Showing papers on "Electrode array published in 2003"

Implantable generator having current steering means

Abstract: An implantable pulse generator includes a current steering capability that allows a clinician or patient to quickly determine a desired electrode stimulation pattern, including which electrodes of a group of electrodes within an electrode array should receive a stimulation current, including the amplitude, width and pulse repetition rate of such current. Movement of the selected group of electrodes is facilitated through the use of remotely generated directional signals, generated by a pointing device, such as a joystick. As movement of the selected group of electrodes occurs, current redistribution amongst the various electrode contacts takes place. The redistribution of stimulus amplitudes utilizes re-normalization of amplitudes so that the perceptual level remains fairly constant. This prevents the resulting paresthesia from falling below the perceptual threshold or above the comfort threshold.

Impedance based devices and methods for use in assays

Abstract: A device for detecting cells and/or molecules on an electrode surface is disclosed. The device detects cells and/or molecules through measurement of impedance changes resulting from the cells and/or molecules. A disclosed embodiment of the device includes a substrate having two opposing ends along a longitudinal axis. A plurality of electrode arrays are positioned on the substrate. Each electrode array includes at least two electrodes, and each electrode is separated from at least one adjacent electrode in the electrode array by an expanse of non-conductive material. The electrode has a width at its widest point of more than about 1.5 and less than about 10 times the width of the expanse of non-conductive material. The device also includes electrically conductive traces extending substantially longitudinally to one of the two opposing ends of the substrate without intersecting another trace. Each trace is in electrical communication with at least one of the electrode arrays.

Electrosurgical probe having circular electrode array for ablating joint tissue and systems related thereto

Abstract: Electrosurgical methods, systems, and apparatus for the controlled ablation of tissue from a target site, such as a synovial joint, of a patient. An electrosurgical probe of the invention includes a shaft, and a working end having an electrode array comprising an outer circular arrangement of active electrode terminals and an inner circular arrangement of active electrode terminals. The electrode array is adapted for the controlled ablation of hard tissue, such as meniscus tissue. The working end of the probe is curved to facilitate access to both medial meniscus and lateral meniscus from a portal of 1 cm. or less.

Tumor treating device for use by surgeon, has generator applying voltage to each of active electrodes in manner independent from other electrodes and having sinusoidal voltage generation unit adjusting amplitude and phase of voltage

Abstract: The device has a high frequency electric generator (100) applying an alternative voltage between active transcutaneous electrodes (1-6) and a return electrode (120). The generator applies the voltage to each active electrode in a manner independent from other electrodes and has a sinusoidal voltage generation unit to adjust amplitude and phase of the voltage applied to each active electrode.

Backplanes for electro-optic displays

Abstract: 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).

Voltage modulated driver circuits for electro-optic displays

Abstract: A method and system for applying addressing voltages to pixels of a display involves receiving input data. The input data includes an indication of an addressing voltage impulse to be applied to a pixel via an electrode. One or more voltage sources are selected, to provide the addressing voltage impulse. The one or more voltage sources each have a pre-selected voltage. The selected one or more voltage sources are electrically connected to an electrode to apply the addressing voltage impulse to the pixel.

Differentially-driven MEMS spatial light modulator

Abstract: A MEMS SLM and an electrostatic actuator associated with a pixel in an SLM. The actuator has three electrodes: a lower electrode; an upper electrode fixed with respect to the lower electrode; and a center electrode suspended and actuable between the upper and lower electrodes. The center electrode is capable of resiliently-biasing to restore the center electrode to a non-actuated first equilibrium position, and a mirror is operably connected to the center electrode. A first voltage source provides a first bias voltage across the lower and center electrodes and a second voltage source provides a second bias voltage across the upper and center electrodes, with the first and second bias voltages determining the non-actuated first equilibrium position of the center electrode. A third voltage source provides a variable driver voltage across one of the lower/center and upper/center electrode pairs in series with the corresponding first or second bias voltage, to actuate the center electrode to a dynamic second equilibrium position.

Method for electrosurgical tissue treatment near a patient's heart

Abstract: An electrosurgical probe ( 10 ) comprises a shaft ( 13 ) having an electrode array ( 58 ) at its distal end and a connector ( 19 ) at its proximal end for coupling the electrode array to a high frequency power supply ( 28 ). The shaft includes a return electrode ( 56 ) recessed from its distal end and enclosed within an insulating jacket ( 18 ). The return electrode defines an inner passage ( 83 ) electrically connected to both the return electrode and the electrode array for passage of an electrically conducting liquid ( 50 ). By applying high frequency voltage to the electrode array and the return electrode, the electrically conducting liquid generates a current flow path between the return electrode and the electrode array so that target tissue may be cut or ablated. The probe is particularly useful in dry environments, such as the mouth or abdominal cavity, because the electrically conducting liquid provides the necessary return current path between the active and return electrodes.

Emg electrode apparatus and positioning system

Abstract: A system for dectecting and analyzing electrical activity in the anatomy of an organism underlying an electrode array provides signals corresponding to electrical activity adjacent each electrode. Such signals are correlated to the underlying anatomy of the organism and representative outputs presented through various types of output devices. Such outputs may include variations in coloration or other qualities in correspondence with representations of underlying anatomical structures. The system includes novel electrode structures (200, 224, and 284) and methods for producing and attaching electrodes arrays (240 and 280) to the organism. The exemplary form of the invention is used in connection with the diagnosis of muscle activity in the lower lumbar regions of humans. Levels of muscle activity detected are analyzed by correlation with the muscular structures underlying the electrode array. Forms of the invention may be used in other applications.

Theoretical assessment of a crossed electrode 2-D array for 3-D imaging

Abstract: A crossed electrode two-dimensional (2-D) transducer array is described. The array permits real-time three-dimensional imaging using a small fraction of the elements required by a full two-dimensional array. Using this approach, the number of elements in an N/spl times/N 2-D array is reduced by a factor of N/4. Simulation results show that a radiation pattern comparable to one produced by a conventional linear phased array with a 50 wavelength aperture can be obtained using a crossed electrode array with 200 transmit and receive elements.

A miniaturized neuroprosthesis suitable for implantation into the brain

Abstract: This paper presents current research on a miniaturized neuroprosthesis suitable for implantation into the brain. The prosthesis is a heterogeneous integration of a 100-element microelectromechanical system (MEMS) electrode array, front-end complementary metal-oxide-semiconductor (CMOS) integrated circuit for neural signal preamplification, filtering, multiplexing and analog-to-digital conversion, and a second CMOS integrated circuit for wireless transmission of neural data and conditioning of wireless power. The prosthesis is intended for applications where neural signals are processed and decoded to permit the control of artificial or paralyzed limbs. This research, if successful, will allow implantation of the electronics into the brain, or subcutaneously on the skull, and eliminate all external signal and power wiring. The neuroprosthetic system design has strict size and power constraints with each of the front-end preamplifier channels fitting within the 400 /spl times/ 400-/spl mu/m pitch of the 100-element MEMS electrode array and power dissipation resulting in less than a 1/spl deg/C temperature rise for the surrounding brain tissue. We describe the measured performance of initial micropower low-noise CMOS preamplifiers for the neuroprosthetic.

Biosenser having electrode for determining the rate of flow of a fluid

Abstract: Sensors that are capable measuring the rate of flow of a fluid that passes over the electrodes of the sensor. In these sensors, an electrode, designated the flow rate-determining electrode, is used in conjunction with the conventional electrodes, e.g., the working electrode, the reference electrode, and the counter electrode, to determine the rate of flow of the fluid. In one aspect, this invention provides a sensor for measuring the concentration of an analyte in a sample of fluid when the sample flows continuously over the electrodes of the sensor, especially when the rate of flow of the sample is relatively low. In another aspect, this invention provides a method for measuring the concentration of an analyte in a sample of fluid, wherein the rate of flow of the sample varies during the period of time that the sensor is in place. In a preferred embodiment, the sensor employs four electrodes, namely, a working electrode, a reference electrode, a counter electrode, and a flow rate-determining electrode. Alternatively, a single electrode that performs both the function of the reference electrode and the function of the counter electrode can replace the reference electrode and the counter electrode. In addition, a dummy electrode or a blank electrode can be used to compensate for interference from electrochemically active species. The reagent(s) specific to the analyte of interest is required to be deposited on the working electrode.

Speech recognition under conditions of frequency-place compression and expansion

Abstract: In normal acoustic hearing the mapping of acoustic frequency information onto the appropriate cochlear place is a natural biological function, but in cochlear implants it is controlled by the speech processor. The cochlear tonotopic range of the implant is determined by the length and insertion depth of the electrode array. Conventional cochlear implant electrode arrays are designed for an insertion of 25 mm inside the round window and the active electrodes occupy 16 mm, which would place the electrodes in a cochlear region corresponding to an acoustic frequency range of 500–6000 Hz. However, some implant speech processors map an acoustic frequency range from 150 to 10 000 Hz onto these electrodes. While this mapping preserves the entire range of acoustic frequency information, it also results in a compression of the tonotopic pattern of speech information delivered to the brain. The present study measured the effects of such a compression of frequency-to-place mapping on speech recognition using acoustic...

Apparatus and method for determining adequacy of electrode-to-skin contact and electrode quality for bioelectrical measurements

Abstract: A system and method for diagnosing the possibility of disease in a body part is described. The system includes an electrode array containing a plurality of electrodes capable of being electrically coupled to the body part. A first measurement unit makes an electrode assessment measurement with the electrode array. An electrode assessment module determines whether the plurality of electrodes are suitably coupled to the body part based on the electrode assessment measurement. If there is suitable coupling, a second measurement unit makes a diagnosis measurement with the electrode array. An electrical property module obtains an electrical property of the body part, such as impedance, based on the diagnosis measurement. A diagnosis module diagnoses the possibility of disease based on the measured electrical property.

Drive circuit, display apparatus, and information display apparatus

Abstract: The present invention relates to a configuration utilizing a driven element that is driven by a current Specifically, there is provided a pixel circuit having a driven element and a current-drive transistor for supplying a current for driving the driven element to a current injection terminal of the driven element, a voltage buffer, a current signal line for supplying a current signal to the pixel circuit, and a wiring for connecting an output of the voltage buffer and a gate electrode of the current drive transistor The pixel circuit has a switch for controlling connection between the voltage buffer and the gate electrode of the current-drive transistor, and an input terminal of the voltage buffer is connected to the current signal line

Personal electro-kinetic air transporter-conditioner

Abstract: A personal electro-kinetic electro-static air conditioner includes a self-contained ion generator that provides electro-kinetically moved air with ions and safe amounts of ozone, and includes a water retaining element to increase humidity of the output air flow. The ion generator includes a high voltage pulse generator whose output pulses are coupled between first and second electrode arrays. Preferably the first electrode array includes first and second pointed electrodes, and the second electrode array includes annular-like electrodes having a central opening coaxial with the associated pointed electrode. The surface of the annular-like electrodes is smooth and continuous through the opening and into a collar region through which the air flows. A water retaining member is disposed surrounding the output airflow to increase humidity of the output air, which is substantially cleansed of particulate matter, and contains safe amounts of ozone.

Band type multicontact electrode and method of making the same

Abstract: A multicontact electrode array suitable for implantation in living tissue includes a distal end having multiple spaced-apart ring or band electrode contacts carried on a flexible tube carrier. Each ring electrode contact is laser welded to a respective wire tip that has a multi-helix orientation on the inside of a separation tube. The center of the multi-helix wire defines a lumen wherein a positioning stylet, or other suitable positioning tool, may be removably inserted when the electrode array is implanted. The method of making the multicontact electrode array includes, as an initial step, winding lead wires around a suitable mandrel so as to form a multi-helix configuration. (Alternatively, the wire may be purchased in a multiwire pre-wound configuration that defines a lumen, in which case the mandrel is slipped inside the lumen.) Then, at a distal end of the electrode, each wire within the multi-helix winding is unwound so as to protrude out from the winding. Next, a non-conductive separation silicone tube which has a longitudinal slit along its length, is placed around the wound wires. Ring contacts are then placed over the silicone tube at a distal end of the electrode array and spaced apart as desired. These ring contacts also have a slit therein through which the protruding wire ends may exit. The silicone tube is used as a spacer to centrally locate the multi-helix wound wires with the ring contacts. A compressive die may be used to hold the pre-assembled ring contact, multi-helix wire, separation tube in their desired positions, and may be used to close the opening or slit of each ring contact through which the wire tips protrude. The wire tips are then individually trimmed to a suitable distance. A laser welding process may then be used to bond each lead wire to a corresponding ring contact. Finally, the preassembled electrode array is placed in a molding die, and a polymer filler is injected into the internal gaps of the electrode array components.

Variable pitch electrode array

Abstract: The present invention is an implantable electrode array having electrodes with variable pitch and variable size. Electrode arrays of the prior art provide electrodes with a common spacing and size. However, this is not how the human body is arranged. As an example, the retina has closely spaced retinal receptors near the fovea. Those receptors are spaced farther apart, farther away from the fovea. Further, the amount of electrical current required to stimulate the perception of light increases with distance from the fovea. Hence, larger electrodes are required to transfer the necessary current farther away from the fovea.

Method and device for image processing and learning with neuronal cultures

Abstract: It is disclosed a device for image processing and learning comprising at least a “multi electrode array” (MEA), over which an homogeneous culture of interconnected neurons, so that forming a cell network, is grown on, wherein said MEA is able to stimulate and record the electric activity of said neurons. Methods for image processing and learning utilizing the device are disclosed too.

Capacitance type sensor and method for manufacturing same

Abstract: In a capacitance type sensor of the present invention, a capacitance element is constituted between a displacement electrode and a capacitance element electrode. A return-switch movable electrode is arranged above and spaced from the displacement electrode, to be placed in contact with the displaying electrode due to a displacement of a direction button. When the direction button is operated, the return-switch movable electrode is first displaced into contact with the displacement electrode. Then, the both make a displacement while keeping a contact state. When the displacement electrode is displaced to change the spacing to the capacitance element electrode, changed is the capacitance value of the capacitance element. Based on this change, a force is recognized. Herein, in the course of a transit from a state the displacement electrode and the return-switch electrode are not in contact to a state of their contact, the output signal varies necessarily beyond a threshold voltage.

Forward masking in different cochlear implant systems.

Abstract: The goal of this study was to evaluate, from a psychophysical standpoint, the neural spread of excitation produced by the stimulation of different types of intracochlear electrode arrays: the Ineraid™, the Clarion™ S-Series on its own or with the Electrode Positioning System (EPS), and the Clarion™ HiFocus-I with the EPS. The EPS is an independent silicone part designed to bring the electrode array close to the modiolus. Forward masking was evaluated in 12 adult subjects (3 Ineraid™, 4 Clarion™ S-Series, 3 Clarion™ S-Series+EPS, 3 HiFocus-I+EPS) by psychophysical experiments conducted using trains of biphasic stimuli (813 pulses per second, 307.6 μs/phase). Masker signals (+8 dB re: threshold, 300 ms) were applied to the most apical electrode. Probe signals (30 ms, 10-ms postmasker) were delivered to more basal electrodes. Masked and unmasked detection thresholds of probe signals were measured. For both Clarion™ HiFocus-I subjects, measurements were conducted in both monopolar and bipolar stimulus configurations. No major differences were found in forward masking between the different intracochlear electrode arrays tested in the monopolar configuration at suprathreshold levels equivalent to those used in speech-coding strategies, but significant differences were found between subjects. A significant negative correlation also was found between the level of forward masking and the consonant identification performance. These measurements showed that the neural spread of excitation was more restricted in the bipolar configuration than in the monopolar configuration for HiFocus-I subjects. It was found that CIS strategies implemented without using apical electrodes, which showed high levels of masking, could improve consonant identification.

Method and apparatus for increasing performance of ion wind devices

Abstract: An electro-kinetic air conditioner for removing particulate from the air creates an airflow using no moving parts. The conditioner includes an ion generator that has an electrode assembly including a first array of emitter electrodes, a second array of collector electrodes, and a high voltage generator. Preferably, a third or leading or focus electrode is located upstream of the first array of emitter electrodes, and/or a trailing electrode is located downstream of the second array of collector electrodes. The device can also include an interstitial electrode located between collector electrodes, an enhanced collector electrode with an integrally formed trailing end, and an enhanced emitter electrode with an enhanced length in order to increase emissivity.

Method of positioning electrodes for central nervous system monitoring and sensing pain reactions of a patient

Abstract: A method concerning measurements by using an electrode array comprising three electrodes for central nervous system (CNS) monitoring from the forehead of a patient's head A first electrode of said three electrodes is positioned between the eyebrows or immediately above the eyebrows of the patient A third electrode of said three electrodes is positioned apart from the first electrode on the hairless fronto-lateral area of the forehead the patient A second electrode is positioned between the first and the third electrodes on the forehead of the patient

Electronic communications system, apparatus and electrode layout method

Abstract: An electric field generated by another electric field communications apparatus reaches electric field sensor ES. Electric field sensor ES outputs an electric signal in response to the changes in the electric field. The electric field that reaches electric field sensor ES enters a return path of the electric field communications apparatus that is a source of the electric field. By locating electric field sensor ES between receiver main electrode ERB and receiver return electrode ERG, electric field intensity at the location where electric field sensor ES is positioned. Therefore, sensitivity of the changes in electric field for electric field communications apparatus TRX can be improved.

Method of positioning electrodes for central nervous system monitoring

Abstract: Method of positioning electrodes in an electrode array, comprising at least five or at least seven electrodes for central nervous system (CNS) monitoring from the forehead of a patient's head. The electrodes of the array are optimally located for discriminating EEG, FEMG and EM components from the recorded biopotential signals.