Patents - stay tuned to the technology

Inventors list

Assignees list

Classification tree browser

Top 100 Inventors

Top 100 Assignees


Hiroyuki Nakamura, Osaka JP

Hiroyuki Nakamura, Osaka JP

Patent application numberDescriptionPublished
20080315973SURFACE ACOUSTIC WAVE FILTER, BOUNDARY ACOUSTIC WAVE FILTER, AND ANTENNA DUPLEXER USING SAME - A surface acoustic wave filter includes a piezoelectric substrate including lithium niobate, a series resonator including a first interdigital transducer electrode provided on the piezoelectric substrate, and a parallel resonator including a second interdigital transducer electrode provided on the piezoelectric substrate and being electrically connected to the series resonator. An apodized weighting factor of the first interdigital transducer electrode is smaller than an apodized weighting factor of the second interdigital transducer electrode. This surface acoustic wave filter has a small loss.12-25-2008
20090102319ACOUSTIC RESONATOR AND FILTER - A first supporting section 04-23-2009
20090104951WIRELESS CIRCUIT DEVICE - A current control circuit (04-23-2009
20090134958SURFACE ACOUSTIC WAVE FILTER AND SURFACE ACOUSTIC WAVE DUPLEXER - A surface acoustic wave filter which includes a first terminal at the input side, a second terminal at the output side, a plurality of resonators electrically connected between the first and the second terminals, and a piezoelectric substrate provided on the upper surfaces of first and second terminals and the plurality of resonators. The piezoelectric substrate is made to have a thickness that is not thicker than 0.2 mm. The filtering characteristic of surface acoustic wave filter can be improved by taking advantage of the above structure.05-28-2009
20090267447ACOUSTIC WAVE DEVICE - An acoustic wave device includes a piezoelectric substrate having a surface adapted to allow leaky surface wave to propagate thereon, an interdigital electrode provided on a portion of the surface of the piezoelectric substrate, and a dielectric layer provided on the surface of the piezoelectric substrate to cover the interdigital electrode. The piezoelectric substrate is made of lithium niobate. The dielectric layer is made of tantalum pentoxide. The piezoelectric substrate is made of a rotated Y-cut substrate having a cut angle which is not smaller than 2.5 degrees and is not larger than 22.5 degrees. A ratio H/λ of a film thickness H of the dielectric layer to a wavelength λ of a center frequency of the leaky surface wave ranges from 0.034 to 0.126. This acoustic wave device works in a wide band width.10-29-2009
20090267449ELASTIC WAVE DEVICE AND FILTER AND ELECTRONIC EQUIPMENT USING THE DEVICE - The elastic wave device of the present invention has an piezoelectric substrate; a first dielectric layer disposed on the piezoelectric substrate; a second dielectric layer disposed on the first dielectric layer; and an acoustical layer on the second dielectric layer. Determining each film thickness of the first and the second dielectric layers provides advantageous effects. That is, energy of an SH wave as a main wave is confined in the boundary between the piezoelectric substrate and the first dielectric layer, and at the same time, an SV wave is suppressed as an unwanted wave. The device allows the SV wave—whose displacement distribution is similar to that of Stoneley wave—to have displacement distribution on the upper surface of the second dielectric layer and to be suppressed by the acoustical layer disposed on the second dielectric layer.10-29-2009
20100060102ACOUSTIC WAVE DEVICE AND ELECTRONIC EQUIPMENT USING THE SAME - An acoustic wave device has: a piezoelectric body; an interdigital electrode that is arranged on the piezoelectric body and excites an acoustic wave; and a dielectric layer that is arranged on the piezoelectric body so as to cover the interdigital electrode. The dielectric layer includes a composition changing portion made up of a medium where propagation velocity of a transverse wave continuously increases upward. With this configuration, it is possible to shift a spurious radiation by a high-order mode that propagates inside the dielectric layer to a higher frequency, so as to reduce an influence of the spurious radiation by the high-order mode.03-11-2010
20100060103SURFACE ACOUSTIC WAVE RESONATOR - A surface acoustic wave resonator of the present invention includes a piezoelectric substrate (03-11-2010
20100097161SURFACE ACOUSTIC WAVE FILTER, ANTENNA DUPLEXER AND METHOD FOR MANUFACTURING THEM - A surface acoustic wave filter comprised of a plurality of surface acoustic wave resonators having different resonance frequencies, the filter comprising a substrate made of a lithium niobate, comb electrodes (04-22-2010
20100164646SURFACE ACOUSTIC WAVE DEVICE, SURFACE ACOUSTIC WAVE FILTER AND ANTENNA DUPLEXER USING THE SAME, AND ELECTRONIC EQUIPMENT USING THE SAME - A surface acoustic wave device includes a substrate including lithium niobate; a IDT being provided on an upper surface of the substrate and including a plurality of electrode fingers; and a protective film covering the IDT and having an uneven shape on an upper surface thereof. When a pitch width of one pitch of the IDT is p, a width of one of the electrode fingers is p07-01-2010
20100188165ANTENNA DUPLEXER AND COMMUNICATION APPARATUS EMPLOYING THE SAME - A small antenna duplexer that includes antenna terminal, first filter electrically connected to this antenna terminal and passing a first frequency band, second filter electrically connected to antenna terminal and passing a second frequency band, and third filter electrically connected to antenna terminal and passing a third frequency band. First filter and third filter are used for one band, and second filter and third filter are used for another band.07-29-2010
20100194496ELASTIC WAVE RESONATOR, ELASTIC WAVE FILTER, AND ANTENNA SHARING DEVICE USING THE SAME - An acoustic wave resonance device includes: piezoelectric substrate (08-05-2010
20100219718BOUNDARY ACOUSTIC WAVE DEVICE - A boundary acoustic wave device includes a first medium layer made of piezoelectric material, a second medium layer provided on the first medium layer, a third medium layer provided on the second medium layer, and an electrode provided at an interface between the second and third medium layers. The electrode drives the third medium layer to generate a transverse wave. A propagation speed of the transverse wave in the third medium layer is lower than a propagation speed of the transverse wave in the first medium layer. A propagation speed of the transverse wave in the second medium layer is lower than the propagation speed of the transverse wave in the first medium layer. This boundary acoustic wave device has a large electro-mechanical coupling coefficient.09-02-2010
20100219901DUPLEXER - A duplexer according to the present invention includes: an acoustic wave element having a first terminal and a second terminal; a substrate mounting the acoustic wave element on the surface; a first columnar conductor electrically connected to the first terminal, and drawn to a back surface of the substrate, while being buried partially in the substrate; a second columnar conductor electrically connected to the second terminal, and drawn to the back surface of the substrate, while being buried partially in the substrate; a first ground pattern region arranged between the first columnar conductor drawn part and the second columnar conductor drawn part on the back surface of the substrate; a second ground pattern region electrically connected to the first ground pattern region on the back surface of the substrate and arranged in the part not including the part between the first columnar conductor drawn part and the second columnar conductor drawn part; and a third columnar conductor electrically connected to the first ground pattern region, while being buried partially in the substrate.09-02-2010
20100219905SURFACE ACOUSTIC WAVE RESONATOR, AND SURFACE ACOUSTIC WAVE FILTER AND ANTENNA DUPLEXER IN WHICH THE SURFACE ACOUSTIC WAVE RESONATOR IS USED - The present invention provides a surface acoustic wave resonator capable of improving the leak of a surface acoustic wave in the transverse direction and reducing the spurious and having superior characteristics. In a surface acoustic wave filter according to the present invention, an interdigital transducer electrode and reflector electrodes are formed on a piezoelectric substrate, and a SiO09-02-2010
20100231089SURFACE ACOUSTIC WAVE DEVICE AND MANUFACTURING METHOD OF THE SAME SURFACE ACOUSTIC WAVE DEVICE - A surface acoustic wave device includes a piezoelectric element, an IDT electrode formed on the piezoelectric element for exciting a principal wave, a reflection film formed on the piezoelectric element having a higher reflectivity than the reflectivity of the piezoelectric element in a visible light wavelength region, and a light permeable dielectric layer formed on the piezoelectric element, at least a part of the IDT electrode, and the reflection film. Accordingly, when measuring the film thickness of the light permeable dielectric layer by light interference method, the reflected light from the reflection film having a higher reflectivity than the reflectivity of the piezoelectric element in a visible light wavelength region can be utilized, so that the film thickness can be measured more accurately.09-16-2010
20110001578SURFACE ACOUSTIC WAVE FILTER AND DUPLEXER USING THE SAME - A SAW filter includes a piezoelectric body, an IDT electrode on the piezoelectric body, and signal wiring electrically connected to the IDT electrode. The signal wiring has a thickness not less than a skin depth specified based on the frequency of a signal passing through the signal wiring and the electrical conductivity of the signal wiring. As a result, the signal wiring has low propagation loss of the signal passing through it, so that the SAW filter has excellent transmission characteristics.01-06-2011
20110006855ELASTIC WAVE FILTER, AND DUPLEXER AND ELECTRONIC DEVICE USING SAME - An elastic wave filter has first, second, and third IDT electrodes whose wiring electrodes are connected to unbalanced signal terminal; fourth IDT electrode disposed between the first and second IDT electrodes; fifth IDT electrode disposed between the second and third IDT electrodes; and first and second balanced signal terminals connected to the wiring electrodes of fourth and fifth IDT electrodes, respectively. The ground electrodes of the first through fifth IDT electrodes are connected to the ground. Signals in opposite phase and in phase with a signal input to unbalanced signal terminal are output from first and second balanced signal terminals, respectively. The wiring electrodes of second and third IDT electrodes are adjacent to the ground electrode of fifth IDT electrode. The wiring electrode of one of first and second IDT electrodes is adjacent to the wiring electrode of fourth IDT electrode. The ground electrode of the other is adjacent to the ground electrode of fourth IDT electrode. This configuration can suppress spuriousness in the bandpass.01-13-2011
20110043428ANTENNA DUPLEXER AND COMMUNICATION DEVICE USING THE SAME - An antenna duplexer includes a transmission filter and a reception filter both coupled with an antenna terminal. A pass band of the transmission filter is lower than a pass band of the reception filter. The transmission filter includes a first series resonator coupled with a first terminal, a second series resonator connected to the first series resonator at a first node, a first parallel resonator connected to a first port of the first series resonator, a second parallel resonator connected to a first node and the first parallel resonator at a second node, a third parallel resonator connected to the first node, a fourth parallel resonator connected to the third parallel resonator at a third node, a first inductance element coupled with the second node and a ground, and a second inductance element coupled with the third node and the ground. The first and second parallel resonators and the first inductance element produce an attenuation pole at a frequency lower than a pass band of the transmission filter. The third and fourth parallel resonators and the second inductance element produce an attenuation pole at a frequency higher than a pass band of the transmission filter. The inductance of the second inductance element is lower than the inductance of the first inductance element. In this antenna duplexer, the transmission filter sufficiently suppresses a spurious caused by harmonics contained in a transmission signal.02-24-2011
20110063046SURFACE ACOUSTIC WAVE FILTER DEVICE, DUPLEXER INCLUDING THE SAME, AND ELECTRONIC APPARATUS INCLUDING THE SAME - A surface acoustic wave (SAW) filter device includes an input port for receiving an unbalanced signal, a pair of input/output ports, a first SAW filter for receiving the unbalanced signal from the input port and outputting balanced signals to the pair of input/output ports, a second SAW filter for receiving the balanced signals output from the pair of input/output ports and outputting balanced signals, and a pair of output ports for outputting the balanced signals output from the second SAW filter. The first SAW filter includes a first longitudinally-coupled SAW resonator having a first unbalanced signal input port and first and second balanced signal output ports, and a second longitudinally-coupled SAW resonator having a second unbalanced signal input port and third and fourth balanced signal output port. The first and second unbalanced signal input ports are electrically connected to the input port. The first and third balanced signal output ports both are electrically connected to one of the pair of input/output ports. The second and fourth balanced signal output ports both are electrically connected to another of the pair of input/output ports. This SAW filter device can suppress spurious and has a small insertion loss.03-17-2011
20110068881ACOUSTIC WAVE FILTER - An acoustic wave filter includes a first IDT electrode, a second IDT electrode, and a third IDT electrode. The first IDT electrode includes a first signal electrode finger connected to the unbalanced terminal, and a first ground electrode finger. The second IDT electrode includes a second signal electrode finger connected to a first balanced terminal, and a second ground electrode finger. The third IDT electrode includes a third signal electrode finger connected to the second balanced terminal, and a third ground electrode finger. A dummy electrode finger connected neither to the unbalanced terminal nor to the ground is provided on the second IDT electrode side in the first IDT electrode. Thus, the degree of balance between balanced terminals can be improved.03-24-2011
20110095845ACOUSTIC WAVE DUPLEXER - An acoustic wave duplexer includes a piezoelectric substrate, a first filter and a second filter whose center frequency is higher than that of the first filter, the first and second filters being provided on the piezoelectric substrate. The first filter is structured as a ladder type. A resonator positioned nearest to an antenna terminal out of series-arm resonators is designated as a first resonator. A pitch of a comb-shaped electrode structuring the first resonator is set such that a bulk wave emission frequency of the first resonator becomes higher than a passband of the second filter.04-28-2011
20110109196PLATE WAVE ELEMENT AND ELECTRONIC EQUIPMENT USING SAME - A plate wave element includes a piezoelectric body, a comb-shaped electrode disposed on an upper surface of the piezoelectric body, and a medium layer disposed on the upper surface of the piezoelectric body so as to cover the comb-shaped electrode. The comb-shaped electrode excites a Lamb wave as a main wave. The medium layer has a frequency temperature characteristic opposite to that of the piezoelectric body. The plate wave element has a preferable frequency temperature characteristic.05-12-2011
20110133858ELASTIC WAVE ELEMENT AND ELECTRONIC DEVICE USING THE SAME - An elastic wave device includes a piezoelectric substrate, an IDT electrode disposed on a piezoelectric device, a first dielectric layer disposed on the piezoelectric substrate such that it covers the IDT electrode, and a second dielectric layer disposed over the first dielectric layer. The second dielectric layer propagates transverse waves faster than that on the first dielectric layer. When a film thickness of the second dielectric layer is greater than a wave length of a major wave excited by the IDT electrode, a cut angle of the piezoelectric substrate in indication of Euler angles (φ, θ, Φ) is set to φ≠0°, θ≠0°, and Φ≠0°. This suppresses deterioration of device characteristics.06-09-2011
20110156837ACOUSTIC WAVE DEVICE, AND FILTER AND DUPLEXER USING THE SAME - An acoustic wave device includes a piezoelectric substrate, an IDT electrode provided on the piezoelectric substrate, a dielectric layer provided so as to cover the IDT electrode, and a first stress relaxation layer provided on the dielectric layer. Furthermore, the acoustic wave device includes an extraction electrode connected to the IDT electrode and extracted onto the first stress relaxation layer, and a bump provided on the extraction electrode. An elastic modulus of the first stress relaxation layer is smaller than that of the dielectric layer.06-30-2011
20110193655ACOUSTIC WAVE DEVICE AND ACOUSTIC WAVE FILTER - An acoustic wave device includes an interdigital transducer (IDT) electrode and a separate electrode facing the IDT electrode. The IDT electrode includes first and second comb-shaped electrode facing each other. The first comb-shaped electrode includes a first bus bar, first interdigitated electrode fingers, and first dummy electrode fingers. The second comb-shaped electrode includes a second bus bar second interdigitated electrode fingers interdigitated with the first interdigitated electrode fingers, second dummy electrode fingers facing the first interdigitated electrode fingers, weighted parts, and a non-weighted part. The weighted parts have electrodes at spaces between the second interdigitated electrode fingers and the second dummy electrode fingers. In the non-weighted part, there is no electrode at a space out of the spaces which is closest to the separate electrode in the non-interdigitated region. This acoustic wave device prevents short circuits between the IDT electrode and the separate electrode, and provides excellent characteristics of suppressing unwanted waves.08-11-2011
20110204998ELASTIC WAVE ELEMENT AND ELECTRONIC DEVICE USING THE SAME - Offers elastic wave device that has convex portion on the top face of first dielectric layer over IDT electrode when elastic wave device has a structure of a boundary wave device in which a film thickness of second dielectric layer is not less than 1.6 times as much as pitch width p of IDT electrode. This convex portion increases an electromechanical coupling coefficient of SH wave that is the major wave. Accordingly, good filter characteristics can be easily achieved.08-25-2011
20110215883ACOUSTIC WAVE RESONATOR AND ACOUSTIC WAVE FILTER USING THE SAME - An acoustic wave resonator includes a piezoelectric substrate and first and second comb-shaped electrodes provided on the piezoelectric substrate and interdigitating with each other. The first comb-shaped electrode includes a first busbar and first electrode fingers extending in a direction non-perpendicular to a direction in which the first busbar extends. The second comb-shaped electrode includes a second busbar and second electrode fingers extending from the second busbar and interdigitating with the first electrode fingers at an interdigitating region. This acoustic wave resonator can suppress a spurious response due to a transverse mode and has a high Q value.09-08-2011
20110215884LADDER-TYPE FILTER - A ladder-type filter having plural elastic-wave resonators provided on a series arm and a parallel arm in a ladder shape on a piezoelectric substrate. Each of the elastic-wave resonators has an interdigital electrode. The interdigital electrode has plural electrode finger pairs formed of electrode fingers extending from first and second bus bars. The interdigital electrode included in the elastic-wave resonator provided on the parallel arm has an electrode cross width of the electrode fingers extending from the first and second bus bars 23 times or more of the wavelength of elastic waves excited by the interdigital electrodes.09-08-2011
20120019102ELASTIC WAVE ELEMENT AND ELECTRONIC APPARATUS USING SAME - An acoustic wave element includes a piezoelectric body, first and second interdigital transducer (IDT) electrodes provided on an upper surface of the piezoelectric body, and a first dielectric layer provided on the upper surface of the piezoelectric body to cover the first and second IDT electrodes. The first dielectric layer has a first part directly above the first IDT electrode and a second part directly above the second IDT electrode. The height of an upper surface of the second part of the first dielectric layer is larger than the height of an upper surface of the first part of the first dielectric layer. This acoustic wave element has a preferable temperature characteristic and electromechanical coupling factor,01-26-2012
20120044027ACOUSTIC WAVE RESONATOR AND DUPLEXER USING SAME - An acoustic wave resonator includes a piezoelectric body, an IDT electrode for exciting an acoustic wave with wavelength λ, and a dielectric thin film provided so as to cover the IDT electrode. The IDT electrode includes a bus bar electrode region, a dummy electrode region, and an IDT cross region in order from outside. The film thickness of the dielectric thin film above at least one of the bus bar electrode region and the dummy electrode region is smaller than that above the IDT cross region by 0.1λ to 0.25λ. This configuration provides an acoustic wave resonator that reduces transverse-mode spurious emission.02-23-2012
20120062337ANTENNA SHARING DEVICE - The antenna sharing device has a first elastic-wave filter for passing signals of a first frequency passband and a second elastic-wave filter for passing signals of a second frequency passband higher than the first frequency passband. The first elastic-wave filter is a ladder-type filter including a first series resonator and a second series resonator having an antiresonant frequency point higher than that of the first series resonator. The first series resonator has a first IDT electrode and a first dielectric film covering the electrode. The second series resonator has a second IDT electrode and a second dielectric film covering the electrode. The first and the second dielectric films have a first projection and a second projection, respectively, so as to be formed above the electrode fingers of each IDT electrode. The cross-sectional area of the first projection of the first series resonator is larger than that of the second projection of the second series resonator in the excitation direction of the elastic wave. The structure satisfies both of steepness in a crossband and low loss in a passband.03-15-2012
20120086521LADDER TYPE SURFACE ACOUSTIC WAVE FILTER AND DUPLEXER USING SAME - An object of the present invention is to improve the passing characteristic at high temperature in a ladder-type elastic wave filter and a duplexer including the filter. The ladder-type elastic wave filter of the present invention includes a piezoelectric substrate, a first series elastic-wave resonator formed on the piezoelectric substrate and connected in series between the input and output terminals of the filter, a parallel elastic-wave resonator formed on the piezoelectric substrate and connected in parallel between the series elastic-wave resonator and the ground terminal, and a dielectric film formed on the piezoelectric substrate so as to cover the first series elastic-wave resonator. The piezoelectric substrate is formed of a material with a negative temperature coefficient. The dielectric film is formed of a material with a positive temperature coefficient and its film thickness is formed thicker than that with which the frequency-temperature coefficient of the first series elastic-wave resonator becomes 0.04-12-2012
20120139662ELASTIC WAVE ELEMENT, AND ELECTRICAL APPARATUS AND DUPLEXER USING SAME - An acoustic wave device (06-07-2012
20120146457ACOUSTIC WAVE ELEMENT AND ACOUSTIC WAVE ELEMENT SENSOR - An acoustic wave element includes a piezoelectric body, an input IDT electrode, an output IDT electrode, a propagation path provided between the input IDT electrode and the output IDT electrode, a first dielectric layer provided on the piezoelectric body so as to cover the input IDT electrode and the output IDT electrode, and a reactive portion provided on the propagation path and reacting to a substance to be detected or a binding substance that binds with the substance to be detected. The main acoustic wave becomes, in the input IDT electrode and the output IDT electrode, a boundary acoustic wave that propagates between the piezoelectric body and the first dielectric layer, and becomes, in the propagation path, a surface acoustic wave that propagates on an upper surface of the propagation path. With this structure, deterioration of the element characteristic is suppressed.06-14-2012
20120188026ANTENNA DUPLEXER - An antenna duplexer includes first and second filters connected to an antenna terminal. The first filter has a passband of a low frequency band. The second filter has a passband of a high frequency band. The second filter is a ladder-type filter including series-arm resonators and parallel-arm resonators. At least one parallel-arm resonator out of the parallel-arm resonators has a main resonance and an auxiliary resonance. Attenuation poles caused by the main resonance and the auxiliary resonance are within the low frequency band. This antenna duplexer has a high attenuation characteristic and a high isolation characteristic while maintaining a low insertion loss.07-26-2012
20120218052ANTENNA SHARING DEVICE - Antenna duplexer (08-30-2012
20120223789ELASTIC-WAVE FILTER DEVICE AND COMPOSITE DEVICE INCLUDING THE SAME - An elastic-wave filter device includes a first piezoelectric substrate, a second piezoelectric substrate, a first pillar-like wiring electrode, and a second pillar-like wiring electrode. The first and second substrates have a first and a second IDT electrodes on their top faces respectively. A lateral face of the second substrate confronts a lateral face of the first substrate. The first pillar-like electrode and the second pillar-like electrode are formed above the first and the second substrates respectively, and are electrically connected to the first and the second IDT electrodes respectively. The first substrate is thicker than the second substrate. A distance between a plane including the top face of the first substrate and a plane including the top face of the second substrate is smaller than a distance between a plane including an underside of the first substrate and a plane including an underside of the second substrate.09-06-2012
20120313724ELASTIC WAVE FILTER DEVICE AND ANTENNA DUPLEXER USING SAME - An elastic wave filter device includes a longitudinally coupled resonator-type elastic wave filter formed on a piezoelectric substrate; and a ladder-type elastic wave filter connected to the resonator-type elastic wave filter. The resonator-type filter includes an input IDT and an output IDT. The ladder-type filter includes a series arm resonator and a parallel arm resonator. A first ground electrode connected to the parallel arm resonator is electrically separated from a second ground electrode connected to at least one of the input IDT and the output IDT.12-13-2012
20120326801DUPLEXER - A duplexer includes an acoustic wave element having a first terminal and a second terminal; a substrate; a first columnar conductor electrically connected to the first terminal, and drawn to a back surface of the substrate while partially in the substrate; a second columnar conductor electrically connected to the second terminal, and drawn to the back surface of the substrate while partially in the substrate. Additionally, a first ground pattern region is between the first columnar conductor drawn part and the second columnar conductor drawn part on the back surface of the substrate; a second ground pattern region is electrically connected to the first ground pattern region and arranged in the part not including the part between the first columnar conductor drawn part and the second columnar conductor drawn part; and a third columnar conductor electrically is connected to the first ground pattern region while partially in the substrate.12-27-2012
20130026881ACOUSTIC WAVE ELEMENT - An IDT electrode includes a first electrode layer mainly made of Mo disposed above the piezoelectric body and a second electrode layer mainly made of Al disposed above the first electrode layer. The IDT electrode has a total thickness not more than 0.15λ. The first electrode layer has a thickness not less than 0.05λ. The second electrode layer has a thickness not less than 0.025λ.01-31-2013
20130099875ACOUSTIC WAVE DEVICE AND ANTENNA DUPLEXER EMPLOYING THE SAME - The present invention is an acoustic wave device including first and second acoustic wave resonators. A first tilt angle that is an angle formed between a direction perpendicular to a direction in which electrode fingers of the first acoustic wave resonator extend and a direction along which the electrode fingers are arranged is different from a second tilt angle that is an angle formed between a direction perpendicular to a direction in which electrode fingers of the second acoustic wave resonator extend and a direction along which the electrode fingers are arranged.04-25-2013
20130162368LADDER-TYPE SURFACE ACOUSTIC WAVE FILTER AND DUPLEXER INCLUDING THE SAME - A ladder-type surface acoustic wave filter includes a first series resonator having the lowest resonance frequency among a plurality of series resonators; and a second series resonator having a resonance frequency higher than the first series resonator. The film thickness of a dielectric film in the region where the first series resonator is formed is larger than that of a dielectric film in the region where the second series resonator is formed.06-27-2013
20130210374ANTENNA DUPLEXER AND COMMUNICATION DEVICE USING THE SAME - An antenna duplexer includes a transmission filter and a reception filter both coupled with an antenna terminal. A pass band of the transmission filter is lower than a pass band of the reception filter. The transmission filter includes a first series resonator coupled with a first terminal, a second series resonator connected to the first series resonator at a first node, a first parallel resonator connected to a first port of the first series resonator, a second parallel resonator connected to a first node and the first parallel resonator at a second node, a third parallel resonator connected to the first node, a fourth parallel resonator connected to the third parallel resonator at a third node, a first inductance element coupled with the second node and a ground, and a second inductance element coupled with the third node and the ground. The inductance of the second inductance element is lower than the inductance of the first inductance element. In this antenna duplexer, the transmission filter sufficiently suppresses a spurious caused by harmonics contained in a transmission signal.08-15-2013
20130214872ELASTIC WAVE FILTER, AND DUPLEXER AND ELECTRONIC DEVICE USING SAME - An elastic wave filter has first, second, and third IDT electrodes whose wiring electrodes are connected to unbalanced signal terminal; fourth IDT electrode disposed between the first and second IDT electrodes; fifth IDT electrode disposed between the second and third IDT electrodes; and first and second balanced signal terminals connected to the wiring electrodes of fourth and fifth IDT electrodes, respectively. The ground electrodes of the first through fifth IDT electrodes are connected to the ground. Signals in opposite phase and in phase with a signal input to unbalanced signal terminal are output from first and second balanced signal terminals, respectively. The wiring electrodes of second and third IDT electrodes are adjacent to the ground electrode of fifth IDT electrode. The wiring electrode of one of first and second IDT electrodes is adjacent to the wiring electrode of fourth IDT electrode. The ground electrode of the other is adjacent to the ground electrode of fourth IDT electrode. This configuration can suppress spuriousness in the bandpass.08-22-2013
20130249647ACOUSTIC WAVE DEVICE WITH REDUCED HIGHER ORDER TRANSVERSE MODES - In an acoustic wave device, a high-order transverse mode wave which is an unnecessary wave is suppressed. The acoustic wave device includes: a piezoelectric substrate; at least one pair of IDT electrodes formed on the piezoelectric substrate; and a dielectric film which covers at least a part of the piezoelectric substrate and the IDT electrodes, and the IDT electrodes each has a plurality of electrode fingers. The dielectric film covers at least an area in which the electrode fingers are arranged interleaved with each other. An acoustic velocity of an acoustic wave in an intersection area, within the region, which is a portion from ends of the electrode fingers to a predetermined length or more inward from the ends, is greater than an acoustic velocity of an acoustic wave in an edge area including end portions of the electrode fingers.09-26-2013
20140001919ELASTIC WAVE ELEMENT01-02-2014
20140049341MULTIMODE ELASTIC WAVE DEVICE - A multimode elastic wave device includes a pair of reflectors, and a first interdigital transducer (IDT) electrode through a fifth IDT electrode arranged between the pair of reflectors. In this configuration, each of the average of electrode-finger pitches in the first IDT electrode and the average of electrode-finger pitches in the fifth IDT electrode is smaller than both of the average of electrode-finger pitches in the second IDT electrode and the average of electrode-finger pitches in the fourth IDT electrode.02-20-2014
20140113571ELECTRONIC DEVICE INCLUDING FILTER - An electronic device includes a main circuit connected between an input terminal and an output terminal, and an auxiliary circuit connected in parallel to the main circuit between the input terminal and the output terminal. The main circuit includes a filter having a first passband and a stopband. The auxiliary circuit has a passing characteristic that allows a signal having a frequency in a certain frequency band inside the stopband to pass through the auxiliary circuit. The main circuit is configured to output a main signal in response to an input signal. The auxiliary circuit is configured to output an auxiliary signal in response to the input signal. The main signal and the auxiliary signal contain phase components opposite to each other in the certain frequency band inside the stopband. This electronic device has an attenuation amount in the stopband.04-24-2014
20140144237ELASTIC WAVE SENSOR - An acoustic wave sensor includes a piezoelectric substrate, a transmitting electrode configured to excite a main acoustic wave propagating through a propagation region of an upper surface of the piezoelectric substrate, a receiving electrode configured to receive the propagated main acoustic wave, a first insulating film provided on the propagation region of the upper surface of the piezoelectric substrate, a second insulating film provided on the upper surface of the piezoelectric substrate to cover the first insulating film, and a reaction section provided on the upper surface of the second insulating film above the propagation region. The reaction section is configured to react with an object. A velocity of a transverse wave propagating through the first insulating film is higher than a velocity of a transverse wave propagating through the second insulating film. The acoustic wave sensor described above has high detection sensitivity.05-29-2014
20140167877FILTER MODULE - In a filter module capable of handling multiple bands, cross wiring with an RF-IC is to be solved. The filter module includes: an antenna terminal; first and second transmission filters; first and second reception filters; a first switch circuit connected to the antenna terminal, and selectively connected to the first and second transmission filters; a second switch circuit connected to the antenna terminal, and selectively connected to the first and second reception filters; a first matching circuit connected between the first switch circuit and the first transmission filter or between the second switch circuit and the first reception filter; and a second matching circuit connected between the first switch circuit and the second transmission filter or between the second switch circuit and the second reception filter.06-19-2014
20140167881ACOUSTIC WAVE DEVICE AND ANTENNA DUPLEXER USING THE SAME - An acoustic wave device includes a piezoelectric substrate, a comb-shaped electrode formed on the piezoelectric substrate and configured to excite a Rayleigh wave as a main acoustic wave, a first dielectric film formed above the piezoelectric substrate to cover the comb-shaped electrode, and a second dielectric film having a portion provided between electrode fingers of the comb-shaped electrode and a portion provided above the comb-shaped electrode. The portion provided between the electrode fingers is provided between the piezoelectric substrate and the first dielectric film. The portion provided above the comb-shaped electrode is provided between the comb-shaped electrode and the first dielectric film. A speed of a transverse wave propagating through the first dielectric film is lower than a speed of the Rayleigh wave excited by the comb-shaped electrode. A speed of a transverse wave propagating through the second dielectric film is higher than the speed of Rayleigh wave excited by the comb-shaped electrode.06-19-2014
20140218129LADDER-TYPE ELASTIC WAVE FILTER AND ANTENNA DUPLEXER USING SAME - In a ladder-type elastic wave filter, a resonance frequency of a second parallel resonator is higher than that of a series resonator and lower than an antiresonance frequency of a series resonator. With this configuration, an attenuation pole is formed by the second parallel resonator at a frequency region lower than an attenuation pole formed by the series resonator in a frequency region higher than the passband of the ladder-type elastic wave filter.08-07-2014
20140232239ACOUSTIC WAVE DEVICE AND ELECTRONIC APPARATUS INCLUDING SAME - An acoustic wave device includes a piezoelectric substrate, an IDT electrode including plural electrode fingers disposed above an upper surface of the piezoelectric substrate, a first dielectric film made of oxide disposed above the upper surface of the substrate for covering the electrode fingers, and a second dielectric film made of non-oxide disposed on upper surfaces of the electrode fingers and between the first dielectric film and each of the electrode fingers. The first dielectric film contacts the upper surface of the piezoelectric substrate at a position between electrode fingers out of the plural electrode fingers adjacent to each other. The acoustic wave device prevents the electrode fingers of the IDT electrode from corrosion.08-21-2014
20140285287ACOUSTIC WAVE DEVICE - An acoustic wave device includes a piezoelectric substrate, an interdigital transducer (IDT) electrode provided on an upper surface of the piezoelectric substrate, a first dielectric film covering the upper surface of the piezoelectric substrate to cover the IDT electrode, and a second dielectric film covering an upper surface of the first dielectric film. The second dielectric film includes a thin portion positioned in a tip region of electrode fingers of the IDT electrode and a thick portion which is positioned in a middle region of the IDT electrode and is thicker than the thin portion. The acoustic wave device suppresses spurious emission and has superior passband characteristics.09-25-2014

Patent applications by Hiroyuki Nakamura, Osaka JP

Website © 2015 Advameg, Inc.