An Optically Pumped Magnetometer (OPM) system is configured to characterize a magnetic field. The OPM system comprises an OPM sensor that is coupled to an OPM cable that is coupled to an OPM connector that is detachably coupled to an OPM controller. The OPM connector stores OPM operational data. The OPM controller reads the OPM operational data when the OPM connector is coupled to an OPM controller. The OPM controller generates sensor control signals based on the OPM operational data and transfers the control signals to the OPM sensor. The OPM sensors characterize the magnetic field in response to the sensor control signals and transfer output signals that characterize the magnetic field to the OPM controller. The OPM controller models the magnetic field based on the output signals and transfers new OPM operational data to OPM connector. The OPM connector stores the new OPM operational data in the memory.

Various embodiments of the present technology relate generally to the field of imaging the spatial distribution of magnetic field of biologic and non-biologic materials that may change over time and more particularly to the apparatus and methods for making such a static or dynamic spatial imaging of magnetic field distributions. Some embodiments provide for apparatus and methods for a novel magnetographic camera which enables a unique ability to determine the spatial distribution of magnetic field in a biological or non-biological sample with high spatial and temporal resolutions and high sensitivity. The use of these embodiments will greatly expand the applications of OPM-based cameras in medicine, science and industry.

Ferrimagnetic oscillator magnetometers do not use lasers to stimulate fluorescence emission from defect centers in solid-state hosts (e.g., nitrogen vacancies in diamonds). Instead, in a ferrimagnetic oscillator magnetometer, the applied magnetic field shifts the resonance of entangled electronic spins in a ferrimagnetic crystal. These spins are entangled and can have an ensemble resonance linewidth of approximately 370 kHz to 10 MHz. The resonance shift produces microwave sidebands with amplitudes proportional to the magnetic field strength at frequencies proportional to the magnetic field oscillation frequency. These sidebands can be coherently averaged, digitized, and coherently processed, yielding magnetic field measurements with sensitivities possibly approaching the spin projection limit of 1 attotesla/√{square root over (Hz)}. The encoding of magnetic signals in frequency rather than amplitude relaxes or removes otherwise stringent requires on the digitizer.

Various methods and systems are provided for correcting transmit attenuation of an amplifier of a transmit radio frequency (RF) coil for use in a magnetic resonance imaging (MRI) system. In one example, a method includes setting a reference value of transmit attenuation for an amplifier of a transmit radio frequency (RF) coil, acquiring a two-dimensional B.sub.1 field map with the transmit attenuation set at the reference value, determining a mean flip angle from the B.sub.1 field map, determining a transmit attenuation correction value based on a prescribed flip angle and the mean flip angle, correcting the reference value of transmit attenuation with the transmit attenuation correction value to obtain a final value of transmit attenuation, and performing an MRI scan with the transmit attenuation set at the value.

Magnetic resonance (MR) data are acquired from a volume segment of an examination object and an MR image composed of multiple image pixels is reconstructed therefrom. For a magnetic field assumed to have been generated by the scanner, a summed field deviation is calculated, from which a respective displacement vector is calculated for each image pixel. A signal portion is assigned to each image pixel that has been displaced with the respective displacement vector from the respective image pixel. The summed field deviation is the sum of deviations caused by at least two of: non-linearities in gradient coils, Maxwell fields, field inhomogeneities independent of the gradients, and dynamic field disturbances.

Some aspects comprise a tuning system configured to tune a radio frequency coil for use with a magnetic resonance imaging system comprising a tuning circuit including at least one tuning element configured to affect a frequency at which the radio frequency coil resonates, and a controller configured to set at least one value for the tuning element to cause the radio frequency coil to resonate at approximately a Larmor frequency of the magnetic resonance imaging system determined by the tuning system. Some aspects include a method of automatically tuning a radio frequency coil comprising determining information indicative of a Larmor frequency of the magnetic resonance imaging system, using a controller to automatically set at least one value of a tuning circuit to cause the radio frequency coil to resonate at approximately the Larmor frequency based on the determined information.

Quantitative susceptibility mapping methods, systems and computer-accessible medium generate images of tissue magnetism property from complex magnetic resonance imaging data using the Bayesian inference approach, which minimizes a cost function comprising of a data fidelity term and regularization terms. The data fidelity term is constructed directly from the multiecho complex magnetic resonance imaging data. The regularization terms include a prior constructed from matching structures or information content in known morphology, and a prior constructed from regions of low susceptibility contrasts characterized on image features. The quantitative susceptibility map can be determined by minimizing the cost function that involves nonlinear functions in modeling the obtained signals, and the corresponding inverse problem is solved using nonconvex optimization using a scaling approach or deep neural network. The nonconvex optimization is also developed for solving other inverse problems of nonlinear signal models in fat-water separation, tissue transport and oxygen extraction fraction.

A measurement device for measuring MR signals in a MR device may include first and second magnetometers and a controller. The first magnetometer may be a quantum spin magnetometer that includes a sensor material having a spin defect center including Zeeman splitting states dependent on an external magnetic field of the MR device, an optical excitation source and a microwave excitation source for electromagnetically exciting the sensor material, and a measurement sensor for measuring optical signals emitted by the excited sensor material element and depending on the Zeeman splitting states. The controller may be configured to determine a working frequency of the microwave excitation source of the first magnetometer from the total magnetic field strength measured by the second magnetometer, and control the microwave excitation source to use the determined working frequency as microwave frequency, such that the first magnetometer measures the MR signals as the optical signal.

A measurement device for measuring MR signals in a MR device may include first and second magnetometers and a controller. The first magnetometer may be a quantum spin magnetometer that includes a sensor material having a spin defect center including Zeeman splitting states dependent on an external magnetic field of the MR device, an optical excitation source and a microwave excitation source for electromagnetically exciting the sensor material, and a measurement sensor for measuring optical signals emitted by the excited sensor material element and depending on the Zeeman splitting states. The controller may be configured to determine a working frequency of the microwave excitation source of the first magnetometer from the total magnetic field strength measured by the second magnetometer, and control the microwave excitation source to use the determined working frequency as microwave frequency, such that the first magnetometer measures the MR signals as the optical signal.

A system and method of mapping and correcting the inhomogeneity of a magnetic field within an object using an Magnetic Resonance Imaging (MRI) system where there is a single dominant resonance. The method includes acquiring at least three MRI images, each at different echo times (TE). At least two ΔTE images (ΔTE.sub.i=1 . . . N) are generated based on the at least three MRI images, wherein the subscripts I=1 N refer to images with sequentially increasing ΔTE times. Aliasing in the ΔTE.sub.1 image is permitted. The ΔTE times of ΔTE.sub.1 and ΔTE.sub.2 are set such that the alias points at which wrapping occurs in ΔTE.sub.1 does not overlap with the alias points of ΔTE.sub.2. Each ΔTE image is unwrapped. A final B0 map is set to the unwrapped ΔTE.sub.N image.