Abstract: The invention relates to a wave-emitting device comprising an electromechanical actuator stimulated by a signal generator that allows it to generate torsional waves with a higher amplitude, and to an ultrasonic transducer comprising said device. The use of said devices allows the reconstruction of the structural characteristics of the materials subject to the waves generated by the emitter device.

Abstract: The disclosed embodiments include quadrupole transmitters and methods to determine wave velocities of a downhole formation. In some embodiments, the quadrupole transmitter has a first piezoelectric ring and a second piezoelectric ring that alternatively contracts and expands in opposite radial directions relative to the first piezoelectric ring in response to being simultaneously excited with the first piezoelectric ring. The quadrupole transmitter also includes a covering sleeve surrounding exterior surfaces of the two piezoelectric rings. The quadrupole transmitter further includes a windowed sleeve surrounding the two piezoelectric rings and having a first portion and a second portion adjacent to the first portion. The first portion and the second portion are formed from multiple window sections and adjacent covered sections that are positioned around different sections of the piezoelectric rings to allow transmission of quadrupole acoustic signals when the piezoelectric rings are simultaneously excited.

Abstract: Disclosed is a broadband underwater acoustic transceiver device. The device can be used in particular for positioning, detection, range finding or underwater acoustic communication. The device coaxially combines, within a transceiver device, a Tonpilz transducer and a FFR transducer, the FFR being arranged in front of the transmission face/horn of the Tonpilz transducer. In such a configuration, the Tonpilz horn also acts as reflective tape for the FFR transducer, forming a common tape-horn element. Furthermore, an annular baffle surrounding the Tonpilz pillar creates a Helmholtz cavity for broadening the emission band towards the low frequencies.

Abstract: Some embodiments are directed to a piezoelectric sensor, including a body with a central cavity; and a membrane extending over the cavity, which membrane is fastened to the body via its periphery and includes a carrier layer made of polymer and a sensitive layer made of piezoelectric polymer, the membrane being able to deform or vibrate. The sensitive layer is made of a material including a polymer filled with inorganic nanomaterials. Instrument including such a sensor.

Abstract: An acoustic vector sensor (“AVS”) includes one or more sensitive elements arranged in an orthogonal configuration to provide high-sensitivity directional performance. The one more sensitive elements may be seismometers arranged in a pendulum-type configuration. The AVS further includes a hydrophone.

Abstract: A downhole acoustic emitter including a support housing with a cavity and ports, in which housing are disposed a rod-type magnetostrictive transducer with an electrical coil on the rods, and an acoustic waveguide in the form of a cylinder which transitions into a tapering cone. The cylindrical portion of the acoustic waveguide is disposed inside the support housing, and the conical portion is disposed outside the housing. The upper end surface of the acoustic waveguide is coaxially joined to the lower emitting surface of the magnetostrictive transducer by soldering, and the acoustic waveguide is joined at its middle portion, which coincides with the zero vibration point of the waveguide, to the support housing by a threaded joint. The downhole acoustic emitter is provided with an emitting element, the upper end of which is coaxially joined to the lower end of the acoustic waveguide by a threaded joint.

Abstract: A bender bar transducer having stacked encapsulated actuators provides improved acoustic power over a wider frequency range, low applied voltage requirements and consistent part-to-part performance.

Abstract: Embodiments of the present invention are directed to a method of stimulating a cornea. A non-limiting example of the method includes capturing a sound with a microphone. A non-limiting example of the method also includes transducing the sound to an electric signal by a microprocessor. A non-limiting example of the method also includes stimulating a piezo-electric element adjacent to a receptor of the cornea, wherein the piezo-electric element is positioned on an eye lens with an electric signal. A non-limiting example of the method also includes mechanically stimulating a receptor of the cornea with the stimulated piezo-electric element.

Abstract: A system and a method for measuring a speed of sound in a liquid contained in a vessel or in a gaseous medium contained in the same vessel above the surface of the liquid. The method comprises: transmitting a first acoustic signal into the vessel to travel inside a first travelling plane. Emitting a second acoustic signal into the wall of the vessel to travel inside the wall of the vessel along a perimeter of the first travelling plane until it is received and obtaining a first time of flight of the first acoustic signal and a second time of flight of the second acoustic signal and obtaining a speed of sound in the vessel wall from a data memory. Determining the speed of sound in the liquid or in the gaseous medium from the length of the travelling path of the first acoustic signal and from the first time of flight.

Abstract: A vibration device includes a support body that includes first and second principal surfaces and a through hole penetrating through the support body to open at the first and second principal surfaces, a first vibration element on the side of the first principal surface of the support body, and a second vibration element on the side of the second principal surface of the support body. The first vibration element includes a first vibration body that is translucent. The second vibration element includes a second vibration body and a second piezoelectric vibrator provided on the second vibration body.

Abstract: An in-well type acoustic telemetry system includes an elongate tubular housing, an elongate transmitter in the tubular housing, a receiver in the tubular housing, and a spring between the transmitter and the housing biasing the transmitter into acoustic coupling to the housing. The transmitter is adapted to generate an output acoustic signal by linearly fluctuating in response to an electrical signal. The receiver is adapted to generate another electrical signal by linearly fluctuating in response to an input acoustic signal.

Abstract: A hydrophone is provided which includes at least four piezoelectric sensors mounted to a central section of syntactic acoustic dampening material as well as a layer of corprene between the piezoelectric sensors and the central section. Each of the piezoelectric sensors includes radially poled piezoelectric cylinders wired in series with inert polycarbonate endcaps and an isolator layer. The piezoelectric cylinders are assembled co-axially. The piezoelectric cylinders are then adhered to the central section and sandwich a layer of corprene. The corprene also adds noise dampening properties.

Abstract: A pressure-sensing device including a pressed component that has a contact surface to which pressure is applied by contact from a presser; a polymeric piezoelectric element that is disposed at an opposite side from the contact surface of the pressed component and that has a piezoelectric constant d14 of 1 pC/N or more as measured at 25° C. using a stress-charge method; a curable resin layer that includes at least one selected from the group consisting of cold-setting resins, thermosetting resins, and actinic radiation-curable resins and that is in contact with at least part of a surface of the polymeric piezoelectric element; and an electrode that is in contact with at least part of a surface of the polymeric piezoelectric element or of a surface of the curable resin layer.

Abstract: A system for producing sound waves in a medium, the system comprising: at least two first free-flooded ring transducers centered about a first axis, the first free-flooded ring transducers being substantially cylindrical and having an axial gap of height g therebetween such that they form a first column; and at least one cylindrical body centered about the first axis nested in the first column, such that the cylindrical body is aligned with the axial gap. The cylindrical body may be a tweeter free-flooded ring transducer. This provides for improved wideband performance in a free flooded ring array.

Abstract: A digital video camera is disclosed comprising a substantially cylindrical camera body defining a longitudinal axis, and first and second user inputs arranged on a wall of the camera body, wherein one of the first and second user inputs is arranged on a side wall of the camera body in a plane that is generally parallel to the longitudinal axis, and the other of the first and second user inputs is arranged on an end wall of the camera body in a plane that is generally orthogonal to the longitudinal axis, one of the first and second user inputs being actuable to start recording and the other of the first and second user inputs being actuable to stop recording.

Abstract: A shielded electronic array is provided and includes a main plate having opposing first and second major surfaces, first and second electronic devices disposed on respective first portions of the first and second major surfaces, respectively, a noise-shielding plate disposed on a second portion of the second major surface, an insulated eyelet, which is press-fittable into the main and noise-shielding plates and first and second wiring components. The first wiring component extends along a main plate plane from the second electronic device. The second wiring component extends from the first wiring component to the first electronic device and has an exposed first portion and a second portion extending through the insulated eyelet.

Abstract: An ultrasonic transducer device is disclosed. The device includes a body and an ultrasonic transducer mounted onto the body. The ultrasonic transducer comprises a shoulder and an O-ring placed on the shoulder. The O-ring substantially covers the interface between the ultrasonic transducer and the body.

Abstract: A variable frontal area craft for performing drift measurements. The craft includes a variable frontal area mechanism and a propulsion assembly, and is configured to operate at least partially submerged in a liquid. The variable frontal area mechanism is configured to operate in a first, high frontal area state and in a second, low frontal area state.

Abstract: An implantable medical device that includes an elongated lead body having an outer surface and a first opening along the outer surface, a first sensor positioned along the lead body and configured to receive first acoustic signals through the first opening of the lead body and generate an electrical signal representative of sounds produced at a first targeted location along a patient's cardiovascular system, and a processor configured to determine an intensity of the first acoustic signals, and determine changes in blood pressure in response to the determined intensity.

Abstract: A system for observing a swimming activity of a person includes a waterproof housing (BET) having a motion sensor (MS), and is furnished with fixing means (BEL) for securely fastening the housing (BET) to a part of the body of a user. The system has analysis means (AN) for analyzing the signals transmitted by the motion sensor (MS) to at least one measurement axis and which are adapted for determining the type of swimming of the user as a function of time by using a hidden Markov model with N states corresponding respectively to N types of swimming.

Abstract: An apparatus for interrogating a subsurface material includes a carrier configured to be conveyed through a borehole penetrating the earth, an array of acoustic transducers disposed on the carrier and configured to be compensated for ambient pressure in the borehole, and electronics coupled to the array and configured to operate the array to interrogate the subsurface material. Each acoustic transducer in the array includes a substrate, a bottom electrode disposed on the substrate, a top electrode disposed above the bottom electrode, an insulation layer disposed between the bottom electrode and the top electrode and defining a cavity into which the top electrode may deflect, and a pressure compensating fluid disposed in the cavity and in pressure communication with ambient pressure of the array.

Abstract: Provided is a piezoelectric stack transducer. In a transducer portion, a plurality of piezoelectric transducers which output maximum amplitude at different frequencies are continuously stacked. A stacked electrode portion is provided on both surfaces of each of the plurality of continuously stacked piezoelectric transducers and supplies an electric signal so that vibration is generated. In this case, the plurality of piezoelectric transducers have different diameters. According to the present invention, it is possible to implement a piezoelectric stack transducer which exhibits constant amplitude (output) at different frequencies by piezoelectric transducers exhibiting different amplitudes at respective frequencies according to natural frequencies supplementing amplitude of a different piezoelectric transducer.

Abstract: An ultrasonic processing apparatus is disclosed that supports an ultrasonic rod transducer without restricting the transmission of ultrasonic vibrations from the rod transducer to liquid in a processing tank. A support structure supports one or both converter heads of the rod transducer without restricting its vibration.

Abstract: A transducer assembly for transmitting broadband sonar beams and receiving broadband sonar returned echoes with a low-cost transducer element mounted into a low-cost acoustic structure. By using a transducer element which is sufficiently thin, broadband can be achieved at a significant cost savings over existing methods and devices. Since the transducer element is sufficiently thin, a large portion of the signal energy is coupled transversely into the acoustic structure, resulting in a heavy acoustic load on the transducer element which in turn results in broadband operation. Broadband operation may be enhanced by at least partially enclosing the sufficiently thin transducer element within an aperture and/or a cap.

Abstract: The ultrasonic probe comprises an ultrasonic transducer section in which a plural of ultrasonic transducers arranged in a row in the scanning direction, an acoustic lens and a low attenuation medium, and further comprises a probe shell housing the ultrasonic transducer section, acoustic lens, and low attenuation medium. In the probe shell, the low attenuation medium is located at the top end (contact surface with a subject to be examined) of the ultrasonic probe, and the low attenuation medium, acoustic lens, and ultrasonic transducer section are located in order. In this way, the ultrasonic waves transmitted from the ultrasonic transducer section are converged by the acoustic lens and transmitted outside the probe shell through the low attenuation medium. The reflection waves from the subject to be examined are received by the ultrasonic transducer section through the low attenuation medium.

Abstract: A universal air bubble detector allows for use with a variety of sizes and types of tubing. The detector maintains proper alignment of a sensor emitter and receiver with different sizes of tubing. The detector may be mounted on existing equipment or may be used to monitor a tubing at any position along the tubing, and may operate in a stand alone mode or in combination with existing equipment.

Abstract: A method of forming an electrical component is provided. The method comprises preparing a subassembly by electrically connecting an integrated circuit to a flexible circuit; and attaching the subassembly to a multilayer ceramic capacitor having a mounting surface with a curvature deviation exceeding 0.008 inches per inch.

Abstract: The invention may be embodied as an ultrasonic plane wave generator having a first sheet of piezoelectric material and a second sheet of piezoelectric material. A shared electrode may be between the first sheet and the second sheet. A first electrode set may have a plurality of electrodes, and these electrodes may be positioned with respect to the first sheet to form a set of wave generators. A wave generator in this first wave generator set may include the shared electrode, the first sheet, and one of the electrodes in the first electrode set. A second electrode set may have a plurality of electrodes, and these electrodes may be positioned with respect to the second sheet to form another set of wave generators. A wave generator in this second wave generator set may include the shared electrode, the second sheet, and one of the electrodes in the second electrode set.

Abstract: A transducer assembly for transmitting broadband sonar beams and receiving broadband sonar returned echoes with a low-cost transducer element mounted into a low-cost acoustic structure. By using a transducer element which is sufficiently thin, broadband can be achieved at a significant cost savings over existing methods and devices. Since the transducer element is sufficiently thin, a large portion of the signal energy is coupled transversely into the acoustic structure, resulting in a heavy acoustic load on the transducer element which in turn results in broadband operation. Broadband operation may be enhanced by at least partially enclosing the sufficiently thin transducer element within an aperture and/or a cap.

Abstract: A pressure-compensated transducer assembly has an inner housing with a closed transducer end and an outer housing with an open transducer end. A piezoelectric assembly is in the closed transducer end of the inner housing. A liquid-filled inter-housing space is between the outer housing and the inner housing, and has a transducer end open to the environment and a connection end open to the piezo assembly space. A blocking member separates the transducer end of the inter-housing space from the connection end, and prevents fluids from flowing between the two ends. The blocking member is movable within the inter-housing space in response to pressure differences the environment and the interior space.

Abstract: A transducer for sub-ocean bottom imaging includes: a housing capable of withstanding hydrostatic pressure of about 9,000 pounds per square inch; a transmitting layer positioned within the housing to transmit two primary high frequency transmit beams that generate a low frequency signal whose frequency is an arithmetic difference between the two primary beams for high resolution sub-ocean bottom imaging while maintaining high spatial resolution or directivity; and a receiving layer collocated with the transmitting layer within the housing that is mechanically tuned to resonate at the difference frequency producing high receive sensitivity.

Abstract: An acoustic transducer includes a ring oscillator. The ring oscillator includes: a first cushioning material; a pair of first and second annular members that are laminated in an axial direction thereof with the first cushioning material therebetween, each of the annular members having first and second ends in a circumferential direction thereof, and a notch portion formed between the first and second end; a first connecting portion that connects the first end of the first annular member and the second end of the second annular member; and a second connecting portion that connects the second end of the first annular member and the first end of the second annular member.

Abstract: A piezoelectric sensing device is described for measuring material thickness of targets such as pipes, tubes, and other conduits that carry fluids. The piezoelectric sensing device includes a piezoelectric element mounted to a flexible circuit with glass reinforced polyimide C-stage cover layers surrounding a pure polyimide C-stage core.

Abstract: An ultrasound transducer includes an array of PZT elements mounted on a non-recessed distal surface of a backing block. Between each element and the backing block is a conductive region formed as a portion of a metallic layer sputtered onto the distal surface. Traces on a longitudinally extending circuit board—preferably, a substantially rigid printed circuit board, which may be embedded within the block—connect the conductive region, and thus the PZT element, with any conventional external ultrasound imaging system. A substantially “T” or “inverted-L” shaped electrode is thereby formed for each element, with no need for soldering. At least one longitudinally extending metallic member mounted on a respective lateral surface of the backing block forms a heat sink and a common electrical ground. A thermally and electrically conductive layer, such as of foil, transfers heat from at least one matching layer mounted on the elements to the metallic member.

Abstract: A sound sensor, a hydrophone including the sound sensor, and a pressure balancing device for using for the hydrophone are provided. The hydrophone includes: a sensor including a sensing part and a pressure balancing part; a printed circuit board (PCB) that is electrically connected to the sensor; a case that houses the sensor and the PCB and that has an opening at one side thereof; an elastic membrane that covers the opening of the case; and a signal line that is electrically connected to the PCB to be extended to the outside of the case. The pressure balancing part includes a diaphragm of a thin film and a support that supports the diaphragm. A pressure balancing hole is formed at one side of the pressure balancing part, and at the inside of the pressure balancing part, a channel that is connected to the pressure balancing hole is formed, and a compressible gas is filled in the channel.

Abstract: In the ultrasound transducer of the present embodiment, front surface electrodes and rear surface electrodes are provided for a plurality of ultrasound vibrators. A circuit board is disposed on the rear surface side of the ultrasound vibrators, and connected to the rear surface electrodes. An electronic circuit is connected to the surface opposite to that of the rear surface electrodes side on the circuit board, and has signal paths to each ultrasound vibrator through the circuit board. A backing material is disposed on the rear surface side of the ultrasound vibrators, and is provided so as to sandwich between it and the ultrasound vibrators the circuit board and the electronic circuit.

Abstract: A system having improved trapping force for acoustophoresis is described where the trapping force is improved by manipulation of the frequency of the ultrasonic transducer. The transducer includes a ceramic crystal. The crystal may be directly exposed to fluid flow. The crystal may be air backed, resulting in a higher Q factor.

Abstract: A hydrophone for recording underwater sound includes a housing having an outer surface designed to serve as a boundary surface for an incident sound wave and at least one vibration sensor having a sensor surface for recording sound waves and for preparing a sensor signal. The sensor surface of the vibration sensor is in an opening of the housing. A hydrophone assembly includes a plurality of the hydrophones.

Abstract: The present invention provides a method of packaging surface microfabricated transducers such that electrical connections, protection, and relevant environmental exposure are realized prior to their separation into discrete components. The packaging method also isolates elements of array transducers. Post processing of wafers consisting of transducers only on the top few microns of the wafer surface can be used to create a wafer scale packaging solution. By spinning or otherwise depositing polymeric and metallic thin and thick films, and by lithographically defining apertures and patterns on such films, transducers can be fully packaged prior to the final dicing steps that would separate the packaged transducers from each other. In the case of microfabricated ultrasonic transducers, such packaging layers can also enable flexible transducers and eliminate or curtail the acoustic cross-coupling that can occur between array elements.

Abstract: A system and method for determining optimal values for the geometrical features of an ultrasonic transducer having one or more elements, the method including backprojection ray-tracing to determine the parameters required for apertures located on an ultrasonic probe surface. The ultrasonic probe design system includes an interface for inputting statement parameters, insonification requirements, and geometric constraints, with an engine responsive to the interface and configured to determine and provide an optimized transducer geometric design output.

Abstract: An apparatus comprises a first transducer support configured to receive a first transducer in a first opening. A face of the first face of the transducer is located in a first plane. The apparatus also comprises a second transducer support configured to receive a second transducer in a second opening. A face of the second transducer is located in a second plane substantially parallel to the first plane.

Abstract: A control system for an underwater camera housing, including a pin assembly within the housing wall. The pin has a clamp ring and a set of O-rings at an end of the pin. The pin is received into a well in the housing. A spring is received into a bushing also positioned within the well, with the pin inserted into the center of the spring, and the spring compressed against the seat of the bushing by the clamp ring. The pin is depress-able to contact a control button of the housed camera. The control system additionally includes a knob rotatably attached to the housing's exterior. The knob has a boss magnet to move a worker magnet positioned on the housing's interior. The knob is rotatable to move the boss magnet, and so move the worker magnet, to control functions of the housed camera.

Abstract: An acoustic transducer includes a ring oscillator. The ring oscillator includes: a first cushioning material; a pair of first and second annular members that are laminated in an axial direction thereof with the first cushioning material therebetween, each of the annular members having first and second ends in a circumferential direction thereof, and a notch portion formed between the first and second end; a first connecting portion that connects the first end of the first annular member and the second end of the second annular member; and a second connecting portion that connects the second end of the first annular member and the first end of the second annular member.

Abstract: Sensors used in mapping strata beneath a marine body are described, such as in a towed array. A first acoustic sensor uses a piezoelectric sensor mounted with a thin film separation layer of flexible microspheres on a rigid substrate. Additional non-acoustic sensors are optionally mounted on the rigid substrate for generation of output used to reduce noise observed by the acoustic sensors. A second sensor is a motion sensor including a conductive liquid in a chamber between a rigid tube and a piezoelectric motion film circumferentially wrapped about the tube. Combinations of acoustic, non-acoustic, and motion sensors co-located in rigid streamer housing sections are provided, which reduce noise associated with different sensor locations.

Abstract: Sensors used in mapping strata beneath a marine body are described, such as in a flexible neutrally buoyant towed array. A first sensor is a motion sensor including a conductive liquid in a chamber between a rigid tube and a piezoelectric motion film circumferentially wrapped about the tube. The liquid transfer signal from a gravitational bottom of the sensor while rejecting water body surface reflected noise. A second sensor is a traditional acoustic sensor or a novel acoustic sensor using a piezoelectric sensor mounted with a thin film separation layer of flexible microspheres on a rigid substrate. Combinations of motion sensors and acoustic sensors co-located in a rigid streamer housing sections are provided.

Abstract: A transducer with a closed heat pipe is provided with a hot surface and a cold surface. The hot surface is in contact with the transducer interior and the cold surface is in contact with a cooler contact area. A fluid is used in the pipe which boils at the temperature of the hot surface and condenses at the temperature of the cold surface. A wick inside the heat pipe facilities the return by capillary action of the condensed fluid to the hot end. The heat pipe can be evacuated to adjust the boiling temperature of the fluid. A variant involves drilling additional holes into ceramic rings and inserting heat pipes. Increasing the heat pipe length into the tail mass and the piston increases the cool region for the fluid to condense; thereby improving the performance of the transducer.

Abstract: An ultrasonic transducer for use in a fluid medium includes at least one piezoelectric transducer element, at least one matching body for the promotion of a vibrational coupling between the piezoelectric transducer element and the fluid medium, and at least one compensating body situated between the piezoelectric transducer element and the matching body for the reduction of thermal stresses, the compensating body having a coefficient of thermal expansion that is between a coefficient of thermal expansion of the piezoelectric transducer element and a coefficient of thermal expansion of the matching body.

Abstract: An ultrasonic transducer is described for use in a fluid medium. The ultrasonic transducer includes at least one piezoelectric transducer element and at least one matching element for promoting an oscillation injection between the piezoelectric transducer element and the fluid medium. The ultrasonic transducer also includes a housing (112), the piezoelectric transducer element being inserted in the housing. The housing has at least one opening facing the fluid medium, the matching element being inserted at least partially into the opening. The ultrasonic transducer also has at least one sealing element, which seals at least one intervening space between the matching element and the housing in such a way that an inner space of the housing is at least largely sealed from the fluid medium.

Abstract: The invention utilizes single and multiple frequency ultrasound generators driving single and multiple frequency resonant and harmonic transducer arrays at frequencies into the megasonic range. Generator signals that increase cavitation efficiency improve the performance of the cleaning, microbiological inactivation, sonochemistry or processing systems.

Abstract: A piezoelectric composite micromachined ultrasound transducer including single and multilayer 1-D and 2-D arrays having through-wafer-vias (TWVs) that significantly decreased electrical impedance per element, and hence the improved electrical impedance matching to T/R electronics and improved signal to noise ratio is disclosed. The TWVs facilitate integrated interconnection in single element transducers (positive and negative contact on the same side) and array transducers (contact pads array for integration with T/R switches and/or pre-amplifier circuits).