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Updated: Jan 30, 2026
11:27
Magnetically-Assisted Remote Controlled Microcatheter Tip Deflection under Magnetic Resonance Imaging
Published on: April 4, 2013
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Dual Resonator MEMS Magnetic Field Gradiometer
Matthias Kahr1, Michael Stifter2, Harald Steiner3
1Department for Integrated Sensor Systems, Danube University Krems, 2700 Wiener Neustadt, Austria. matthias.kahr@donau-uni.ac.at.
Sensors (Basel, Switzerland)
|January 30, 2019
Summary
This study presents a microelectromechanical systems (MEMS) magnetic field gradiometer for precise spatial magnetic field measurements. The novel sensor offers a compact, low-cost solution for accurately determining magnetic flux density and field gradients.
Area of Science:
- Physics
- Electrical Engineering
- Materials Science
Background:
- Accurate spatial magnetic field distribution knowledge is crucial for field gradient measurements.
- Existing methods may lack the precision or compactness required for certain applications.
Purpose of the Study:
- To report a novel microelectromechanical systems (MEMS) magnetic field gradiometer.
- To enable simultaneous measurement of magnetic flux density at two points for local field gradient evaluation.
Main Methods:
- Fabrication of a MEMS gradiometer with two independent, laterally oscillating masses on a single chip.
- Actuation via Lorentz force and optical readout by modulating light flux through stationary and moving arrays.
- Recording both phase and intensity for magnetic field uniformity assessment.
Main Results:
- Characterization at ambient pressure yielded a responsivity of 35.67 V/T.
- A detection limit of 3.07 µT/√Hz (@ 83 Hz ENBW) was achieved.
- Demonstrated simultaneous measurement of magnetic flux density at two spatial points.
Conclusions:
- The developed MEMS magnetic field gradiometer provides accurate local field gradient evaluation.
- The sensor is compact, offers a large dynamic range, and is potentially low-cost due to MEMS batch fabrication.
- Optical readout decouples the transducer from electronics, enhancing stability and performance.
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