Abstract: An ultrasonic probe is provided which includes a piezoelectric vibrator having an earth electrode and a signal electrode on a rear surface, an acoustic matching layer disposed on a front surface side of the piezoelectric vibrator, a packing material disposed on the rear surface of the piezoelectric vibrator, and a flexible printed circuit that is interposed between the piezoelectric vibrator and the packing material to cover the entire rear surface of the piezoelectric vibrator and has an earth wiring layer and a signal wiring layer. The earth wiring layer and the signal wiring layer are exposed from a surface facing the piezoelectric vibrator of the flexible printed circuit so as to be electrically connected to the earth electrode and the signal electrode through an exposed surface of the earth wiring layer and an exposed surface of the signal wiring layer, respectively.

Abstract: An ultrasound probe particularly for diagnostic purposes includes a first array of ultrasound transducers that generate ultrasound waves by electric excitation and transforming ultrasound waves impinging on them into electric signals. Each transducer is provided with contact electrodes which are connected respectively to a ground potential and to electric signals feeding lines. The first array of transducers includes emitting transducers and is intended only for generating and transmitting ultrasound waves, while a second array of transducers is provided over the first array of emitting transducer and includes receiving transducers for generating the electric receipt signals. The second array of transducers is formed of a material having piezoelectric behavior.

Abstract: An ultrasound transducer 10 comprises an application specific integrated circuit (ASIC) 14, an array of acoustic elements 20, and a pitch independent interposer 12. The ASIC 14 includes a plurality of contact pads 16 on a surface of the ASIC that are separated from adjacent ones thereof by a first pitch. The acoustic elements 22 of the array 20 are separated from adjacent ones thereof by a second pitch. In addition, the pitch independent interposer 12 features a plurality of conductive elements 26 separated from adjacent ones thereof by a third pitch different from both the first pitch and the second pitch.

Abstract: Provided are a piezoelectric acoustic transducer and a method of fabricating the same. In the piezoelectric acoustic transducer, a piezoelectric portion is formed in a portion of a diaphragm, and a deformation layer is formed in another portion of the diaphragm. Deformation of the piezoelectric portion is transferred to the deformation layer, or deformation of the deformation layer is transferred to the piezoelectric layer so that the deformation layer vibrates with the piezoelectric layer.

Abstract: The invention features methods for the manufacture of electrical components such as ultrasound transducers. In particular, the inventions provides methods of patterning electrodes, e.g., in the connection of an ultrasound transducer to an electrical circuit; methods of depositing metal on surfaces; and methods of making integrated matching layer for an ultrasound transducer. The invention also features ultrasound transducers produced by the methods described herein.

Abstract: An ultrasound transducer probe (40) includes a support substrate (54), an integrated circuit (42) and an array of piezoelectric elements (50). The support substrate (54) has a non-linear surface (55). The integrated circuit (42) physically couples to the support substrate (54) overlying the non-linear surface (55), wherein the integrated circuit (42) substantially conforms to a shape of the non-linear surface (55). An array of piezoelectric elements (50) couples to the integrated circuit (42).

Abstract: An ultrasonic transducer is configured to transmit or receive ultrasonic waves. The ultrasonic transducer includes a vibrating member and a piezoelectric member coupled to the vibrating member. The piezoelectric member includes a first piezoelectric part configured and arranged to be deformed by applied voltage to vibrate the vibrating member or configured and arranged to be deformed by vibration of the vibrating member to produce a potential difference, and a second piezoelectric part configured and arranged to be deformed by applied voltage to statically deflect the vibrating member.

Abstract: An ultrasonic transducer (104,313), transducer array (103) and an ultrasonic probe (100) are described.

Abstract: CMUT elements are formed on a substrate. Electrical conductors are formed to interconnect between different portions of the substrate. The substrate is then separated into pieces while maintaining the electrical connections across the separation. Since the conductors are flexible, the separated substrate slabs may be positioned on a curved surface while maintaining the electrical interconnection between the slabs. Large curvatures may be provided, such as associated with forming a multidimensional transducer array for use in a catheter. The electrical interconnections between the different slabs and elements may allow for a walking aperture arrangement for three dimensional imaging.

Abstract: A transducer array comprises a conductive back plate 32, a conductive front plate 33 having openings 62, and a plurality of piezoelectric vibrator elements 31 located in an array between the plates. The vibrator elements 31 are two-layer elements which each include a metal portion 311 and a PZT element 312. These elements 311, 312 are in electrical contact with the respective plates. The vibrator elements 31 are attached to support elements 51 upstanding as part of the back plate 32. The transducer array can be formed as a batch process in which the vibrator elements 31 are formed simultaneously, and then simultaneously attached to the support elements 51.

Abstract: An ultrasonic sensor includes a case having a substantially cylindrical shape with a bottom. The case has a piezoelectric element provided on the bottom, and a cushion member is engaged with a side portion of an opening of the case. A substrate and pin terminals are engaged in and held by a holding portion of the cushion member. On the substrate, electrodes that are connected to the pin terminals are provided. An opening portion is provided in a top surface of the cushion member. Lead wires that are electrically connected to the piezoelectric element extend out from the opening portion and are connected to the electrodes. The inside of the case is filled with an elastic resin from the opening portion.

Abstract: An ultrasound transducer manufactured by using a micromachining process comprises: a first electrode into which a control signal for transmitting ultrasound is input; a substrate on which the first electrode is formed; a second electrode that is a ground electrode facing the first electrode with a prescribed space between the first and second electrodes; a membrane on which the second electrode is formed and which vibrates and generates the ultrasound when a voltage is applied between the first and second electrodes; a piezoelectric film contacting the membrane; and a third electrode electrically continuous to the piezoelectric film.

Abstract: A speaker unit has a plurality of sound sources each outputting a sound wave. The compressional, sound wave output from the speaker unit arrives, or vibrates air, which moves a movable part of a three-axis acceleration sensor, or a microstructure of a chip to be tested TP. As the movable part thus moves, a value in resistance accordingly varies, and such variation is measured as based on an output voltage provided via a probe. A control unit determines a property of the three-axis acceleration sensor from a value in property as measured or measurement data. Furthermore, the plurality of sound sources can be spaced by a pitch of a predetermined value set as based on their difference in the distance to the movable part of the three-axis acceleration sensor and the wavelength of the test wave to apply a composite test wave to the movable part such that the composite sound wave's composite sound field is maximized.

Abstract: A capacitive micromachined ultrasonic transducer having an ultrasonic wave transmission/reception surface formed by arranging a plurality of transducer cells each of which includes a membrane having a first electrode and a supporting film for supporting the first electrode, and also includes a second electrode arranged being opposite to the first electrode and being spaced apart from the first electrode at a prescribed interval, wherein: the transducer cells are arranged on the basis of resonant frequencies of the transducer cells.

Abstract: When a film containing constituent elements of a target is formed on a substrate through a vapor deposition process using plasma with placing the substrate and the target to face each other, a potential in a spatial range of at least 10 mm extending laterally from the outer circumference of the substrate is controlled to be equal to a potential on the substrate, and/or the substrate is surrounded with a wall surface having a potential controlled to be equal to the potential on the substrate.

Abstract: A single chip transducer apparatus that includes on-chip electronic circuitry which, when connected properly to a two-dimensional matrix of ultrasonic transducer elements, provides enough information to an external imaging system to form three-dimensional images of the subject of interest. In a preferred embodiment, the circuitry provides an amplifier for each transducer element, and then conditions the output of the amplifier in several ways. In one embodiment of the invention, the elements' analog voltages are stored in a sample and hold circuit, and time multiplexed into a high speed line driver that sends many elements data down the interconnect to the system's high speed Analog to Digital converters. In another embodiment, the gain of the amplifiers can be controlled in time to provide aperture translation and time based expansion for translating and focusing image slices in the elevation direction.

Abstract: An acoustic wave sensing device integrated with micro-channels and a method for the same are described. The present invention uses a piezoelectric substrate with a thinner portion serving as a sensing area and formed via a micromaching or chemical process. An inter-digital transducer (IDT) is located on the thinner portion to produce flexural plate waves (FPW). The micro-channels can be formed together with the thinner portion via the same manufacturing process, or integrated into the piezoelectric substrate via linkage. In the present invention, a novel manufacturing process and design are proposed for fabrication of the acoustic wave sensing devices with a good piezoelectric characteristic, a stable temperature compensation property, and a robust structure. Thereby, the techniques of flexural plate waves can be applied for liquid sensors. In this way, the drawbacks of the conventional acoustic wave sensing devices, such as poor piezoelectric properties and fragile film structures, are removed.

Abstract: Method for ultrasound excitation of structures of any geometry, comprising the steps of producing a connection between a generator, an ultrasound converter, and at least one mechanical system to be excited, passing through a frequency range for determining an operating point, wherein at each approached frequency the power consumption of the system to be excited determines a current, and/or a voltage emitted by the generator, which is measured using a sensor such that a measurement value of the sensor renders the power output to the system to be excited, and performing an ultrasound excitation at the determined operating point, or around an environment around the operating point, wherein the operating point, once determined, or the environment around the operating point, once selected, is not modified anymore, and device for the ultrasound excitation of structures of any geometry by means of this method using a generator, an ultrasound converter, and at least one mechanical structure, wherein the generator has

Abstract: An ultrasonic sensor is disclosed. The ultrasonic sensor includes a plurality of sensor elements arranged in an array. Each sensor element includes an ultrasonic sensing element and an acoustic matching member. The ultrasonic sensor further includes a bonding member having a thickness approximately equal to a space interval between adjacent ultrasonic sensing elements. The bonding member adhesively fixes the plurality of sensor elements, and includes a portion contacting each ultrasonic sensing element. An elastic modulus of the portion is smaller than that of each ultrasonic sensing element.

Abstract: The present invention relates to a method for manufacturing a membrane or wall (3) of a material, which is capable of vapour/vacuum deposition, over an opening of an object (2). The method includes: placing the opening with a defined rim against a backing surface (4) coated with a layer (5) repellent to the depositable material; depositing of the depositable material on the object (2) and the backing surface (4) to form an element; separation of the element from the hacking surface (4) leaving a membrane (3) integral with the element. The invention also relates to such an object provided with a membrane (3), and particularly an ultrasonic transducer (11) provided with a front membrane (3).

Abstract: Piezoelectric transducers and associated methods are disclosed. In one embodiment, a piezoelectric transducer includes a support member, a piezoelectric element attached to the support member, and a pressurized chamber at one side of the piezoelectric element. The piezoelectric element comprises a flexible film, and the pressurized chamber contains a fluid that applies a static pressure to a side of the piezoelectric element.

Abstract: The present invention, in one set of embodiments, provides methods and systems for integrating conducting diamond electrodes into a high power acoustic resonator. More specifically, but not by way of limitation, in certain embodiments of the present invention, diamond electrodes may be integrated into a high power acoustic resonator to provide a robust sensing device that may provide for acoustic cleaning of the electrodes and increasing the rate of mass transport to the diamond electrodes. The diamond electrodes may be used as working, reference or counter electrodes or a combination of two or more of such electrodes. In certain aspects, the high power acoustic resonator may include an acoustic horn for focusing acoustic energy and the diamond electrodes may be coupled with the acoustic horn.

Abstract: Kits and methods for building devices for analyzing or suppressing vibrations in equipment are provided. An electrical-mechanical transducer is configured to be placed in operative contact with the equipment. The transducer may be directly mounted to a base plate that is configured for being mounted to the equipment. A first device (e.g., a printed circuit board) carrying electronic componentry is configured for transmitting vibration drive signals to the electrical-mechanical transducer. A second device (e.g., a printed circuit board) carrying electronic componentry is configured for receiving vibration sensing signals from the electrical-mechanical transducer. The first and second devices can be interchangeably mounted within a housing that can be mounted to the base plate. The housing may comprise an aperture for receiving the electrical-mechanical transducer.

Abstract: An ultrasonic flow rate measuring device for measuring the flow rate through a line through which a medium flows has at least one ultrasonic transducer that has a piezo element and a connecting element designed for attaching the ultrasonic transducer to the line with the piezo element attached to the connecting element. An intermediate layer including a plate is disposed between the piezo element and the connecting element that is electrically conductive and attachable to an electromagnetic shield. Thus, an ultrasonic flow rate measuring device that delivers a greater signal-to-noise ratio is achieved.

Abstract: An ultrasonic transducer in which lead wire connection is facilitated even when piezoelectric devices are divided in order to prevent lateral vibrations from affecting longitudinal vibrations is manufactured by a method comprising: a step in which first dicing grooves are formed on an acoustic matching layer and a piezoelectric device plate that are mounted together in order to form a plurality of piezoelectric devices; a step in which a board and the respective piezoelectric devices are connected together; a step in which surfaces in the vicinity of locations at which the board and the piezoelectric devices are connected together are coated with a conductive sheet; and a step in which the plurality of transducer elements are formed by forming second dicing grooves between the first dicing grooves formed on the piezoelectric devices and the board that is coated with the conductive sheet and on the acoustic matching layer.

Abstract: Unipolar, bipolar or sinusoidal transmitters may leave the transmitter in any of various states at the end of one pulse. Undesired acoustic energy may be generated to change states prior to beginning another transmit sequence or pulse. For example, phase inversion for tissue harmonic imaging is performed where two sequential pulses are transmitted with different phases. The first waveform starts at a low state and ends at the low state of a unipolar transmitter. The next waveform starts at the high state. Transmit apodization or spectrum control techniques may require a pattern of waveform starting states different than a current state. Acoustic disruption due to a change of state of the transmitter between transmissions for imaging is minimized.

Abstract: An ultrasonic sensor according to the present invention is used, for example, for detecting an obstacle positioned in front of an automotive vehicle. The ultrasonic sensor includes an piezoelectric element connected to an acoustic matching member and a processing circuit, all contained in a casing. Ultrasonic waves reflected on an object are received by the acoustic matching member and converted into electrical signals in the piezoelectric element. The electrical signals are processed in the processing circuit to thereby detect a distance to the object and/or positions of the object. A surface of the acoustic matching member connected to the piezoelectric element is made larger than the piezoelectric element to form an overhang area on a conductive layer formed on the acoustic matching member. In this manner, electrical connection in the ultrasonic sensor is easily made, and detection sensitivity of the ultrasonic sensor is enhanced.

Abstract: A composite structure of a backing material with enhanced conductivity for use in a transducer is presented. The composite structure includes a plurality of layers of backing material alternatingly arranged with a plurality of thermal conductive elements, wherein the plurality of thermal conductive elements are configured to transfer heat from a center of the transducer to a plurality of points on the composite structure of backing material.

Abstract: An electronic radial ultrasonic probe comprising an electronic radial array which comprises a plurality of ultrasonic transducers being continuously arrayed circularly around an insertion axis as center and also for which a transmission/reception of an ultrasonic wave is controlled by electronically selecting the plurality of ultrasonic transducer, comprises: a support member equipped on the electronic radial array; a lock member featured with a cavity in which the support member is inserted and with a lock groove for locking a balloon which is mounted in a manner to cover the electronic radial array and in which an ultrasonic medium is filled; and a filler member which is constituted by an adhesive material converting from a fluid state to a solid state, and is filled in the cavity.

Abstract: An electro-mechanical transducer, which provides dipole motion from its housing which is driven by a bender transducer attached to the housing at the outer edge and attached to an inertial mass at its center providing a lower resonance frequency, lower mechanical Q and enhanced motion and acoustical source level.

Abstract: An ultrasound imaging system (100). An exemplary system (100) includes a plurality of transducer elements (136) formed in subarrays (140) and a plurality of subarray circuit units (160?), with each circuit unit (160?) connected to a subarray (140) of the transducer elements (136). The circuitry in each unit (160?) comprises a plurality of integrated circuits (330, 340, 350), with at least a first (340) of the integrated circuits formed over a second (330) of the integrated circuits in a stacked configuration. In an example illustration the first integrated circuit (340) includes a first plurality of first bond pads (345) along a surface (342) thereof and the second integrated circuit (330) includes a second plurality of second bond pads (335) along a surface (331) thereof, with bond wires (344) extending between pairs of first and second bond pads to provide input/output signal connections therebetween.

Abstract: A single chip transducer apparatus that includes on-chip electronic circuitry which, when connected properly to a two-dimensional matrix of ultrasonic transducer elements, provides enough information to an external imaging system to form three-dimensional images of the subject of interest. In a preferred embodiment, the circuitry provides an amplifier for each transducer element, and then conditions the output of the amplifier in several ways. In one embodiment of the invention, the elements' analog voltages are stored in a sample and hold circuit, and time multiplexed into a high speed line driver that sends many elements data down the interconnect to the system's high speed Analog to Digital converters. In another embodiment, the gain of the amplifiers can be controlled in time to provide aperture translation and time based expansion for translating and focusing image slices in the elevation direction.

Abstract: A wideband and high sensitive ultrasonic probe adaptable to harmonic imaging by improving the sensitivity of vibrators in a wider frequency band without hindering the operation of piezoelectric materials. The ultrasonic probe includes: a vibrator array including plural vibrators for transmitting and/or receiving ultrasonic waves, each of the plural vibrators including plural piezoelectric materials arranged in parallel between a first electrode and a second electrode and having different frequency constants from one another; at least one acoustic matching layer provided on a first surface of the vibrator array; and a backing material provided on a second surface opposite to the first surface of the vibrator array.

Abstract: A focused ultrasound system includes a transducer array, a controller for providing drive signals to the transducer array, and a switch. The transducer array includes a plurality of “n” transducer elements, and the controller includes a plurality of “m” output channels providing sets of drive signals having respective phase shift values, “m” being less than “n.” The switch is coupled to the output channels of the controller and to the transducer elements, and is configured for connecting the output channels to respective transducer elements. The controller may assign the transducer elements to respective output channels based upon a size and/or shape of a desired focal zone within the target region, to steer or otherwise move a location of the focal zone, and/or to compensate for tissue aberrations caused by tissue between the transducer array and the focal zone, geometric tolerances and/or impedance variations of the transducer elements.

Abstract: An acoustic pulse array is described. The pulse array can include a plane wave pulse generator having a first side from which a first wave emanates, and a second side from which a second wave emanates. A first waveguide array can be attached to the generator on the first side of the generator, and a second waveguide array can be attached to a second side of the generator. One or more of the waveguides can be attached to the generator so as to orient the waveguide to transmit wave pulses in a direction that is substantially perpendicular to the generator.

Abstract: Reflective and slanted array channelized sensor arrays having a broadband source providing acoustic energy to a reflective or slanted array that reflects a portion of the incident signal to one or more sensing films wherein the response is measured.

Abstract: The present invention relates to a process for producing a block of low-frequency piezoelectric composite material having rows of superposed ceramic posts embedded in a dielectric. This process includes the production of the block of composite material from two superposed identical half-blocks, produced by cutting into a single pre-machined piezoelectric ceramic block. According to the invention, the block of ceramic material thus constituted is then machined so as to form a structure comprising rows of aligned posts, each post being formed from two elementary posts facing each other in strict alignment. The ceramic structure thus produced is then integrated into an appropriate dielectric matrix. The block thus produced is intended to be used for manufacturing acoustic transducers from composite materials. The invention relates in particular to the field of sonar detectors designed to detect objects located at a relatively short distance from the detector.

Abstract: In an ultrasonic transducer including a gap between an upper electrode and a lower electrode on a silicon substrate, it is made possible to reduce or adjust warpage of an above-gap membrane vibrated by electrostatic actuation due to internal stress. A fourth insulating film and a fifth insulating film of films positioned above the gap which is a cavity required for transmitting and receiving ultrasonic are respectively a silicon oxide film for compression stress and a silicon nitride film for tensile stress. Therefore, compression stress and tensile stress cancel each other, so that warpage of the above-gap membrane is reduced. An amount of warpage can be adjusted by adjusting a film thickness of the fourth insulating film and a film thickness of the fifth insulating film.

Abstract: An acousto-optic modulator includes an acousto-optic bulk medium. A transducer is attached to the acousto-optic bulk medium and formed as a linear array of electrodes. A transducer driver is connected to each electrode and comprises a plurality of amplifiers connected to the electrodes such that each electrode is driven by a respective amplifier as a means to provide a low cost alternative to the use of higher power hybrid amplifiers in conventional AO device applications.

Abstract: An improved process of substrate cleaving and a device to perform the cleaving are disclosed. In the traditional cleaving process, a layer of microbubbles is created within a substrate through the implantation of ions of a gaseous species, such as hydrogen or helium. The size and spatial distribution of these microbubbles is enhanced through the use of ultrasound energy. The ultrasound energy causes smaller microbubbles to join together and also reduces the straggle. An ultrasonic transducer is acoustically linked with the substrate to facilitate these effects. In some embodiments, the ultrasonic transducer is in communication with the platen, such that ultrasound energy can be applied during ion implantation and/or immediately thereafter. In other embodiments, the ultrasonic energy is applied to the substrate during a subsequent process, such as an anneal.

Abstract: Piezoelectric actuator (51) includes a piezoelectric element (11) that performs expansion/contraction movement in accordance with the state of an electrical field, a base (21) with the piezoelectric element (11) adhered to one surface thereof, and a support member (46) for supporting the piezoelectric element (11) and the base (21), the piezoelectric element (11) and base (21) vibrating up and down in accordance with the expansion/contraction movement of the piezoelectric element (11). The base (21) is connected to the support member (46) by way of a vibration film (31) having less rigidity than the base (21). In addition, the piezoelectric element (11) and support member (46) have different outline shapes.

Abstract: An ultrasound transducer comprises a multiplicity of piezoelectric transducer elements attached to a backing layer and forming a two-dimensional array, the transducer elements each comprising one or more piezoelectric members that collectively form an energy transmitting surface of the respective transducer element, the energy transmitting surface having a geometric center, wherein the respective transducer element geometric centers are in an irregular formation.

Abstract: A physical shield placed on the face of a high intensity focused ultrasound transducer for medical applications is described. The shield may be shaped or angled to match a particular pattern of mechanical or acoustic energy that may damage the transducer during operation. The shield may be ablative, replaceable or modified as needed. Methods of manufacturing a transducer with a shield are also disclosed.

Abstract: Described herein are compliant electroactive polymer transducers for use in acoustic applications. A compliant electroactive polymer transducer includes a compliant electroactive polymer at least two electrodes. For sound production, circuitry in electrical communication with the transducer electrodes is configured to apply a driving signal that causes the electroactive polymer to deflect in the acoustic range.

Abstract: An ultrasonic probe according to the present invention includes: an ultrasonic element for transmitting and receiving an ultrasonic signal; a signal line for transmitting an electric signal to or from the ultrasonic element; and a ground line for supplying a ground potential to the ultrasonic element. The ultrasonic element is connected electrically with a sensor signal substrate and a sensor ground substrate. These substrates are connected electrically with the signal line and the ground line, respectively, via a cable substrate. The sensor ground substrate and the cable substrate are connected directly or via a relay ground substrate.

Abstract: A method of manufacturing a perovskite-type oxide single crystal having a desired composition and exhibiting excellent properties. The method includes the steps of: (a) forming a precursor of a perovskite-type oxide, at least a part of which is in an amorphous state, on a seed single crystal substrate to prepare a complex of the seed single crystal and the precursor, and (b) heat-treating the complex to induce solid phase epitaxy in the precursor, and thereby, forming a single crystal of the perovskite-type oxide.

Abstract: An ultrasonic transducer includes a piezoelectric resonator including a pair of electrodes sandwiching a piezoelectric body and provided with the backing layer in contact with one of the electrodes of the piezoelectric resonator and having the same acoustic characteristic impedance as the piezoelectric body. A method includes the step of driving the ultrasonic transducer so as to satisfy a condition: 2Th?Td?6Th where Th is a propagation time of an ultrasonic wave in the piezoelectric body sandwiched by the pair of electrodes, and Td is a pulse width of a drive pulse driving the piezoelectric resonator.

Abstract: A piezoelectric resonator and a piezoelectric thin-film filter including the piezoelectric resonator. The piezoelectric resonator includes a piezoelectric layer disposed between a pair of conductive layers to form a vibrating region. Outer edges of the vibrating region each have a waveform. The vibrating region includes a peripheral portion extending along the outer edges of the planar shape and having a relatively small thickness; and a central portion extending inside the peripheral portion and having a relatively large thickness. The piezoelectric resonator is thus capable of suppressing long-wavelength spurious modes and short-wavelength spurious modes.

Abstract: Ulstrasound typically in the range 15 KHz to 1 MHz and at a power of about 100 watts over a zone of a few sq. cm is applied via a horn shaped cavity of a transmitter for processing a fluid medium, for example for processing a body of liquid having a foaming surface layer whereby the foaming can be quelled rapidly.

Abstract: A case member of an ultrasonic sensor includes an outer case member having a substantially cylindrical shape with a bottom surface and an inner case member. Cutout portions having a predetermined size are arranged so as to face each other in a lower portion of a sidewall of the inner case member. The inner case member is made of a metal material having a density that is greater than that of the outer case member. Consequently, an elliptical vibrating-surface amplitude profile can be formed in a vibrating surface of the ultrasonic sensor, and an ultrasonic sensor having stable anisotropy in directional properties can be provided. Further, the ultrasonic sensor has a small amount of displacement of side vibration.