Abstract: An acoustic wave device includes: a piezoelectric substrate; electrodes sandwiching the piezoelectric substrate and exciting a thickness shear vibration in the piezoelectric substrate; and an edge region that is a region surrounding a center region of a resonance region, wherein a first region of the edge region is located on both sides of the center region in a first direction substantially parallel to a displacement direction of a thickness shear vibration, a second region of the edge region is located on both sides of the center region in a second direction substantially perpendicular to the first direction, a width of the second region is different from a width of the first region, and acoustic velocities of acoustic waves in the piezoelectric substrate in the first and second regions are less than that in the piezoelectric substrate in the center region.

Abstract: An acoustic wave device includes: a Y-cut X-propagation lithium tantalate substrate having a cut angle of 5° or greater and 18° or less; and a grating electrode that is formed of one or more metal films stacked on the lithium tantalate substrate, a number of the one or more metal films being n (n is a natural number), excites an acoustic wave, and meets a condition: 0.16 ? ? ? ? i = 1 n ? ? ( hi × ? ? ? i ? ? ? 0 ) ? 0.24 ? ? where ?i represents a density of each metal film of the one or more metal films, hi represents a film thickness of the each metal film, ?0 represents a density of Mo, and ? represents a pitch.

Abstract: An acoustic wave device includes: a first resonator that includes a first piezoelectric substance, and first lower and upper electrodes sandwiching the first piezoelectric substance in a direction of a c-axis orientation or a polarization axis of the first piezoelectric substance; and a second resonator that is located closer to a signal input terminal than the first resonator is, is connected in series to the first resonator, includes a second piezoelectric substance, and second lower and upper electrodes sandwiching the second piezoelectric substance so that an electrode in a direction of the c-axis orientation or a polarization axis of the second piezoelectric substance has an electric potential identical to an electric potential of an electrode of the first resonator in the direction of the c-axis orientation or the polarization axis of the first piezoelectric substance, and has an antiresonant frequency less than an antiresonant frequency of the first resonator.

Abstract: An acoustic wave device includes: a piezoelectric substrate; electrodes sandwiching the piezoelectric substrate and exciting a thickness shear vibration in the piezoelectric substrate; and an edge region that is a region surrounding a center region of a resonance region, wherein a first region of the edge region is located on both sides of the center region in a first direction substantially parallel to a displacement direction of a thickness shear vibration, a second region of the edge region is located on both sides of the center region in a second direction substantially perpendicular to the first direction, a width of the second region is different from a width of the first region, and acoustic velocities of acoustic waves in the piezoelectric substrate in the first and second regions are less than that in the piezoelectric substrate in the center region.

Abstract: An acoustic wave device includes: a substrate; an acoustic reflection layer located in or on the substrate and including an air gap, or an acoustic mirror; a piezoelectric film located on the acoustic reflection layer; lower and upper electrodes located on the acoustic reflection layer so as to sandwich the piezoelectric film so that resonance regions are located within the acoustic reflection layer and share the acoustic reflection layer, one of the lower and upper electrodes being divided, another one of the lower and upper electrodes being not divided, the lower and upper electrodes facing each other across the piezoelectric film in each of the resonance regions; and an insertion film located between the lower and upper electrodes, located in at least a part of an outer peripheral region of each of the resonance regions, and being not located in a center region of each of the resonance regions.

Abstract: A response is prevented from being made by a malfunction. A control section (10) includes: a speech sound obtaining section (11) configured to distinctively obtain detected sounds from respective microphones (30), the detected sounds being ones that have been detected by the respective microphones (30); a noise determining section (14) configured to determine whether or not each of the detected sounds is a noise and configured to, in a case where a content of a speech is not recognized from a detected sound, determine that the detected sound is a noise; and a detection control section (17) configured to, in a case where the noise determining section (14) determines that any of the detected sounds is a noise, control at least one of the microphones (30) to stop detecting a sound.

Abstract: An individual-identifying device identifies, from among a plurality of pets, an unidentified pet which has entered an animal toilet 1, with use of evaluation values which are weighted on the basis of (i) a body weight of the unidentified pet and (ii) information indicating the respective strengths of a plurality of signals respectively received from a plurality of ID information transmission devices respectively worn by the plurality of pets.

Abstract: An acoustic wave device includes: a Y-cut X-propagation lithium tantalate substrate having a cut angle of 5° or greater and 18° or less; and a grating electrode that is formed of one or more metal films stacked on the lithium tantalate substrate, a number of the one or more metal films being n (n is a natural number), excites an acoustic wave, and meets a condition: 0.16 ? ? ? ? i = 1 n ? ? ( hi × ? ? ? i ? ? ? 0 ) ? 0.24 ? ? where ?i represents a density of each metal film of the one or more metal films, hi represents a film thickness of the each metal film, ?0 represents a density of Mo, and ? represents a pitch.

Abstract: An acoustic wave resonator includes: a piezoelectric substrate; and an IDT located on the piezoelectric substrate and including a pair of comb-shaped electrodes facing each other, each of the pair of comb-shaped electrodes including a grating electrode exciting an acoustic wave and a bus bar to which the grating electrode is connected, wherein an anisotropy coefficient in a cross region where the grating electrodes of the pair of comb-shaped electrodes cross each other is positive; an anisotropy coefficient in a gap region located between a tip of the grating electrode of one of the pair of comb-shaped electrodes and the bus bar of the other is less than the anisotropy coefficient in the cross region, and an acoustic velocity of an acoustic wave propagating through the gap region is equal to or less than an acoustic velocity of an acoustic wave propagating through the cross region at an antiresonant frequency.

Abstract: An acoustic wave device includes: a piezoelectric thin film resonator that is connected between a first node and a second node; and a resonant circuit that is connected in parallel with the piezoelectric thin film resonator between the first node and the second node, and has a resonant frequency f0 that meets a condition of 2×fa×0.92?f0 where fa represents an antiresonant frequency of the piezoelectric thin film resonator.

Abstract: A filter includes: an input terminal; an output terminal; and a ladder circuit that includes one or more series acoustic wave resonators connected in series between the input terminal and the output terminal and one or more parallel acoustic wave resonators connected in parallel between the input terminal and the output terminal, and in which characteristic impedance of at least one point in a pathway between the input terminal and the output terminal in a passband is greater than at least one of input impedance of the input terminal and output impedance of the output terminal in the passband.

Abstract: An acoustic wave device includes: a substrate; an acoustic reflection layer located in or on the substrate and including an air gap, or an acoustic mirror; a piezoelectric film located on the acoustic reflection layer; lower and upper electrodes located on the acoustic reflection layer so as to sandwich the piezoelectric film so that resonance regions are located within the acoustic reflection layer and share the acoustic reflection layer, one of the lower and upper electrodes being divided, another one of the lower and upper electrodes being not divided, the lower and upper electrodes facing each other across the piezoelectric film in each of the resonance regions; and an insertion film located between the lower and upper electrodes, located in at least a part of an outer peripheral region of each of the resonance regions, and being not located in a center region of each of the resonance regions.

Abstract: An acoustic wave device includes: a piezoelectric thin film resonator that is connected between a first node and a second node; and a resonant circuit that is connected in parallel with the piezoelectric thin film resonator between the first node and the second node, and has a resonant frequency f0 that meets a condition of 2×fa×0.92?f0 where fa represents an antiresonant frequency of the piezoelectric thin film resonator.

Abstract: A filter includes: an input terminal; an output terminal; and a ladder circuit that includes one or more series acoustic wave resonators connected in series between the input terminal and the output terminal and one or more parallel acoustic wave resonators connected in parallel between the input terminal and the output terminal, and in which characteristic impedance of at least one point in a pathway between the input terminal and the output terminal in a passband is greater than at least one of input impedance of the input terminal and output impedance of the output terminal in the passband.

Abstract: An acoustic wave device includes: a first resonator that includes a first piezoelectric substance, and first lower and upper electrodes sandwiching the first piezoelectric substance in a direction of a c-axis orientation or a polarization axis of the first piezoelectric substance; and a second resonator that is located closer to a signal input terminal than the first resonator is, is connected in series to the first resonator, includes a second piezoelectric substance, and second lower and upper electrodes sandwiching the second piezoelectric substance so that an electrode in a direction of the c-axis orientation or a polarization axis of the second piezoelectric substance has an electric potential identical to an electric potential of an electrode of the first resonator in the direction of the c-axis orientation or the polarization axis of the first piezoelectric substance, and has an antiresonant frequency less than an antiresonant frequency of the first resonator.

Abstract: An acoustic wave resonator includes: a piezoelectric substrate; and an IDT located on the piezoelectric substrate and including a pair of comb-shaped electrodes facing each other, each of the pair of comb-shaped electrodes including a grating electrode exciting an acoustic wave and a bus bar to which the grating electrode is connected, wherein an anisotropy coefficient in a cross region where the grating electrodes of the pair of comb-shaped electrodes cross each other is positive; an anisotropy coefficient in a gap region located between a tip of the grating electrode of one of the pair of comb-shaped electrodes and the bus bar of the other is less than the anisotropy coefficient in the cross region, and an acoustic velocity of an acoustic wave propagating through the gap region is equal to or less than an acoustic velocity of an acoustic wave propagating through the cross region at an antiresonant frequency.

Abstract: An acoustic wave device of the present application includes a piezoelectric substrate (14), interdigital transducer electrodes (13) formed on the piezoelectric substrate (14), and an SiO2 film (12) formed so as to cover the electrodes (13). The acoustic wave device also includes a displacement adjustment film (11) formed on the SiO2 film (12), and the displacement adjustment film (11) is formed from a substance whose acoustic velocity is slower than that of the substance forming the SiO2 film (12). According to this configuration, it is possible to suppress unnecessary waves as well as improve temperature characteristics. Also, by mounting such an acoustic wave device in a communication module or communication apparatus, it is possible to achieve an improvement in reliability.

Abstract: A method of manufacturing a spark plug includes the step of adjusting a spark gap in the spark plug. In the step, a ground electrode is repeatedly pressed, by a hammer, toward a center electrode. The hammer operates in a first mode when the size of the spark gap falls in a rough-process range which is above a predetermined value, and in a second mode when the size of the spark gap falls in a finish-process range which is between the predetermined value and a target value less than the predetermined value. The amount of pressing the ground electrode in any press stroke of the hammer in the second mode is less than that in any press stroke of the hammer in the first mode. The amount of pressing the ground electrode in every press stroke of the hammer in the second mode is equal to a fixed value.

Abstract: An acoustic wave device of the present application includes a piezoelectric substrate (14), interdigital transducer electrodes (13) formed on the piezoelectric substrate (14), and an SiO2 film (12) formed so as to cover the electrodes (13). The acoustic wave device also includes a displacement adjustment film (11) formed on the SiO2 film (12), and the displacement adjustment film (11) is formed from a substance whose acoustic velocity is slower than that of the substance forming the SiO2 film (12). According to this configuration, it is possible to suppress unnecessary waves as well as improve temperature characteristics. Also, by mounting such an acoustic wave device in a communication module or communication apparatus, it is possible to achieve an improvement in reliability.

Abstract: A plurality of excitation elements are disposed on two facing sides of a quadrilateral detection range in a non-piezoelectric substrate, and a plurality of receiving elements are disposed on the other two sides of the detection range so as to face the excitation elements respectively. Surface acoustic waves are transmitted from the respective plurality of excitation elements in two diagonal directions of the detection range respectively, and the surface acoustic waves from the two diagonal directions are received by the respective receiving elements, so that a position of an object in contact with the substrate is detected based on received results in the receiving elements.