The strength of a spurious signal is reduced while maintaining the uniformity of a resonant frequency in an identical elastic wave resonator. An elastic wave resonator (4) includes a piezoelectric body (6), and a plurality of electrode fingers (14, 22) located on the piezoelectric body and arranged in a propagation direction (TD) of an elastic wave. A region in which the plurality of electrode fingers are located includes a first region (24A) and a second region (24B) in a plan view. The plurality of electrode fingers include a first electrode finger group (14A) located in the first region and a second electrode finger group (14B) located in the second region, and a pitch (PA) of the first electrode finger group is different from a pitch (PB) of the second electrode finger group. The first region and the second region have frequency effective-characteristics acting in a direction to cancel out effects on a higher resonant or antiresonant frequency and a lower resonant or antiresonant frequency brought about by a magnitude correlation between the pitches of the first and second electrode finger groups.

A filter device includes a first series line, one or more first parallel lines extending from the first series line, two or more first series IDT electrodes on the first series line, and one or more first parallel IDT electrodes on the one or more first parallel lines. At least one of the two or more first series IDT electrodes is a first-type electrode. A dielectric layer is between the first-type electrode and a substrate. At least one of the two or more first series IDT electrodes except the first-type electrode and the one or more first parallel IDT electrodes is a second-type electrode directly contacting the substrate. A first series IDT electrode of the two or more first series IDT electrodes that has a largest pitch of electrode fingers is the first-type electrode.

A surface acoustic wave resonator comprises a multi-layer piezoelectric substrate including a carrier substrate, a layer of a first dielectric material disposed on the carrier substrate, and a layer of piezoelectric material disposed on the layer of the first dielectric material, interdigital transducer electrodes disposed on the layer of piezoelectric material and including interleaved electrode fingers, and a layer of a second dielectric material disposed on a central interleaved region of the interleaved electrode fingers, gap regions of the interdigital transducer electrodes being either free of the layer of the second dielectric material or having a thinner layer of the second dielectric material than the central interleaved region to reduce spurious signals in an admittance curve of the surface acoustic wave resonator.

An acoustic wave device, a method of manufacture of the same, and a radio frequency filter including the same. The acoustic wave device comprises a multilayer piezoelectric substrate (MPS) including a layer of piezoelectric material having a lower surface disposed on an upper surface of a layer of a dielectric material having a lower surface disposed on an upper surface of a carrier substrate. An interdigital transducer (IDT) is disposed on the multilayer piezoelectric substrate and includes an active region configured to generate an acoustic wave. First and second high impedance portions are included within the multilayer piezoelectric substrate, the first and second high impedance portions each positioned outside the active region of the interdigital transducer and extending in the direction of propagation of the acoustic wave to be generated by the interdigital transducer. The first and second high impedance portions reduce side leakage and suppress transverse modes.

A surface acoustic wave device including a piezoelectric layer, an interdigital transducer electrode over the piezoelectric layer, and a polymeric roof layer arranged over the piezoelectric layer and interdigital transducer electrode. The polymeric roof layer is spaced apart from the piezoelectric layer to define a cavity to accommodate the interdigital transducer electrode. The polymeric roof layer is supported along a span of the polymeric roof layer by at least one pillar. The thermal conductivity of the pillar is greater than the thermal conductivity of the polymeric roof layer. Related wafer-level packages, radio frequency modules and wireless communication devices are also provided.

An improved device delivers a fluid medicament to the subcutaneous tissue of a user. The device is better suited for patients with Parkinson's Disease and other central nervous system disorders, than conventional infusion devices. The device can include a reusable part including a drive component (e.g., motor) and control electronics and a disposable part including a medicament reservoir. Medicament can be evacuated from the medicament reservoir by a plunger assembly that includes a plunger attached to a lead screw that is rotated by a nut, all within the disposable part. The device can be fluidically coupled with the tissue via a flexible cannula. Various embodiments relate to an improved cannula insertion mechanism that delivers the cannula under a force applied by a spring. Various embodiments relate to improved filling of the device, for example, using a vial adapter and an automated filling station.

An improved device delivers a fluid medicament to the subcutaneous tissue of a user. The device is better suited for patients with Parkinson's Disease and other central nervous system disorders, than conventional infusion devices. The device can include a reusable part including a drive component (e.g., motor) and control electronics and a disposable part including a medicament reservoir. Medicament can be evacuated from the medicament reservoir by a plunger assembly that includes a plunger attached to a lead screw that is rotated by a nut, all within the disposable part. The device can be fluidically coupled with the tissue via a flexible cannula. Various embodiments relate to an improved cannula insertion mechanism that delivers the cannula under a force applied by a spring. Various embodiments relate to improved filling of the device, for example, using a vial adapter and an automated filling station.

A multiplexer includes acoustic wave filters that are electrically connected to a common connection terminal. In a first transmission-side filter of the acoustic wave filters, a series arm resonator closest to the common connection terminal includes acoustic wave resonators that are electrically connected in series and capacitance elements that are electrically connected between at least one of signal paths electrically connecting the acoustic wave resonators to each other and a reference terminal.

A multiplexer includes a common terminal, a first terminal, a second terminal, a first filter device including acoustic wave resonators including series resonators and parallel resonators, an inductor provided between an acoustic wave resonator and the first terminal, and a second filter device. The first filter device further includes a first ground terminal to which a parallel resonator is electrically connected, a second ground terminal to which the parallel resonators are electrically connected, and a wiring provided between the inductor and an acoustic wave resonator. In the first filter device, the wiring is electrically connected to the first ground terminal, and the first ground terminal is not connected to the second ground terminal.

A longitudinally coupled resonator acoustic wave filter including IDT electrodes including a first IDT electrode and a second IDT electrode, and first and second reflectors, in which the IDT electrodes have respective hot-side comb-shaped electrodes and respective ground-side comb-shaped electrodes, the hot-side comb-shaped electrodes of the first IDT electrodes are electrically connected to at least one of the first and second reflectors, the second IDT electrodes are between the IDT electrode and the first reflector and between the IDT electrode and the second reflector respectively, the hot-side comb-shaped electrodes of the IDT electrodes are connected to one of an input end and an output end, and the hot-side comb-shaped electrodes of the IDT electrodes are connected to the other of the input end and the output end.