Abstract: In a method for manufacturing a quartz crystal unit and an electronic apparatus having the quartz crystal unit, each of the quartz crystal unit and the electronic apparatus having the quartz crystal unit, comprising the steps of forming a quartz crystal tuning fork resonator capable of vibrating in a flexural mode of an inverse phase, and having first and second quartz crystal tuning fork tines by etching a quartz crystal wafer; disposing an electrode on each of two of side surfaces of each of the first and second quartz crystal tuning fork tines so that the electrodes on the side surfaces of the first quartz crystal tuning fork tine have an electrical polarity opposite to an electrical polarity of the electrodes on the side surfaces of the second quartz crystal tuning fork tine; mounting the quartz crystal tuning fork resonator on a mounting portion of a case; and connecting a lid to the case to cover an open end thereof, the quartz crystal unit comprising the quartz crystal tuning fork resonator with a piez

Abstract: In a method for manufacturing a quartz crystal unit and an electronic apparatus having the quartz crystal unit, each of the quartz crystal unit and the electronic apparatus having the quartz crystal unit, comprising the steps of forming a quartz crystal tuning fork resonator capable of vibrating in a flexural mode of an inverse phase, and having first and second quartz crystal tuning fork tines by etching a quartz crystal wafer; disposing an electrode on each of two of side surfaces of each of the first and second quartz crystal tuning fork tines so that the electrodes on the side surfaces of the first quartz crystal tuning fork tine have an electrical polarity opposite to an electrical polarity of the electrodes on the side surfaces of the second quartz crystal tuning fork tine; mounting the quartz crystal tuning fork resonator on a mounting portion of a case; and connecting a lid to the case to cover an open end thereof, the quartz crystal unit comprising the quartz crystal tuning fork resonator with a piez

Abstract: A method for manufacturing an electronic apparatus comprises forming a quartz crystal tuning fork resonator having a fundamental mode of vibration and a second overtone mode of vibration each comprised of a flexural mode of an inverse phase, a series resistance R1 of the fundamental mode of vibration and a series resistance R2 of the second overtone mode of vibration. An amplification circuit is provided having a CMOS inverter, a feedback resistor, a negative resistance ?RL1 for the fundamental mode of vibration of the quartz crystal tuning fork resonator, and a negative resistance ?RL2 for the second overtone mode of vibration thereof. A feedback circuit is provided having the quartz crystal tuning fork resonator, a plurality of capacitors and a drain resistor. The quartz crystal tuning fork resonator is electrically connected to the CMOS inverter and the feedback resistor of the amplification circuit and to the capacitors and the drain resistor of the feedback circuit.

Abstract: In a method for manufacturing a quartz crystal unit, a quartz crystal tuning fork resonator is formed by etching a quartz crystal wafer to form a quartz crystal tuning fork base and first and second quartz crystal tuning fork tines connected to the quartz crystal tuning fork base. The quartz crystal tuning fork resonator has a piezoelectric constant e?12 within a range of 0.12 C/m2 to 0.19 C/m2 in the absolute value to drive the quartz crystal tuning fork resonator. An electrode is disposed on each of two of side surfaces of each of the first and second quartz crystal tuning fork tines so that the electrodes disposed on the side surfaces of the first quartz crystal tuning fork tine have an electrical polarity opposite to an electrical polarity of the electrodes disposed on the side surfaces of the second quartz crystal tuning fork tine. The quartz crystal tuning fork resonator is mounted on a mounting portion of a case.

Abstract: A quartz crystal unit comprising a quartz crystal tuning fork resonator capable of vibrating in a flexural mode of an inverse phase and having a quartz crystal tuning fork base, and first and second quartz crystal tuning fork tines connected to the quartz crystal tuning fork base, an electrode being disposed on each of two of side surfaces of each of the first and second quartz crystal tuning fork tines so that the electrode disposed on each of two of the side surfaces of the first quartz crystal tuning fork tine has an electrical polarity opposite to an electrical polarity of the electrode disposed on each of two of the side surfaces of the second quartz crystal tuning fork tine, a motional capacitance C1 of a fundamental mode of vibration of the quartz crystal tuning fork resonator being greater than a motional capacitance C2 of a second overtone mode of vibration thereof.

Abstract: A piezoelectric crystal tuning fork resonator comprises a tuning fork base and a plurality of tuning fork tines connected to the tuning fork base, each of the tuning fork tines having opposite main surfaces and side surfaces, a groove having a plurality of stepped portions being formed in at least one of the opposite main surfaces of each of the tuning fork tines, a plurality of first electrodes being disposed on the stepped portions of the groove in at least one of the opposite main surfaces of each of the tuning fork tines, a plurality of second electrodes being disposed on the side surfaces of each of the tuning fork tines, the piezoelectric crystal tuning fork resonator comprising three electrode terminals and each of the three electrode terminals having a different electrical polarity.

Abstract: A resonator comprises a base portion and a plurality of vibrational arms connected to the base portion and vibratable in a flexural mode. An electrode is disposed on at least one of opposite side surfaces of each of the vibrational arms so that a capacitance ratio r1 of a fundamental mode of vibration of the resonator is less than a capacitance ratio r2 of a second overtone mode of vibration thereof. A groove is formed in at least one of opposite main surfaces of each of the vibrational arms, and at least one mounting arm protrudes from the base portion.

Abstract: An electronic apparatus comprises at least one quartz crystal oscillator comprised of a quartz crystal oscillating circuit having a quartz crystal resonator, an amplifier, at least one resistor, and capacitors. The quartz crystal resonator comprises a quartz crystal tuning fork resonator having a quartz crystal tuning fork base, quartz crystal tuning fork tines connected to the quartz crystal tuning fork base, and at least one groove formed in at least one of opposite main surfaces of the quartz crystal tuning fork tines. A length of the at least one groove formed in at least one of the opposite main surfaces of the quartz crystal tuning fork tines is within a range of 40% to 80% of a length of the quartz crystal tuning fork tines.

Abstract: A resonator comprises a base portion and a plurality of vibrational arms connected to the base portion and vibratable in a flexural mode. An electrode is disposed on at least one of opposite side surfaces of each of the vibrational arms so that a capacitance ratio r1 of a fundamental mode of vibration of the resonator is less than a capacitance ratio r2 of a second overtone mode of vibration thereof. A groove is formed in at least one of opposite main surfaces of each of the vibrational arms, and at least one mounting arm protrudes from the base portion.

Abstract: An electronic apparatus comprises a display portion and a plurality of oscillators, one of which is a quartz crystal oscillator comprising: a quartz crystal oscillating circuit comprising; an amplification circuit and a feedback circuit. For example, the feedback circuit is constructed by a quartz crystal resonator comprising vibrational arms and a base portion, and having novel shape and electrode construction. Also, the quartz crystal resonator is housed in a package. In addition, from a relationship of an amplification rate of the amplification circuit and a feedback rate of the feedback circuit, an output signal of the quartz crystal oscillating circuit having an oscillation frequency of a fundamental mode of vibration for the quartz crystal resonator can be provided with a frequency of high stability.

Abstract: The electronic apparatus comprises a display portion and a quartz crystal oscillator at least, and said electronic apparatus comprises at least two quartz crystal oscillators. Also, each of two quartz crystal oscillators of the at least two oscillators comprises a quartz crystal oscillating circuit having an amplification circuit and a feedback circuit. The feedback circuit is constructed by a flexural mode, quartz crystal tuning fork resonator or a width-extensional mode quartz crystal resonator or a thickness shear mode quartz crystal resonator and for example, the quartz crystal tuning fork resonator comprising tuning fork tines and tuning fork base that are formed integrally, is shown with novel shape and electrode construction. Also, the quartz crystal tuning fork resonator, capable of vibrating in a fundamental mode and having a high frequency stability can be provided with a small series resistance and a high quality factor, even when the tuning fork resonator is miniaturized.

Abstract: In an electronic apparatus comprising a digital display portion and first and second oscillators comprising first and second oscillating circuits, each of the first and second oscillating circuits having a resonator, an amplifier, a plurality of capacitors, and at least one resistor, a mode of vibration of the resonator of the first oscillating circuit being the same as that of the resonator of the second oscillating circuit, an output signal being output from each of the first and second oscillating circuits, the output signal of one of the first and second oscillating circuits being a clock signal for use in operation of the electronic apparatus to display time information at the digital display portion.

Abstract: The electronic apparatus comprises a display portion and a quartz crystal oscillator at least, and said electronic apparatus comprises at least one quartz crystal oscillator. Also, the at least one oscillator comprises a quartz crystal oscillating circuit comprising an amplification circuit and a feedback circuit. The feedback circuit is constructed by a flexural mode, quartz crystal tuning fork resonator or a length-extensional mode quartz crystal resonator and for example, the quartz crystal tuning fork resonator comprising tuning fork tines and tuning fork base that are formed integrally, is shown with novel shape and electrode construction. Also, the quartz crystal tuning fork resonator, capable of vibrating in a fundamental mode and having a high frequency stability can be provided with a small series resistance and a high quality factor, even when the tuning fork resonator is miniaturized.

Abstract: A quartz crystal resonator has a quartz crystal tuning fork base and quartz crystal tuning fork tines connected to the quartz crystal tuning fork base. Each of the quartz crystal tuning fork tines has opposite main surfaces, a groove formed in at least one of the main surfaces, and an electrode disposed in the groove formed in at least one of the main surfaces so that a merit value M1 of a fundamental mode of vibration of the quartz crystal tuning fork resonator is greater than a merit value M2 of a second overtone mode of vibration thereof. The merit values M1 and M2 are defined by the ratios Q1/r1 and Q2/r2, respectively, where Q1 and Q2 represent a quality factor of the fundamental mode of vibration and the second overtone mode of vibration, respectively, of the quartz crystal tuning fork resonator and r1 and r2 represent a capacitance ratio of the fundamental mode of vibration and the second overtone mode of vibration, respectively, of the quartz crystal tuning fork resonator.

Abstract: In a method for manufacturing a quartz crystal unit and an electronic apparatus having the quartz crystal unit, each of the quartz crystal unit and the electronic apparatus having the quartz crystal unit, comprising the steps of forming a quartz crystal tuning fork resonator capable of vibrating in a flexural mode of an inverse phase, and having first and second quartz crystal tuning fork tines by etching a quartz crystal wafer; disposing an electrode on each of two of side surfaces of each of the first and second quartz crystal tuning fork tines so that the electrodes on the side surfaces of the first quartz crystal tuning fork tine have an electrical polarity opposite to an electrical polarity of the electrodes on the side surfaces of the second quartz crystal tuning fork tine; mounting the quartz crystal tuning fork resonator on a mounting portion of a case; and connecting a lid to the case to cover an open end thereof, the quartz crystal unit comprising the quartz crystal tuning fork resonator with a piez

Abstract: A method for manufacturing an electronic apparatus comprises forming a quartz crystal tuning fork resonator having a fundamental mode of vibration and a second overtone mode of vibration each comprised of a flexural mode of an inverse phase, a series resistance R1 of the fundamental mode of vibration and a series resistance R2 of the second overtone mode of vibration. An amplification circuit is provided having a CMOS inverter, a feedback resistor, a negative resistance ?RL1 for the fundamental mode of vibration of the quartz crystal tuning fork resonator, and a negative resistance ?RL2 for the second overtone mode of vibration thereof. A feedback circuit is provided having the quartz crystal tuning fork resonator, a plurality of capacitors and a drain resistor. The quartz crystal tuning fork resonator is electrically connected to the CMOS inverter and the feedback resistor of the amplification circuit and to the capacitors and the drain resistor of the feedback circuit.

Abstract: A quartz crystal tuning fork resonator is manufactured with a fundamental mode of vibration and a second overtone mode of vibration each comprised of a flexural mode of an inverse phase. A merit value M1 of the fundamental mode of vibration is greater than a merit value M2 of the second overtone mode of vibration thereof so that the second overtone mode of vibration is suppressed and a high frequency stability is obtained for the fundamental mode of vibration. The merit values M1 and M2 are defined by the ratios Q1/r1 and Q2/r2, respectively, where Q1 and Q2 represent a quality factor of the fundamental mode of vibration and the second overtone mode of vibration, respectively, and r1 and r2 represent a capacitance ratio of the fundamental mode of vibration and the second overtone mode of vibration, respectively, of the quartz crystal tuning fork resonator.

Abstract: In a method for manufacturing a quartz crystal oscillator, at least one of a chemical etching method, a physical etching method, and a mechanical method is utilized to form a quartz crystal tuning fork resonator having a quartz crystal tuning fork base, quartz crystal tuning fork tines connected to the quartz crystal tuning fork base, a fundamental mode of vibration, and a second overtone mode of vibration each comprised of a flexural mode of an inverse phase. An amplification circuit is provided having at least an amplifier. A feedback circuit is provided having the quartz crystal tuning fork resonator and capacitors. The amplifier of the amplification circuit and the quartz crystal tuning fork resonator and capacitors of the feedback circuit are electrically connected together.

Abstract: The electronic apparatus comprises a display portion and a quartz crystal oscillator at least, and said electronic apparatus comprises at least two quartz crystal oscillators. Also, each of two quartz crystal oscillators of the at least two oscillators comprises a quartz crystal oscillating circuit having an amplification circuit and a feedback circuit. The feedback circuit is constructed by a flexural mode, quartz crystal tuning fork resonator or a width-extensional mode quartz crystal resonator or a thickness shear mode quartz crystal resonator and for example, the quartz crystal tuning fork resonator comprising tuning fork tines and tuning fork base that are formed integrally, is shown with novel shape and electrode construction. Also, the quartz crystal tuning fork resonator, capable of vibrating in a fundamental mode and having a high frequency stability can be provided with a small series resistance and a high quality factor, even when the tuning fork resonator is miniaturized.

Abstract: In method for manufacturing a quartz crystal tuning fork resonator capable of vibrating in a flexural mode, a quartz crystal wafer is etched in a first etching process to form a quartz crystal tuning fork base and quartz crystal tuning fork tines connected to the quartz crystal tuning fork base. The quartz crystal wafer is etched in a second etching process different from the first etching process to form a groove having stepped portions in at least one of opposite main surfaces of each of the quartz crystal tuning fork tines. First electrodes having a first electrical polarity are disposed on the stepped portions of the grooves of respective ones of the quartz crystal tuning fork tines. Second electrodes having a second electrical polarity opposite to the first electrical polarity are disposed on side surfaces of respective ones of the quartz crystal tuning fork tines.