Abstract: The dielectric notch filter of the invention includes: a transmission line for transmitting a high-frequency signal; input and output terminals provided at both ends of the transmission line; a ground conductor for supplying a ground potential; and a dielectric resonator connected to the ground conductor and the transmission line. The dielectric notch filter further includes an impedance matching element connected to the ground conductor and the transmission line in parallel with the dielectric resonator. The dielectric resonator includes: a cavity connected to the ground conductor; a dielectric block provided in the cavity; a coupling device coupled with an electromagnetic field, produced in the cavity; and a coupling adjusting line for connecting the coupling device to the transmission line and for adjusting the degree of electromagnetic coupling.

Abstract: The dielectric notch filter of the invention includes: a transmission line for transmitting a high-frequency signal; input and output terminals provided at both ends of the transmission line; a ground conductor for supplying a ground potential; and a dielectric resonator connected to the ground conductor and the transmission line. The dielectric notch filter further includes an impedance matching element connected to the ground conductor and the transmission line in parallel with the dielectric resonator. The dielectric resonator includes: a cavity connected to the ground conductor; a dielectric block provided in the cavity; a coupling device coupled with an electromagnetic field produced in the cavity; and a coupling adjusting line for connecting the coupling device to the transmission line and for adjusting the degree of electromagnetic coupling.

Abstract: A dielectric antenna duplexer used in a high frequency radio device such as a portable telephone, and a dielectric filter for forming the duplexer of the SIR (stepped impedance resonator) composed by cascade connection of first transmission lines having one end grounded and second transmission lines having one end open and lower in characteristic impedance than in the first transmission lines, first transmission lines and second transmission lines are individually coupled in electromagnetic field, thereby forming an antenna duplexer and a dielectric filter of small insertion loss, high bandwidth selectivity, excellent band pass characteristic, and low cost.

Abstract: An oscillator in which organic substances derived from an active element fixing adhesive do not deposit on an oscillating element and in which when the active element or the oscillating element is damaged, other good parts that are not defective can be reused. In the oscillator, an active element 2 is mounted inside a first container 1 whose upper surface is opened, and not only the opening of the first container 1 is closed by an oscillating unit 3 having an oscillating element 6 incorporated therein, but also the oscillating unit 3 is attached onto the opening of the first container 1, so that second connecting electrodes 11a to 11d of a second container 5 of the oscillating unit 3 are electrically connected to first connecting electrodes 14a to 14d of the first container 1.

Abstract: A piezoelectric device includes a piezoelectric plate provided with at least one electrode at almost a central portion of each face; a first plate made of an ionic material having a recessed portion to cover the at least one electrode at one face to face the piezoelectric plate; and a second plate made of an ionic material having a recessed portion to cover the at least one electrode at one face to face the piezoelectric plate. Each of the at least one electrode is packaged by direct bonding the piezoelectric plate with the first plate and the second plate so as to be sandwiched therebetween. A package includes a body member made of an ionic material provided with a recessed portion or an opening, having a flat face around the recessed portion or the opening; and a covering member made of an ionic material having a flat face to cover the body member.

Abstract: A dielectric antenna duplexer used in a high frequency radio device such as a portable telephone, and a dielectric filter for forming the duplexer of the SIR (stepped impedance resonator) composed by cascade connection of first transmission lines having one end grounded and second transmission lines having one end open and lower in characteristic impedance than in the first transmission lines, first transmission lines and second transmission lines are individually coupled in electromagnetic field, thereby forming an antenna duplexer and a dielectric filter of small insertion loss, high bandwidth selectivity, excellent band pass characteristic, and low cost.

Abstract: The dielectric notch filter of the invention includes: a transmission line for transmitting a high-frequency signal; input and output terminals provided at both ends of the transmission line; a ground conductor for supplying a ground potential; and a dielectric resonator connected to the ground conductor and the transmission line. The dielectric notch filter further includes an impedance matching element connected to the ground conductor and the transmission line in parallel with the dielectric resonator. The dielectric resonator includes: a cavity connected to the ground conductor; a dielectric block provided in the cavity; a coupling device coupled with an electromagnetic field produced in the cavity; and a coupling adjusting line for connecting the coupling device to the transmission line and for adjusting the degree of electromagnetic coupling.

Abstract: A semiconductor device comprising a main circuit having a p-channel MOSFET formed on the surface off the substrate and an n-channel MOSFET formed on the p-type well region which is formed on the n-type Si substrate chip), an input/output (I/O) circuit formed on the substrate, and a substrate bias generating circuit formed on the substrate, characterized by controlling the substrate bias generating circuit via the I/O circuit, and varying a bias supplied to the substrate and the p-type well region, in accordance with the operation mode of the main circuit.

Abstract: A piezoelectric device includes a piezoelectric plate provided with at least one electrode at almost a central portion of each face; a first plate made of an ionic material having a recessed portion to cover the at least one electrode at one face to face the piezoelectric plate; and a second plate made of an ionic material having a recessed portion to cover the at least one electrode at one face to face the piezoelectric plate. Each of the at least one electrode is packaged by direct bonding the piezoelectric plate with the first plate and the second plate so as to be sandwiched therebetween. A package includes a body member made of an ionic material provided with a recessed portion or an opening, having a flat face around the recessed portion or the opening; and a covering member made of an ionic material having a flat face to cover the body member.

Abstract: A temperature compensated crystal oscillator including: an oscillation circuit having a quartz crystal resonator and a control terminal, for providing an oscillating signal determined by the quartz crystal resonator and a control signal, the control signal being applied to the control terminal; a temperature detecting circuit for detecting an operation temperature and outputting a temperature signal based on the operation temperature; and a control signal generating circuit for receiving the temperature signal from the temperature detecting circuit, generating the control signal based on a characteristic curve, and outputting the control signal to the control terminal; the characteristic curve essentially consisting of a plurality of straight lines and being an approximation of an ideal control curve in a predetermined operation temperature range including the operation temperature, the ideal control curve having a relationship between the control signal and the temperature signal for ideally compensating a f

Abstract: A method of directly bonding a crystal to a crystal includes the steps of mirror-polishing the surfaces of the crystals and then rinsing them with a cleaning material and then affecting a baking operation and then bonding them together and thereafter annealing them within a temperature range where crystal crystallization is not transited in phase so that a further strong bonding force is obtained. A crystal resonator is obtained where electrodes are oppositely established across a ply crystal blank with at least two sheets of crystal blanks having a desired cut angle and a desired thickness being directly bonded so that the respective crystal axes intersect at the desired angles. The ply crystal blank may have a central portion which is either thicker or thinner than a surrounding portion.