1433results about How to "High impedance" patented technology

An electrosurgical system comprises a radio frequency generator (1), an electrosurgical instrument (E1), and a fluid enclosure (42). The generator (1) has a radio frequency output for delivery of power to the electrosurgical instrument (E1) when immersed in an electrically-conductive fluid. The electrosurgical instrument (E1) has an electrode assembly (32) at the distal end thereof, the electrode assembly comprising a tissue treatment electrode (34), and a return electrode (38) axially spaced therefrom in such a manner as to define, in use, a conductive fluid path that completes an electrical circuit between the tissue treatment electrode and the return electrode. The fluid enclosure (42) is adapted to surround an operation site on the skin of a patient or an incision leading to a cavity surgically created within the patient's body. The fluid enclosure (42) includes sealing means (44) for sealing against the patient's tissue, and the fluid enclosure includes at least one port (50a, 52a) through which the electrosurgical (E1) is insertable, and through which the electrically-conductive fluid can enter and / or leave the enclosure.

An electrosurgical system comprises a radio frequency generator (1), an electrosurgical instrument (E1), and a fluid enclosure (42). The generator (1) has a radio frequency output for delivery of power to the electrosurgical instrument (E1) when immersed in an electrically-conductive fluid. The electrosurgical instrument (E1) has an electrode assembly (32) at the distal end thereof, the electrode assembly comprising a tissue treatment electrode (34), and a return electrode (38) axially spaced therefrom in such a manner as to define, in use, a conductive fluid path that completes an electrical circuit between the tissue treatment electrode and the return electrode. The fluid enclosure (42) is adapted to surround an operation site on the skin of a patient or an incision leading to a cavity surgically created within the patient's body. The fluid enclosure (42) includes sealing means (44) for sealing against the patient's tissue, and the fluid enclosure includes at least one port (50a, 52a) through which the electrosurgical (E1) is insertable, and through which the electrically-conductive fluid can enter and / or leave the enclosure. The fluid enclosure device of the present invention can also be used to treat tumours within the colon. The enclosure, which includes a proximal and a distal bung, is inserted into the colon in a deflated condition and then inflated with a conductive fluid or gas. The colon can be supported against the pressure of the fluid or gas with a pressure sleeve that has been inserted to surround the region of the colon being treated. An electrosurgical instrument is then inserted into the colon and manipulated to vaporize the tumor.

A system and method are disclosed for removing a uterus using a fluid enclosure inserted in the peritoneal cavity of a patient so as to enclose the uterus. The fluid enclosure includes a distal open end surrounded by an adjustable loop, that can be tightened, a first proximal opening for inserting an electrosurgical instrument into the fluid enclosure, and a second proximal opening for inserting an endoscope. The loop is either a resilient band extending around the edge of the distal open end or a drawstring type of arrangement that can be tightened and released. The fluid enclosure is partially inserted into the peritoneal cavity of a patient in a deflated condition and then manipulated within the peritoneal cavity over the body and fundus of the uterus to the level of the uterocervical junction. The loop is tightened around the uterocervical junction, after which the enclosure is inflated using a conductive fluid. The loop forms a pressure seal against the uterocervical junction to contain the conductive fluid used to fill the fluid enclosure. Endoscopically inserted into the fluid enclosure is an electrosurgical instrument that is manipulated to vaporize and morcellate the fundus and body of the uterus. The fundus and body tissue that is vaporized and morcellated is then removed from the fluid enclosure through the shaft of the instrument, which includes a hollow interior that is connected to a suction pump The fundus and body are removed after the uterus has been disconnected from the tissue surrounding uterus.

A method is disclosed for treating benign conditions, such as enlarged tonsils and / or adenoids located in a patient's throat or nasopharynx, or soft tissue lesions located in a patient's oropharynx or larynx. According to the method, a space containing the patient's nasopharynx, oropharynx or pharynx and larynx is isolated from the patient's trachea and lungs using an inflatable cuff tracheostomy tube or nasotracheal tube inserted in the patient's trachea. The cuff is inflated to occlude the trachea. The patient is placed in a supine position, whereupon at least a portion of the space containing the nasopharynx and / or oropharynx and larynx is filled with saline. An endoscope is then inserted into the space to view the operative site in which the tonsils or tissue lesion are to be treated. An electrosurgical instrument having an active tissue treatment electrode and a return electrode connected to an electrosurgical generator is then inserted into the space, either along side the endoscope or through the endoscope's working channel. The generator is then operated to apply a radio frequency voltage between the active and return electrodes of the electrosurgical instrument, whereby a conduction path is formed between the active and return electrodes, at least partially through the saline, whereupon the active electrode is manipulated to debulk or otherwise treat the soft tissue lesion or enlarged tonsils and / or adenoids.

A device for monitoring a rotating shaft is provided. The device measures strain in the shaft and provides angular velocity and torque in the shaft. The device includes a sensor, sensor conditioning circuitry, a microprocessor, and a transmitter, all located on a rotating shaft. The device obtains power by harvesting mechanical energy of the rotating shaft itself. Coils are provided rotating with the shaft and permanent magnets are mounted adjacent the rotating shaft so electrical energy is induced in the coils as they rotate through the magnetic field of the permanent magnets. A battery or capacitor is connected to the coils for storing energy. A microprocessor is connected to the sensors, the storage device, and the transmitter for managing power consumption and for monitoring the amount of electrical energy stored in the storage device and for switchably connecting the storage device to the transmitter when the stored energy exceeds a threshold.

A TANK filter is provided for a lead wire of an active medical device (AMD). The TANK filter includes a capacitor in parallel with an inductor. The parallel capacitor and inductor are placed in series with the lead wire of the AMD, wherein values of capacitance and inductance are selected such that the TANK filter is resonant at a selected frequency. In a preferred form, the TANK filter reduces or even eliminates the use of ferro-magnetic materials, and instead uses non-ferromagnetic materials so as to reduce or eliminate MRI image artifacts or the force or torque otherwise associated during an MRI image scan.

A sensor for use in the detection of a molecular interaction comprises a field effect transistor (FET) having a core structure and an extended gate structure, the core structure and the extended gate structure being located on substantially separate regions of a substrate, the extended gate structure including an exposed metal sensor electrode on which probe molecules can be immobilized, wherein, in use, the sensor is operative to produce a change in an electrical characteristic of the FET in response to molecular interaction at the exposed surface of the metal sensor electrode. The sensor is particularly suitable for detecting biomolecular interactions such as the hybridization of DNA, when the sensor is prepared with suitable probe molecules immobilized on the exposed gate metal.

A backplane for an electro-optic display comprises a pixel electrode (104), a voltage supply line (C) arranged to supply a voltage to the pixel electrode (104), and a micromechanical switch (106, 112) disposed between the voltage supply line (C) and the pixel electrode (104), the micromechanical switch (106, 112) having an open state, in which the voltage supply line (C) is not electrically connected to the pixel electrode (104), and a closed state, in which the voltage supply line (C) is electrically connected to the pixel electrode (104).

A device for monitoring a rotating shaft is provided. The device measures strain in the shaft and provides angular velocity and torque in the shaft. The device includes a sensor, sensor conditioning circuitry, a microprocessor, and a transmitter, all located on a rotating shaft. The device obtains power by harvesting mechanical energy of the rotating shaft itself. Coils are provided rotating with the shaft and permanent magnets are mounted adjacent the rotating shaft so electrical energy is induced in the coils as they rotate through the magnetic field of the permanent magnets. A battery or capacitor is connected to the coils for storing energy. A microprocessor is connected to the sensors, the storage device, and the transmitter for managing power consumption and for monitoring the amount of electrical energy stored in the storage device and for switchably connecting the storage device to the transmitter when the stored energy exceeds a threshold.

Provided is a plasma processing apparatus in which an external circuit is electrically connected, via a line, to a predetermined electric member within a processing container thereof, and noises of first and second high frequency waves are attenuated or blocked by a filter provided on the line when the noises enter the line from the electric member toward the external circuit. The filter includes: an air core coil provided at a first stage when viewed from the electric member side; a toroidal coil connected in series with the air core coil; an electroconductive casing configured to accommodate or enclose the air core coil and the toroidal coil; a first condenser electrically connected between a connection point between the air core coil and the toroidal coil and the casing; and a second condenser connected between a terminal of the toroidal coil at the external circuit side and the casing.

Some embodiments are directed to MRI / RF compatible medical interventional devices. A plurality of spaced apart high impedance circuit segments are configured to have a high impedance at a high range of radiofrequencies and a low impedance at a low range of frequencies The high impedance circuit segments may comprise co-wound coiled inductors and can reduce, block or inhibit RJ-transmission along the lead system (20) during exposure to RF associated with a high-Held magnet MRI systems, while permuting passage of low frequency physiologic signals, treatments and / or stimuli The devices can include at least one electrode

A bipolar forceps includes an end effector assembly having opposing first and second jaw members each having a proximal end and a distal end. The jaw members are movable relative to each other in order to grasp tissue therebetween. An electrically conductive surface having two or more conductive sealing plates and a dielectric layer is operably coupled to the first jaw member. Each sealing plate is connected to a reactive element and positioned along the electrically conductive surface from the proximal end to the distal end. The reactive element of the sealing plate positioned on the proximal end of the first jaw member has a different impedance than the reactive element positioned on the distal end. An electrically conductive surface having one or more conductive sealing plates is operably coupled to the second jaw member. Each electrically conductive surface on the jaw members connects to a source of electrosurgical energy such that the sealing plates are capable of conducting energy through tissue held therebetween to effect a tissue seal.

A plasma processing apparatus includes a processing chamber, a first electrode and a second electrode disposed to face each other, a high frequency power supply unit for applying a high frequency power to either the first electrode or the second electrode, a processing gas supply unit for supplying a processing gas to a processing space, and a main dielectric member provided at a substrate mounting portion on a main surface of the first electrode. A focus ring is attached to the first electrode to cover a peripheral portion of the main surface of the first electrode and a peripheral dielectric member is provided in a peripheral portion on the main surface of the first electrode so that an electrostatic capacitance per unit area applied between the first electrode and the focus ring is smaller than that applied between the first electrode and the substrate by the main dielectric member.

Ultrasound bulk wave transducers and bulk wave transducer arrays for wide band or multi frequency band operation, in which the bulk wave is radiated from a front surface and the transducer is mounted on a backing material with sufficiently high absorption that reflected waves in the backing material can be neglected. The transducer is formed of layers that include a high impedance section comprised of at least one piezoelectric layer covered with electrodes to form an electric port, and at least one additional elastic layer, with all of the layers of the high impedance section having substantially the same characteristic impedance to yield negligible reflection between the layers. The transducer further includes a load matching section comprised of a set of elastic layers for impedance matching between the high impedance section and the load material and, optionally, impedance matching layers between the high impedance section and the backing material for shaping the transducer frequency response. For multiband operation, the high impedance section includes multiple piezoelectric layers covered with electrodes to form multiple electric ports that can further be combined by electric parallel, anti-parallel, serial, or anti-serial galvanic coupling to form electric ports with selected frequency transfer functions. Each electric port may be separately transceiver-connected to obtain parallel, anti-parallel, serial or anti-serial port coupling for multi-band transmission, and extremely wide-band reception.

Medical apparatus includes a pacing generator, which has first active and indifferent outputs and is configured to generate electrical pacing pulses between the first active and indifferent outputs for pacing a heart of a subject. A radio frequency (RF) generator has second active and indifferent outputs and is configured to generate RF electrical energy of a predetermined frequency between the second active and indifferent outputs for application to the heart of the subject simultaneously with the pacing pulses. A filter includes a first branch connected between the first and second active outputs and a second branch connected between the first and second indifferent outputs, each of the first and second branches including one or more notch filters having a high impedance in a vicinity of the frequency of the RF electrical energy.

An body implantable stimulation lead is provided including tip electrode patterns and configurations producing low noise, clean sensed signals devoid of far field components, such sensed signals being generated irrespective of the direction of the incident depolarization wavefront. The invention also provides high pacing impedances and advantageous anode-to-cathode surface area ratios. Further, implantable leads utilizing the features of the present invention are particularly suitable for left side stimulation therapies.

A memory element, a threshold switching element, or the series combination of a memory element and a threshold switching element may be used for coupling conductive lines in an electrically programmable matrix array. Leakage may be reduced by optionally placing a breakdown layer in series with the phase-change material and / or threshold switching material between the conductive lines. The matrix array may be used in a programmable logic device.

A device for powering a load from an ambient source of energy is provided. The device includes an energy harvesting device for harvesting energy from the ambient source of energy wherein the rate energy is harvested from the ambient source of energy is below that required for directly powering the load. A storage device is connected to the energy harvesting device. The storage device receives electrical energy from the energy harvesting device and is for storing the electrical energy. A controller is connected to the storage device for monitoring the amount of electrical energy stored in the storage device and for switchably connecting the storage device to the load when the stored energy exceeds a first threshold. The system can be used for powering a sensor and for transmitting sensor data, such as tire pressure.

A method of estimating stroke volume of the heart, comprising: taking a first set of electrical data of the chest at a first phase of the cardiac cycle; estimating a first volume of the heart from the first set of electrical data; taking a second set of electrical data of the chest at a second phase of the cardiac cycle; estimating a second volume of the heart from the second set of electrical data; and using the difference between the first and second volumes of the heart to estimate the stroke volume of the heart.

A system having a UHF RFID transceiver is adapted to communicate exclusively with a single electro-magnetically coupled transponder located in a predetermined confined transponder operating region. The system includes a near field coupling device comprising a plurality of lines connected in parallel with an unmatched load. The near field coupling device may be formed, for example on a printed circuit board with a plurality of electrically interconnected traces and a ground plane. The system establishes, at predetermined transceiver power levels, a mutual electro-magnetic coupling which is selective exclusively for a single transponder located in a defined transponder operating region. Also included are methods for selective communication with the transponder in an apparatus such as a printer-encoder.

A method for measuring a neural response to a stimulus. Measurement circuitry is settled prior to a stimulus, by connecting a sense electrode to the measurement circuitry to allow the measurement circuitry to settle towards a bio-electrically defined steady state. Charge is recovered on stimulus electrodes by short circuiting the stimulus electrodes to each other. An electrical stimulus is then applied from the stimulus electrodes to neural tissue, while keeping the sense electrode disconnected from the measurement circuitry. After the stimulus, a delay is imposed during which the stimulus electrodes are open circuited and the sense electrode is disconnected from the measurement circuitry and from the stimulus electrodes. After the delay, a neural response signal present at the sense electrode is measured by connecting the sense electrode to the measurement circuitry.

The present invention relates to an audio signal controller adapted to receiving first and second digital audio signals and estimating a signal feature of the first or second digital audio signal. The estimated signal feature is compared with a predetermined feature criterion and the audio signal controller switches from conveying the first digital audio signal to conveying the second digital audio signal to a controller output, or vice versa, at a zero-crossing of the first digital audio signal or the second digital audio signal based on the comparison between the estimated signal feature and the predetermined feature criterion.

Body tissue ablation is carried out by inserting a probe into a body of a living subject, urging the probe into contact with a tissue in the body, generating energy at a power output level, and transmitting the generated energy into the tissue via the probe. While transmitting the generated energy the ablation is further carried out by determining a measured temperature of the tissue and a measured power level of the transmitted energy, and controlling the power output level responsively to a function of the measured temperature and the measured power level. Related apparatus for carrying out the ablation is also described.

A surge protection device is disclosed that includes an input path for receiving an rf signal, dc power, and a surge, an output path for propagating the rf signal, and a dc blocking device coupled in series between the input path and the output path. The surge protection device also includes a first inductor coupled to the input path for isolating the rf signal and providing a path for the dc power, a gas tube coupled to the first inductor for routing a portion of the surge to a ground plane, a second inductor coupled to the first inductor for providing a path for the dc power, and a metal oxide varistor coupled to the second inductor for routing a portion of the surge to the ground plane. Furthermore, the surge protection device includes a third inductor coupled to the second inductor for providing a path for the dc power, a diode coupled to the third inductor for routing a portion of the surge to the ground plane, and a fourth inductor coupled to the third inductor for providing a path for the dc power to the output path.

An amplifier circuit responsive to a power mode signal improves efficiency at low power levels without compromising efficiency at high power levels. At low power levels, high impedance is presented with suitable adjustment in the phase of the signal. Also, providing for predistortion linearization improves high power efficiency and switching the predistortion linearizer OFF at low power levels contributes little more than a small insertion loss. The power amplifier also uses a bias circuit incorporating a dual harmonic resonance filter to provide high impedance at a fundamental frequency and low impedance at a second harmonic. These properties are of particularly advantageous since amplifiers in cell-phones are used in low power modes most of the time although they are designed to be most efficient at primarily the highest power levels.

A backplane for an electro-optic display comprises a pixel electrode (104), a voltage supply line (C) arranged to supply a voltage to the pixel electrode (104), and a micromechanical switch (106, 112) disposed between the voltage supply line (C) and the pixel electrode (104), the micromechanical switch (106, 112) having an open state, in which the voltage supply line (C) is not electrically connected to the pixel electrode (104), and a closed state, in which the voltage supply line (C) is electrically connected to the pixel electrode (104).

A device for powering a load from an ambient source of energy is provided. The device includes an energy harvesting device for harvesting energy from the ambient source of energy wherein the rate energy is harvested from the ambient source of energy is below that required for directly powering the load. A storage device is connected to the energy harvesting device. The storage device receives electrical energy from the energy harvesting device and is for storing the electrical energy. A controller is connected to the storage device for monitoring the amount of electrical energy stored in the storage device and for switchably connecting the storage device to the load when the stored energy exceeds a first threshold. The system can be used for powering a sensor and for transmitting sensor data, such as tire pressure.

A microchip for control of a switch mode power supply (SMPS), with said microchip also having the ability to measure capacitance of an electrode or sense plate structure or structures, and use of a low power, power supply structure to supply said microchip, said power supply structure distinct from the main energy path via said SMPS to a load. The microchip may control said SMPS to transition between an active state and an inactive state, with the measured capacitance used to determine a condition for state transition. In said SMPS inactive state, only the microchip draws power to operate its capacitive sensing circuitry, leading to a significant SMPS standby losses decrease compared to prior art. Further teachings by the present invention include capacitive sensing based data transfer, universal charging platforms for mobile devices, noise immunity enhancements, various lighting embodiments as well as SMPS operation improvements.

A smart patch including multi-component strands integrated into clothing or other textiles where the strands of the smart patch include sensory elements that can simultaneously measure tactile forces, moisture / wetness, and other signals, such as biopotentials. A sensing system comprising: a first set of strands including a plurality of first multi-component strands, each of the first multi-component strands including a conductive portion and a non-conductive portion; and a second set of strands including a plurality of second multi-component strands, each of the second multicomponent strands including a conductive portion and a non-conductive portion, and a plurality of third multi-component strands, each of the third multicomponent strands including a conductive portion and a non-conductive portion, the third multi-component strands being different than the first multi-component strands and the second multi-component strands.