Abstract: An optical measurement system includes a first light source configured to emit a first light pulse toward a target, a second light source configured to emit a second light pulse toward the target, a first detector, a second detector, and a processing unit. The processing unit is configured to determine a plurality of temporal distributions of photons included in the first light pulse and the second light pulse and detected by the first detector and the second detector after the photons are scattered by the target. The processing unit is further configured to determine, based on the plurality of temporal distributions, a distance between the first light source and the second detector.

Abstract: An illustrative method includes accessing, by a computing device, a model simulating light scattered by a simulated target, the model comprising a plurality of parameters. The method further includes generating, by the computing device, a set of possible histogram data using the model with a plurality of values for the parameters. The method further includes determining, by the computing device, a set of components that represent the set of possible histogram data, the set of components having a reduced dimensionality from the set of possible histogram data.

Abstract: 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.

Abstract: An illustrative optical measurement system includes a light source configured to emit light directed at a target, an array of photodetectors configured to detect photons of the light after the light is scattered by the target, and a processing unit. The processing unit is configured to measure a noise level of a photodetector included in the array of photodetectors and determine that the noise level meets a predetermined threshold. The processing unit is further configured to prevent, based on the determining that the noise level meets the predetermined threshold, an output of the photodetector from being used in generating a histogram based on a temporal distribution of photons detected by the array of photodetectors.

Abstract: An illustrative multimodal measurement system includes a wearable assembly configured to be worn by a user and comprising a plurality of light sources each configured to emit light directed at a target within the user, a plurality of detectors configured to detect arrival times for photons of the light after the light is scattered by the target, and a plurality of electrodes configured to be external to the user and detect electrical activity of the target.

Abstract: An exemplary system includes a processor, a wearable device comprising a plurality of slots, and a first module including a plurality of detectors and a module control circuit. The processor is configured to successively transmit, to each slot of the plurality of slots, a command to enable a respective module located in each slot. The processor is further configured to determine, based on an acknowledgment received from the module control circuit, that the first module is enabled and located in a first slot, and to successively transmit, based on the determining that the first module is enabled and located in the first slot, a plurality of detector address identifiers. The module control circuit is configured to successively place the plurality of detectors into an enumeration mode in which each detector of the plurality of detectors is assigned a different detector address identifier of the plurality of detector address identifiers.

Abstract: 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.

Abstract: An exemplary system includes a light source and a control circuit configured to apply voltage having a first polarity to the light source for a first time period to provide a threshold charge for the light source to start an emission of a light pulse that is directed at a target within a body. The control circuit is further configured to apply voltage having a second polarity opposite the first polarity to the light source for a second time period subsequent to the first time period to discharge the light source to stop the emission of the light pulse.

Abstract: An optical measurement system includes a wearable device configured to be worn on a body of a user and a position alignment system. The wearable device includes a support assembly and a wearable assembly supported by the support assembly. The wearable assembly includes a plurality of light sources configured to emit a plurality of light pulses toward a target within the body of the user and a plurality of detectors each configured to receive a set of photons included in a light pulse included in the plurality of light pulses after the set of photons is scattered by the target. The position alignment system is configured to facilitate positioning of the wearable assembly at a same position on the body of the user during different use sessions of the wearable device.

Abstract: In a non-invasive optical detection system and method, sample light is delivered into a scattering medium. A first portion of the sample light passing through a volume of interest exits the scattering medium as signal light, and a second portion of the sample light passing through a volume of non-interest exits the scattering medium as background light that is combined with the signal light to create a sample light pattern. Reference light is combined with the sample light pattern to create an interference light pattern having a holographic beat component. Ultrasound is emitted into the volume of non-interest in a manner that decorrelates the background light of the sample light pattern from the holographic beat component. The holographic beat component is detected during the measurement period. An optical parameter of the volume of interest is determined based on the detected holographic beat component.

Abstract: An exemplary optical measurement system includes a signal generator configured to generate a signal and a processing unit configured to direct the signal generator to apply the signal to a component within the optical measurement system, generate, based on a response of the component to the signal, characterization data representative of a timing uncertainty associated with the component, and perform, based on the characterization data, an action associated with the component.

Abstract: A neural phantom device configured and arranged to produce a magnetic field to simulate a neural signal. The neural phantom device includes a driver having a signal source configured to produce a simulated neural signal, and either i) a carrier wave source configured to produce a carrier wave having a frequency of at least 250 Hz or ii) an optical carrier wave source configured to produce an optical carrier wave, wherein the driver is configured to modulate the simulated neural signal using the carrier wave or optical carrier wave to generate a modulated signal. The neural phantom device also includes a phantom configured to receive the modulated signal, demodulate the modulated signal to recover the simulated neural signal, and generate the magnetic field in response to the simulated neural signal.

Abstract: An exemplary optical measurement system includes a light source configured to emit light directed at a target. The optical measurement system further includes a photodetector configured to detect a photon of the light after the light is scattered by the target. The optical measurement system further includes a control circuit configured to receive a first input voltage that is a temperature-dependent voltage. The control circuit is further configured to receive a second input voltage that is a temperature-invariant voltage. The control circuit is further configured to output, based on a combination of the first input voltage and the second input voltage, a bias voltage for the photodetector, wherein the combination of the first and second input voltages is configured to cause the bias voltage to vary based on temperature.

Abstract: An exemplary photodetector system includes a plurality of photodetectors connected in parallel and a processor communicatively coupled to the plurality of photodetectors. The processor is configured to receive an accumulated output from the plurality of photodetectors. The accumulated output represents an accumulation of respective outputs from each of the plurality of photodetectors detecting photons during a predetermined measurement time period that occurs in response to a light pulse being directed toward a target within a body. The processor is further configured to determine, based on the accumulated output, a temporal distribution of photons detected by the plurality of photodetectors, and generate, based on the temporal distribution of photons, a histogram representing a light pulse response of the target within the body.

Abstract: A wearable module assembly for an optical measurement system includes a first wearable module, a second wearable module, and a connector. The first and second wearable modules each include a light source configured to emit a light pulse toward a target within a body of a user, a housing that houses the light source and the plurality of detectors and includes a substantially hexagonal surface that faces a surface of the body of the user when the wearable module assembly is worn by the user, and a plurality of detectors each positioned at a fixed distance from the first light source and each configured to detect a set of photons included in the light pulse after the set of photons are scattered by the target. The connector directly connects the first wearable module and the second wearable module at mutually-facing side surfaces of the respective housings.

Abstract: A light intensity modulator includes an input optical fiber; an output optical fiber; an optical arrangement having a lens, where the optical arrangement is configured to receive light from the input optical fiber, pass the light through the lens, and direct the light to the output optical fiber; and a piezoelectric device coupled to the lens, where the piezoelectric device is configured for moving the lens to alter overlap of the output optical fiber and the light directed to the output optical fiber to modulate intensity of light in the output optical fiber.

Abstract: 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.

Abstract: Source light having a range of optical wavelengths is generated. The source light is split into sample light and reference light. The sample light is delivered into a sample, such that it is scattered by the sample, resulting in signal light that exits the sample. The signal light and reference light are combined into an interference light pattern having optical modes. Different subsets of the optical modes of the interference light pattern are respectively detected, and high-bandwidth analog signals respectively corresponding to the different subsets of optical modes of the interference light pattern are output. At least one characteristic is extracted from each of the plurality of high-bandwidth analog signals, and low-bandwidth digital signals respectively comprising the extracted characteristics are output. The sample is analyzed based on the low-bandwidth digital signals.

Abstract: An illustrative system includes an extended reality system and a brain interface system configured to be concurrently worn by a user. The extended reality system is configured to provide the user with an extended reality experience and output a timing signal while the extended reality experience is being provided to the user, the timing signal representing a plurality of timing events that occur during the extended reality experience. The brain interface system is configured to receive the timing signal from the extended reality system while the extended reality experience is being provided to the user, acquire brain activity measurements while the extended reality experience is being provided to the user, and output measurement timestamp data representative of a temporal association of the brain activity measurements with the timing events.

Abstract: 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.