Arrangements or instruments for measuring magnetic variables

GPHYSICS G01Measuring instruments G01RMEASURING ELECTRIC VARIABLES MEASURING MAGNETIC VARIABLES

G01R33/00Arrangements or instruments for measuring magnetic variables

G01R33/0005Geometrical arrangement of magnetic sensor elements; Apparatus combining different magnetic sensor types G01R33/0011comprising means G01R33/0017Means for compensating offset magnetic fields or the magnetic flux to be measured; Means for generating calibration magnetic fields G01R33/0023Electronic aspects G01R33/0029Treating the measured signals G01R33/0035Calibration of single magnetic sensors G01R33/0041using feed-back or modulation techniques G01R33/0047Housings or packaging of magnetic sensors ; Holders G01R33/0052Manufacturing aspects; Manufacturing of single devices G01R33/0058using bistable elements G01R33/0064comprising means for performing simulations G01R33/007Environmental aspects G01R33/0076Protection G01R33/0082Compensation G01R33/0088use of bistable or switching devices G01R33/0094Sensor arrays G01R33/02Measuring direction or magnitude of magnetic fields or magnetic flux G01R33/0206Three-component magnetometers G01R33/0213using deviation of charged particles by the magnetic field G01R33/022Measuring gradient G01R33/025Compensating stray fields G01R33/028Electrodynamic magnetometers G01R33/0283in which a current or voltage is generated due to relative movement of conductor and magnetic field G01R33/0286comprising micro-electromechanical systems [MEMS] G01R33/032using magneto-optic devices G01R33/0322using the Faraday or Voigt effect G01R33/0325using the Kerr effect G01R33/0327with application of magnetostriction G01R33/035using superconductive devices G01R33/0352Superconductive magneto-resistances G01R33/0354SQUIDS G01R33/0356with flux feedback G01R33/0358coupling the flux to the SQUID G01R33/038using permanent magnets G01R33/0385in relation with magnetic force measurements G01R33/04using the flux-gate principle G01R33/045in single-, or multi-aperture elements G01R33/05in thin-film element G01R33/06using galvano-magnetic devices G01R33/063Magneto-impedance sensors; Nanocristallin sensors G01R33/066field-effect magnetic sensors G01R33/07Hall effect devices G01R33/072Constructional adaptation of the sensor to specific applications G01R33/075Hall devices configured for spinning current measurements G01R33/077Vertical Hall-effect devices G01R33/09Magnetoresistive devices G01R33/091Constructional adaptation of the sensor to specific applications G01R33/093using multilayer structures G01R33/095extraordinary magnetoresistance sensors G01R33/096anisotropic magnetoresistance sensors G01R33/098comprising tunnel junctions G01R33/10Plotting field distribution; Measuring field distribution G01R33/12Measuring magnetic properties of articles or specimens of solids or fluids G01R33/1207Testing individual magnetic storage devices G01R33/1215Measuring magnetisation; Particular magnetometers therefor G01R33/1223Measuring permeability G01R33/123Measuring loss due to hysteresis G01R33/1238Measuring super-conductive properties G01R33/1246Measuring critical current G01R33/1253Measuring galvano-magnetic properties G01R33/1261using levitation techniques G01R33/1269of molecules labeled with magnetic beads G01R33/1276of magnetic particles G01R33/1284Spin resolved measurements; Influencing spins during measurements G01R33/1292Measuring domain wall position or domain wall motion G01R33/14Measuring or plotting hysteresis curves G01R33/16Measuring susceptibility G01R33/18Measuring magnetostrictive properties G01R33/20involving magnetic resonance G01R33/24for measuring direction or magnitude of magnetic fields or magnetic flux G01R33/243Spatial mapping of the polarizing magnetic field G01R33/246Spatial mapping of the RF magnetic field B1 G01R33/26using optical pumping G01R33/28Details of apparatus provided for in groups G01R33/44 - G01R33/64 G01R33/281Means for the use of in vitro contrast agents G01R33/282Means specially adapted for hyperpolarisation or for hyperpolarised contrast agents G01R33/283Intercom or optical viewing arrangements, structurally associated with NMR apparatus G01R33/285Invasive instruments G01R33/286involving passive visualization of interventional instruments G01R33/287involving active visualization of interventional instruments G01R33/288Provisions within MR facilities for enhancing safety during MR G01R33/30Sample handling arrangements G01R33/302Miniaturized sample handling arrangements for sampling small quantities G01R33/305specially adapted for high-pressure applications G01R33/307specially adapted for moving the sample relative to the MR system G01R33/31Temperature control thereof G01R33/32Excitation or detection systems G01R33/323Detection of MR without the use of RF or microwaves G01R33/326involving a SQUID G01R33/34Constructional details G01R33/34007Manufacture of RF coils G01R33/34015Temperature-controlled RF coils G01R33/34023Superconducting RF coils G01R33/3403Means for cooling of the RF coils G01R33/34038Loopless coils G01R33/34046Volume type coils G01R33/34053Solenoid coils; Toroidal coils G01R33/34061Helmholtz coils G01R33/34069Saddle coils G01R33/34076Birdcage coils G01R33/34084implantable coils or coils being geometrically adaptable to the sample G01R33/34092RF coils specially adapted for NMR spectrometers G01R33/341comprising surface coils G01R33/3415comprising arrays of sub-coils G01R33/343of slotted-tube or loop-gap type G01R33/345of waveguide type G01R33/3453Transverse electromagnetic [TEM] coils G01R33/3456Stripline resonators G01R33/36Electrical details G01R33/3607RF waveform generators G01R33/3614RF power amplifiers G01R33/3621NMR receivers or demodulators G01R33/3628Tuning/matching of the transmit/receive coil G01R33/3635Multi-frequency operation G01R33/3642Mutual coupling or decoupling of multiple coils G01R33/365Decoupling of multiple RF coils wherein the multiple RF coils have the same function in MR G01R33/3657Decoupling of multiple RF coils wherein the multiple RF coils do not have the same function in MR G01R33/3664Switching for purposes other than coil coupling or decoupling G01R33/3671involving modulation of the quality factor of the RF coil G01R33/3678involving quadrature drive or detection G01R33/3685Means for reducing sheath currents G01R33/3692involving signal transmission without using electrically conductive connections G01R33/38Systems for generation, homogenisation or stabilisation of the main or gradient magnetic field G01R33/3802Manufacture or installation of magnet assemblies; Additional hardware for transportation or installation of the magnet assembly or for providing mechanical support to components of the magnet assembly G01R33/3804Additional hardware for cooling or heating of the magnet assembly, for housing a cooled or heated part of the magnet assembly or for temperature control of the magnet assembly G01R33/3806Open magnet assemblies for improved access to the sample G01R33/3808Magnet assemblies for single-sided MR wherein the magnet assembly is located on one side of a subject only; Magnet assemblies for inside-out MR G01R33/381using electromagnets G01R33/3815with superconducting coils G01R33/383using permanent magnets G01R33/385using gradient magnetic field coils G01R33/3852Gradient amplifiers; means for controlling the application of a gradient magnetic field to the sample G01R33/3854means for active and/or passive vibration damping or acoustical noise suppression in gradient magnet coil systems G01R33/3856Means for cooling the gradient coils or thermal shielding of the gradient coils G01R33/3858Manufacture and installation of gradient coils, means for providing mechanical support to parts of the gradient-coil assembly G01R33/387Compensation of inhomogeneities G01R33/3873using ferromagnetic bodies; Passive shimming G01R33/3875using correction coil assemblies G01R33/389Field stabilisation G01R33/42Screening G01R33/421of main or gradient magnetic field G01R33/4215of the gradient magnetic field G01R33/422of the radio frequency field G01R33/44using nuclear magnetic resonance [NMR] G01R33/441Nuclear Quadrupole Resonance [NQR] Spectroscopy and Imaging G01R33/443Assessment of an electric or a magnetic field G01R33/445MR involving a non-standard magnetic field B0 G01R33/446Multifrequency selective RF pulses G01R33/448Relaxometry G01R33/46NMR spectroscopy G01R33/4608RF excitation sequences for enhanced detection G01R33/4616using specific RF pulses or specific modulation schemes G01R33/4625Processing of acquired signals G01R33/4633Sequences for multi-dimensional NMR G01R33/4641Sequences for NMR spectroscopy of samples with ultrashort relaxation times such as solid samples G01R33/465applied to biological material G01R33/48NMR imaging systems G01R33/4802Travelling-wave MR G01R33/4804Spatially selective measurement of temperature or pH G01R33/4806Functional imaging of brain activation G01R33/4808Multimodal MR G01R33/481MR combined with positron emission tomography [PET] or single photon emission computed tomography [SPECT] G01R33/4812MR combined with X-ray or computed tomography [CT] G01R33/4814MR combined with ultrasound G01R33/4816NMR imaging of samples with ultrashort relaxation times such as solid samples G01R33/4818MR characterised by data acquisition along a specific k-space trajectory or by the temporal order of k-space coverage G01R33/482using a Cartesian trajectory G01R33/4822in three dimensions G01R33/4824using a non-Cartesian trajectory G01R33/4826in three dimensions G01R33/4828Resolving the MR signals of different chemical species G01R33/483with selection of signals or spectra from particular regions of the volume G01R33/4831using B1 gradients G01R33/4833using spatially selective excitation of the volume of interest G01R33/4835of multiple slices G01R33/4836using an RF pulse being spatially selective in more than one spatial dimension G01R33/4838using spatially selective suppression or saturation of MR signals G01R33/485based on chemical shift information CSI or spectroscopic imaging G01R33/50based on the determination of relaxation times G01R33/54Signal processing systems G01R33/543Control of the operation of the MR system G01R33/546Interface between the MR system and the user G01R33/56Image enhancement or correction G01R33/5601involving use of a contrast agent for contrast manipulation G01R33/5602by filtering or weighting based on different relaxation times within the sample G01R33/5604Microscopy; Zooming G01R33/5605by transferring coherence or polarization from a spin species to another G01R33/5607by reducing the NMR signal of a particular spin species G01R33/5608Data processing and visualization specially adapted for MR G01R33/561by reduction of the scanning time, i.e. fast acquiring systems G01R33/5611Parallel magnetic resonance imaging G01R33/5612Parallel RF transmission G01R33/5613Generating steady state signals G01R33/5614using a fully balanced steady-state free precession [bSSFP] pulse sequence G01R33/5615Echo train techniques involving acquiring plural, differently encoded, echo signals after one RF excitation G01R33/5616using gradient refocusing G01R33/5617using RF refocusing G01R33/5618using both RF and gradient refocusing G01R33/5619by temporal sharing of data G01R33/563of moving material G01R33/56308Characterization of motion or flow; Dynamic imaging G01R33/56316involving phase contrast techniques G01R33/56325Cine imaging G01R33/56333Involving spatial modulation of the magnetization within an imaged region G01R33/56341Diffusion imaging G01R33/5635Angiography G01R33/56358Elastography G01R33/56366Perfusion imaging G01R33/56375Intentional motion of the sample during MR G01R33/56383involving motion of the sample as a whole G01R33/56391involving motion of a part of the sample with respect to another part of the sample G01R33/565Correction of image distortions G01R33/56509due to motion, displacement or flow G01R33/56518due to eddy currents G01R33/56527due to chemical shift effects G01R33/56536due to magnetic susceptibility variations G01R33/56545caused by finite or discrete sampling G01R33/56554caused by acquiring plural, differently encoded echo signals after one RF excitation G01R33/56563caused by a distortion of the main magnetic field B0 G01R33/56572caused by a distortion of a gradient magnetic field G01R33/56581due to Maxwell fields G01R33/5659caused by a distortion of the RF magnetic field G01R33/567gated by physiological signals i.e. synchronization of acquired MR data with periodical motion of an object of interest G01R33/5673Gating or triggering based on a physiological signal other than an MR signal G01R33/5676Gating or triggering based on an MR signal G01R33/58Calibration of imaging systems G01R33/583Calibration of signal excitation or detection systems G01R33/586for optimal flip angle of RF pulses G01R33/60using electron paramagnetic resonance G01R33/62using double resonance G01R33/64using cyclotron resonance