Abstract: A vibration device includes a cylindrical body including an opening, a light-transmissive cover joined to the cylindrical body, a piezoelectric element directly or indirectly joined to the cylindrical body and including first and second main surfaces, and a power feeder joined to the piezoelectric element. The power feeder includes a substrate including first and second surfaces, first and second power feeding electrodes on the first surface or the second surface, and first and second external connection electrodes. The power feeder sandwiches the piezoelectric element in a thickness direction, and the first and second power feeding electrodes are joined to the first main surface or the second main surface of the piezoelectric element. Portions of the substrate, which are not located on the first and second main surfaces of the piezoelectric element, are bent to sandwich the piezoelectric element.

Abstract: A vibration device includes a cylindrical body including a cavity, a first opening end surface, and a second opening end surface, a light-transmissive cover directly or indirectly bonded to the first opening end surface of the cylindrical body so as to cover the cavity of the cylindrical body, a piezoelectric body directly or indirectly bonded to the cylindrical body, and a buffer layer provided between at least one of the cylindrical body and the piezoelectric body, and the cylindrical body and the light-transmissive cover. The buffer layer includes an inner end portion on an inner side portion in a direction orthogonal or substantially orthogonal to the axial direction and an outer end portion on an outer side portion in a direction orthogonal or substantially orthogonal to the axial direction. A thickness of the inner end portion is larger than a thickness of the outer end portion.

Abstract: A vibration device includes a tubular vibration body, a retainer fixed to the vibration body, and a light transmissive body to be vibrated by the vibration body and held between the vibration body and the retainer. The light transmissive body includes a first surface and a second surface opposed to the first surface. The vibration body includes one end supporting the first surface of the light transmissive body. The retainer includes a side wall including a first end and a second end surrounding an outer circumference of the light transmissive body, and a supporting portion extending inwardly with respect to the side wall from the first end of the side wall. The retainer is fixed to the vibration body at a portion in contact with the vibration body on a side of the second end. The supporting portion includes a supporting surface on a side of the second surface of the light transmissive body to support the second surface of the light transmissive body.

Abstract: A vibration device includes a light-transmissive body, and a vibrator to vibrate the light-transmissive body at a vibration acceleration of equal to or more than about 1.5×105 m/s2 and equal to or less than about 8.0×105 m/s2.

Abstract: A vibration device includes a vibrator including a cylinder including an opening, a light-transmissive cover directly or indirectly coupled to the cylinder to cover the opening of the cylinder, and a piezoelectric element to vibrate the light-transmissive cover, and including an opening end portion, an elastic member holding the opening end portion of the vibrator, and a case connected to the elastic member.

Abstract: A vibration device includes a cylindrical body including an opening, a light-transmissive cover joined to the cylindrical body, a piezoelectric element directly or indirectly joined to the cylindrical body and including first and second main surfaces, and a power feeder joined to the piezoelectric element. The power feeder includes a substrate including first and second surfaces, first and second power feeding electrodes on the first surface or the second surface, and first and second external connection electrodes. The power feeder sandwiches the piezoelectric element in a thickness direction, and the first and second power feeding electrodes are joined to the first main surface or the second main surface of the piezoelectric element. Portions of the substrate, which are not located on the first and second main surfaces of the piezoelectric element, are bent to sandwich the piezoelectric element.

Abstract: A vibration device includes a cylindrical body including a cavity, a first opening end surface, and a second opening end surface, a light-transmissive cover directly or indirectly bonded to the first opening end surface of the cylindrical body so as to cover the cavity of the cylindrical body, a piezoelectric body directly or indirectly bonded to the cylindrical body, and a buffer layer provided between at least one of the cylindrical body and the piezoelectric body, and the cylindrical body and the light-transmissive cover. The buffer layer includes an inner end portion on an inner side portion in a direction orthogonal or substantially orthogonal to the axial direction and an outer end portion on an outer side portion in a direction orthogonal or substantially orthogonal to the axial direction. A thickness of the inner end portion is larger than a thickness of the outer end portion.

Abstract: A vibration device includes a light-transmissive cover, a piezoelectric element to vibrate the light-transmissive cover, at least one vibration body connected to the piezoelectric element, at least one power feed conductor in contact with the piezoelectric element and feeding power to the piezoelectric element, and at least one elastic portion to press the at least one power feed conductor against the piezoelectric element.

Abstract: A magnetic sensor senses a magnetic field in a predetermined magnetic sensing direction. The magnetic sensor includes a chip on which at least one magnetic device is provided. The length of the chip in the magnetic sensing direction is twice or more the length of the chip in an orthogonal direction that is orthogonal or substantially orthogonal to the magnetic sensing direction.

Abstract: A vibration device includes a vibrator including a cylinder including an opening, a light-transmissive cover directly or indirectly coupled to the cylinder to cover the opening of the cylinder, and a piezoelectric element to vibrate the light-transmissive cover, and including an opening end portion, an elastic member holding the opening end portion of the vibrator, and a case connected to the elastic member.

Abstract: A magnetic sensor senses a magnetic field in a predetermined magnetic sensing direction. The magnetic sensor includes a chip on which at least one magnetic device is provided. The length of the chip in the magnetic sensing direction is twice or more the length of the chip in an orthogonal direction that is orthogonal or substantially orthogonal to the magnetic sensing direction.

Abstract: A nonreciprocal circuit device has a structure that allows a direct current magnetic field having an even density to be applied to a necessary portion of a ferrite without impairing a reduction in profile so as to improve insertion loss. The nonreciprocal circuit device, for example, a two-port isolator, includes permanent magnets, a ferrite to which a direct current magnetic field is applied by the permanent magnets, and a first center electrode and a second center electrode that are disposed on the ferrite. The permanent magnets are disposed so as to oppose principal surfaces of the ferrite. Portions of each of the permanent magnets opposing relay electrodes on top and bottom surfaces are preferably thicker than other portions thereof.

Abstract: A non-reciprocal circuit device capable of preventing and minimizing disturbances in magnetic field distribution in a ferrite to thereby improve insertion loss characteristics and isolation characteristics includes a ferrite to which a DC magnetic field is applied by permanent magnets and first and second center electrodes disposed on the ferrite. A conductive material is embedded in a recess provided in an end surface of the ferrite that is perpendicular or substantially perpendicular to the first and second principal surfaces of the ferrite, and the first and second center electrodes are electrically connected to the conductive material to define a circuit. Opening portions of the recess facing the first and second principal surfaces are arranged such that the opening portion at a downstream side of a direction of application of the DC magnetic field by the permanent magnets is larger than the opening portion at an upstream side thereof.

Abstract: A nonreciprocal circuit device has a structure that allows a direct current magnetic field having an even density to be applied to a necessary portion of a ferrite without impairing a reduction in profile so as to improve insertion loss. The nonreciprocal circuit device, for example, a two-port isolator, includes permanent magnets, a ferrite to which a direct current magnetic field is applied by the permanent magnets, and a first center electrode and a second center electrode that are disposed on the ferrite. The permanent magnets are disposed so as to oppose principal surfaces of the ferrite. Portions of each of the permanent magnets opposing relay electrodes on top and bottom surfaces are preferably thicker than other portions thereof.

Abstract: A non-reciprocal circuit device capable of preventing and minimizing disturbances in magnetic field distribution in a ferrite to thereby improve insertion loss characteristics and isolation characteristics includes a ferrite to which a DC magnetic field is applied by permanent magnets and first and second center electrodes disposed on the ferrite. A conductive material is embedded in a recess provided in an end surface of the ferrite that is perpendicular or substantially perpendicular to the first and second principal surfaces of the ferrite, and the first and second center electrodes are electrically connected to the conductive material to define a circuit. Opening portions of the recess facing the first and second principal surfaces are arranged such that the opening portion at a downstream side of a direction of application of the DC magnetic field by the permanent magnets is larger than the opening portion at an upstream side thereof.

Abstract: An antenna device having a feeder electrode that extends linearly on a top surface of a dielectric substrate. A balanced electrode having two balanced transmission electrodes vertical to the extending direction of the feeder electrode and extending in parallel. The two balanced transmission electrodes are connected to the feeder electrode and separated by an interval of ½ of a wavelength of a transmission/reception signal. A radiation electrode having a first electrode connected to the one of the two balanced transmission electrodes and a second electrode connected to the other of the two balanced transmission electrodes and is positioned parallel to the feeder electrode. A waveguide electrode is formed at a position separated from the radiation electrode by a predetermined interval and in parallel to the radiation electrode. A ground electrode is formed at an area of a back surface of the dielectric substrate corresponding to an area including a portion where the feeder electrode is positioned.

Abstract: An antenna device having a feeder electrode that extends linearly on a top surface of a dielectric substrate. A balanced electrode having two balanced transmission electrodes vertical to the extending direction of the feeder electrode and extending in parallel. The two balanced transmission electrodes are connected to the feeder electrode and separated by an interval of ½ of a wavelength of a transmission/reception signal. A radiation electrode having a first electrode connected to the one of the two balanced transmission electrodes and a second electrode connected to the other of the two balanced transmission electrodes and is positioned parallel to the feeder electrode. A waveguide electrode is formed at a position separated from the radiation electrode by a predetermined interval and in parallel to the radiation electrode. A ground electrode is formed at an area of a back surface of the dielectric substrate corresponding to an area including a portion where the feeder electrode is positioned.

Abstract: An antenna apparatus includes two circular waveguides including a fixed-side circular waveguide and a rotation-side circular waveguide, each having a propagation mode in a TM01 mode, and being arranged coaxially with each other while a waveguide-side choke is provided between the two waveguides. A rectangular waveguide is connected to the fixed-side circular waveguide. Thereby, the high-frequency signal fed from the rectangular waveguide to the fixed-side circular waveguide can be radiated from a primary radiator to which the rotation-side circular waveguide is connected. While the circular waveguides and the waveguide-side choke can constitute a rotary joint, by rotating the primary radiator together with the rotation-side circular waveguide, scanning can be carried out with a high-frequency signal radiated from the primary radiator.

Abstract: An antenna apparatus includes two circular waveguides including a fixed-side circular waveguide and a rotation-side circular waveguide, each having a propagation mode in a TM01 mode, and being arranged coaxially with each other while a waveguide-side choke is provided between the two waveguides. A rectangular waveguide is connected to the fixed-side circular waveguide. Thereby, the high-frequency signal fed from the rectangular waveguide to the fixed-side circular waveguide can be radiated from a primary radiator to which the rotation-side circular waveguide is connected. While the circular waveguides and the waveguide-side choke can constitute a rotary joint, by rotating the primary radiator together with the rotation-side circular waveguide, scanning can be carried out with a high-frequency signal radiated from the primary radiator.

Abstract: A sector antenna apparatus mounted on a vehicle has a casing, in which six horn antennas having apertures over an angular range of 180 degrees and extending radially are accommodated. The proximal ends of the horn antennas are connected to an antenna changeover switch. A portion of the horn antennas which emits beam radiation in the forward and backward direction and diagonal direction of the vehicle have large apertures, and a portion of the horn antennas which emits beam radiation to the right and left of the vehicle have a small aperture. Thus, the required antenna characteristics, such as angular resolution, beam width, antenna gain, are achievable in the required direction.