2440 results about "Field strength" patented technology

According to the invention, a finger-operated switch for activating and operating an ultrasonic surgical handpiece is provided. The power output of the surgical handpiece is responsive and proportional to the pressure applied to the finger-operated switch. The finger-operated switch includes, but not limited to, force sensitive resistors whose resistance is proportional to the force applied by the finger of the human operator of the surgical handpiece, force sensitive capacitors whose capacitance is proportional to the pressure, deflection or compression of the insulation layer between two electrodes or is proportional to the spacing between the two conductive layers, strain gauges mounted underneath or integral to the housing of the surgical handpiece such that the pressure applied thereto results in an output change in the strain gauges, magnets or ferromagnets encased or embedded in an elastomer with a sensor inside the surgical handpiece that detects the field strength of the magnet and monitors changes relative to the force applied to the handpiece housing, and piezo film or piezo ceramic whose charge or voltage is proportional to the force applied.

An implantable biocompatible lead that is also compatible with a magnetic resonance imaging scanner for the purpose of diagnostic quality imaging is described. The implantable electrical lead comprises a plurality of coiled insulated conducting wires wound in a first direction forming a first structure of an outer layer of conductors of a first total length with a first number of turns per unit length and a plurality of coiled insulated conducting wires wound in a second direction forming a second structure of an inner layer of conductors of a second total length with a second number of turns per unit length. The first and the second structures are separated by a distance with a layer of dielectric material. The distance and dielectric material are chosen based on the field strength of the MRI scanner. The lead may further comprise a conducting layer formed by coating a material consisting of medium conducting particles in physical contact with each other and a mechanically flexible, biocompatible layer forming an external layer of lead and in contact with body tissue or body fluids.

A programming-device user interface may include multiple levels of abstraction for programming treatment settings. A stimulation zone-programming interface may be at a highest level of abstraction and may include idealized stimulation zones. A field strength-programming interface may be at a middle level of abstraction and may include electromagnetic field-strength patterns generated by the stimulation zones, and / or electrode settings, and a depiction of how the electromagnetic fields interact with each other. An electrode-programming interface may be at a lowest level of abstraction and may depict treatment settings at an electrodes-view level. These interfaces may include a display of a stimulatable area of the patient's body. The display may include a depiction of leads and / or the underlying physiology, such as a depiction of a portion of a spine. Algorithms map treatment settings from one level of abstraction to settings at one or more other levels of abstraction.

An electrosurgical system and method for ablating, resecting, or cutting body structures, with minimal or no damage to tissue adjacent to the treatment site. The system includes an electrosurgical probe having a shaft with a shaft distal end bifurcated to provide first and second arms. First and second electrode supports are disposed on the first and second arms, respectively. At least one active electrode, in the form of a loop or partial loop, is arranged between the first and second electrode supports. A return electrode, also in the form of a loop or partial loop, is arranged between the first and second electrode supports distal to the active electrode. The active and return electrodes are configured to promote substantially high electric field intensities and associated high current densities between the active portion and the target site when a high frequency voltage is applied to the electrodes. These high current densities are sufficient to break down the tissue by processes including molecular dissociation of tissue components. In one embodiment, the high frequency voltage imparts energy to the target site to effect the vaporization and volumetric removal of a layer of tissue without causing substantial tissue damage beyond the layer of tissue ablated. In another embodiment, a fragment of target tissue is removed, with minimal or no damage to surrounding tissue, by a process including the molecular dissociation of tissue components, and the tissue fragment is retrieved for biopsy.

A tilt-compensated electronic compass can be realized by calculating rather than measuring Earth's magnetic field component Z in a direction orthogonal to the two measurement axes of a 2-axis magnetic sensor. The orthogonal component Z can be calculated using a stored value for the Earth's magnetic field strength applicable over a wide geographic region. The calculation also requires using measured field values from the 2-axis sensor. Once Z is known, and using input from a 2-axis tilt sensor, compensated orthogonal components X and Y can be calculated by mathematically rotating the measured field strength values from a tilted 2-axis sensor back to the local horizontal plane. Thus, a very flat and compact tilt-compensated electronic compass is possible.

Vehicles (1-1) or ships (1-2) each carry a magnetic force line sensor (11), a GPS position detector (12), and a data transmitter (13) and travel within an observation area transmitting magnetic field data and position data of each point to an earthquake prediction center (4). A telluric current induction field estimation unit (43) of the earthquake prediction center (4) estimates telluric current induction fields based on the observation data that it receives and collects. A telluric current estimation unit (44) estimates telluric currents based on the results of estimating the telluric current induction fields. A telluric current induction field intensity change pattern generation unit (45) generates patterns that indicate the change over time of the intensity of telluric current induction fields. An earthquake prediction unit (46) analyzes the state of distribution of the telluric currents and the patterns of change in the intensities of the telluric current induction fields and estimates a seismofocal zone, seismic intensity, and time of occurrence of a seismic event.

PCT No. PCT / GB96 / 00823 Sec. 371 Date Jan. 12, 1998 Sec. 102(e) Date Jan. 12, 1998 PCT Filed Apr. 3, 1996 PCT Pub. No. WO96 / 31790 PCT Pub. Date Oct. 10, 1996Magnetic tags or markers are disclosed, together with a variety of techniques by means of which such tags may be interrogated. In one aspect, the magnetic marker or tag which is characterized by carrying a plurality of discrete magnetically active regions in a linear array. In another aspect, the invention provides a method of interrogating a magnetic tag or marker within a predetermined interrogation zone, the tag comprising a high permeability magnetic material, for example to read data stored magnetically in the tag or to use the response of the tag to detect its presence and / or to determine its position within the interrogation zone, characterized in that the interrogation process includes the step of subjecting the tag sequentially to: (1) a magnetic field sufficient in field strength to sacurate the high permeability magnetic material, and (2) a magnetic null as herein defined. Applications of such techniques are describer, inter alia, in relation to (a) identifying articles to which tags are attached; (b) accurate determination of position, as in the location of surgical probes; and (c) totalisation of purchases, where cash item carries a tag coded with data representing its nature and its price.

It is an objective to achieve a MEMS switch which can be mounted with a CMOS circuit and has a contact point with high reliability, both mechanically and electrically. An insulator having a compatibility with a CMOS process is formed at the contact surface of a cantilever beam constituting a MEMS switch and a fixed contact 2 opposite thereto. When the switch is used the cantilever beam is moved by applying a voltage to the pull-in electrode and the cantilever beam. After the cantilever beam makes contact with the fixed contact, a voltage exceeding the breakdown field strength of the insulator is applied to the insulator, resulting in dielectric breakdown occurring. By modifying the insulator once, the mechanical fatigue concentration point of the switch contact point is protected, and a contact point is achieved as well in which electrical signals are transmitted through the current path formed by the dielectric breakdown.

Systems and methods for automatically triggering wireless power and data exchange between an external reader and an implanted sensor. The implanted sensor may measure the strength of an electrodynamic field received wirelessly from the reader and convey field strength data based on the measured strength of the received electrodynamic field to the reader. If the field strength data indicates that the strength of an electrodynamic field received by the sensor is sufficient for the implanted sensor to perform an analyte measurement, the reader may convey an analyte measurement command to the sensor, which may execute the analyte measurement command and convey measurement information back to the reader. The systems and methods may trigger the analyte measurement as the reader transiently passes within sufficient range / proximity to the implant (or vice versa).

A main control portion of a vehicle has an LF transmission antenna for transmitting a search signal. The LF transmission antenna has five antennas respectively provided on door knobs of the vehicle. A smart key receives the search signals transmitted from respective antennas constituting the LF transmission antenna, and then measures a filed strength of the received search signal. The smart key transmits field strength information representing the measured field strength to the main control portion. The main control portion calculates relative position information of the vehicle to the smart key, based on the field strength information. On the basis of the relative position information, the main control portion controls the door of the vehicle to be locked or unlocked.

A main control portion of a vehicle has an LF transmission antenna for transmitting a search signal. The LF transmission antenna has five antennas respectively provided on door knobs of the vehicle. A smart key receives the search signals transmitted from respective antennas constituting the LF transmission antenna, and then measures a filed strength of the received search signal. The smart key transmits field strength information representing the measured field strength to the main control portion. The main control portion calculates relative position information of the vehicle to the smart key, based on the field strength information. On the basis of the relative position information, the main control portion controls the door of the vehicle to be locked or unlocked.

A strut (12) is configured for an active suspension system (142) which provides electronic control for both the force applied by the strut (12) and the dampening characteristics of the strut (12). A compressible fluid (18) is used within the strut (12), and preferably includes a compressible base fluid and electromagnetic field responsive particles (132) which are suspended in the compressible base fluid. The electromagnetic field responsive particles (132) are preferably closely matched in density and modulas of elasticity to that of the compressible base fluid to prevent sedimentation of the particles (132) and to maintain the elasticity of the compressible fluid (18). The amount compressible fluid (18) within the strut (12) is electronically controlled to determine the force applied by the strut (12) and a field strength applied to the compressible fluid in a fluid flow passage is electronically controlled to determine the dampening characteristics of the strut (12).

A personal alarm system includes a monitoring base station and one or more remote sensing units in two-way radio communication. An electronic handshake between the base station and each remote unit is used to assure system reliability. The remote units transmit at selectable power levels. In the absence of an emergency, a remote unit transmits at a power-conserving low power level. Received field strength is measured to determine whether a remote unit has moved beyond a predetermined distance from the base station. If the distance is exceeded, the remote unit transmits at a higher power level. The remote unit includes sensors for common hazards including water emersion, smoke, excessive heat, excessive carbon monoxide concentration, and electrical shock. The base station periodically polls the remote units and displays the status of the environmental sensors. The system is useful in child monitoring, for use with invalids, and with employees involved in activities which expose them to environmental risk. Alternative embodiments include a panic button on the remote unit for summoning help, and an audible beacon on the remote unit which can be activated from the base station and useful for locating strayed children. In another embodiment, the remote unit includes a Global Positioning System receiver providing location information for display by the base station.

As compared to conventional electrodes, the electrode configurations disclosed herein minimize irritation and damage to the skin when they are placed in contact with a patient's body over extended of time. The electrodes are formed from a conductive substrate coated with a thin dielectric material, and a plurality of open spaces pass through the electrodes. Those open spaces are distributed and sized to permit moisture on the surface of the patient's body to escape when the electrode is placed in contact with the patient's body. One intended use for the electrodes is for treating tumors by applying an AC electric field with specific frequency and field strength characteristics over an extended period of time.

When a personal computer which implements an information processing apparatus according to this invention discovers communicable access points, the personal computer acquires pieces of information of the discovered access points. These pieces of information include, for example, the network name, communication speed, security level, communication channel, and radio field strength. A communication profile to be used by the personal computer is determined on the basis of these pieces of information, communication profiles set for the access points, and the priority of a communication profile to be used by the personal computer. A connection process between the personal computer and a wireless relay apparatus is automatically performed using the determined communication profile.

An apparatus and method for applying pulsed electromagnetic therapy to humans and animals. A straight wire element is employed to generate the magnetic field. A power and timer circuit supplies current pulses that approximate square pulses in form, so that the straight wire element generates magnetic pulses having rapid rise and fall times. Peak field strength is approximately 2 gauss at a 1 cm distance from the straight wire element, and the duration of peak field strength is approximately 200 nanoseconds. The pulses are repeated at a frequency of about 70 Hz. The straight wire element and circuit may be housed in a hand-held probe, with an LED illuminating the skin area to provide a visual indication of effective range, or a plurality of the straight wire elements and associated circuits may be embedded in a conformable pad that is placed over the affected area of the body.

The invention relates to a travelling risk field-based automobile driving safety assistance method which comprises the steps of (1) establishing a travelling risk field unified model according to the combined action of all factors of people, automobiles and roads in the ambient environment for the travelling risk; (2) establishing a self automobile travelling risk field model by building a mathematical model of the kinetic energy field, the potential energy field and the behavior field of objects in the ambient environment, and calculating the total field intensity of the travelling risk field of a self automobile; (3) calculating the acting force applied to the self automobile in the travelling risk field based on the total field intensity of the travelling risk field; (4) calculating the travelling risk factor of the self automobile according to the acting force applied to the self automobile in the travelling risk field, and carrying out safety assistance in the travelling process based on the risk factor. The method is suitable for decision of driving safety assistance in the complex environment and the route planning of an intelligent vehicle.

An assembly for detecting radiation is described. The assembly includes a host matrix with particles suspended within the host matrix. The particles are capable of generating a charge carrier upon interaction with the radiation. A first electrode is disposed adjacent to a first surface of the host matrix, and a second electrode disposed adjacent to a second surface of the host matrix. A power source operatively connects to one of the first or second electrodes. The power source establishes an electric field between the first and second electrodes such that a ratio of a mobility-lifetime-field strength product of the charge carrier to the thickness of the host matrix is greater than or equal to 0.1. A radiation detector and a method for detecting radiation are also described.