Magneto-resistance based nano-scale position sensor
AssigneeInternational Business Machines Corporation
InventorsCharalampos Pozidis, Deepak Ranjan Sahoo, Abu Sebastian
Life of this patent
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Abstract
A position sensor and method include a magnetic component, a first magneto-resistive sensor disposed in proximity to the magnet/coil; and a second magneto-resistive sensor disposed in proximity to the magnetic component and the first magneto-resistive sensor. The first magneto-resistive sensor and second magneto-resistive sensor are configured to sense changes in a stray magnetic field created by the magnetic component in accordance with a relative positional change between the magnetic component and the first and second magneto-resistive sensors.
Claims19
A position sensor, comprising:
- a magnetic component;
- a first magneto-resistive sensor disposed in proximity to the magnetic component;
- and
- a second magneto-resistive sensor disposed in proximity to the magnetic component and the first magneto-resistive sensor wherein the first magneto-resistive sensor and second magneto-resistive sensor are configured to sense changes, with a sub-nanoscale resolution, in a stray magnetic field created by the magnetic component in accordance with a relative positional change between the magnetic component and the first and second magneto-resistive sensors.
A position sensor, comprising:
- a magnetic component;
- a first magneto-resistive sensor disposed in proximity of the magnetic component;
- and
- a second magneto-resistive sensor disposed in proximity to the magnet and the first magneto-resistive sensor wherein the first magneto-resistive sensor and the second magneto-resistive sensor are arranged in a first direction having a gap between the first magneto-resistive sensor and the second magneto-resistive sensor where a position measurement is made along the first direction;
- the first magneto-resistive sensor and second magneto-resistive sensor are configured to sense changes in a stray magnetic field created by the magnetic component in accordance with a relative positional change between the magnetic component and the first and second magneto-resistive sensors in the first direction such that a position is measured by a differential signal which determines a difference between an output of the first magneto-resistive sensor and an output of the second magneto-resistive sensor.
A method for position sensing, comprising:
- providing a fixed component attached to a reference position, the fixed component including one of a magnetic component and a pair of magneto-resistive sensors;
- providing a positionable component on a movable platform, the positionable component including the other of the magnetic component and the pair of magneto-resistive sensors;
- sensing changes in a stray magnetic field created by a positional change between the fixed component and the positionable component;
- and
- subtracting the sensed changes of one of the pair of magneto-resistive sensors from sensed changes of the other of the pair of magneto-resistive sensors to measure the positional change.
Dependencies are inferred from the claim text.