piezoelectric thin film contains a composition represented by a general formula: (1-n) (K1-xNax)mNbO3-nCaTiO3, wherein m, n, and x in the general formula are within the ranges of 0.87?m?0.97, 0?n?0.065, and 0?x?1.

Abstract: A multiplexer includes a common terminal, a reception terminal, and transmission terminals; a reception filter between the common terminal and the reception terminal; a transmission filter between the common terminal and the transmission terminal; a transmission filter between the common terminal and the transmission terminal; a first inductor connected in series between the common terminal and the reception filter; a second inductor connected between the transmission terminal and the transmission filter; and a third inductor connected between the transmission terminal and the transmission filter. The first inductor and the second inductor couple with each other through a magnetic field, and the first inductor and the third inductor couple with each other through a magnetic field.

Abstract: A multiplexer includes filters and a common terminal connected to an antenna element by a connection path, a first inductance element being connected between the connection path and a reference terminal. A terminal closer to the antenna element among an input terminal and an output terminal of one filter among the filters is connected to a parallel resonator and is connected to the common terminal with a second inductance element interposed therebetween. A terminal closer to the antenna element among an input terminal and an output terminal of each of other filters other than the one filter among the filters is connected to the common terminal and a series resonator.

Abstract: A piezoelectric thin film contains potassium sodium niobate represented by general formula (K1-xNax)NbO3 and CaTiO3, wherein the lattice spacing calculated from the diffraction peak of the (001) plane in an X-ray diffraction profile of the piezoelectric thin film is 3.975 ? or less, and the ratio I101/I001 of the diffraction peak intensity I101 of the (101) plane to the diffraction peak intensity I001 of the (001) plane in the X-ray diffraction profile of the piezoelectric thin film 3 satisfies the relationship log10(I101/I001)??2.10.

Abstract: A multiplexer includes filters and a common terminal connected to an antenna element by a connection path, a first inductance element being connected between the connection path and a reference terminal. A terminal closer to the antenna element among an input terminal and an output terminal of one filter among the filters is connected to a parallel resonator and is connected to the common terminal with a second inductance element interposed therebetween. A terminal closer to the antenna element among an input terminal and an output terminal of each of other filters other than the one filter among the filters is connected to the common terminal and a series resonator.

Abstract: A multiplexer includes a common terminal, a reception terminal, and transmission terminals; a reception filter between the common terminal and the reception terminal; a transmission filter between the common terminal and the transmission terminal; a transmission filter between the common terminal and the transmission terminal; a first inductor connected in series between the common terminal and the reception filter; a second inductor connected between the transmission terminal and the transmission filter; and a third inductor connected between the transmission terminal and the transmission filter. The first inductor and the second inductor couple with each other through a magnetic field, and the first inductor and the third inductor couple with each other through a magnetic field.

Abstract: An elastic wave device includes a piezoelectric substrate, elastic wave resonators on or in the piezoelectric substrate, and a dielectric film disposed on the piezoelectric substrate and covering the elastic wave resonators. The elastic wave resonators includes respective IDT electrodes on the piezoelectric substrate. When a wavelength specified by an electrode finger pitch of the IDT electrode is denoted as ?, at least two of the elastic wave resonators have the different wavelengths. In two of the elastic wave resonators having different wavelengths, a film thickness of the IDT electrode in the elastic wave resonator having the longer wavelength is not greater than that of the IDT electrode in the elastic wave resonator having the shorter wavelength. Film thicknesses of the IDT electrodes in at least two of the elastic wave resonators are different from each other. The elastic wave device utilizes a Rayleigh wave.

Abstract: A multiplexer includes filters and a common terminal connected to an antenna element by a connection path, a first inductance element being connected between the connection path and a reference terminal. A terminal closer to the antenna element among an input terminal and an output terminal of one filter among the filters is connected to a parallel resonator and is connected to the common terminal with a second inductance element interposed therebetween. A terminal closer to the antenna element among an input terminal and an output terminal of each of other filters other than the one filter among the filters is connected to the common terminal and a series resonator.

Abstract: A vibrator in a vibrating gyroscope includes a circular annular portion, a rectangular annular portion, and joining portions. The rectangular annular portion is disposed adjacent to an outer side of the circular annular portion. The joining portions join the circular annular portion and the rectangular annular portion. The rectangular annular portion includes linear beam portions. The joining portions join the circular annular portion and the center portions of the beam portions to each other.

Abstract: An acceleration sensor includes a fixation member, a weight member including a plate with two opposing sides parallel or substantially parallel to an X-direction and two opposing sides parallel to a Y-axis direction in a plan view, the weight member including a cutout extending in a direction about 45° relative to the X and Y axis directions, a vibrating beam linearly extending in the direction about 45° relative to the X and Y axis directions in the plan view, and one end portion is connected to the fixation member and the other end portion is connected to the weight member, the vibrating beam is partly arranged within the cutout and supporting the weight member to be displaceable in a Z-axis direction, a driver disposed on the vibrating beam and vibrating the vibrating beam, and a detector disposed on the vibrating beam and outputting a detection signal that is changed depending on deformation of the vibrating beam.

Abstract: A weight member includes two sides opposite to each other in an X-axis direction when looked at in a plan view. A vibrating beam includes one end portion connected at one location to a fixation member and the other end portion connected at one location to one of the two sides of the weight member in the X-axis direction when looked at in a plan view. The vibrating beam supports the weight member to be displaceable in the X-axis direction. A holding beam includes one end portion connected at one location to the fixation member and the other end portion connected at one location to the other of the two sides of the weight member opposing to each other in the X-axis direction when looked at in a plan view. The holding beam supports the weight member to be displaceable in the X-axis direction. A driver is disposed on the vibrating beam and vibrates the vibrating beam. A detector is disposed on the vibrating beam and configured to output a detection signal changes according to deformation of the vibrating beam.

Abstract: A piezoelectric thin film contains potassium sodium niobate represented by general formula (K1-xNax)NbO3 and CaTiO3, wherein the lattice spacing calculated from the diffraction peak of the (001) plane in an X-ray diffraction profile of the piezoelectric thin film is 3.975 ? or less, and the ratio I101/I001 of the diffraction peak intensity I101 of the (101) plane to the diffraction peak intensity I001 of the (001) plane in the X-ray diffraction profile of the piezoelectric thin film 3 satisfies the relationship log10(I101/I001)??2.10.

Abstract: A piezoelectric thin film does not easily generate a heterogeneous phase and exhibits good piezoelectric characteristics. The piezoelectric thin film contains a composition represented by a general formula: (1-n) (K1-xNax)mNbO3-nCaTiO3, wherein m, n, and x in the general formula are within the ranges of 0.87?m?0.97, 0?n?0.065, and 0?x?1.

Abstract: A vibrator includes first and second circular or substantially circular arc-shaped beam portions, a base end-side weight portion, and a base end-side weight portion joining portion. The end portions of the first and second circular or substantially circular arc-shaped beam portions in an X-axis positive direction face each other across a distance in a Y-axis direction, and the end portions thereof in an X-axis negative direction are joined to each other. The base end-side weight portion is disposed between the first and second circular or substantially circular arc-shaped beam portions. The base end-side weight portion joining portion extends from a joining portion between the first circular or substantially circular arc-shaped beam portion and the second circular or substantially circular arc-shaped beam portion in the X-axis positive direction, and joined to the base end-side weight portion.

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.