Magnetometer with light pipe

• US 9,817,081 B2
• Filed: 01/21/2016
• Issued: 11/14/2017
• Est. Priority Date: 01/21/2016
• Status: Active Grant

• Current Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Original Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Inventors: Hahn, Joseph W., Bruce, Gregory S., Huynh, Duc, Lew, Wilbur
• Primary Examiner(s): LEDYNH, BOT L
• Application Number:
  US15/003,281
• Publication Number:
  US 20170212178A1
• Time in Patent Office: 663 Days
• Field of Search: 3242441
• CPC Class Codes: G01J 1/0425 using optical fibers
• CPC Class Codes: G01R 33/0094 Sensor arrays
• CPC Class Codes: G01R 33/032 using magneto-optic devices, e.g. Faraday or Cotton-Mouton effect

Abstract

A device includes a diamond assembly. The diamond assembly includes a diamond with a plurality of nitrogen vacancy centers and electrical components that emit electromagnetic waves. The device also includes a light source configured to emit light toward the diamond and a photo detector configured to detect light from the light source that traveled through the diamond. The device further includes an attenuator between the diamond assembly and the photo detector. The attenuator is configured to attenuate the electromagnetic waves emitted from the electrical components of the diamond assembly.

Claims

1. A device comprising:

a diamond with a nitrogen vacancy;

a light source configured to transmit light toward the diamond;

a first sensor configured to sense a first portion of the light transmitted from the light source, wherein the first portion of the light does not travel through the diamond;

a second sensor configured to sense a second portion of the light transmitted from the light source, wherein the second portion of the light travels through the diamond;

a first light pipe configured to direct the second portion of the light from the diamond to the second sensor; and

a first waveguide cutoff filter surrounding the first light pipe that is configured to attenuate electromagnetic waves.

2. The device of claim 1, wherein the first light pipe comprises a first end surface, a second end surface, and a side wall surface, wherein the second portion of the light travels through the first end surface and through the second end surface, and wherein the second portion of the light does not travel through the side wall surface.

3. The device of claim 1, wherein the second sensor is located remotely from the diamond.

4. The device of claim 3, further comprising a circuit board surrounding at least a portion of the diamond, wherein the circuit board emits electromagnetic interference.

5. The device of claim 1, further comprising:

a third sensor configured to sense a third portion of the light, wherein the third portion of the light travels through the diamond to the third sensor;

a second light pipe configured to direct the third portion of the light from the diamond to the third sensor; and

a second waveguide cutoff filter surrounding the second light pipe.

6. The device of claim 5, wherein the first light pipe and the second light pipe are aligned along a central axis.

7. The device of claim 6, wherein the light source is configured to emit the second portion of the light and the third portion of the light in a direction that is perpendicular to the central axis.

8. The device of claim 5, wherein the first light pipe is located on an opposite side of the diamond as the second light pipe.

9. The device of claim 1, further comprising:

a third light pipe configured to direct the second portion of the light from the light source to the diamond; and

a third waveguide cutoff filter surrounding at least a portion of the third light pipe.

10. The device of claim 1, wherein the light source is configured to emit light that is substantially green.

11. The device of claim 1, wherein the light source comprises a laser device or a light emitting diode.

12. The device of claim 1, further comprising a red filter between the diamond and the first light pipe.

13. The device of claim 1, further comprising a red filter between the first light pipe and the second sensor.

14. The device of claim 1, wherein the first light portion comprises a first beam of light, and wherein the second light portion comprises a second beam of light.

15. The device of claim 1, further comprising a processor operatively coupled to the first sensor and the second sensor, wherein the processor is configured to:

receive, from the first sensor, a first signal indicating a strength of the first portion of the light with a first wavelength;

receive, from the second sensor, a second signal indicating a strength of the second portion of the light with a second wavelength; and

compare, based on the first signal and the second signal, the strength of the first portion of the light with the first wavelength and the strength of the second portion of the light with the second wavelength to determine a strength of a magnetic field applied to the diamond.

16. A device comprising:

a diamond with a nitrogen vacancy;

a light source configured to transmit light toward the diamond;

a first sensor configured to sense a first portion of the light transmitted from the light source, wherein the first portion of the light does not travel through the diamond;

a second sensor configured to sense a second portion of the light transmitted from the light source, wherein the second portion of the light travels through the diamond;

a light pipe configured to direct the second portion of the light from the light source to the diamond; and

a waveguide cutoff filter surrounding at least a portion of the light pipe.

17. A device comprising:

a diamond assembly comprising;

a diamond with a plurality of nitrogen vacancy centers, and

electrical components that emit electromagnetic waves;

a light source configured to emit light toward the diamond;

a photo detector configured to detect light from the light source that traveled through the diamond;

an attenuator between the diamond assembly and the photo detector, wherein the attenuator is configured to attenuate the electromagnetic waves emitted from the electrical components of the diamond assembly; and

a light pipe, wherein the attenuator surrounds at least a portion of the light pipe.

18. The device of claim 17, wherein the light pipe is configured to transfer light from the diamond to the photo detector.

19. The device of claim 17, wherein the light pipe and the attenuator are coaxial.

20. The device of claim 17, wherein the light pipe is tapered.

21. The device of claim 20, wherein a cross-sectional area of a first end of the light pipe is smaller than a cross-sectional area of a second end of the light pipe, and wherein the light enters the light pipe from the diamond at the first end.

22. The device of claim 17, wherein the light pipe has a diameter of between five millimeter and six millimeters.

23. The device of claim 17, wherein the attenuator comprises a metal.