Abstract: An acoustic wave device includes an input terminal; a balun that is connected to the input terminal, converts a signal input from the input terminal into two anti-phase signals, and outputs the two anti-phase signals; and a filter that is connected to the balun, and outputs the two anti-phase signals input from the balun as balanced output signals. An output impedance of the balun is equal to an input impedance of the filter, and is larger than an output impedance of the filter.

Abstract: A surface acoustic wave device includes a supporting substrate, a LiTaO3 piezoelectric substrate joined on the supporting substrate, which has a normal line direction on a main surface thereof in a direction rotated 43° to 53° from a Y axis to a Z axis direction about an X axis, and an electrode pattern formed on the piezoelectric substrate.

Abstract: A surface acoustic wave device having a surface acoustic wave filter having a comb-shaped electrode pattern formed on a piezoelectric element, electrode terminals for inputting and outputting of the surface acoustic wave filter are connected with corresponding electrode patterns of a package through bumps, wherein the comb-shaped electrode pattern has a pair of reflective electrodes, and an input comb-shaped electrode and an output comb-shaped electrode disposed between the pair of reflective electrodes; and an electrode terminal of either the input comb-shaped electrode or an output comb-shaped electrode is disposed such that the electrode terminal is positioned on the side opposite to the side of the other electrode terminal sandwiching a grounded electrode using a routing pattern.

Abstract: A surface acoustic wave device includes a supporting substrate, a LiTaO3 piezoelectric substrate joined on the supporting substrate, which has a normal line direction on a main surface thereof in a direction rotated 43° to 53° from a Y axis to a Z axis direction about an X axis, and an electrode pattern formed on the piezoelectric substrate.

Abstract: A balance filter includes a first filter having first multimode surface acoustic wave (SAW) filters connected in parallel, a second filter that is connected to the first filter and includes a second multimode SAW filter, a first terminal connected to the first filter, and second terminals connected to the second filters. An input terminal of the balance filter is one of the first and second terminals, and an output terminal thereof is the other. Electric signals transmitted from the first to second filters or vice versa are in opposite phase. Electric signals are input or output via the second terminals in opposite phase.

Abstract: A multimode type SAW filter includes a piezoelectric substrate, and IDT groups formed on the piezoelectric substrate, the IDT groups each having multiple IDTs connected in series in which an input/output electrode and a ground electrode are coupled via a floating conductor. Adjacent electrode fingers between adjacent IDTs among the multiple IDTs of the IDT groups include a first electrode finger connected to the floating conductor in one of the IDT groups and a second electrode finger connected to one of the input/output electrode and the ground electrode in another one of the IDT groups.

Abstract: A surface acoustic wave device having a given impedance includes multimode type filters connected in series. A composite impedance of the multimode type filters defines the given impedance of the surface acoustic wave device.

Abstract: A surface acoustic wave device having a surface acoustic wave filter having a comb-shaped electrode pattern formed on a piezoelectric element, electrode terminals for inputting and outputting of the surface acoustic wave filter are connected with corresponding electrode patterns of a package through bumps, wherein the comb-shaped electrode pattern has a pair of reflective electrodes, and an input comb-shaped electrode and an output comb-shaped electrode disposed between the pair of reflective electrodes; and an electrode terminal of either the input comb-shaped electrode or an output comb-shaped electrode is disposed such that the electrode terminal is positioned on the side opposite to the side of the other electrode terminal sandwiching a grounded electrode using a routing pattern.

Abstract: A multimode type SAW filter includes a piezoelectric substrate, and IDT groups formed on the piezoelectric substrate, the IDT groups each having multiple IDTs connected in series in which an input/output electrode and a ground electrode are coupled via a floating conductor. Adjacent electrode fingers between adjacent IDTs among the multiple IDTs of the IDT groups include a first electrode finger connected to the floating conductor in one of the IDT groups and a second electrode finger connected to one of the input/output electrode and the ground electrode in another one of the IDT groups.

Abstract: A surface acoustic wave device having a given impedance includes multimode type filters connected in series. A composite impedance of the multimode type filters defines the given impedance of the surface acoustic wave device.

Abstract: A surface acoustic wave device that has surface acoustic wave resonators connected in a multi-stage ladder arrangement, includes: two or more different pitches of comb-like drive electrodes of parallel-arm resonators (P1˜P3) and two or more different pitches of comb-like drive electrodes of series-arm resonators (S1˜S3); reflection electrodes (12, 14) placed at either side of a comb-like drive electrode having a pitch different from that of said comb-like drive electrode; and two or more different electrostatic capacitances of parallel-arm resonators and two or more different electrostatic capacitances of series-arm resonators.

Abstract: A surface acoustic wave device that has surface acoustic wave resonators connected in a multi-stage ladder arrangement, includes: two or more different pitches of comb-like drive electrodes of parallel-arm resonators (P1˜P3) and two or more different pitches of comb-like drive electrodes of series-arm resonators (S1˜S3); reflection electrodes (12, 14) placed at either side of a comb-like drive electrode having a pitch different from that of said comb-like drive electrode; and two or more different electrostatic capacitances of parallel-arm resonators and two or more different electrostatic capacitances of series-arm resonators.

Abstract: A surface acoustic wave device includes a package having a coefficient of linear expansion; and a piezoelectric element forming a surface acoustic wave element, and mounted on the package by a flip chip bonding. The piezoelectric element has different coefficients of linear expansion in a direction of propagation of surface acoustic waves generated by an interdigital electrode of the surface acoustic wave element and in a vertical direction thereto, and further has a long side existing to a direction having a coefficient of linear expansion close to the coefficient of linear expansion of the package. The piezoelectric element is cut out from a single crystal having X, Y, and Z crystal axes, and the X crystal axis agrees with a direction of propagation of the surface acoustic wave.

Abstract: A surface acoustic wave device includes a package having a coefficient of linear expansion; and a piezoelectric element forming a surface acoustic wave element, and mounted on the package by a flip chip bonding. The piezoelectric element has different coefficients of linear expansion in a direction of propagation of surface acoustic waves generated by an interdigital electrode of the surface acoustic wave element and in a vertical direction thereto, and further has a long side existing to a direction having a coefficient of linear expansion close to the coefficient of linear expansion of the package. The piezoelectric element is cut out from a single crystal having X, Y, and Z crystal axes, and the X crystal axis agrees with a direction of propagation of the surface acoustic wave.

Abstract: There are disclosed herein novel derivatives of 26,26,26,27,27,27-hexafluorovitamin D.sub.3 providing excellent pharmacological effects, and a process for the preparation thereof. These novel compounds are represented by the general formula ##STR1## wherein R.sub.1 and R.sub.2 each denotes a hydrogen atom or a protecting group for the hydroxyl group; R.sub.3 and R.sub.4 each denotes a hydrogen atom, a hydroxyl group or a protected hydroxyl group and R.sub.4 ' and R.sub.5 ' each denotes a hydrogen atom, or alternatively R.sub.3 and R.sub.3 ' together or R.sub.4 and R.sub.4 ' together denote an oxo group; provided that R.sub.3, R.sub.3 ', R.sub.4 and R.sub.4 ' cannot denote hydrogen atoms simultaneously. The process for the preparation comprises subjecting a previtamin D.sub.3 derivative represented by the formula ##STR2## wherein R.sub.1, R.sub.2, R.sub.3, R.sub.3 ', R.sub.4 and R.sub.4 ' are as defined above, to thermal isomerization to give a vitamin D.sub.

Abstract: There are disclosed novel derivatives of 26,26,26,27,27,27-hexafluorovitamin D.sub.3 having fluorine atom at the 23- and/or 24-position which have an excellent pharmacological activity and a process for production thereof. The novel compounds are represented by the general formula: ##STR1## wherein R.sub.1 ' denotes a hydrogen atom, a hydroxyl group or a protected hydroxyl group, R.sub.2 denotes a hydrogen atom or a protecting group for hydroxyl group, R.sub.3 denotes a hydrogen atom, a fluorine atom, a hydroxyl group or a protected hydroxyl group and R.sub.4 and R.sub.4 ' each denotes a hydrogen atom, or one of them denotes a hydrogen atom and the other denotes a fluorine atom, hydroxyl group or a protected hydroxyl group or R.sub.4 and R.sub.4 ' are combined to denote an oxo group, with a proviso that at least one of R.sub.3, R.sub.4 and R.sub.4 ' denote a fluorine atom.

Abstract: In an air conditioning system, a damper unit disposed in the middle of a circulating duct is controlled so that a throttle valve of at least one of air quantity regulating devices for controlling incoming outside air quantity and exhaust air quantity is fully open, and that the quantity of air passing through the device whose throttle valve is fully open is equal to a set air quantity. The control system for the damper unit is so-called floating control system that is responsive to the control conditions. If none of the throttle valves of the devices is fully open, then there must be too great a pressure difference to pass the set quantity of air through all the devices. Accordingly, the excessive pressure applied to the devices can be lowered to a proper level by driving the damper unit in an opening direction, thereby reducing pressure loss between the discharging and charging blowers.