Abstract: A method for forming a microelectromechanical (MEMS) resonator is disclosed. The method comprises first manufacturing a plurality of resonator structures. Each of the resonator structures differ from the others in a systematic manner, such as the length of the resonator structure. The resonance frequency of each of the resonator structures is determined. Then, a desired resonator structure is selected based upon the resonance frequency of the desired resonator structure.

Abstract: A method including to a resonator coupled to at least one support structure on a substrate, the resonator having a resonating frequency in response to a frequency stimulus, modifying the resonating frequency by modifying the at least one support structure. A method including forming a resonator coupled to at least one support structure on a chip-level substrate, the resonator having a resonating frequency; and modifying the resonating frequency of the resonator by modifying the at least one support structure. A method including applying a frequency stimulus to a resonator coupled to at least one support structure on a chip-level substrate determining a resonating frequency; and modifying the resonating frequency of the resonator by modifying the at least one support structure.

Abstract: A mechanical resonator has an electronically adjustable resonance frequency and is especially adapted to be used as a tunable vibration absorber. The mechanical resonator includes an inertial mass mounted on a free end of a spring, which is secured at its other end to the structure that is to be vibrationally damped. In order to vary the resonant frequency of the resonator, an electromechanical converter such as a piezoelectric element is connected to the spring and/or the inertial mass, and a displacement and/or acceleration sensor provides a sensor signal that is dependent on the respective displacement and/or acceleration of the spring and/or the inertial mass. An electronic control circuit generates an actuating signal based on the sensor signal. The actuating signal is applied to the electro-mechanical converter, which responsively exerts an adjusting force onto the spring and/or the inertial mass.

Abstract: Disclosed is a piezoelectric resonator device. This piezoelectric resonator device comprises a piezoelectric substrate having an almost rectangular plane shape. The piezoelectric substrate is provided with a slit extending to the inside from one edge of the piezoelectric substrate, for forming a tuning fork portion, and a pair of slits for separating the tuning fork portion, spaced apart from the slit forming the tuning fork portion by a predetermined distance on both sides of the slit forming the tuning fork portion, and approximately parallel with the slit forming the tuning fork portion. Vibrating electrodes are formed on both major surfaces of the piezoelectric substrate at a piezoelectric vibrating portion, between the slits separating the tuning fork portion from non-vibrating portions of the substrate.

Abstract: A tuning fork type piezoelectric resonator constructed by forming tuning fork arm portions on both sides of a first slit provided for a piezoelectric substrate, forming resonance electrodes on both major surfaces of the piezoelectric substrate in a region around the first slit, and forming steps in outer edges of the tuning fork arm portions.

Abstract: A ladder type filter constructed by laminating serial resonators and parallel resonators, which are respectively constituted by a tuning fork type piezoelectric resonator having a piezoelectric substrate provided with first to third slits extending inward from one edge thereof to form a tuning fork-shaped vibrating portion between the second and third silts, and vibrating electrodes for vibrating the tuning fork-shaped vibrating portion of the piezoelectric substrate. The resonators are laminated with layers having a cavity formed therein interposed in between the resonators. Each layer is constructed so as to ensure that a cavity is provided on both sides of each resonator for allowing the vibration of the tuning fork-shaped vibrating portions. The laminated resonators are integrated to form a ladder type filter which is small in size and can be constructed as an electronic component capable of surface mounting.

Abstract: Disclosed is a piezoelectric resonator device. This piezoelectric resonator device comprises a piezoelectric substrate having an almost rectangular plane shape. The piezoelectric substrate is provided with a slit extending to the inside from one edge of the piezoelectric substrate, for forming a tuning fork portion, and a pair of slits for separating the tuning fork portion, spaced apart from the slit forming the tuning fork portion by a predetermined distance on both sides of the slit forming the tuning fork portion, and approximately parallel with the slit forming the tuning fork portion. Vibrating electrodes are formed on both major surfaces of the piezoelectric substrate at a piezoelectric vibrating portion, between the slits separating the tuning fork portion from non-vibrating portions of the substrate.

Abstract: Disclosed is a piezoelectric resonator device. This piezoelectric resonator device comprises a piezoelectric substrate having an almost rectangular plane shape. The piezoelectric substrate is provided with a slit extending to the inside from one edge of the piezoelectric substrate, for forming a tuning fork portion, and a pair of slits for separating the tuning fork portion, spaced apart from the slit forming the tuning fork portion by a predetermined distance on both sides of the slit forming the tuning fork portion, and approximately parallel with the slit forming the tuning fork portion. Vibrating electrodes are formed on both major surfaces of the piezoelectric substrate at a piezoelectric vibrating portion between the slits separating the tuning fork portion from non-vibrating portions of the substrate.

Abstract: An electrostatic measuring apparatus for measuring unknowns such as the electrostatic potential of a surface in a non-contacting manner, including a tuning fork and a sensing electrode, and in which the frequencies of two different vibration modes of the fork are separated by a slotted supporting structure which is united with the fork, and in which harmful amplitudes of vibration of the fork are avoided by an amplitude limiting structure integral with the sensing electrode. The amplitude limiting structure includes arms extending around the ends of the tines.

Abstract: Disclosed is a piezoelectric resonator device. This piezoelectric resonator device comprises a piezoelectric substrate having an almost rectangular plane shape. The piezoelectric substrate is provided with a slit extending to the inside from one edge of the piezoelectric substrate, for forming a tuning fork portion, a pair of slits for separating the tuning fork portion, spaced apart from the slit forming a tuning fork portion by a predetermined distance on both sides of the slit forming the tuning fork portion, and approximately parallel with the slit forming a tuning fork portion. Vibrating electrodes are formed on both major surfaces of the piezoelectric substrate at a piezoelectric vibrating portion, between the slits separating the tuning fork portion from non-vibrating portions of the substrate.

Abstract: A method of filtering an AC signal using a piezoelectric beam is provided. A piezoelectric film is formed on a mechanical support and a portion of the piezoelectric film forms a beam which extends beyond the mechanical support so that a cavity is formed underneath the beam, and the beam is free to vibrate in the cavity at a resonant frequency when an acoustic wave is propagated in the piezoelectric layer.A depletion region is formed under a Schottky contact which serves as a drive electrode. An unfiltered AC signal is coupled to the drive electrode thereby establishing an acoustic wave when the unfiltered AC signal comprises a component at the resonant frequency. Surface charge on the piezoelectric film resulting from vibration of the beam allows the resonant frequency component of the unfiltered AC signal to pass through the depletion region. Alternatively, the resonant frequency component can be passed by a tunnel current through the cavity.

Abstract: The present invention is directed to a tuning fork wherein a damping piece is provided, either integral with said tuning fork vibrator or a separate piece attached thereto, and wherein a damper member is intersected between said damping piece and a housing for accommodating the tuning fork vibrator.Since the (1/2)f.sub.O spurious response which is caused in the tuning fork vibrator to be spread within the damping piece is adapted to be absorbed by the damper member, the tuning fork is made smaller in shape.

Abstract: A circuit package wherein a framed resonator leaf is mounted in a recessed portion of a plastic body. The contours of the recess orient and support the resonator frame, and an electrically conductive adhesive both bonds the resonator frame to the body and electrically connects the resonator to lead electrodes embedded in the body. A circuit chip element electrically connected to the lead electrodes is also embedded in the body to provide an integral circuit package. A cover over the recess, bonded to the body, protects the resonator element. Welded connections and a resonator mounting plate are not used.

Abstract: A flexural electromechanical transducer composed of a constant-modulus alloy material and a piezoelectric ceramic material having a high electromechanical coupling coefficient. In the transducer, the piezoelectric ceramic material is polarized in one direction and a specified frequency signal is applied to the piezoelectric ceramic material in a direction parallel to the residual polarization direction of the piezoelectric material for obtaining a thickness-shear vibration. The thickness-shear vibration of the piezoelectric material in turn causes the flexural vibration of the transducer. The transducer achieves a high quality factor Q, a low capacitance ratio r, good spurious characteristics, and low impedance.