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.

A magnetic sensor includes a piezomagnetic component which includes a first piezomagnetic element and a second piezomagnetic element that are arranged opposite to each other, a magnetostrictive component which includes a first magnetostrictive element and a second magnetostrictive element arranged opposite to each other on the same side of the first piezomagnetic element and the second piezomagnetic element, respectively, and a piezoelectric component which includes a first piezoelectric element deposited underneath the first piezomagnetic element, a second piezoelectric element deposited underneath the second piezomagnetic element, a third piezoelectric element deposited underneath the first magnetostrictive element, and a fourth piezoelectric element deposited underneath the second magnetostrictive element. The first piezoelectric element and the second piezoelectric element are electrically connected to a power supply circuit, and produce first deformation, which is applied to the first piezomagnetic element and the second piezomagnetic element to produce an alternating magnetic field.

A magnetoresistive Z-axis gradient sensor chip, which is used to detect the gradient in the XY plane of a Z-axis magnetic field component generated by a magnetic medium; the sensor chip comprises a Si substrate, a collection of two or two groups of flux guide devices separated a distance Lg and an arrangement of electrically interconnected magnetoresistive sensor units. The magnetoresistive sensor units are located on the Si substrate and located above or below the edge of the flux guide devices as well; the flux guide devices convert the component of the Z-axis magnetic field into the direction parallel to the surface of the Si substrate along the sensing axis direction of the magnetoresistive sensing units. The magnetoresistive sensor units are electrically interconnected into a half bridge or a full bridge gradiometer arrangement, wherein the opposite bridge arms are separated by distance Lg. This sensor chip can be utilized with a PCB or in combination with a PCB plus back-bias magnet with casing. The sensor measures the Z-axis magnetic field gradient by using magnetoresistive sensors with in-plane sensing axes. This sensor chip has several advantages relative to a Hall Effect sensor device, including smaller size, lower power consumption, and higher magnetic field sensitivity.

A method of determining an orientation α,β of a magnet which is pivotable about a reference position having a predefined position relative to a semiconductor substrate, comprising: a) determining at least two of the following magnetic field gradients: i) a first magnetic field gradient dBx/dx; ii) a second magnetic field gradient dBy/dy; iii) a third magnetic field gradient dBz/dx; iv) a fourth magnetic field gradient dBz/dy; b) determining a first angle α based on at least one of the magnetic field gradients; c) determining a second angle β based on at least one of the magnetic field gradients. A sensor device is configured for performing this method. A sensor system includes such sensor device and a magnet, optionally connected to a joystick.

A method of magnetic sensing uses at least two magnetic sensing elements including a first and a second magnetic sensor element. The method includes: a) measuring in a first configuration a combination of the first and second signal obtained from both sensors; b) measuring in a second configuration an individual signal obtained from the first sensor only; c) testing a consistency of the combined signal and the individual signal, or testing a consistency of signals derived therefrom, in order to detect an error. A sensor device is configured for performing this method. A sensor system includes the sensor device and optionally a second processor connected thereto.

An information processing device and a magnetic sensor system are provided, in which accuracy of frequency measurement is less likely to deteriorate even though the frequency of output signals outputted from the magnetic sensor increases, and which have detection limits for high frequency measurement even with a minute frequency change rate. An information processing device 120 includes: an obtaining part 31 obtaining an output signal outputted by a magnetic sensor and oscillating at a frequency determined in response to strength of a magnetic field; a frequency determination part 32 utilizing interference between the output signal and a reference signal with a reference frequency, which is a frequency used as a reference, to determine the frequency of the output signal; and a magnetic field calculation part 40 calculating the strength of the magnetic field based on the determined frequency of the output signal.

A sensor device includes a current conductor designed to carry a measurement current, and a magnetic field sensor chip having a sensor element, wherein the magnetic field sensor chip is designed to detect a magnetic field at the location of the sensor element. The sensor device furthermore includes an encapsulation material, wherein the magnetic field sensor chip is encapsulated by the encapsulation material, and a soft magnet secured to the encapsulation material and designed to concentrate the magnetic field at the location of the sensor element. The magnetic field sensor chip and the soft magnet are galvanically isolated from one another by the encapsulation material.

A magnetic sensor 1 includes: a nonmagnetic substrate 10; a sensitive element 31 laminated on the substrate 10, the sensitive element 31 being made of a soft magnetic material, the sensitive element 31 having a longitudinal direction and a transverse direction and having uniaxial magnetic anisotropy in a direction intersecting the longitudinal direction, the sensitive element 31 being configured to sense a magnetic field by a magnetic impedance effect; and a pair of thin-film magnets 20a, 20b laminated on the substrate 10 and disposed to face each other in the longitudinal direction across the sensitive element 31, the pair of thin-film magnets 20a, 20b being configured to apply a magnetic field in the longitudinal direction of the sensitive element 31.

A magnetic sensor includes: a non-magnetic substrate; and a sensitive element 31 having a longitudinal direction and a short direction, provided with uniaxial magnetic anisotropy in a direction crossing the longitudinal direction, and sensing a magnetic field by a magnetic impedance effect, wherein the sensitive element 31 includes plural soft magnetic material layers 105a to 105d and plural non-magnetic material layers 106a to 106c configured with a non-magnetic material and laminated between the plural soft magnetic material layers 105a to 105d, and the soft magnetic material layers 105a to 105d facing each other with each of the non-magnetic material layers 106a to 106c interposed therebetween are antiferromagnetically coupled.

A method can use a current sensor that can include a magnetic flux concentrator along with first and second magnetic field sensing elements disposed proximate to the magnetic flux concentrator, wherein the magnetic flux concentrator is operable to influence a direction of first and second magnetic fields at the first and second magnetic field sensing elements, respectively, the first and second magnetic fields resulting from an electrical current passing through a conductor, the first and second magnetic field sensing elements operable to generate first and second signals, respectively, in response to the first and second magnetic fields, respectively, wherein the current sensor can also include a differencing circuit operable to subtract the first and second signals to generate a difference signal related to the electrical current.