An IDT electrode of a SAW element has a plurality of first dummy electrodes which extend from the first bus bar to the second bus bar side and have tips which face the tips of the plurality of second electrode fingers through a plurality of first gaps, and a plurality of second dummy electrodes which extend from the second bus bar to the first bus bar side and have tips which face the tips of the plurality of first electrode fingers through a plurality of second gaps. The plurality of first gaps and the plurality of second gaps are arranged to be inclined to the same side relative to the propagation direction of SAW. When the inclination angles of the first gaps and the second gaps relative to the propagation direction are a first angle A and a second angle B, the following are true: 10A26, and 10B26.

An acoustic wave device includes a piezoelectric substrate, an interdigital transducer (IDT) electrode provided on the piezoelectric substrate, and a pair of reflectors provided on both sides of the IDT electrode in a first direction on the piezoelectric substrate, the first direction being a propagation direction of an acoustic wave. The pair of reflectors include a plurality of electrode fingers and a plurality of electrode fingers, respectively, which extend in a second direction, the second direction being perpendicular to the first direction. The electrode finger widths of second end portions are greater than the electrode finger widths of first end portions. The electrode finger width at any given position in the electrode fingers is equal to or greater than the electrode finger width at a position closer than the given position to the first end portions.

An acoustic resonator includes a piezoelectric layer on a substrate and an interdigital electrode structure on the piezoelectric layer. The interdigital electrode structure includes a first bus bar, a second bus bar, a first set of electrode fingers, and a second set of electrode fingers. The first bus bar and the second bus bar extend parallel to one another along a length of the interdigital electrode structure. The first set of electrode fingers are coupled to the first bus bar and extend to a first apodization edge. The second set of electrode fingers are coupled to the second bus bar and extend to a second apodization edge. The first set of electrode fingers and the second set of electrode fingers are interleaved. At least one of the first apodization edge and the second apodization edge provides a wave pattern along the length of the interdigital electrode structure.

An acoustic wave filter device includes at least one series arm resonator and a parallel arm resonator. The series arm resonators and the parallel arm resonator are defined by acoustic wave resonators, an interdigital transducer electrode of the series arm resonators is an apodized interdigital transducer electrode subjected to apodization weighting, in the interdigital transducer electrode of the parallel arm resonator, an intersecting portion includes a central region and low acoustic velocity regions provided at both outer side portions of the central portion, an acoustic velocity of an acoustic wave in the low acoustic velocity region is lower than an acoustic velocity of an acoustic wave in the central region, and a high acoustic velocity region where an acoustic velocity of an acoustic wave is higher than that of the low acoustic velocity region is provided at an outer side portion of each of the low acoustic velocity regions.

Aspects of the disclosure relate to wireless communication, and high-frequency filters with resonators. One aspect is a device including first and second busbars, and electrode fingers coupled between the busbars, with electrode fingers extending different distances toward an opposite busbar such that a second end of each of the electrode fingers collectively form wave shapes. The device further includes pluralities of gap reflectors positioned between the wave shapes and a nearest busbar.

An elastic wave device includes an IDT electrode and a first dielectric layer provided on a piezoelectric substrate. An intersection region where first electrode fingers and second electrode fingers in the IDT electrode overlap each other as viewed from an elastic wave propagation direction includes a center region, a first edge region located on one side of the center region in a direction in which the first electrode fingers and the second electrode fingers extend, and a second edge region located on the other side of the center region in the direction in which the first electrode fingers and the second electrode fingers extend. A mass addition film laminated on the first dielectric layer includes portions of at least two thicknesses.

An acoustic wave device includes: a piezoelectric substrate; a comb-shaped electrode that is located on the piezoelectric substrate and excites an acoustic wave; and a silicon oxide film that is located on the piezoelectric substrate so as to cover the comb-shaped electrode, and has a total concentration of carbon (C), hydrogen (H), nitrogen (N), and fluorine (F) equal to or less than 3.5 atomic %.

An elastic wave resonator including a pair of comb-shaped electrodes and a pair of reflector electrodes formed on a piezoelectric substrate. In one example, the pair of comb-shaped electrodes includes first and second overlapping regions in which electrode fingers of the comb-shaped electrodes interdigitate, the second overlapping region being provided on both outside edges of the first overlapping region in an overlapping width direction, an overlapping width of the first overlapping region being greater than an overlapping width of the second overlapping region, the pair of comb-shaped electrodes being configured to excite a first elastic wave in the first overlapping region and to excite a second elastic wave in the second overlapping region, a frequency of the first elastic wave being higher than a frequency of the second elastic wave.

An elastic wave device includes a piezoelectric film and a high acoustic velocity member in which an acoustic velocity of a bulk wave propagating in the high acoustic velocity member is larger than an acoustic velocity of a main mode elastic wave propagating in the piezoelectric film, the piezoelectric film that is directly or indirectly laminated on the high acoustic velocity member, a first conductive film provided on the piezoelectric film, and a second conductive film that is provided on the piezoelectric film and on at least a portion of the first conductive film. A plurality of IDT electrodes including electrode fingers and busbars are provided on the piezoelectric film, at least electrode fingers of a plurality of IDT electrodes are defined by the first conductive film, and at least a portion of connection wiring with which the plurality of IDT electrodes are connected to each other is defined the second conductive film.

A SAW component and an HF filter with a SAW component are specified, each with reduced disturbances by transversal modes and by SH modes. The SAW component comprises an active area with an internal area between two peripheral areas. The main mode of the SAW component has a lower velocity in the peripheral areas than in the internal area.