Sensor for measuring a magnetic field

Patent metadata

Field	Value
Publication number	US-11719765-B2
Application number	US-202217739066-A
Country	US
Kind code	B2
Filing date	May 6, 2022
Priority date	Jun 4, 2021
Publication date	Aug 8, 2023
Grant date	Aug 8, 2023

Abstract

An embodiment of the invention relates to a sensor comprising a sensor element (10) for measuring a magnetic field, the sensor element (10) comprising a set of at least two first input ports (I1), a set of at least two exit ports (E) each of which is connected to one of the first input ports (I1) via a corresponding first beam path (B1), a set of at least two second input ports (I2) each of which is connected to a second beam path (B2), wherein the first beam paths (B1) extend through a common plane (CP) located inside the sensor element (10), said plane (CP) comprising a plurality of magneto-optically responsive defect centers, wherein the second beam paths (B2) also extend through said common plane (CP), but are angled with respect to the first beam paths (B1) such that a plurality of intersections between the first and second beam paths (B2) is defined, and wherein each intersection forms a sensor pixel (P) located at at least one of said magneto-optically responsive defect centers.

First claim

The invention claimed is:

1. Sensor comprising a sensor element ( 10 ) for measuring a magnetic field, the sensor element ( 10 ) comprising
a set of at least two first input ports (I 1 ),
a set of at least two exit ports (E) each of which is connected to one of the first input ports (I 1 ) via a corresponding first beam path (B 1 ),
a set of at least two second input ports (I 2 ) each of which is connected to a second beam path (B 2 ),
wherein the first beam paths (B 1 ) extend through a common plane (CP) located inside the sensor element ( 10 ), said plane (CP) comprising a plurality of magneto-optically responsive defect centers,
wherein the second beam paths (B 2 ) also extend through said common plane (CP), but are angled with respect to the first beam paths (B 1 ) such that a plurality of intersections between the first and second beam paths (B 2 ) is defined, and
wherein each intersection forms a sensor pixel (P) located at at least one of said magneto-optically responsive defect centers.

2. Sensor of claim 1 wherein
the first beam paths (B 1 ) are parallel,
the second beam paths (B 2 ) are parallel, and
the first beam paths (B 1 ) are perpendicular to the second beam paths (B 2 ) such that the intersections form a two-dimensional array of sensor pixels (P).

3. Sensor of claim 1 further comprising
a set of detectors ( 20 ) each of which is individually assigned to one of said exit ports,
an evaluation unit ( 30 ) connected to said set of detectors ( 20 ) and configured to evaluate detection signals (DS) of the detectors ( 20 ) in order to generate one or more measurement values (M),
a first emitter unit ( 40 ) which is capable of generating a first radiation (R 1 ) and activating at least one of the first beam paths (B 1 ) by injecting the first radiation (R 1 ),
a second emitter unit ( 50 ) which is capable of generating a second radiation (R 2 ) and activating at least one of the second beam paths (B 2 ) by injecting the second radiation (R 2 ),
a control unit ( 60 ) configured to control the first and second emitter unit ( 40 , 50 ), and
a microwave generator ( 70 ) capable of generating a microwave field at the intersection points of the beam paths (B 1 , B 2 ).

4. Sensor of claim 3 wherein
the control unit ( 60 ) is configured to control the second emitter unit ( 50 ) such that maximally one of the second beam paths (B 2 ) is provided with the second radiation (R 2 ) in each moment of time.

5. Sensor of claim 3 wherein
the control unit ( 60 ) is configured to control the first emitter unit ( 40 ) to input the first radiation (R 1 ) into all of the first beam paths (B 1 ) simultaneously, and
the evaluation unit ( 30 ) is configured to evaluate the detection signals (DS) of the detectors ( 20 ) simultaneously in order to generate simultaneously measurement values (M) for all first beam paths (B 1 ).

6. Sensor of claim 3 further comprising
a printed circuit board ( 100 ) located on top of the sensor element ( 10 ) or below the sensor element ( 10 ) and providing at least one coil ( 71 ),
wherein the microwave generator ( 70 ) is configured to provide a microwave signal to said at least one coil ( 71 ) to generate a microwave field in the sensor element ( 10 ).

7. Sensor of claim 6 wherein
said printed circuit board ( 100 ) comprises a plurality of coils ( 71 ) each of which is assigned to one of the intersections, and
each of the intersections is provided with a microwave field generated by the individually assigned coil ( 71 ).

8. Sensor of claim 1 further comprising
a carrier ( 100 ) on which the sensor element ( 10 ) is mounted,
wherein the carrier ( 100 ) provides at least one groove that carries a fiber ( 120 ), and
wherein said fiber ( 120 ) connects one of the input ports (I 1 , I 2 ) with the first or second emitter unit ( 40 , 50 ), or connects one of the exit ports (E) with one of the detectors ( 20 ).

9. Sensor of claim 1 further comprising
a carrier ( 100 ) on which the sensor element ( 10 ) is mounted,
wherein at least one of the first and second emitter units ( 40 , 50 ) comprises an emitter element that is mounted on the carrier ( 100 ) and individually assigned to one of the input ports, and/or
wherein at least one of the detectors ( 20 ) is mounted on the carrier ( 100 ).

10. Sensor of claim 8 wherein
at least one lens ( 130 ) is mounted on the carrier ( 100 ) between one of the input ports (I 1 , I 2 ) and the respective fiber ( 120 ), between one of the emitter elements ( 40 , 50 ) and the respective input port (I 1 , I 2 ), or between one of the exit ports (E) and the respective detector ( 20 ).

11. Sensor of claim 1 wherein
at least one of the first or second beam paths (B 2 ) is provided with a waveguide that is integrated in the sensor element ( 10 ) and guides the radiation through said common plane (CP).

12. Sensor of claim 1 wherein
reflection zones may be provided that allow the radiation to pass the beams paths at least twice.

13. Sensor of claim 1 wherein
the sensor comprises a pixel position control unit capable of varying the positions and/or directions of the beam paths and therefore vary the positions of the intersections.

14. Method of measuring a magnetic field using a sensor according to claim 1 , the method comprising the steps of
injecting a first radiation (R 1 ) into at least one of the first beam paths (B 1 ),
injecting a second radiation (R 2 ) into at least one of the second beam paths (B 2 ),
generating a microwave field at least at the intersection point where the at least one of the first beam paths (B 1 ) and at the least one of the second beam paths (B 2 ) intersect,
detecting the first radiation (R 1 ), and
evaluating the detected radiation and generating one or more measurement values (M) that describe the magnetic field at the intersection or intersections where the first and second radiation (R 2 ) intercept.

15. Method of claim 14
wherein the first radiation (R 1 ) is simultaneously injected into all of the first beam paths (B 1 ), and the second radiation (R 2 ) is injected into a single one of the second beam paths (B 2 ), and
measurement values (M) are generated for each of the sensor pixels (P) that belong to the activated second beam path (B 2 ).

16. Method of claim 14 wherein evaluating the detected radiation and generating one or more measurement values (M) includes measuring the absorption of the first radiation (R 1 ).

17. Method of claim 15 wherein evaluating the detected radiation and generating one or more measurement values (M) includes measuring the absorption of the first radiation (R 1 ).

Assignees

• Humboldt Univ Zu Berlin
• Fraunhofer Ges Forschung

Inventors

• Schröder Tim
• Perona Martinez Felipe
• Bopp Julian
• Kleinert Moritz
• Conradi Hauke

Classifications

• G01R33/032 Primary

  using magneto-optic devices, e.g. Faraday {or Cotton-Mouton effect} · CPC title

• G01R33/0206

  Three-component magnetometers · CPC title

• G01R33/26 Primary

  using optical pumping · CPC title

• G01R33/323

  Detection of MR without the use of RF or microwaves, e.g. force-detected MR, thermally detected MR, MR detection via electrical conductivity, optically detected MR · CPC title

• G01R33/0094

  Sensor arrays · CPC title