Abstract: To provide an optical filter which can sufficiently reduce transmission of the red component. The optical filter 10 includes a first filter 20, a second filter 30 formed on a first surface 20A of the first filter 20, and a third filter 40 formed on a second surface 20B of the first filter 20. The optical filter 10 has cutoff characteristics in a first band A1 defined from a long-wavelength side in the visible region to the near-infrared region and in a third band A3 defined on the long-wavelength side relative to the first band, and has transmission characteristics in a second band A2 defined between the first band A1 and the third band A3. In the first band A1, a cutoff band in which a transmittance is 5% or lower is set to a bandwidth of at least 100 nm.

Abstract: An object is to provide a frequency adjustment method for a piezoelectric resonator device that is applicable to a microminiaturized device and that can adjust the frequency without deteriorating the accuracy of frequency adjustment. A frequency adjustment method for a tuning-fork quartz resonator is applicable to a tuning-fork quartz resonator that includes a tuning-fork quartz resonator piece having a pair of resonator arms 31, 32 and metallic adjustment films W formed on the resonator arms. The frequency adjustment method adjusts the frequency by reduction of a mass of the metallic adjustment films W. The frequency adjustment method includes: a rough adjustment step for roughly adjusting the frequency by partially thinning or removing the metallic adjustment films W; and a fine adjustment step for finely adjusting the frequency by at least partially thinning or removing products W1, W2 derived from the metallic adjustment film W during the rough adjustment step.

Abstract: An AT-cut crystal resonator plate includes: a vibrating part having a rectangular shape in plan view that is disposed on a center of the AT-cut crystal resonator plate and that has excitation electrodes respectively formed on a first and a second main surfaces; a cut-out part having a rectangular shape in plan view that is formed along an outer periphery of the vibrating part; an external frame part having a rectangular shape in plan view that is formed along an outer periphery of the cut-out part; and a connecting part that connects the vibrating part to the external frame part and that extends, in a Z? axis direction of the vibrating part, from one end part of a side of the vibrating part along an X axis direction. The connecting part includes wide parts whose widths gradually increase only toward the external frame part.

Abstract: Hermeticity of an annular sealing bonding material to seal a vibrating part is improved. In the crystal resonator 10, a resonator-plate-side first bonding pattern 251 annularly formed on a crystal resonator plate 2 is bonded to a sealing-member-side first bonding pattern 321 annularly formed on a first sealing member 3, and a resonator-plate-side second bonding pattern 252 annularly formed on the crystal resonator plate 2 is bonded to a sealing-member-side second bonding pattern 421 annularly formed on a second sealing member 4. Thus, annular bonding materials 11a and 11b, which hermetically seal a vibrating part 22 causing piezoelectric resonance, are formed. Inner peripheral edge parts 111a and 111b and outer peripheral edge parts 112a and 112b of the bonding materials 11a and 11b are formed denser than intermediate parts 113a and 113b between the inner and outer peripheral edge parts 111a and 112a, and between the inner and outer peripheral edge parts 111b and 112b.

Abstract: A crystal resonator includes: a crystal resonator plate; a first sealing member that covers a first excitation electrode of the crystal resonator plate; and a second sealing member that covers a second excitation electrode of the crystal resonator plate and includes a first external electrode terminal and a second external electrode terminal to be bonded to a circuit board using a flowable conductive bonding material. The second sealing member includes a second through hole and a third through hole that pass through between a first main surface and a second main surface on which the first external electrode terminal and the second external electrode terminal are formed. The second through hole and the third through hole include: respective through electrodes for conduction between electrodes formed on the first main surface and the second main surface; and respective through parts.

Abstract: A crystal resonator element 2 has excitation electrodes 23a, 23b formed on front and back main surfaces of a crystal resonator plate. Each of the excitation electrodes is made of a ternary alloy containing silver as a major component, a first additive, and a second additive. The first additive is a metal element having a lower sputtering yield than silver and being resistant to corrosion in an etching liquid. The second additive is an element for forming a solid solution with silver. Outer peripheries of the excitation electrodes are first additive-rich regions 9 in which the first additive is rich.

Abstract: A crystal resonator (101) includes: a crystal resonator plate (2); a first sealing member (3); a second sealing member (4); and an internal space (13) hermetically sealing a vibrating part (22) of the crystal resonator plate (2). The crystal resonator plate (2) includes: the vibrating part (22); an external frame part (23) surrounding an outer periphery of the vibrating part (22); and a connecting part (24) connecting the vibrating part (22) to the external frame part (23). A first extraction electrode (223) drawn from a first excitation electrode (221) is formed on a first main surface of the connecting part (24) while a second extraction electrode (224) drawn from a second excitation electrode (222) is formed on a second main surface thereof. A wiring pattern (33) connected to the first extraction electrode (223) is formed on a second main surface (312) of the first sealing member (3).

Abstract: This piezoelectric wafer has: a piezoelectric vibration piece; a frame portion that supports the piezoelectric vibration piece; and a coupling portion that couples the piezoelectric vibration piece to the frame portion. A pair of first and second metal bumps is formed in juxtaposition on the piezoelectric vibration piece. The coupling portion has slits extending in its width direction except in a bridge, i.e., a part of the coupling portion in its width direction. An end in the width direction of the bridge is distantly spaced from the first and second metal bumps both in a direction perpendicular to the width direction of the coupling portion with no overlap with these metal bumps.

Abstract: This piezoelectric wafer has: a piezoelectric vibration piece; a frame portion that supports the piezoelectric vibration piece; and a coupling portion that couples the piezoelectric vibration piece to the frame portion. The piezoelectric vibration piece is broken off at the coupling portion and separated from the piezoelectric wafer. On front and back surfaces of the coupling portion, grooved slits extending along a width direction of the coupling portion are formed except for parts of the coupling portion in the width direction. An electrode on at least one of front and back surfaces of the piezoelectric vibration piece is extracted to a frame-portion side of the piezoelectric wafer by way of the part of the coupling portion in the width direction.

Abstract: A crystal resonator element 2 has excitation electrodes 23a, 23b formed on front and back main surfaces of a crystal resonator plate. Each of the excitation electrodes is made of a ternary alloy containing silver as a major component, a first additive, and a second additive. The first additive is a metal element having a lower sputtering yield than silver and being resistant to corrosion in an etching liquid. The second additive is an element for forming a solid solution with silver. Outer peripheries of the excitation electrodes are first additive-rich regions 9 in which the first additive is rich.

Abstract: A piezoelectric resonator device adapted to miniaturization while saving a region to be bonded to an external circuit board is provided, which includes an external connection terminal with a highly recognizable distinguishing mark. A crystal resonator 1 includes: a base 2 having a substrate 20, a first frame 21 and a second frame 22; a crystal resonator element 3 housed in a first recessed portion E1; a thermistor 4 housed in a second recessed portion E2; and a lid 5 hermetically sealing the first recessed portion E2. L-shaped external connection terminals 9a to 9d are respectively formed at four corners of a top surface of the second frame. Non-electrode bank regions 9e, 9f, 9g and 9h are formed between respective inner edges of the external connection terminals at the four corners and an inner peripheral edge 221 of the second frame. On the external connection terminal 9c, a protrusion 92c is formed spaced apart from an outer peripheral edge 220 and the inner peripheral edge 221 of the second frame.

Abstract: A piezoelectric device has an insulated container including a frame portion. Four external connection terminals to be solder-bonded to an external substrate each have a shape with a bent portion in plan view in which the external connection terminal is extending from one of the four corners on a bottom surface of the frame portion in a long-side direction and a short-side direction of an outer peripheral edge of the frame portion. The four external connection terminals are spaced from an opening end of a recess with an electrode-absent region interposed therebetween. The four external connection terminals each have a plurality of angular parts in plan view, and at least one of the plurality of angular parts is in proximity to the inner peripheral edge of the frame portion in an arc shape or a chamfered shape at each of the four corners thereof.

Abstract: A piezoelectric resonator device having a sandwich structure is provided, which can be easily adapted to reduction in size. A crystal oscillator 101 includes: a crystal resonator plate 2; a first sealing member 3 covering a first excitation electrode 221 of the crystal resonator plate 2; and a second sealing member 4 covering a second excitation electrode 222 of the crystal resonator plate 2. A substantially rectangular parallelepiped shaped package 12 is formed by bonding: the first sealing member 3 to the crystal resonator plate 2; and the second sealing member 4 to the crystal resonator plate 2. The package 12 includes an internal space 13 in which is hermetically sealed a vibrating part 23 of the crystal resonator plate 2 including the first excitation electrode 221 and the second excitation electrode 222.

Abstract: A piezoelectric resonator device having a sandwich structure is provided, which is stably bonded to an external element. In the piezoelectric resonator device 1, at least a vibrating part 21 of a piezoelectric substrate 2 is sealed by a first sealing member 3 and a second sealing member 4. The piezoelectric substrate 2 includes: the vibrating part 21; and an external frame part 23 that is thicker than the vibrating part 21 and that surrounds the outer periphery of the vibrating part 21. External electrodes 31 to be connected to an external element 5 are provided on at least one of the first sealing member 3 and the second sealing member 4. The external element 5 is connected to the external electrodes 31 at least on the external frame part 23 of the piezoelectric substrate 2.

Abstract: An electronic component-use package includes a base that holds an electronic component element, and terminal electrodes formed on a bottom surface of the base. The terminal electrodes have chamfered parts facing corner parts of the base bottom surface and having angles of chamfer ranging in ±10 degrees to a reference line. The reference line is a perpendicular line to a straight line that connects the corner parts of the base bottom surface to a central part on one side of the terminal electrode in proximity to a center point of the base bottom surface, the reference line L8 passing through the chamfered parts.

Abstract: A piezoelectric device is provided with a rectangular crystal piece having driving electrodes on front and back main faces thereof, and a base member having two electrode pads near one short side of the crystal piece. The crystal piece is supported on the base member by two support portions near one short side thereof, and by an auxiliary support portion on the other short side thereof. A position of the auxiliary support portion relative to the other short side, where L is a distance between two short sides, and H is a distance from the other short side to a peripheral edge of the auxiliary support portion nearest to the other short side, is set to a position at which the distance H stays in a range of distances in which a maximum tensile stress acting on the auxiliary support portion and a maximum von Mises stress of the crystal piece are within predetermined ranges.

Abstract: A piezoelectric resonator device having a sandwich structure is provided, which is capable of improving reliability while ensuring hermeticity of the internal space in which a vibrating part of the piezoelectric resonator plate is sealed. A crystal resonator 101 includes: a crystal resonator plate 2; a first sealing member 3 covering a first excitation electrode 221 of the crystal resonator plate 2; and a second sealing member 4 covering a second excitation electrode 222 of the crystal resonator plate 2. A third through hole 269 is formed in the crystal resonator plate 2 to penetrate between a first main surface 211 and a second main surface 212. A through electrode 71 of the third through hole 269 is conducted to the first excitation electrode 221. A seventh through hole 350 is formed in the first sealing member 3 to penetrate between a first main surface 311 and a second main surface 312.

Abstract: An AT-cut crystal resonator plate (2) includes a first main surface (2a) on which a first excitation electrode (211) is formed and a second main surface (2b) on which a second excitation electrode (212) is formed. The AT-cut crystal resonator plate (2) further includes: a substantially rectangular-shaped vibrating part (21) that is piezoelectrically vibrated when a voltage is applied to the first excitation electrode (211) and the second excitation electrode (212); a holding part (22) protruding from a corner part (21a) of the vibrating part (21) in a Z? axis direction of the AT-cut crystal; and an external frame part (23) configured to surround an external circumference of the vibrating part (21) and to hold the holding part (22).

Abstract: A piezoelectric vibrator according to the invention has a base, an integrated circuit element, and a piezoelectric vibration element. The base has internal terminal pads, and external terminals including an AC output terminal. The base includes rectangular ceramic substrate layers stacked in at least three layers, each of which has castellations formed at four corners. Among the internal terminal pads, internal terminal pads for the integrated circuit element and internal terminal pads for the piezoelectric vibration element are connected to each other by externally exposed wiring patterns formed on upper surfaces of the castellations at the corners of the ceramic substrate constituting a middle layer.