Abstract: A piezoelectric transformer with multiple outputs comprises a piezoelectric plate, a first input electrode being formed on the top surface of the piezoelectric plate, a second input electrode being formed on the bottom surface of the piezoelectric plate, a plurality of first output electrodes being electrically isolated from each other, being formed on the equally divided remaining portions of the top surface of the plate along a diagonal line, and a second output electrode formed on the remaining portions of the bottom surface of the plate, thereby providing a stabilizer for lighting lamps without a ballast capacitor by supplying a regular voltage to more than two fluorescent lamps.

Abstract: In a piezoelectric resonator utilizing bending vibrations, three or more electrode layers and two or more piezoelectric layers are alternately laminated, at least two layers of the piezoelectric layers are polarized in the thickness direction, first and second end surface electrodes are provided in the end surfaces of the laminated piezoelectric layers, and the electrode layers are connected to each other by using the first and second end surface electrodes such that, in at least one piezoelectric layer, an electric field is generated in the same direction as the polarization direction of the piezoelectric layer, and such that, in at least one of the other piezoelectric layers, an electric field is generated in a direction that is opposite to the polarization direction of the piezoelectric layer.

Abstract: Transducer elements having a 2—2 or 1-3 composite structure and driven in a k31 transverse mode for small-feature size transducer arrays, which provide improved electrical impedance matching to an ultrasonic imaging system and improved acoustic matching to the human body. The transducer element includes a plurality of thin piezoceramic wafers which are electroded on opposing major surfaces. The spaced wafers are separated by a passive polymer layer in a composite structure. Methods of producing the transducer elements are also described.

Abstract: A polarization apparatus is provided wherein a piezoelectric body tube 3 is wound around a first rotation drum 5 and a second rotation drum 6 and a coaxial flexible piezoelectric body 2 is polarized while the piezoelectric body tube 3 is wound. According to the polarization apparatus, polarization can be conducted except for the coaxial flexible piezoelectric body 2 of the portion containing a defect and a defect existing in the piezoelectric body tube 3 of a given length can also be detected before an outer electrode 4 is formed.

Abstract: Piezoelectric transformers have a number of favorable characteristics over traditional electromagnetic tranformers. However, the construction of piezoelectric transformers tends to be complicated, which may result in increasing manufacturing cost. Furthermore, such complex constructions may raise difficulties in the miniaturization of such devices. A ring-shaped piezoelectric transformer is developed in this invention for low voltage applications. One surface of the transformer is covered by two disc or ring-shaped electrodes separated by a ring-shaped separating segment, and the regions covered by the disc or ring-shaped electrodes served as the input and output parts of the transformer. This transformer may be fabricated relatively easily due to its simple structure. Furthermore, its size and thickness may be reduced relatively easily without increasing the difficulty of the fabricating process. The transformer may be used separately or in parallel.

Abstract: Multiple outputs can be efficiently generated in a piezoelectric transformer by utilizing both surfaces of a piezoelectric member at the primary side, and the piezoelectric member at the primary side is polarized in the direction of thickness or in the direction of length. The piezoelectric members at the secondary side applied with a polarization in the direction of thickness or in the direction of length are laminated on both surfaces of the piezoelectric member at the primary side in the direction of thickness or in the direction of length. When an alternating voltage is applied to the input terminals at the primary side, thickness vertical vibration is generated at the piezoelectric member at the primary side. The vertical wave vibration that propagates in the direction of thickness propagates to the piezoelectric members at the secondary side, and generates an alternating voltage by a piezoelectric positive effect.

Abstract: In order to polarize a piezoelectric material in high-temperature gas, a temperature-raising portion raises the temperature of the piezoelectric material to a temperature required to polarize the piezoelectric material. A constant-temperature bath has an atmosphere of the temperature of which is kept at the required temperature, and incorporates a polarizing portion that polarizes the piezoelectric material whose temperature is kept at the required temperature. When the temperature of the piezoelectric material is raised quickly to the temperature required to polarize the piezoelectric material by the temperature raising portion and is placed into the constant-temperature bath, the temperature of the piezoelectric material is at a temperature near a set temperature of the inside of the constant-temperature bath, so that the piezoelectric material can be polarized in a short period of time with high precision.

Abstract: A compact and wide band surface acoustic wave device for intermediate-frequency is disclosed. A piezoelectric substrate for use in a surface acoustic wave device having high electromechanical coupling factor and low SAW velocity is also disclosed.

Abstract: A resonator for applying vibrational energy to a member, for example a photoreceptor belt or developer/donor member, includes an energy transmitting horn member having a platform portion and a horn portion, the horn portion including a contacting portion for contacting a surface of the member, and a piezoelectric material in association with the horn member for driving the horn member to vibrate, the piezoelectric material responsive to a voltage signal from a voltage source. The piezoelectric material is a composite of at least one piezoceramic material and at least one of a polymer or air, and has a 1-3 configuration. By the selection of a piezoceramic/polymer composite material having the specified configuration for use as the vibratory energy producing source, or transducer, of a resonator, improved piezoelectric material performance is achieved, particularly with respect to control and/or elimination of undesired transverse vibration, and manufacturing complexity is reduced.

Abstract: A method of polarizing a piezoelectric body having a plurality of piezoelectric layers and internal electrodes which are alternately laminated, includes the steps of applying an electric field to the piezoelectric body to polarize the body uniformly in the thickness direction, applying electric field in the opposite directions to the piezoelectric layers on both sides of each internal electrode whereby the piezoelectric layer only on one side of the internal electrode is polarization-inverted. The polarization degree polarization is made uniform by the polarization-inversion.

Abstract: An optical actuator includes pairs of stators disposed parallel to each other with a stipulated gap between them, a mover disposed moveably within the gap, and a number of photovoltaic devices. The photovoltaic device has device electrodes on either end in the direction of polarization, each connected to one of the pair of stators. The voltage generated by the photovoltaic effect of the device is utilized to generate force that displaces the mover with respect to the stators by means of electrostatic force arising from the voltage.

Abstract: Mount terminals (32-34) formed on the end faces of a housing (31) in the longitudinal direction respectively abut against external electrodes (1, 2) which are formed on an end face of a piezoelectric element (6) in the longitudinal direction and used to apply input voltage, and an external electrode (3) for extracting output voltage. These abutted portions are fixed by soldering or with conductive adhesive to electrically connect the mount terminals to the external electrodes and fix the piezoelectric element (6) inside the housing (31).

Abstract: In the piezoelectric transformer for fluorescent lamp, the size of an electrode at the central region of each sides on the first face is smaller than that of electrode at the corner region. As a result, the stress generated in the piezoelectric block is minimized and the heat caused by the stress is prevented, so that the damage of the piezoelectric block and the deterioration of the efficient may be prevented. The input electrode can be formed in the various shapes such as diamond, cross, and rhombic shapes.

Abstract: In a multilayer piezoelectric actuator device having a laminated structure (3) of a plurality of piezoelectric elements (3a) and a plurality of internal electrodes (3b) alternately stacked, a pair of external electrodes (5) are connected alternately to said internal electrodes. Each of the external electrodes has an electrode layer (11) and a composite layer (13). The electrode layer is formed on a side surface of the laminated structure. The composite layer is formed on the electrode layer and made of a conductive resin including a conductive material. It is preferable that a carbon paper (7) is placed on the composite layer.

Abstract: A piezoelectric element contains a piezoelectric ceramic body having a layered perovskite structure, and has the C axis selected and oriented in the thickness direction. In the piezoelectric ceramic body, line shaped electrodes are formed perpendicular to the C axis selected and oriented. The electrodes exposed at both of the end faces of the piezoelectric ceramic body are covered with conductive materials and insulation materials. The piezoelectric ceramic body is polarized in the opposite directions on both of the sides of electrodes arranged in the width direction. Moreover, external electrodes are formed on the faces where the conductive materials and the insulation materials are formed, whereby two groups of the electrodes are arranged in an interdigital electrode form.

Abstract: A piezoelectric resonator includes a substantially rectangular shaped piezoelectric substrate having a pair of major surfaces and polarized in the thickness direction thereof and a pair of electrodes respectively disposed on the pair of major surfaces of the piezoelectric substrate. One of the electrodes is multiply divided along a dividing line which extends along the longitudinal direction of the piezoelectric substrate. The piezoelectric substrate is polarized such that two portions of the piezoelectric substrate sandwiching the dividing line are polarized in opposite directions.

Abstract: A single crystal perovskite material is provided having the formula, M&agr;Bi&bgr;M′&ggr;M″&dgr;O3±z, where M is one or more of Na, K, Rb and Cs; M′ is one or more of Ca, Sr, Ba, Pb, Y, La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu; and M″ is one or more of Ti, Zr, Hf, Sn, Ge, Mg, Zn, Al, Sc, Ga, Nb, Mo, Sb, Ta and W; where z≦0.1; 0.9≦&dgr;≦1.1; &agr;, &bgr; and &ggr; are greater than zero; and (&agr;+&bgr;+&ggr;) is in the range of about 0.75 to 1.1. A perovskite material of the formula, Na&ohgr;M&agr;Bi&bgr;M′&ggr;M″&dgr;O3±z, is provided where M is one or more of K, Rb and Cs; M′ is one or more of Ca, Sr, Ba, Pb, Y, La, Pr, Nd, Sm, Eu, Gd, Th, Dy, Ho, Er, Tm, Yb and Lu; M″ is one or more of Ti, Zr, Hf, Sn, Ge, Mg, Zn, Al, Sc, Ga, Nb, Mo, Sb, Ta and W; where z≦0.1; 0.9≦&dgr;≦1.1; &agr;, &bgr; and &ggr; are greater than zero; and (&agr;+&bgr;+&ggr;) is in the range of about 0.75 to 1.1.

Abstract: A method for manufacturing a cofired multi-layer piezoelectric transformer device includes forming first and second green shapes of a sinterable ceramic composition and applying metallization layer therebetween. Upon cofiring, the composite structure comprises first and second electroactive members bonded together by a conductive layer therebetween. External electrodes are applied and the electroactive members are polarized in a thickness direction, between their two major faces. The first and second electroactive members are arranged such that deformation of one electroactive member results in corresponding deformation of the other electroactive member. The device provides substantial transformation ratios in which relatively high power may be transferred in relation to the size of the unit, operability over wide input and output frequency bandwidths, and electrical isolation of the input voltage and current from the output voltage and current.

Abstract: Disclosed is a high voltage sensitivity coriolis force driven piezoelectric-gyroscope-transformer system, and method of its use. The system is of a preferably generally elongated rectangular solid shape and provides two stacked regions of oppositely polarized direction driving side piezoelectric material on a first longitudinally disposed side thereof, and two adjacent regions of longitudinally oppositely polarized direction sensing side piezoelectric material on a second longitudinally disposed side thereof. In use the system is caused to rotate about a essentially centrally located longitudinally oriented axis therethrough from the first longitudinally disposed side to the second, while a flex effecting driving voltage is applied across the two stacked regions of said oppositely polarization direction driving side piezoelectric material on the first longitudinally disposed side and an output voltage is sensed at the end of the second longitudinally disposed, sensing side.

Abstract: This invention relates to a new class of piezoelectric composites with a radial design. More particularly, the radial design of these new ceramic/polymer composites show a higher sensitivity in the radial direction than conventional tube structured devices. Devices made utilizing this novel design will therefore show significantly enhanced performance in many applications.

Abstract: Composites for actuating or sensing deformation. In embodiments, the composites have a series of flexible, elongated piezoelectric fibers arranged in a parallel array with adjacent fibers separated by relatively soft polymer. The piezoelectric fibers have a common poling direction transverse to their axial extension. The composite further includes flexible conductive material along the axial extension of the fibers for imposing or detecting an electric field.

Abstract: A laminated piezoelectric device and method for manufacturing the device, wherein a large number of thin sheets of piezoelectric ceramic are disposed one on another via electrode films formed on the surfaces of the sheets of piezoelectric ceramic. Electrode films of the piezoelectric elements then are connected to each other with electric conductors to form a one-piece laminated piezoelectric device. Polarization of the whole of a large number of piezoelectric elements then is performed at one time.

Abstract: An ultrasonic probe provided with an ultrasonic wave-transmitting/receiving element comprising a 1-3 type or 2-2 type composite piezoelectric body exposing a piezoelectric monocrystal from at least one of the faces of the composite piezoelectric body, and an electrode mounted on at least one of the faces of the composite piezoelectric body, wherein the composite piezoelectric body comprises a piezoelectric monocrystal whose electromechanical coupling coefficient ratio k.sub.33 /k.sub.t is 1.6 or more, and a resin whose acoustic impedance Zp is 4.times.10.sup.6 kg/m.sup.2 s or less.

Abstract: There is disclosed a device for applying vibrations to a cantilever used in an atomic force microscope. The cantilever has a base portion, and a probe is attached to the front end of the cantilever. The device has a piezoelectric plate subassembly consisting of first and second piezoelectric plates having junction faces cemented together. A piezoelectric plate subassembly support portion supports a part of the second piezoelectric plate. A voltage is applied to the piezoelectric plates so that one of them is stretched vertical to the junction faces and that the other is contracted vertical to the junction faces.

Abstract: A surface acoustic wave device has a main substrate; a comb-like electrode formed on one of the main surfaces of said main substrate; and a supplementary substrate joined with the other main surface of said main substrate, wherein said supplementary substrate has a smaller thermal expansion coefficient and a larger thickness than said main substrate.

Abstract: In a composite ultrasonic transducer, each of a plurality of piezoelectric ceramic columns included in a resin plate has a given circular cross-section and passes through the resin plate in a direction of a thickness of the resin plate, and central axes of the piezoelectric ceramic columns are regularly arranged at positions corresponding to nodes of a regular triangle network.

Abstract: A piezo-electric transformer comprising a piezo-electric body (PEB) including a driving region having input electrodes (1, 3) and at least one driven region having output electrodes (E11). These regions have opposite faces with at least one of the regions comprising a number of sections polarized in a direction perpendicular to the opposite faces and one pole of each section being connected to an opposite pole of another section by electrically conductive elements (2, 1', 2') in such a way that the sections form a series arrangement.These sections are in a very simple way effectively arranged in series, thereby increasing the input impedance of the piezo-electric transformer. Because the sections are polarized in opposing directions the electrically conductive elements can be of a very simple construction which do not require external conduction wires.

Abstract: A piezoelectric resonator has a substantially rectangular-parallelpiped-shaped base member. The base member includes a plurality of laminated piezoelectric layers. The piezoelectric layers are polarized in the longitudinal direction of the base member such that the direction of polarization differs at adjacent piezoelectric layers. At opposite major surfaces of the plurality of piezoelectric layers, internal electrodes are disposed. The internal electrodes have surface areas with different sizes and therefore, areas of pairs of opposing electrodes have different sizes. The internal electrodes are alternately covered by at least two insulating films provided on opposing side surfaces of the base member. The at least two insulating films cover different internal electrodes. External electrodes are disposed on the same or the opposing side surfaces of the base member and the external electrodes are connected to the internal electrodes.

Abstract: A piezoelectric resonator has a substantially rectangular-parallelpiped-shaped base member. The base member includes laminated piezoelectric layers which are polarized in the longitudinal direction of the base member such that the directions of polarization differ at adjacent piezoelectric layers. Internal electrodes are disposed between the piezoelectric layers. The internal electrodes each preferably comprise a plurality stripes dispose on main surfaces of the piezoelectric layers. On opposing side surfaces of the base member, the internal electrodes are alternately covered by at least two insulating films. The at least two insulating films cover different internal electrodes. External electrodes are disposed on the opposing side surfaces of the base member and are connected to internal electrodes.

Abstract: A piezoelectric resonator having excellent filter characteristics and effectively suppressing unnecessary ripples and/or spurious components includes first and second excitation electrodes disposed on a first major surface of a piezoelectric substrate, a first common electrode on a second major surface so as to oppose the first and second excitation electrodes with the substrate being located therebetween, and two lead lines extending along portions of longitudinal edges of the piezoelectric substrate. An excitation-lead line is connected to the first and second excitation electrodes which partly overlap a ground-terminal electrode provided on the lower surface with the piezoelectric substrate located therebetween.

Abstract: A piezoelectric resonator has a substantially rectangular-parallelpiped-shaped base member including a plurality of laminated piezoelectric layers. The piezoelectric layers have different dimensions in the longitudinal direction of the base member. The piezoelectric layers are polarized in the longitudinal direction of the base member such that the direction of polarization differs at every other piezoelectric layer. At both surfaces of the piezoelectric layers, a plurality of internal electrodes are disposed. The internal electrodes are alternately covered by at least two insulating films disposed on opposing side surfaces of the base member such that the at least two insulating films cover different electrodes. External electrodes are provided on the opposing side surfaces of the base member and the external electrodes are connected to internal electrodes.

Abstract: A piezoelectric ceramic transformer made from a piezoelectric ceramic material stacked in a multilayer package which has a driving section 502 formed by alternately stacking piezoelectric ceramic layers polarized in a direction of thickness of the piezoelectric plate. The driving section 502 has internal interdigitated electrode layers 504A, 504B for causing piezoelectric vibration by a driving voltage applied to an input terminal (Vin). A first driven section 506, also made from piezoelectric ceramic layers polarized in the longitudinal direction of the piezoelectric plate, for generating a first output voltage (Vout1) at a first output by the piezoelectric vibration transmitted from the driving section 502. A second driven section 510, made from piezoelectric ceramic layers polarized in the thickness direction of the piezoelectric plate, for generating a second output voltage (Vout2) at a second output by the piezoelectric vibration transmitted from the driving section 502.

Abstract: Composites for actuating or sensing deformation. In embodiments, the composites have a series of flexible, elongated piezoelectric fibers arranged in a parallel array with adjacent fibers separated by relatively soft polymer. The piezoelectric fibers have a common poling direction transverse to their axial extension. The composite further includes flexible conductive material along the axial extension of the fibers for imposing or detecting an electric field.

Abstract: There is provided a piezoelectric transformer including (a) a cylindrical body made of piezoelectric material and longitudinally defining a driven section and a voltage generating section, the voltage generating section being polarized in one of directions in a direction of a longitudinal axis of the cylindrical body, (b) a pair of first electrodes formed at a curved surface of the cylindrical body in the driven section and defining a plurality of regions in the driven section in a direction of a longitudinal axis of the cylindrical body, the first electrodes being electrically isolated with each other, the regions being polarized so that every other regions are polarized in opposite directions in a direction of a longitudinal axis of the cylindrical body, the pair of first electrodes comprising a plurality of strip-shaped electrodes wound around the cylindrical body and disposed in parallel with one another in a direction of a longitudinal axis of the cylindrical body, every other strip-shaped electrodes bei

Abstract: A method of preparing a pyroelectric mixture, especially for pyroelectric and piezoelectric components. At least two compounds are mixed in a prescribed ratio. One compound contains polymerizable and preferably achiral liquid-crystal monomers and the other a preferably achiral liquid-crystal polymer or copolymer. Each compound also contains hydrogen-bridging substituents. The mixture is heated to above its specific vitrification point. An electric field is applied to polymerize the monomer and polarize the mixture. The mixture is cooled to below its specific glass transition point with the field still present.

Abstract: An actuator incorporating the invention includes a body of a ferroelectric material. The material is single crystalline and incorporates solid solutions of lead zinc niobate-lead titanate or lead magnesium niobate-lead titanate, described by the formulae: Pb(Zn.sub.1/3 Nb.sub.2/3).sub.1-x Ti.sub.x O.sub.3 and Pb(Mg.sub.1/3 Nb.sub.2/3).sub.l-y Ti.sub.y O.sub.3 l where x and y are defined as 0.ltoreq.x<0.10, and 0.ltoreq.y<0.40. Electrodes enable application of an electric field across the body in a direction that is generally aligned with a <001> crystallographic axis of the ferroelectric material.

Abstract: This invention relates to novel oriented piezoelectric ceramic and ceramic/polymer composites. More particularly, it provides a novel piezoelectric composite design wherein the ceramic piezoelectric phase is oriented at an angle with respect to the direction of applied stress, thus giving improved electromechanical properties.

Abstract: A strain element which can realize shear distortion along the shearing direction includes a plurality of first electrodes provided on the surface of an electric-mechanical or mechanical-electrical energy conversion member, and second electrodes provided inside the conversion member. The combination of the electrodes used for polarization is different from that for driving or detection.

Abstract: Four piezoelectric elements are formed on both surfaces of a plate-shaped vibrating body. Two piezoelectric elements are formed to be opposite to each other at one side of the longitudinal center portion of the vibrating body. Another two piezoelectric elements are formed to be opposite to each other at the other side of the longitudinal center portion of the vibrating body. By applying a signal to the piezoelectric elements, the vibrating body is vibrated in a longitudinal direction. In this time, the vibrating body is vibrated in such a manner that longitudinal expansion and contraction take place simultaneously in a part of the vibrating body. By using such vibration, both longitudinal ends are not displaced in spite of the vibration of the vibrating body. The vibrating body can be used as an acceleration sensor by measuring the output voltages from the piezoelectric elements of the vibrating body.

Abstract: Methods and compositions are described for the preparation of piezoelectric ceramic-polymer composites having improved properties for application in piezoelectric devices. These composites consist of piezoelectric particles embedded in a polymer matrix. The improvements of this invention result from discoveries of the effects of particle size, particle size dispersity, volumetric loading levels, ceramic dielectric constant, and polymer dielectric constant on performance. Various improved devices based on these compositions are also described.

Abstract: Interleaved patterns of oppositely-poled regions are formed in a piezoelectric film by a technique in which an unpoled film is positioned between the pairs of an electromechanical apparatus with a pattern of like-poled electrodes movable into juxtaposition with the surfaces of the film which already includes on its surfaces the complementary (oppositely-poled) pattern of electrodes. In a second embodiment, a piezoelectric film is threaded about two drums with complimentary electrode patterns imbedded in the drum surfaces. The two patterns interleave with one another and are held at opposite potentials to impose the requisite poling pattern as a film wrapped about the drums moves in consecutive, but opposite directions. In a third embodiment, a piezoelectric film is positioned between two printed circuit boards which have complementary patterns of electrodes.

Abstract: A ladder type piezoelectric filter of the present invention is made usable in high frequency ranges by employing a piezoelectric resonator having the second harmonic wave mode SM. A series resonator and a parallel resonator of the ladder type piezoelectric filter of the present invention are so arranged that center electrode regions and outer electrode regions are mutually polarized along opposite directions, and the center electrode regions are connected to the outer electrode regions, respectively.

Abstract: A process for forming piezoelectric composites allows for novel composite designs, including composites with different polarizable material regions and composites with a gradient in volume fraction of polarizable material. Composites with fine-scale microstructures may be formed. The new forming method is an improvement to the traditional "dice and fill" technique currently being utilized to form piezoelectric composites.

Abstract: A wave-receiving piezoelectric device for use as, e.g., a hydrophone or a microphone, is constituted by a piezoelectric body having two surfaces sandwiching a thickness and including at least one surface provided with a recess (including a perforation communicating with the two surfaces) set in the thickness direction, and a rigid member having a contact surface and an outer surface opposite to the contact surface and disposed to cover said at least one surface with the contact surface so as to make the recess airtight. As a result, an acoustic pressure received by the outer surface is concentrated and applied onto said at least one surface of the piezoelectric body, thereby giving an improved wave-receiving sensitivity at an enhanced acoustic pressure.

Abstract: On a first piezoelectric sheet of a piezoelectric vibrator, a second piezoelectric sheet is stacked with interposition, between the sheets, of first-set electrodes, formed on an upper surface of the first piezoelectric sheet. Second-set electrodes are formed on an upper surface of the second piezoelectric sheet with each placed halfway between two adjacent ones of the first-set electrodes. The second piezoelectric sheet is poled in directions from each second-set electrode to the two adjacent ones of the first-set electrodes. Preferably, third-set electrodes are formed on a lower surface of the first piezoelectric sheet with each arranged halfway between two adjacent ones of the first-set electrodes. In this event, the first piezoelectric sheet is poled in directions from each third-set electrode to two adjacent ones of the first-set electrodes.

Abstract: In a piezoelectric resonator having a piezoelectric bar formed in a substantial rectangular parallelopiped and electrodes formed on a pair of confronting surfaces of the piezoelectric bar for resonating in the length expander mode, the piezoelectric bar has at least a bevel portion extending the longitudinal direction. In a ladder filter having series and parallel piezoelectric resonators, the series piezoelectric resonator has the bevel portion to shift a frequency of a spurious response to that of the parallel piezoelectric resonator to suppress the spurious response. It is disclosed that a second piezoelectric resonator has a piezoelectric bar formed in a rectangular parallelopiped has a length L, a width W, and a thickness T wherein L>W>T; and electrodes formed on a pair of confronting surfaces defined by L and T. Another ladder filter includes the second piezoelectric resonator as the series resonator to decrease a capacitance between the electrodes to increase an amount of attenuation.

Abstract: An ultrasonic device including a piezoelectric vibrator for converting an electric signal. The piezoelectric vibrator consists of a pillar-like piezoelectric ceramic and a pair of electrodes, A and B, positioned thereon on both end surfaces, ZA and ZB respectively, perpendicular to the polarization axis of the piezoelectric ceramic. The electrode A consists of at least two parts, namely electrodes A1 and A2, such that the electrodes A1 and A2 are not connected to each other. The electrode B consists of at least two parts, namely electrodes B1 and B2, such that the electrodes B1 and B2 are not connected to each other.

Abstract: A preferred embodiment of a resonator embodying the invention comprises entially a resonating plate, an action electrode and a detection electrode, and a supporting base. The electrodes are placed facing symmetrical narrow edges of the plate, opposite vibration loops, and are coupled to the plate by capacitive, electrostrictive or piezoelectric effect according to the material of which the plate is comprised. A very wide range of elastic solid materials can be used to embody the resonating plate. The plate is attached to the supporting base at points corresponding to vibration nodes of the plate. The plate vibrates advantageously according to a contour mode called Lame mode. High coefficients of quality in the region of 10.sup.7 are obtained. The resonators embodying the invention can be easily integrated. To do so, the plate is e.g. embodied in silicon. Such a resonator is included in a high-stability oscillating loop comprising a phase shifter and an amplifier.

Abstract: The invention relates to a piezoelectric element comprising a piezoelectric material 1, in the form of a polymer network, between at least two electrodes 2, 3. The piezoelectric material is formed from a starting material comprising a liquid crystalline monomeric material and a chiral compound. The starting material is brought to a temperature at which a smectic phase is formed, and an electric field is applied to obtain a dipolar orientation in the starting material, after which the polymer network is formed by means of photopolymerisation. The piezoelectric element thus manufactured can suitably be used for various electromechanical applications, as a sensor material, for pyroelectric applications and, in particular, also for optical applications.

Abstract: In a ladder-type piezoelectric filter having a series arm constituted by a plurality of series resonators connected in series and parallel arms respectively constituted by parallel resonators, each of the resonators being constructed using a piezoelectric plate, the direction of polarization of the piezoelectric plate of the series resonator arranged in at least one end of the series arm and the direction of polarization of the piezoelectric plate of the parallel resonator connected to the series resonator arranged in at least one end of the series arm are the same as seen from the side of a node of the series resonator arranged in the end and the parallel resonator connected to the series resonator.