Hi LLC

Ricardo Jiménez-Martínez

Jamu Alford

Micah Ledbetter

Ethan Pratt

Benjamin Shapiro

Julian Kates-Harbeck

Geoffrey Iwata

Hooman Mohseni

Husam Katnani

Michael Henninger

Bryan Johnson

Benjamin Siepser

Michael Romalis

Argyrios Dellis

Kayla Wright-Freeman

Zachary Bednarke

Vincent Maurice

Anthony Zorzos

A magnetic field measurement system includes a light source that emits a light beam; an optical fiber to transmit the light beam; a variable optical attenuator to increase stability of an intensity of the light beam; a beam splitter to divide the light beam into an OPM light beam and a monitor light beam; a monitor detector to detect the monitor light beam and generate a monitor signal; a vapor cell with alkali metal atoms disposed therein and configured for transmission of the OPM light beam through the vapor cell; an OPM detector to detect the OPM light beam after transmission through the vapor cell and generate an OPM signal; and a group delay filter to combine the monitor signal and the OPM signal to generate a reduced noise OPM signal, where the group delay filter accounts for a phase difference between the monitor signal and the OPM signal.

Devices, systems, and methods for suppressing optical noise in optically pumped magnetometers

An actuated magnetic field is generated at a plurality of distinct frequencies that at least partially cancels an outside magnetic field at the plurality of distinct frequencies, thereby yielding a total residual magnetic field. The total residual magnetic field is coarsely detected and a plurality of coarse error signals are respectively output. The total residual magnetic field is finely detected and a plurality of fine error signals are respectively output. The actuated magnetic field is controlled respectively at the plurality of distinct frequencies at least partially based on at least one of the plurality of coarse error signals, and finely controlled respectively at the plurality of distinct frequencies at least partially based on at least one of the plurality of fine error signals.

Nested and parallel feedback control loops for ultra-fine measurements of magnetic fields from the brain using a neural detection system

A mental state awareness system comprises a non-invasive brain interface assembly configured for detecting brain activity of a user, a processor configured for determining a mental state of a user based on the detected brain activity, and a biofeedback device configured for automatically providing biofeedback to the user indicative of the determined mental state of the user.

Biofeedback for awareness and modulation of mental state using a non-invasive brain interface system and method

A calibration system for a magnetometer having an unknown gain is disclosed. A calibration magnetic field is generated at a calibration frequency of a known amplitude at the magnetometer. A measurement of the calibrating magnetic field is reported by the magnetometer. A ratio of an amplitude of the calibration magnetic field measurement reported by the magnetometer and the known amplitude of the calibrating magnetic field at the magnetometer is computed. The unknown gain of the magnetometer is determined at least partially based on computed ratio.

Self-calibration of flux gate offset and gain drift to improve measurement accuracy of magnetic fields from the brain using a wearable neural detection system

At least one magnetic field actuator is configured for generating an actuated magnetic field that at least partially cancels an outside magnetic field, thereby yielding a total residual magnetic field. A plurality of magnetometers are configured for taking measurements of the total residual magnetic field. The magnetometers include a plurality of coarse magnetometers and a plurality of fine magnetometers. A processor is configured for acquiring the total residual magnetic field measurements from the coarse magnetometers, estimating the total residual magnetic field at the fine magnetometers based on total residual magnetic field measurements acquired from the plurality of coarse magnetometers, and controlling the actuated magnetic field at least partially based on the total residual magnetic field estimates at the fine magnetometers in a manner that suppresses the total residual magnetic field at the fine magnetometers to a baseline level, such that at least one of the fine magnetometers is in-range.

Estimating the magnetic field at distances from direct measurements to enable fine sensors to measure the magnetic field from the brain using a neural detection system

A magnetocardiography (MCG) system includes a passively shielded enclosure having walls defining the passively shielded enclosure, each of the walls including passive magnetic shielding material to reduce an ambient background magnetic field within the passively shielded enclosure; an MCG measurement device including optically pumped magnetometers (OPMs); and active shield coils within the passively shielded enclosure and stationary relative to the passively shielded enclosure and the MCG measurement device, wherein the active shield coils are configured to further reduce the ambient background magnetic field within a user area of the passively shielded enclosure.

Systems and methods for recording biomagnetic fields of the human heart

A shielding arrangement for a magnetoencephalography (MEG) system includes a passively shielded enclosure having a plurality of walls defining the passively shielded enclosure, each of the plurality of walls including passive magnetic shielding material to reduce an ambient background magnetic field within the passively shielded enclosure; a vestibular wall extending from a first vertical wall to define, and at least partially separate, a vestibular area of the passively shielded enclosure adjacent the doorway and a user area of the passively shielded enclosure; and active shield coils distributed within the passively shielded enclosure and configured to further reduce the ambient background magnetic field within the user area of the passively shielded enclosure.

Systems and methods for recording neural activity

A magnetic field recording system includes a headgear to be placed on a user; optically pumped magnetometers (OPMs) disposed in or on the headgear to detect magnetic fields; at least two sensing modalities selected from the following: i) a magnetic sensing modality, ii) an optical sensing modality, or iii) an inertial sensing modality; and a tracking unit configured to receive, from each of the at least two sensing modalities, a corresponding magnetic data stream, optical data stream, or inertial data stream and to track a position or orientation of the headgear or user; and a system controller configured to control operation of the OPMs and to receive, from the tracking unit, the position or orientation of the headgear or user.

Systems and methods for multimodal pose and motion tracking for magnetic field measurement or recording systems

A magnetic field measurement system includes a magnetometer having at least one vapor cell, at least one light source to direct at least two light beams through the vapor cell(s), and at least one detector; at least one magnetic field generator to modify an external magnetic field experienced by the vapor cell(s); and at least one processor configured for: applying a first modulation pattern, b(t), to the magnetic field generator(s) to modulate a magnetic field at the vapor cell(s), where b(t)=[ccos(&#x3c9;t)+ssin(&#x3c9;t), ccos(&#x3c9;t)+ssin(&#x3c9;t), ccos(&#x3c9;t)+ssin(&#x3c9;t)], where c, s, c, s, c, and sare amplitudes and &#x3c9; is a frequency; directing the light source(s) to direct the light beams through the vapor cell(s); receiving signals from the detector(s); and determining three orthogonal components of the external magnetic field using the received signals. Multi-frequency modulation patterns can alternatively be used.

Devices, systems, and methods with optical pumping magnetometers for three-axis magnetic field sensing

An active shield magnetometry system comprises at least one magnetic field actuator configured for generating an actuated magnetic field that at least partially cancels an outside magnetic field, thereby yielding a total residual magnetic field. The active shield magnetometry system further comprises a plurality of magnetometers respectively configured for measuring the total residual magnetic field and outputting a plurality of total residual magnetic field measurements. The active shield magnetometry system further comprises at least one feedback control loop comprising at least one optimal linear controller configured for controlling the actuated magnetic field at least partially based on at least one of the plurality of total residual magnetic field measurements respectively output by at least one of the plurality of magnetometers.

Optimal methods to feedback control and estimate magnetic fields to enable a neural detection system to measure magnetic fields from the brain

A magnetic field measurement system includes at least one magnetometer having a vapor cell, a light source to direct light through the vapor cell, and a detector to receive light directed through the vapor cell; at least one magnetic field generator disposed adjacent the vapor cell; and a feedback circuit coupled to the at least one magnetic field generator and the detector of the at least one magnetometer. The feedback circuit includes a first feedback loop that includes a first low pass filter with a first cutoff frequency and a second feedback loop that includes a second low pass filter with a second cutoff frequency. The first and second feedback loops are configured to compensate for magnetic field variations having a frequency lower than the first or second cutoff frequency, respectively.

Magnetic field measurement systems and methods employing feedback loops with a loops with a low pass filter

A magnetic field recording system includes a headgear for a user; optically pumped magnetometers (OPMs) disposed in or on the headgear to detect magnetic fields and, in response to the detection, produce magnetic field data; at least one sensing modality including an optical sensing modality having at least one light source and at least one camera or light detector to receive light reflected or directed from the user and to produce an optical data stream; a tracking unit to receive the optical data stream and track a position or orientation of the headgear or user; a system controller to control operation of the OPMs and receive, from the tracking unit, the position or orientation of the headgear or user; and a processor to receive the optical data stream and the magnetic field data from the OPMs and analyze the magnetic field data using the optical data stream for validation.

Magnetic field measurement or recording systems with validation using optical tracking data

An optically pumped magnetometer includes a vapor cell; at least one light source configured to produce a pump light beam and a probe light beam; a lens disposed between the at least one light source and the vapor cell; a quarter wave plate disposed between the lens and the vapor cell; a mirror configured to receive the pump light beam and probe light beam after passing through the vapor cell and reflect the pump light beam and probe light beam back through the vapor cell, the quarter wave plate, and the lens; and at least one detector configured to receive the probe light beam reflected by the mirror.

Compact optically pumped magnetometers with pump and probe configuration and systems and methods

A magnetometer can include a single, integrated, unitary structure that has a gas cell defining a cavity having a vapor or vaporizable material disposed therein, a collimating element coupled to the gas cell and configured for collimating light directed toward the gas cell, and a lens element coupled the gas cell and configured for redirecting at least a portion of light that has passed through the gas cell. Additionally or alternatively, a gas cell of a magnetometer may be made of sapphire.

Integrated gas cell and optical components for atomic magnetometry and methods for making and using

A magnetic field measurement system includes at least one magnetometer; and at least one flux concentrator made of a high magnetic permeability material and configured to receive magnetic field signals from a source, to concentrate the magnetic field signals or reorient the magnetic field signals in a preselected direction, and to direct the concentrated or reoriented magnetic field signals toward at least one of the at least one magnetometer. In addition to, or as an alternative to, the flux concentrator, the system can include a passive shield made of the high magnetic permeability material. The system may also include active shielding.

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Culver City, CA, United States of America

Ricardo Jiménez-Martínez