Abstract: A coil for receiving a magnetic resonance signal is provided. The coil may include a first conductor; and a second conductor electrically coupled to the first conductor. The second conductor may extend along the first conductor. The first conductor may have at least one first opening or the second conductor may have at least one second opening. The first conductor and the second conductor may be electrically coupled using an electronic component placed at the at least one first opening or the at least one second opening so that an electric current flows between the first conductor and the second conductor through the electronic component.

Abstract: Wireless power transmittal apparatus and systems are disclosed in which transmitter and receiver inductors, or coils, are coupled in configurations for wirelessly transferring power and/or data among them. In preferred implementations, a plurality of non-coplanar primary side coils are provided in power transmittal apparatus for transmitting power, or power and data.

Abstract: Various methods and systems are provided for radio frequency (RF) coils for magnetic resonance imaging (MRI). In one embodiment, a radio frequency coil assembly for a magnetic resonance imaging system includes: a flexible spine; and at least two RF coil sections each coupled to the flexible spine and movable relative to each other, each RF coil section comprising at least one flexible RF coil, each RF coil including a loop portion comprising a coupling electronics portion and at least two parallel, distributed capacitance wire conductors encapsulated and separated by a dielectric material.

Abstract: A position sensor includes a flexible substrate formed into a three-dimensional (3D) shape. At least first and second field-sensing coils are formed in first and second respective layers of the flexible substrate, such that in the 3D shape the first and second field-sensing coils have first and second respective axes that are not parallel to one another.

Abstract: According to some aspects, a magnetic resonance imaging system capable of imaging a patient is provided. The magnetic resonance imaging system comprising at least one B0 magnet to produce a magnetic field to contribute to a B0 magnetic field for the magnetic resonance imaging system and a member configured to engage with a releasable securing mechanism of a radio frequency coil apparatus, the member attached to the magnetic resonance imaging system at a location so that, when the member is engaged with the releasable securing mechanism of the radio frequency coil apparatus, the radio frequency coil apparatus is secured to the magnetic resonance imaging system substantially within an imaging region of the magnetic resonance imaging system.

Abstract: A sensor probe. The probe includes a central loop and a plurality of peripheral loops disposed peripherally relative to the central loop. To maximize far-field suppression, current flows in a first direction through the central loop and in a second direction through each one of the plurality of peripheral loops, the first direction opposite to the second direction, and current through the central loop equals current through the plurality of peripheral loops.

Abstract: A magnetic resonance device (1), having a main magnet unit (2) with a cylindrical patient aperture (3), wherein at least one radial gradient coil (9) is provided in the patient aperture (3) which generates a gradient field having, at least in regions, a radial gradient in relation to its own central axis parallel to the longitudinal axis of the patient aperture (3), the radial gradient coil (9) being embodied as a cylinder coil.

Abstract: A maneuverable RF coil assembly, useful for being maneuvered at both positions: (i) over at least a portion of a neonate immobilized within a cradle at time of MR imaging; and (ii) below or aside the cradle when it is not required for imaging. The maneuverable RF coil assembly comprises at least one RF coil and maneuvering mechanism. The maneuvering mechanism comprises both: (i) a linear reciprocating mechanism for approaching or otherwise drawing away at least one coil to and from the neonate; and (ii) tilting mechanism for placing at least one coil away from the neonate.

Abstract: Various methods and systems are provided for radio frequency (RF) coils for magnetic resonance imaging (MRI). In one embodiment, an RF coil assembly for an MRI system includes a posterior end including a first set of flexible RF coils; an anterior end including a second set of flexible RF coils; a central section extending between the posterior end and anterior end, wherein the posterior end and the anterior end are bendable to the central section. Each flexible RF coil of the first set and second set of flexible RF coils includes a loop portion comprising a coupling electronics portion and at least two parallel, distributed capacitance wire conductors encapsulated and separated by a dielectric material.

Abstract: Systems, methods, and an apparatus for current monitoring are disclosed. A current monitor comprises a high-voltage side configured to obtain a signal indicative of current through a conductor and apply different levels of gain to different frequency bands of the signal to produce an adjusted signal. A low-voltage side of the current monitor is electrically isolated from the high-voltage side and is configured to split the adjusted signal to produce a plurality of output signals that are each indicative of a level of current at one of the different frequency bands. An isolation amplifier is configured to communicate the adjusted signal from the high-voltage side to the low-voltage side while electrically isolating the high-voltage side from the low-voltage side.

Abstract: Systems and methods for obtaining simultaneous X-ray-magnetic resonance imaging (MRI) images are provided. A magnetic resonance X-ray CT (MRX) system can combine X-ray imaging and MRI in a cost-effective and relatively simple solution for improved imaging. During imaging of a subject, the X-ray source and X-ray detector can be simultaneously rotated around the subject, and the means for generating a magnetic field can also be rotated around the subject. The means for generating a magnetic field can be a plurality of permanent magnets.

Abstract: A birdcage coil for a magnetic resonance imaging (MRI) system, the birdcage coil includes: a relatively planar birdcage coil section, including a pair of relatively planar ring portions and a plurality of conductive, elongated rungs extending between the pair of relatively planar ring portions; and a relatively domed birdcage coil section, including a pair of relatively domed ring portions and a plurality of conductive, elongated rungs extending between the pair of relatively domed ring portions. The relatively domed birdcage coil section is releasably coupled to the relatively planar birdcage coil section. In an embodiment, at least two sets of the relatively planar and domed birdcage coil sections are provided, where each of the at least two sets is configured to a different MRI application.

Abstract: A basic field magnet arrangement for a magnetic resonance tomography system can include a plurality of basic field magnet segments spatially separated from one another, each being configured to generate an intended magnetic field having a defined segment main field direction. At least two basic magnet segments of the plurality of the basic field magnet segments are arranged relative to one another such that the respective segment main field directions of their intended magnetic fields extend at a deflection angle to one another such that the intended magnetic fields of the at least two basic field magnet segments produce an intended basic magnetic field. The intended basic magnetic field including a basic magnet main field direction can have a ring-shaped profile.

Abstract: A magnetic resonance (MR) imaging system includes: a main magnet configured to generate a volume of magnet field suitable for forming MR imaging; a transmit radio frequency (RF) coil assembly configured to transmit at least one RF signal; a receive radio frequency (RF) coil assembly configured to, in response to the at least one RF pulse, receive MR signals; a gradient coil assembly comprising (i) windings of coils arranged in a radial layer, and (ii) a first set of connectors embedded in the radial layer to reduce a radial extent occupied by the gradient coil assembly, the first set of electrical connectors configured to drive the windings of coils; and a control unit coupled to the transmit RF coil assembly, the receive RF coil assembly, and the gradient coils, the control unit configured to synchronously operate the gradient coil assembly, the transmit coil assembly, and the receive coil assembly.

Abstract: Embodiments relate to MRI coils and arrays comprising an all-in-one circuit that can perform all the functions of decoupling, balun, tuning, and preamplifier decoupling. One example embodiment is a magnetic resonance imaging (MRI) radio frequency (RF) coil element, comprising: a coil comprising at least one inductor, at least one capacitor, and two connection points; a lattice balun comprising two inputs and two outputs, wherein the two inputs of the lattice balun are connected across the two connection points of the coil; one or more shunt reactive elements connected across the two outputs of the lattice balun, wherein the one or more shunt reactive elements comprises at least one of one or more shunt capacitors or one or more shunt inductors; one or more protection diodes in parallel with the one or more shunt reactive elements; and a low input impedance preamplifier in parallel with the one or more protection diodes.

Abstract: Techniques are disclosed for acquiring magnetic resonance data of an object with a magnetic resonance imaging apparatus. A slice group is imaged whose slices define a contiguous imaging volume and which contains a first number of slices. In a number of concatenations, the magnetic resonance data for subgroups of the slices, each containing a respective second number of slices depending on the first number of concatenations, are acquired, and shimming is performed to increase field homogeneity in the imaging volume. To define the subgroups, the imaging volume is subdivided into at least two disjoint contiguous sub-volumes, and at least two subgroups are defined for each sub-volume, each subgroup only containing non-adjacent slices in the sub-volume. During acquisition of the magnetic resonance data of each subgroup, shimming is at least restricted to the respective sub-volume.

Abstract: According to one embodiment, a magnetic resonance imaging apparatus includes processing circuitry. The processing circuitry is configured to apply a filter to each of a first real-part image and a first imaginary-part image of a first complex image generated based on acquired magnetic resonance data and thereby generate a second complex image that includes a second real-part image and a second imaginary-part image. The processing circuitry is configured to generate a phase image denoised by the filter, the denoised phase image generated based on the second real-part image and the second imaginary-part image. The processing circuitry is configured to generate an intensity image related to an absolute value of the first complex image based on pixel values of the denoised phase image, the first real-part image, and the first imaginary-part image.

Abstract: The invention relates to a gradient shield coil (5) for a MRI apparatus (1). The gradient shield coil (5) according to the invention comprises windings (6, 7) around its longitudinal axis (A), wherein at least one winding (7) is arranged as a meandering winding (7). This meandering winding (7) comprises multiple contiguous sections (8) along its circumference, wherein in each of these sections (8) a pair of conductor loops (9, 10) is provided in such a way that a current in the meandering winding (7) would run in opposite directions in the two conductor loops (9, 10). In this way, dissipation in the superconductive coils of a superconductive magnet (2) of a respective MRI apparatus (1) may be further reduced.

Abstract: The present invention relates to an RF transmit system and method, MRI system and a pre-scan method and medium thereof. The RF transmit system comprises: an RF output unit, for generating and outputting an RF pulse signal; an RF amplifier, for amplifying the RF pulse signal; and a signal processing unit, for communicating the amplified RF pulse signal to an RF transmit coil of the MRI system and outputting a feedback signal to the RF output unit, wherein the RF output unit generates a linearity compensation control signal based on the feedback signal and a predetermined feedback signal-linearity compensation value-relationship, so as to carry out linearity compensation for the RF pulse signal outputted by the RF output unit. The RF transmit method corresponds to the above noted system and the MRI system comprises the above noted RF transmit system. The pre-scan method comprises the RF transmit method. Instructions recorded by the medium may execute the above noted RF transmit method and pre-scan method.

Abstract: An asymmetric electromagnet system, method, and method of producing an asymmetric electromagnet system, wherein the asymmetric electromagnet system is for generating an imaging magnetic field in an imaging region with an imaging isocentre, the imaging region being asymmetrically positioned within a gradient coil bore inside a magnetic resonance imaging (MRI) system during imaging, the electromagnet assembly comprising: an asymmetric gradient coil configured to generate a gradient field in the asymmetrically positioned imaging region, at least one gradient axis having the gradient field with a constant offset component such that the position at which the gradient field passes through zero is offset with respect to the imaging isocentre of the asymmetrically positioned imaging region.

Abstract: The disclosure relates to a field camera and a method for measuring a magnetic field distribution using a magnetic resonance tomograph and the field camera. The field camera has a number of samples, which are distributed over a spatial volume to be measured, and a number of receive antennas. In an act of the method, a sensitivity matrix for the receive antennas, for each sample at each receive antenna, is captured using the magnetic resonance tomograph. In another act, antenna signals of the samples in a magnetic field to be measured are captured by the receive antennas, using the magnetic resonance tomograph. Finally, magnetic resonance signals of the individual samples are determined from the antenna signals as a function of the sensitivity matrix, using a controller. In a further act, the magnetic field strength at the location of the samples may be determined from the magnetic resonance signals.

Abstract: A device to estimate mechanical properties of brain and abdomen organs undergoing magnetic resonance elastography (MRE) includes electromagnetic actuators, mechanical wave generation mechanisms, and a control unit to generate oscillatory motion signals in synchronization with the MR scanner. Preserving only the shear wave component, a local fitting algorithm is used to estimate the viscoelastic properties of soft tissues. The device is portable and easy to implement in clinical diagnostics, and can be modified to measure other soft materials.

Abstract: A method for operating a magnetic resonance imaging (MRI) system that includes: accessing data indicating a first region for imaging a portion of a subject, the portion being placed in a main magnet of the MRI system and the main magnet generating a magnetic field; selecting, from a group of available shimming coils, a first subset of shimming coils arranged and configured such that, when the shimming coils in the first subset are driven, a homogeneity of the magnetic field at the first region is increased; and driving the shimming coils in the selected first subset of shimming coils without driving other shimming coils in the group of available shimming coils such that the homogeneity of the magnetic field at the first region increases relative to the homogeneity of the magnetic field at the first region when the shimming coils of the selected first subset are not driven.

Abstract: A system for positioning of an RF surface coil to several imaging tables has a table coupling device with first and second sides and table engagement features. The first side has a planar surface to mate with a first imaging table. The second side has a contoured surface having a curvature to mate with a second imaging table. A coil coupling device selectively couples to each of the first and second sides of the table coupling device in respective first and second configurations. The coil coupling device selectively rotates about a rotation axis perpendicular to the first side, and selectively translates along a translation axis perpendicular to the rotation axis. The coil coupling device has one or more coil engagement features to selectively engage the RF surface coil in each of a horizontal position and vertical position of the RF surface coil with respect to the table coupling device.

Abstract: According to some aspects, an apparatus is provided comprising a deployable guard device, configured to be coupled to a portable medical imaging device, the deployable guard device further configured to, when deployed, inhibit encroachment within a physical boundary with respect to the portable medical imaging device. According to some aspects, an apparatus is provided comprising a deployable guard device, configured to be coupled to a portable magnetic resonance imaging system, the deployable guard device further configured to, when deployed, demarcate a boundary within which a magnetic field strength of a magnetic field generated by the portable magnetic resonance imaging system equals or exceeds a given threshold.

Abstract: Provided is an NMR arrangement, including an NMR device, a storage system for storing sample tubes, and a transport system for transporting the sample tubes from the storage system to the NMR device and from the NMR device to the storage system. The storage system is mechanically decoupled from the NMR device. Furthermore, the transport system includes a first guiding element that is mechanically coupled to the storage system; a second guiding element that is mechanically coupled to the NMR device; and a sample tube carrier that can be moved between the first guiding element and the second guiding element so as to transport the sample tubes from the storage system to the NMR device and from the NMR device to the storage.

Abstract: Artifacts caused by metallic needles used in MRI-guided procedures such as tumor biopsies significantly decrease the visibility of therapy targets and diminish the ability of the physician to accurately monitor and perform the procedure. As described in the present application, a needle including active shimming can self-compensate for these artifacts and significantly improve the visualization and monitoring of targeted tissue. The accuracy and overall outcomes of MRI-guided treatments can be significantly improved with the use of the needle.

Abstract: The invention provides for a magnetic resonance imaging system (100) comprising a main magnet (104) for generating a main magnetic field within an imaging zone (108). The magnetic resonance imaging system further comprises an RF coil (114) for acquiring magnetic resonance data (164) from the imaging zone, wherein the RF coil comprises multiple RF ports (124, 412, 414, 416, 500, 502, 702, 1004, 1006). The RF coil comprises a switch unit (120) for at least one of the multiple RF ports to individually couple or uncouple the at least one of of the multiple RF ports from the RF coil. The magnetic resonance imaging system further comprises a radio-frequency system (125) for supplying radio-frequency power to each of the multiple RF ports and an RF matching detection system (122) for measuring impedance matching data (166) between the radio-frequency system and the RF coil.

Abstract: A pediatric magnetic resonance imaging (MRI) system is provided. The pediatric MRI system includes a radio frequency (RF) coil configured to image a portion of a patient. The pediatric MRI system also includes a cryo-cooling mechanism operatively coupled to the RF coil. The cryo-cooling mechanism is configured to maintain a temperature of the RF coil within a prescribed temperature range.

Abstract: An electrical meter (M) installed at a facility (F) supplied electrical power by a utility's (U) electrical distribution system (EDS) utilizes a two-way automatic communications system (TWACS) for receiving messages from the utility sent over the electrical distribution system using the TWACS. An improvement to the meter comprises reconfiguring existing components installed in the meter to function as an analog-to-digital (ADC) converter so to facilitate processing of powerline waveforms (WF) propagated through the electrical distribution system by application of a signal based detection algorithm. This improves detection of signal elements comprising a message sent via the TWACS and by other means and incorporated in the electrical waveforms thereby reducing occurrence of a false synchronization with the message elements so a content of a message is readily ascertained by the meter.

Abstract: A method for generating an image data set of an image area located in a measurement volume of a magnetic resonance system comprising a gradient system and an RF transmission/reception system, comprises the following method steps: —reading out k-space corresponding to the imaging area, by: (a) activating a frequency encoding gradient in a predetermined spatial direction and with a predetermined strength G0 by means of said gradient system, (b) after the activated frequency encoding gradient achieves its strength G0, radiating a non-slice-selective RF excitation pulse by means of said RF transmission/reception system, (c) after a transmit-receive switch time ?tTR following the radiated excitation pulse, acquiring FID signals with said RF transmission/reception system and storing said FID signals as raw data points in k-space along a radial k-space trajectory that is predetermined by the direction and strength G0 of the frequency encoding gradient, (d) repeating (a) through (c) with respectively different freque

Abstract: A system includes a magnetic resonance gradient accessory within an MRI system. The MRI system includes a magnet housing, a superconducting magnet generating a magnet field B0 to which a patient is subjected, shim coils, RF coils, receiver coils, magnetic gradient coils, and a patient table. The magnetic resonance gradient accessory creates local magnetic gradient fields critical to image generation and provides for diffusion encoding of a specific body region.

Abstract: An apparatus and method for dynamically stabilizing the fields in a permanent magnet assembly, including a nuclear magnetic resonance machine. One or more magnetically active elements affect the fields of the magnet assembly. A mechanism controls and changes the position(s) of the magnetically active element(s) to affect and adjust the magnetic field strength in the working volume of the assembly. A sensor provides a control signal indicating the status of the magnetic field strength, and an algorithm is executed for determining, based on the signal, the manner in which the adjustment should be made. The adjustment may be continuous and dynamic, and stabilization of the field may occur during operation of the permanent magnet assembly. The adjustments of the position of the magnetically active element stabilize the field without unduly degrading the field homogeneity, even for high homogeneity magnets.

Abstract: A method for producing a measurement value transmitter for a sensor device includes providing a magnetic body, providing a coil configured to be supplied with a current, and shaping the coil into a helical winding with an internal diameter that is greater than an outer contour of the magnetic body. The winding is shaped such that the pitch of the winding changes at least in some sections when viewed along the longitudinal extension of the winding. The method further includes arranging the magnetic body within the coil, in particular coaxially to the coil, and supplying the coil with a current so as to magnetize the magnetic body in order to produce the measurement value transmitter.

Abstract: Embodiments relate to cylindrical MRI coils with at least one row as a birdcage row in a transmit mode. One example embodiment is a MRI Radio Frequency (RF) coil array comprising two or more rows of four or more RF coil elements each. Each of the RF coil elements can be configured to resonate at a working frequency of the coil array in a receive mode. At least one of the rows can be configured as a birdcage coil in the transmit mode, and the two or more rows can inductively couple together such that all the two or more rows can resonate together in the transmit mode at the working frequency.

Abstract: A method for designing gradient coils includes the following steps: a) defining an imaging volume as an ellipsoid; b) defining an elliptic-cylindrical surface enclosing the said ellipsoid; c) defining the current density at each point of the surface by a series of basis functions and corresponding coefficients expressed in elliptic cylindrical coordinates; d) describing the magnetic field generated at a generic point by the above defined current density integrated all over the said entire elliptic-cylindrical surface; e) determining the values of the coefficients of the basis functions by solving the inverse function for describing the magnetic field; f) generating a discrete winding patter of a gradient coil by using a stream function method from the continuous current density and by using a series of scattered contours of the stream function as the design of the winding patters according to a set total number of windings.

Abstract: A high-frequency array coil for an MRI apparatus includes: a plurality of coil units each of which includes a plurality of RF reception coils including a conductor loop and adjusted to receive a magnetic resonance signal; an extension conductor which includes a part of each conductor loop of each RF reception coil of the plurality of coil units and a conductor connecting the parts; and an extension conductor control circuit which adjusts a reception frequency of the extension conductor. The extension conductor is disposed so as to be wound in a spiral shape when the extension conductor is disposed on a subject and a direction of a magnetic field to be detected intersects a direction of a magnetic field detected by the RF reception coil constituting the coil unit. Accordingly, the detection efficiency of an RF coil can be increased and an image with a high SNR can be obtained.

Abstract: Described herein are database systems including one or more remote analytical instruments operably connected to one or more servers. The instruments can transmit rich data to the servers, and the one or more servers can compile a database of the rich data. One or more processors associated with the servers can be configured to execute a data analytics program on the database to identify a stochastic phenomenon or to process the data and present in real-time at a location of the one or more instruments comparison information about the instruments.

Abstract: A flexible RF coil with excellent portability is provided. The RF coil includes a first coil, a first skeleton, and a second skeleton, the first skeleton and the second skeleton being rod shaped. The first coil includes a first loop made from a conductor that receives radio frequency signals, and a first signal detector that is inserted in series into the first loop and that detects the signals received by the first loop. The first skeleton and the second skeleton are arranged with a spacing in the short axis direction, the first signal detector is mounted on the first skeleton, and a portion of the first loop that faces the first signal detector is mounted on the second skeleton. The first loop is deformable, and the spacing between the first skeleton and the second skeleton is changeable in accordance with the deformation of the first loop.

Abstract: According to one embodiment, a medical image diagnostic apparatus includes a gantry, a couch, a movable base, a screen, a reflecting plate, and a support body. The gantry has a bore formed therein and performs medical imaging. The couch is configured to move the table top along the central axis of the bore. The movable base is provided independently of the table top so as to be movable along the central axis of the bore. The screen is provided on the movable base. An image from a projector is projected on the screen. The reflecting plate reflects the image projected on the screen. The support body is provided on the movable base and supports the reflecting plate.

Abstract: A gradient coil assembly for a magnetic resonant apparatus has a primary coil and a secondary coil, wherein the primary coil has a first primary coil winding and a second primary coil winding, wherein the first primary coil winding and the second primary coil winding are electrically connected to a voltage source and are jointly designed to generate a magnetic field gradient in a direction when the voltage source induces a current in those windings.

Abstract: The NMR probe head comprises a base and a tube. A coil is arranged in the tube. A tuning and matching circuit is also arranged in the tube adjacent to the coil. The coil and/or the tuning and matching circuit comprise several tunable elements. Several actuators are arranged in the tube for actuating the tunable elements. The actuators are located in in a compact actuator assembly.

Abstract: A magnetic resonance imaging (MRI) radio frequency (RF) coil array configured to operate in a transmit (Tx) mode or in a receive (Rx) mode, comprising: a plurality of rows configured in an anatomy-specific shape, a row including a plurality of RF coil elements, an RF coil element including an LC coil and a magnitude/phase control component, where the LC coil, upon resonating with a primary coil at the working frequency of the primary coil, generates a local amplified Tx field based on an induced current in the LC coil, where a magnitude or a phase of the induced current is independently adjustable, where the magnitude/phase control component is configured to adjust the magnitude or phase of the induced current, and where the magnitude or phase of the induced current of a first RF coil element is independently adjustable from that of a second, different RF coil element.

Abstract: An apparatus for controlling at least one gradient coil of a magnetic resonance imaging (MRI) system. The apparatus may include at least one computer hardware processor; and at least one computer-readable storage medium storing processor executable instructions that, when executed by the at least one computer hardware processor, cause the at least one computer hardware processor to perform a method. The method may include receiving information specifying at least one target pulse sequence; determining a corrected pulse sequence to control the at least one gradient coil based on the at least one target pulse sequence and a hysteresis model of induced magnetization in the MRI system caused by operation of the at least one gradient coil; and controlling, using the corrected gradient pulse sequence, the at least one gradient coil to generate one or more gradient pulses for imaging a patient.

Abstract: This disclosure provides a method of measuring the axial rotation of a selected vertebra of a patient using a magnetic resonance (MR) image. The method includes: identifying, in the MR image, two or more features of the selected vertebra; determining a first axis connecting the identified features; identifying, in the MR image, two or more features of the patient's surrounding anatomy that are not features of the selected vertebra; determining a second axis connecting the identified features of the patient's surrounding anatomy; measuring the angular difference between the first and second axes; and determining the axial rotation of the cervical vertebra based on the measurement. In some examples of the disclosure, determining the axial rotation of the cervical vertebra is based on the degree of perpendicularity between the first and second axes.

Abstract: Example embodiments of the present invention provide a magnetic relaxometry measurement apparatus, comprising: a magnetizing system configured to supply a pulsed magnetic fields to a sample; a sensor system configured to detect magnetic fields produced by induced magnetization of the sample after a magnetic field pulse from the magnetizing system; one or more compensating coils configured to suppress generation of eddy currents in an environment surrounding the apparatus due to the pulsed magnetic fields.

Abstract: An RF antenna element with a detuning system in which the RF antenna element comprises a resonant electrically conductive loop. The (de)tuning system comprising a switching element to (de)tune the resonant electrically conductive loop. The (de)tuning system element includes an electroluminescent element coupled to the resonant electrically conductive loop. The (de)tuning system includes a photo-electrical conversion element to detect an electro-luminescent signal from the electroluminescent element.

Abstract: A calibration method for calibrating a measuring element for determining an electric current flowing through a basic-field magnet of a magnetic resonance imaging system includes performing a measurement with the measuring element, and performing a frequency measurement in the magnetic field of the basic-field magnet with a frequency measuring unit. The measurement of the measuring element and the frequency measurement are corresponding to the same magnetic field of the basic-field magnet. The calibration method also includes calculating a calibration factor based on a deviation between the measurement with the measuring element and the frequency measurement, and calibrating the measuring element or the electric current in the basic-field magnet based on the calibration factor.

Abstract: An apparatus, method, and system are disclosed for improving uniformity of RF magnetic field in an MRI system, and thereby improving both signal-to-noise ratio and uniformity of imaging sensitivity across a sampling volume, to provide more uniform MRI images. A passive LC resonator develops induced EMF and induced currents in a primary RF magnetic field; the secondary magnetic field produced thereby can counteract magnetic field amplitude gradients to produce a more homogeneous RF magnetic field. In systems with separate transmit and receive coils, a shunt detuning circuit is pulsed ON to prevent interference during the transmit period. In a dual-frequency MRI machine (e.g. 19F and 1H), the RF magnetic field at the lower operating frequency can be homogenized by tuning the resonance of the passive resonator between the two operating frequencies. Another resonator can improve RF field uniformity at the higher operating frequency. Variants and experimental results are disclosed.

Abstract: In one embodiment of a wireless power transmitter, two coils are magnetically coupled together by placing both coils on a magnetic layer. A power circuit generates an AC signal of a defined voltage magnitude that causes a current to flow through the first coil, which generates a magnetic field having a first polarity. The second coil is coupled to the first coil. Current flows through the second coil and generates a magnetic field having a second polarity that is opposite from the first polarity. Because the magnetic field generated by each coil has a different polarity, the magnetic fields attract and form a strong magnetic field that flows from the first coil to the second coil. The strong magnetic field can transfer greater amounts of power to a receiver in comparison to coil configurations that emit magnetic fields in the same direction that repel one another.