Abstract: A wearable module for use in an optical measurement system includes a housing including a top surface, a light guide including a distal end portion adapted to protrude from the top surface of the housing, and a spring member configured to bias the distal end portion of the light guide away from the top surface of the housing. The light guide is configured to receive, at the distal end portion, photons from a light pulse scattered by a target within a body of a user and guide the received photons toward a photodetector.

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: 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: An optical measurement system includes a wearable module having at least one time-resolved single photon photodetector configured to detect photons from at least one light pulse after the at least one light pulse is scattered by a target within a body of a user; at least one light guide configured to receive the photons and guide the photons to the at least one photodetector; and a housing that houses both the at least one photodetector and at least a portion of the at least one light guide. The optical measurement system further includes a signal processing circuit configured to determine a temporal distribution of the photons detected by the at least one photodetector and generate a histogram based on the temporal distribution of the photons.

Abstract: An exemplary controller may include a single clock source configured to generate a single clock signal used to drive one or more components within a plurality of magnetometers and a plurality of differential signal measurement circuits configured to measure current output by a photodetector of each of the plurality of magnetometers.

Abstract: An exemplary wearable sensor unit includes 1) a magnetometer comprising a vapor cell comprising an input window and containing an alkali metal, and a light source configured to output light that passes through the input window and into the vapor cell along a transit path, and 2) a temperature control circuit external to the vapor cell and configured to create a temperature gradient within the vapor cell, the temperature gradient configured to concentrate the alkali metal within the vapor cell away from the transit path of the light.

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: An optical measurement system includes a wearable device including a support assembly configured to be worn on a body of a user 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. A position of the wearable assembly on the support assembly is adjustable.

Abstract: An exemplary magnetic field measurement system includes a wearable sensor unit that includes a magnetometer and a twisted pair cable interface assembly electrically connected to the magnetometer.

Abstract: A magnetic field measurement system includes a wearable device having a plurality of wearable sensor units. Each wearable sensor unit includes a plurality of magnetometers and a magnetic field generator configured to generate a compensation magnetic field configured to actively shield the plurality magnetometers from ambient background magnetic fields. A strength of a fringe magnetic field generated by the magnetic field generator of each of the wearable sensor units is less than a predetermined value at the plurality of magnetometers of each wearable sensor unit included in the plurality of wearable sensor units.

Abstract: A method of making an array of vapor cells for an array of magnetometers includes providing a plurality of separate vapor cell elements, each vapor cell element including at least one vapor cell; arranging the vapor cell elements in an alignment jig to produce a selected arrangement of the vapor cells; attaching at least one alignment-maintaining film onto the vapor cell elements in the alignment jig; transferring the vapor cells elements and the at least one alignment-maintaining film from the alignment jig to a mold; injecting a bonding material into the mold and between the vapor cell elements to bond the vapor cell elements in the selected arrangement; removing the at least one alignment maintaining film from the vapor cell elements; and removing the bonded vapor cells elements in the selected arrangement from the mold to provide the array of vapor.

Abstract: A magnetic field generator includes a first planar substrate, a second planar substrate positioned opposite to the first planar substrate and separated from the first planar substrate by a gap, a first wiring set on the first planar substrate, a second wiring set on the second planar substrate, and one or more interconnects between the first planar substrate and the second planar substrate. The one or more interconnects electrically connect the first wiring set with the second wiring set to form a continuous electrical path. The continuous electrical path forms a conductive winding configured to generate, when supplied with a drive current, a first component of a compensation magnetic field configured to actively shield a magnetic field sensing region located in the gap from ambient background magnetic fields along a first axis that is substantially parallel to the first planar substrate and the second planar substrate.

Abstract: An exemplary magnetic field measurement system includes a wearable sensor unit that includes a magnetometer and a twisted pair cable interface assembly electrically connected to the magnetometer.

Abstract: An exemplary magnetic field measurement system includes a wearable sensor unit and a single controller. The wearable sensor unit includes a plurality of magnetometers. The single controller is configured to generate a single clock signal and use the single clock signal to drive one or more components within the magnetometers.

Abstract: An exemplary controller may include a single clock source configured to generate a single clock signal used to drive one or more components within a plurality of magnetometers and a plurality of differential signal measurement circuits configured to measure current output by a photodetector of each of the plurality of magnetometers.

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: An exemplary magnetic field measurement system includes a wearable sensor unit that includes a magnetometer, a magnetic field generator configured to generate a compensation magnetic field configured to actively shield the magnetometer from ambient background magnetic fields, a twisted pair cable interface assembly electrically connected to the magnetometer, and a coaxial cable interface assembly electrically connected to the magnetic field generator.

Abstract: An exemplary magnetic field measurement system includes a wearable sensor unit and a controller. The wearable sensor unit includes 1) a magnetometer comprising a photodetector and 2) a magnetic field generator configured to generate a compensation magnetic field configured to actively shield the magnetometer from ambient background magnetic fields. The controller is configured to interface with the magnetometer and the magnetic field generator and includes a differential signal measurement circuit configured to measure current output by the photodetector.

Abstract: An exemplary magnetic field measurement system includes a wearable sensor unit and a single controller. The wearable sensor unit includes a plurality of magnetometers and a magnetic field generator configured to generate a compensation magnetic field configured to actively shield the magnetometers from ambient background magnetic fields. The single controller is configured to interface with the magnetometers and the magnetic field generator.

Abstract: A wearable module for use in an optical measurement system includes a housing including a top surface, a light guide including a distal end portion adapted to protrude from the top surface of the housing, and a spring member configured to bias the distal end portion of the light guide away from the top surface of the housing. The light guide is configured to receive, at the distal end portion, photons from a light pulse scattered by a target within a body of a user and guide the received photons toward a photodetector.