Abstract: A method of soldering terminals of a micro-speaker on a circuit board comprises the following steps. Firstly, providing a circuit board having a pair of through holes passing therethrough, and two soldering sections defined surrounding the pair of through holes. Secondly, the soldering sections are plated with soldering tin. Thirdly, providing a pair of columned terminals, the terminal includes an upper portion, a low portion and a body connecting between the upper portion and the low portion. Fourthly, the low portion of the terminal is inserted into the corresponding through hole and the body is resisted on the soldering section. Fifthly, the soldering tin is heated to solder the body on the soldering tin. Finally, the upper portion of the terminal is soldered onto the corresponding end of the voice coil. As a result, soldering defective can be reduced.

Abstract: An SAW device (1) has a piezoelectric substrate (3) propagating acoustic waves, and a comb-shaped electrode (6) arranged on a first surface (3a) of the piezoelectric substrate (3). The SAW device (1) has a columnar terminal (15) located on the first surface (3a) and electrically connected to the comb-shaped electrode (6), and a cover member (9) covering a side surface of the terminal (15). The terminal (15) comprises, in a first region in the direction of height thereof, a larger diameter on the side of the first surface (3a) compared with the diameter on the side opposite to the first surface (3a).

Abstract: The present invention in one aspect relates to an acoustic wave resonator having an acoustic reflector, a piezoelectric layer, a composite structure having a first electrode, a temperature compensation layer formed on the first electrode, having one or more vias or trenches formed therein, and a second electrode formed on the temperature compensation layer and electrically connected to the first electrode at least through the one or more vias or trenches, and a third electrode, where the composite structure is disposed under the piezoelectric layer, on the piezoelectric layer, or inside the piezoelectric layer.

Abstract: In one aspect, the disclosure provides an apparatus that includes an acoustic transducer, and a backing coupled to the transducer, wherein the backing includes solid grains with fluid between the grains.

Abstract: Replacement of a transducer assembly for an ultrasonic fluid meter. At least some of the illustrative embodiments are methods including: disconnecting a wiring harness that electrically couples electronics of an ultrasonic meter to a transducer assembly; removing the transducer assembly as a single unit from a transducer housing; inserting a replacement transducer assembly as a single unit into the transducer housing; and reconnecting the wiring harness.

Abstract: According to certain described aspects, multiple acoustic sensing elements are employed in a variety of beneficial ways to provide improved physiological monitoring, among other advantages. In various embodiments, sensing elements can be advantageously employed in a single sensor package, in multiple sensor packages, and at a variety of other strategic locations in the monitoring environment. According to other aspects, to compensate for skin elasticity and attachment variability, an acoustic sensor support is provided that includes one or more pressure equalization pathways. The pathways can provide an air-flow channel from the cavity defined by the sensing elements and frame to the ambient air pressure.

Abstract: A loudspeaker including a frame and a toroidal magnet that is affixed to the rear of the frame. The toroidal magnet has a central passageway that opens into the frame. A cap is affixed to the rear of the magnet and closes the central passageway. A guide rod is affixed to the cap and projects forwardly from the cap into the central passageway. A tubular former is slidably positioned upon the guide rod. A voice coil is wound about, and is affixed to, the tubular former. A driver plate is affixed to the front of the tubular former. A resilient surround connects the periphery of the driver plate to the front of the frame. A suspension assembly resiliently connects the tubular former to the frame and has a pair of conical diaphragms that are secured together so as to form a bellows. A spider connects the bellows to the frame and another spider connects the bellows to the tubular former.

Abstract: A duplexer includes an FBAR band pass filter that can be easily embodied in single chip. A method for manufacturing the same includes the steps of forming a plurality of recesses in a substrate, forming an insulation layer on the substrate, and forming a plurality of filling-up layers that fill the recesses. The method also includes the step of forming a transmitting bandpass filter and forming a receiving bandpass filter on an upper side of the membrane, with each bandpass filter including at least two film bulk acoustic resonators (FBARs). In addition, the method includes the step of forming a circuit that connects the bandpass filters to an antenna terminal, with this circuit including at least one inductor and capacitor. The method also includes a step of removing the filling-up layers from the recesses in the substrate.

Abstract: An exemplary magnetic diaphragm is applied to an electro-acoustic transducer. The magnetic diaphragm has a base formed with a magnetic layer thereon by a film deposition method. The base with the magnetic layer thus has magnetism to interference with a magnetic circuit of the electro-acoustic transducer. A manufacture method of the magnetic diaphragm is also disclosed.

Abstract: A differential microphone having a perimeter slit formed around the microphone diaphragm that replaces the backside hole previously required in conventional silicon, micromachined microphones. The differential microphone is formed using silicon fabrication techniques applied only to a single, front face of a silicon wafer. The backside holes of prior art microphones typically require that a secondary machining operation be performed on the rear surface of the silicon wafer during fabrication. This secondary operation adds complexity and cost to the micromachined microphones so fabricated. Comb fingers forming a portion of a capacitive arrangement may be fabricated as part of the differential microphone diaphragm.

Abstract: A variable directional microphone assembly and method of manufacturing the same, which includes a printed circuit board including a connection terminal provided to a surface thereof, and a semiconductor integrated circuit device mounted to another surface thereof, a microphone body including a first mounting space for mounting the semiconductor integrated circuit device, two second mounting spaces, and a coil spring insertion hole, the first mounting space being provided to a surface of the microphone body, the second mounting spaces being provided to another surface of the microphone body, two microphone devices mounted to the second mounting spaces, the insertion hole allowing the microphone device to be in contact with the printed circuit board, a coil spring inserted into the coil spring insertion hole to electrically connect the microphone device to the printed circuit board, and a case including a sound hole in a bottom thereof.

Abstract: A transducer stack (10) includes rings (16) of piezo-electric ceramic alternating with metal electrodes (18) along a threaded central shaft (32) extending from a titanium back plate (20). A spacer or threaded element (14) threaded on to the shaft (32) holds the ceramic rings (16) and electrodes (18) in compression against the back plate (20). The transducer stack (10) is mountable eccentrically to a horn (12) of an ultrasonically-vibratable tool, away from an axis of an elongate waveguide (56) extending from the horn (12). The transducer stack (10) may vibrate in a flexural mode perpendicular to the waveguide (56), generating torsional mode ultrasonic vibrations in the horn (12) and waveguide (56), or in a flexural mode parallel to the waveguide (56), generating longitudinal mode ultrasonic vibrations in the horn (12) and waveguide (56).

Abstract: An ultrasonic surgical assembly includes an ultrasonic transducer operable to convert a received motional voltage into a movement of a cutting blade of an ultrasonic waveguide, a motional feedback circuit connected in a parallel configuration with the transducer, a variable power source operable to apply a first voltage between a set of connection points to the parallel configuration, a voltage meter operable to determine a feedback voltage measured from the motional feedback circuit, and a voltage controller operable to vary an output of the power source based upon the measured feedback voltage, resulting in a substantially constant feedback voltage and maintaining a substantially constant rate of movement of the cutting blade across a variety of cutting loads.

Abstract: The patent application describes a switching power supply, wherein the supply has a first output voltage, wherein the first output voltage was generated by a first working voltage with a first frequency and a first phase, wherein the supply is adapted to configure the first frequency and/or the first phase in such a way that disturbances m devices powered by the supply are reduced, wherein the disturbances are caused of electromagnetic interferences. In an embodiment the switching power supply is adapted to configure the first frequency in such a way that the first frequency and its harmonies are different from the operating frequency of the powered device.

Abstract: An ultrasonic surgical assembly includes an ultrasonic transducer operable to convert a received motional current into a movement of a cutting blade of an ultrasonic waveguide, a measurement circuit connected in a parallel configuration with the ultrasonic transducer, a variable power source operable to supply current through a set of connection points to the parallel configuration and thereby create the motional current in the ultrasonic transducer, and a current controller operable to regulate the motional current by varying an output of the variable power source, thereby maintaining a substantially constant rate of movement of the cutting blade across a variety of cutting loads.

Abstract: An ultrasonic surgical assembly includes an ultrasonic-movement-generator assembly having a shell and an ultrasonic-driving-wave-signal generating circuit housed within the shell, an ultrasonic transducer having a proximal end and an ultrasonic-movement-producing distal end, an ultrasonic waveguide having a proximal end for receiving ultrasonic movement thereat, and a handle body having a waveguide attachment dock operable to accept the waveguide therein, an ultrasonic-movement-generator assembly dock operable to selectively removably secure the ultrasonic-movement-generator assembly thereto, and a transducer attachment dock operable to substantially simultaneously selectively removably and rotatably freely couple the ultrasonic transducer to the handle body rotationally independent of the ultrasonic-movement-generator assembly and axially align the ultrasonic-movement-producing distal end opposite the proximal end of the ultrasonic waveguide when the ultrasonic waveguide is disposed within the waveguide atta

Abstract: A sound transducer structure includes a membrane, a counter electrode, and a plurality of elevations. The membrane includes a first main surface, made of a membrane material, in a sound transducing region and an edge region of the membrane. The counter electrode is made of counter electrode material, and includes a second main surface arranged in parallel to the first main surface of the membrane on a side of a free volume opposite the first main surface of the membrane. The plurality of elevations extend in the sound transducing region from the second main surface of the counter electrode into the free volume.

Abstract: A method for assembling an ultrasonic surgical device includes the steps of providing a proximal end of an ultrasonic waveguide at an ultrasonic surgical handle body, removably coupling an ultrasonic-movement-generator assembly having a ultrasonic-driving-wave-signal generating circuit to the ultrasonic surgical handle body, mechanically coupling an ultrasonic transducer rotationally freely and substantially longitudinally fixedly to the ultrasonic surgical handle body to place an ultrasonic-movement-producing distal end of the ultrasonic transducer opposite and adjacent the proximal end of the ultrasonic waveguide, and rotating the waveguide and the ultrasonic transducer with respect to one another to removably fixedly couple the waveguide to the ultrasonic-movement-producing distal end of the ultrasonic transducer and to electrically couple the ultrasonic-driving-wave-signal generating circuit to the ultrasonic surgical handle body.

Abstract: A structure of wireless receiver includes a metallic casing, a positioning base, a receiving module, and a housing. The metallic casing has a circumferential wall defining an accommodating space therein, and two opposite ends thereof formed with an insertion hole and a through hole in communication with the accommodating space. The positioning base has a mounting trough, and is disposed in the accommodating space of the metallic casing. The positioning base has two side ends being fixed to the circumferential wall. The mounting trough is in communication with the accommodating space and the through hole. The receiving module is disposed in the mounting trough of the positioning base via the through hole of the metallic casing. The housing is assembled to the through hole of the metallic casing, and the through hole is sealed by the housing to block the receiving module.

Abstract: A method for producing a tuning-fork type crystal vibrating piece relates to a crystal tuning fork comprising a basal portion, a first vibrating arm, and a second vibrating arm, wherein both arms extend from the basal portion. The method for producing a crystal tuning fork comprises a step of forming a first metallic film into a shape including the contours of the basal portion, the first vibrating arm and second vibrating arm on a first surface of a quartz wafer; a step of forming a second metallic film on the second surface opposite to the first surface of the quartz wafer into a shape covering at least a root area near the basal portion between the first vibrating arm and the second vibrating arm, and a step of wet-etching the quartz substrate in etching solution after forming the first and second metallic films.

Abstract: A transducer assembly for an ultrasonic flow meter comprises a piezoelectric capsule. In an embodiment, the piezoelectric capsule includes a housing having a central axis, a first end, a second end opposite the first end, and a first inner chamber extending axially from the first end. In addition, the piezoelectric capsule includes a piezoelectric element disposed in the first inner chamber. Further, the piezoelectric element includes a plurality of spacers disposed in the first inner chamber between the piezoelectric element and the housing.

Abstract: The patent application discloses a capacitive micromachined ultrasound transducer, comprising a silicon substrate; a cavity; a first electrode, which is arranged between the silicon substrate and the cavity; wherein the first electrode is arranged under the cavity; a membrane, wherein the membrane is arranged above the cavity and opposite to the first electrode; a second electrode, wherein the second electrode is arranged above the cavity and opposite to the first electrode; wherein the second electrode is arranged in or close to the membrane, wherein the first electrode and the second electrode are adapted to be supplied by a voltage; and a first isolation layer, which is arranged between the first electrode and the second electrode, wherein the first isolation layer comprises a dielectric. It is also described a system for generating or detecting ultrasound waves, wherein the system comprises a transducer according to the patent application.

Abstract: The production of a hearing aid device can be simplified by the use of a microphone module with a plurality of microphones. To attach and electrically contact the microphones, the invention provides a microphone carrier with three-dimensionally directed conductor traces in MID technology. In a complicated microphone arrangement with a plurality of microphones, a single microphone module can thereby be used on which all microphones of the hearing aid device are attached and electrically connected.

Abstract: A fabricating method for an earphone includes the steps of: providing a front case and a speaker, the front case having a plurality of securing holes and a accommodating space, the speaker being disposed in the accommodating space; electrically connecting an earphone wire to the speaker; providing a rear case and securing the rear case onto the front case by making use of a plurality of fasteners penetrating through the rear case and fitted into the securing holes of the front case, and thereby the speaker is fixed in the accommodating space by the stop effect of the rear case; and buckling a protecting cover on the rear case to cover the fasteners. The fabricating method can make the produced earphone to be more reliable and thus can effectively avoid from being disassembled caused by an external force or unexpected falling, and therefore the internal components thereof can be effectively protected from damage.

Abstract: Provided is a method of manufacturing a capacitive electromechanical transducer, including: forming a lower electrode layer on a substrate; forming a sacrificial layer on the lower electrode layer; forming by application a resist layer on the sacrificial layer to form a cavity pattern; forming an insulating layer above regions including a region that contains the resist layer used to form the cavity pattern, and then removing a part of the insulating layer that is formed above the resist layer along with the resist layer, thereby leaving the insulating layer in the other regions than the region where the cavity pattern has been formed; forming a vibrating film above the region where the cavity pattern has been formed and the regions where the insulating layer remains; and removing the sacrificial layer to form a cavity.

Abstract: A composite membrane acoustic transducer structure comprising a magnet assembly is arranged adjacent the composite membrane material. The magnet assembly is arranged to produce a flux field. A first layer of thin, elongate composite membrane material is held under tension. A second conductive layer is attached to the first layer of composite membrane material wherein the first and second layers of membrane material are arranged adjacent, generally parallel and offset from the magnet assembly. The assembly is arranged to produce the flux field through at least part of the first layer and the second layer.

Abstract: The present invention is to provide a speaker magnetic circuit which, even if small in its thickness, can reduce an occurrence of magnetic flux leakage so as to obtain a sufficient magnetic flux density in a magnetic gap, particularly in a position where a voice coil is supported. The speaker magnetic circuit (11) comprises a yoke (12) and a magnet group (13). The magnet group (13) comprises outer magnets (21-24) and inner magnets (25-28). The outer magnets (21-24) and the inner magnets (25-28) are magnetized in an oblique direction with respect to their thickness direction.

Abstract: There is provided a gooseneck condenser microphone that is further strengthened the shield structure of a support pipe and is less prone to causing a trouble. This condenser microphone has a support pipe 30 for supporting a condenser microphone unit 10 and an output module part 20, a microphone cable 40 in which a shielding wire 44 is exposed is inserted in the support pipe 30, and a conductive sealant agent 50 is filled in a void between the microphone cable 40 and the support pipe 30.

Abstract: The production of a hearing aid device suitable for wireless signal transmission is simplified by providing fastening elements connected as one piece with the housing shell. The fastening elements serve for placement and fastening of an antenna or coil in the housing shell of the appertaining hearing aid device. The production of a hearing aid device with a corresponding antenna or coil is thereby simplified. The alignment of the antenna or coil in the housing shell can also already be optimized using a computer model of the housing shell.

Abstract: A capacitive microphone and method for making the same are provided. A backplate with a plurality of holes is formed on a substrate with at least one cavity, and a diaphragm is formed above the backplate. There is an air gap between the backplate and the diaphragm. The air gap and the cavity communicate with each other by each hole. The diaphragm and the backplate are separated by a first distance and a second distance which is smaller than the first distance, such that the difference is formed on the diaphragm. The second distance area is fastened through surface stiction produced by mist or other fluids.

Abstract: In a piezoelectric speaker, an acoustic diaphragm is thicker than a piezoelectric thin film and is formed of a more flexible and higher elasticity material than the piezoelectric thin film, thereby greatly improving output sound pressure in a low frequency band and reducing sound distortion. Further, the piezoelectric thin film is attached to the acoustic diaphragm in an inclined structure in which the piezoelectric thin film is horizontally turned from the acoustic diaphragm, thereby preventing a standing wave from being created by structural symmetry and minimizing sound distortion.

Abstract: An earphone and method for forming the same are provided. The earphone includes an earphone housing, a speaker, and an earcap. The earphone housing includes a speaker mounting portion. The speaker is fixed to the earphone housing, and has a cable that passes through the body and is drawn from the body. The earcap is installed to at least partially enclose the speaker and the housing, and has at least one speaker sound emitting hole therein. The earcap is made of a material that solidifies after a predetermined time elapses, and is manufactured by inserting the material into an ear of a user, and then solidifying the material such that it is suited for a shape of the ear of the user.

Abstract: In a loud speaker, the diaphragm has a protruded part protruding on a yoke side on the inside and in the vicinity of an inner coupling part as a coupled portion to a voice coil. The loud speaker can be manufactured with the voice coil accurately positioned with respect to a diaphragm, and the voice coil is accurately vibrated vertically inside a magnetic gap. The possibility of the voice coil coming into contact with a plate and a yoke as a magnetic circuit body of the loud speaker can be reduced, thereby to improve production efficiency and a yield at the time of manufacturing the loud speaker.

Abstract: A method for manufacturing an acceleration sensing unit includes: providing an element support substrate in which a plurality of element supporting members is arranged so as to form a plane, each of the element supporting members being coupled to the other element supporting member through a supporting part and having a fixed part and a movable part that is supported by the fixed part through a beam, the beam having a flexibility with which the movable part is displaced along an acceleration detection axis direction when an acceleration is applied to the movable part; providing an stress sensing element substrate in which a plurality of stress sensing elements is arranged so as to form a plane, each of the stress sensing elements being coupled to the other stress sensing element through an element supporting part and having a stress sensing part and fixed ends that are formed so as to have a single body with the stress sensing part at both ends of the stress sensing part; disposing the stress sensing element

Abstract: To provide a method for manufacturing a piezoelectric resonator which can conduct frequency matching with high reliability when performing rough adjustment of the frequency by adjusting the shape of a piezoelectric oscillating piece before forming an electrode film, and thereby it becomes possible to avoid reduction of the yield. Etching for forming the shape of a piezoelectric oscillating piece, and etching for forming grooves are conducted simultaneously, and after forming the grooves, the shape formation of the piezoelectric oscillating piece is started again from the same depth as the groove in a state of covering the groove with a metal film, and after the shape formation, matching of frequency is conducted by etching the side surface of the piezoelectric oscillating piece in succession. By composing such a structure, it is possible to conduct rough adjustment of frequency at a low etching rate so that the frequency matching can be performed with no due difficulty and with high accuracy.

Abstract: A microphone and a method for manufacturing the same. The microphones includes a substrate die; and a microphone and an accelerometer formed from the substrate die. The accelerometer is adapted to provide a signal for compensating mechanical vibrations of the substrate die.

Abstract: A method of manufacturing a piezoelectric vibrator comprises forming a gettering metal film on a surface of a piezoelectric vibrator piece and forming a frequency-adjusting weight, separate from the gettering metal film, on the piezoelectric vibrator piece. The piezoelectric vibrator piece is then placed in a hermetic container after which the hermetic container is hermetically sealed. A laser beam is irradiated on the metal film to heat the same to getter gas contained inside the hermetic container, and after completion of gettering, the laser beam is irradiated on the frequency-adjusting weight to adjust the frequency of vibration of the piezoelectric vibrator piece.

Abstract: A plurality of application specific integrated circuit (ASIC) chips with different functions is provided. Each of the ASICs performs one or more functions along an ultrasound data path. The chips include communications protocols or processes for allowing scaling. For example, ASICs for backend processing include data exchange ports for communicating between other ASICs of the same type. As another example, receive beamformer ASICs cascade for beamformation. By providing ASICs implementing many or most of the ultrasound data path functions, with scalability, the same ASICs may be used for different system designs. A family of systems from high end to low-end using the same types of ASICs, but in different configurations, is provided.

Abstract: In the present invention, a plurality of condenser microphones is formed on a substrate. Then, charges are fixed to a dielectric film provided in each of the condenser microphones. After an amount of deposited charges of the dielectric film of each of the plurality of the condenser microphones is inspected by measuring capacitance of each condenser microphone while applying bias between the first electrode film thereof and the second electrode film thereof, the substrate is diced so that each of the condenser microphones is separated. Thus, at least the step of fixing charges is performed in a substrate state where the plurality of the condenser microphones is formed on the substrate. Therefore, the present invention contributes to enhancement of productivity in an assembly process of the condenser microphone and reduction in equipment costs.

Abstract: A boundary acoustic wave element includes an IDT electrode arranged at the interface between a piezoelectric substance and a dielectric layer, a heat dissipation film is arranged on the outer side surface of the dielectric layer or on the outer side surface of a sound-absorbing film laminated on the outer side of the dielectric layer, the heat dissipation film is arranged to have a portion that overlaps the IDT electrode in plan view, and the heat dissipation film is connected to a bump provided on the outer side surface of the sound-absorbing film, and is connected to a via-hole conductor that extends through the sound-absorbing film. The boundary acoustic wave element and a boundary acoustic wave device are excellent in a heat dissipation property and hence can provide enhanced electric power resistance, without causing an increase in chip size and an increase in the area of the mounting space.

Abstract: A capacitive ultrasonic transducer includes a first electrode, an insulating layer formed on the first electrode, at least one support frame formed on the insulating layer, and a second electrode formed space apart from the first electrode, wherein the first electrode and the second electrode define an effective area of oscillation of the capacitive ultrasonic transducer, and the respective length of the first electrode and the second electrode defining the effective area of oscillation is substantially the same.

Abstract: The invention relates to a voice coil support (21) for a coil transducer motor structure (10) having a first surface (26) towards one end and a second surface (22) towards the other end along an axis of displacement Z, the voice coil support being adapted to receive at least one coil (22H, 22L) wound therearound an outer surface (27) arranged in use for displacing the voice coil support (21) along its axis of displacement Z, as a current is driven through the coils (22H, 22L) when the voice coil support (21) is placed in a magnetic field, characterized in that the voice coil support (21) comprises a material adapted to prevent airflow communication between at least the first surface (26) and the second surface (22).

Abstract: A probe for an ultrasonic diagnostic apparatus and a method of manufacturing the same are disclosed. The probe includes a sound matching layer having a mounting groove, a piezoelectric member mounted on the mounting groove, a first connector interconnected to the sound matching layer, and a second connector interconnected to the piezoelectric member. The probe permits interconnection of the piezoelectric member to the first and second connectors to be performed rapidly and easily through a single bonding operation, thereby reducing manufacturing time while facilitating the manufacture of the probe.

Abstract: A method for packaging micro electromechanical systems (MEMS) microphone has steps of providing a base, arranging and mounting multiple microphone component assemblies on the base, providing a frame, mounting the frame on the base, forming multiple microphone units, providing a cover; mounting the microphone units on the cover and forming multiple MEMS microphones. Therefore, the MEMS microphones can be produced once in large quantities to save production time and costs.

Abstract: In an electromechanical transducer which includes a vibration membrane provided with an upper electrode, a substrate provided with a lower electrode, and a support member adapted to support the vibration membrane in such a manner that a gap is formed between the vibration membrane and the substrate with these electrodes being arranged in opposition to each other, it is constructed such that a part of the vibration membrane and a region of the substrate are in contact with each other, and a remaining region of the vibration membrane other than the contact region is able to vibrate. There is an overlap region of the first electrode and second electrode in the contact region, and at least one of these electrodes has a through portion formed therethrough in at least a part of the overlap region.

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: An oscillator device having an oscillating member, a resilient support and a supporting member is produced. The oscillating member is supported by the resilient support for oscillation about an oscillation axis. The oscillating member is formed with a movable element having protrusions for adjusting its mass, the protrusions extending from the movable element parallel to the oscillation axis and being formed in pairs disposed at positions symmetrical with respect to the oscillation axis. A sectional area of each protrusion along a plane perpendicular to the oscillation axis is constant in the oscillation axis direction. A laser beam is projected to a cutting position of protrusions, so as to partly remove the protrusion. The protrusions are cut based on adjusting the cutting position. The sum of the lengths removed from the protrusions by the cutting becomes equal to a predetermined length to thereby adjust an inertia moment of the oscillating member.

Abstract: A microphone circuit includes a capacitor capsule and first and second impedance converters connected differentially to the capacitor capsule. The microphone circuit includes first and second output buffer amplifiers connected differentially to the first and second impedance converters.

Abstract: A linkage assembly (140) is used for mechanically coupling an armature (124) and a diaphragm (118) of a balanced receiver (100), the linkage assembly (140) formed from a first linkage member (822) displaced from a strip of stock material (800) relative to the plane of the stock material (800) and a second linkage member (826) displaced from the strip (800) relative to the plane. The first and second linkage members (822, 826) are then joined while secured to the strip (800). At least one severable connecting member (870a-c) securing the linkage member to the strip (800) is severed to release the linkage member from the strip for assembly of the linkage member into the receiver. A method of forming a three-dimensional structure from flat stock is used to form the linkage assembly (140).

Abstract: The present invention provides electroactive polymers, transducers and devices that maintain pre-strain in one or more portions of an electroactive polymer. Electroactive polymers described herein may include a pre-strained portion and a stiffened portion configured to maintain pre-strain in the pre-strained portion. One fabrication technique applies pre-strain to a partially cured electroactive polymer. The partially cured polymer is then further cured to stiffen and maintain the pre-strain. In another fabrication technique, a support layer is coupled to the polymer that maintains pre-strain in a portion of an electroactive polymer. Another embodiment of the invention cures a polymer precursor to maintain pre-strain in an electroactive polymer.