Opto-mechanical inertial sensor

• US 9,778,042 B2
• Filed: 12/13/2013
• Issued: 10/03/2017
• Est. Priority Date: 12/13/2013
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Bramhavar, Suraj, Hutchison, David N., Heck, John
• Primary Examiner(s): Caputo, Lisa
• Assistant Examiner(s): Sinha, Tarun
• Application Number:
  US14/106,158
• Publication Number:
  US 20160195397A1
• Time in Patent Office: 1,390 Days
• Field of Search: 7351426
• CPC Class Codes: G01C 19/56 Turn-sensitive devices using vibrating masses, e.g. vibratory angular rate sensors based on Coriolis forces
• CPC Class Codes: G01C 19/5719 using planar vibrating masses driven in a translation vibration along an axis
• CPC Class Codes: G01C 19/722 of the mechanical construction
• CPC Class Codes: G01D 5/35374 Particular layout of the fiber
• CPC Class Codes: G01P 15/093 by photoelectric pick-up
• CPC Class Codes: G01P 2015/084 the mass being suspended at more than one of its sides, e.g. membrane-type suspension, so as to permit multi-axis movement of the mass
• CPC Class Codes: G02B 6/4225 by a direct measurement of the degree of coupling, e.g. the amount of light power coupled to the fibre or the opto-electronic element

Abstract

Embodiments of the present disclosure are directed towards a micro-electromechanical system (MEMS) sensing apparatus, including a laser arrangement configured to generate a light beam, a first waveguide configured to receive and output the light beam, and a second waveguide aligned endface to endface with the first waveguide. The second waveguide may be configured to receive at least a portion of the light beam from the first waveguide via optical coupling through the aligned endfaces. Either the first or second waveguide may be configured to be moveable in response to an inertial change of the apparatus, wherein movement of the first or second waveguide causes a corresponding change in light intensity of the portion of the light beam, the change in light intensity indicating a measure of the inertial change. Other embodiments may be described and/or claimed.

Claims

1. A micro-electro-mechanical system (MEMS) apparatus, comprising:

a first waveguide; and

a second waveguide, substantially aligned endface to endface with the first waveguide, wherein at least a portion of the second waveguide is disposed on a movable proof mass structure, wherein one of the first or second waveguide is to receive at least a portion of the a light beam from another one of the first or second waveguide via optical coupling through the substantially aligned endfaces,

wherein a movement of the proof mass structure in response to an inertial change of the apparatus results in a shearing motion of the second waveguide relative to the first waveguide, such that a longitudinal axis of the at least a portion of the second waveguide is to move in the shearing motion relative to a longitudinal axis of the first waveguide whereby an endface of the first waveguide and an endface of the second waveguide are parallel during the shearing motion, and wherein movement of the endface of the second waveguide relative to a corresponding endface of the first waveguide that results from the movement of the longitudinal axis of the at least a portion of the second waveguide relative to the longitudinal axis of the first waveguide causes a corresponding change in light intensity of the portion of the light beam that indicates a measure of the inertial change.

2. The apparatus of claim 1, wherein the one of the first or second waveguide is a second waveguide, wherein the other one of the second or first waveguide is a first waveguide, wherein the endface of the second waveguide is a first endface, and is substantially aligned with the corresponding endface of the first waveguide, wherein the apparatus further comprises a third waveguide with an endface substantially aligned with a second endface of the second waveguide, wherein the third waveguide is to receive at least some of the portion of the light beam from the second waveguide via optical coupling through the substantially aligned endfaces of the second and third waveguides, wherein the proof mass is suspended between the first and third waveguides and is movable in response to the inertial change.

3. The apparatus of claim 1, further comprising:

a laser arrangement coupled with the one of the first or second waveguide, to generate the light beam, and a detector coupled with the other one of the first or second waveguide, to detect the change in light intensity of the portion of the light beam.

4. The apparatus of claim 1, wherein the first waveguide includes a number of additional endfaces through which to output portions of the light beam and the second waveguide is one of a corresponding number of waveguides, where individual waveguides, of the corresponding number of waveguides, are substantially aligned endface to endface with respective ones of the additional endfaces of the first waveguide, wherein the corresponding number of waveguides is to receive respective portions of the light beam via optical coupling with respective endfaces of the first waveguide.

5. The apparatus of claim 4, wherein the corresponding number of waveguides are to be moveable in the shearing motion.

6. The apparatus of claim 5, wherein the corresponding number of waveguides are coupled with respective detectors to detect changes in light intensity of the respective portions of the light beam to determine the inertial change.

7. The apparatus of claim 6, wherein the number of endfaces to output the light beam are spaced either fractionally closer together or fractionally farther apart than a spacing between the endfaces of the corresponding number of waveguides.

8. The apparatus of claim 7, wherein movement of either the number of endfaces of the first waveguide or the corresponding number of waveguides results in a decrease of light intensity of the portion of the light beam received by one of the individual waveguides and an increase in light intensity of the portion of the light beam received by another of the individual waveguides.

9. The apparatus of claim 8, wherein the one of the individual waveguides is adjacent to the another of the individual waveguides.

10. The apparatus of claim 9, wherein the increase of the light intensity received by the another of the individual waveguides is indicative of a direction of the inertial change of the apparatus.

11. The apparatus of claim 1, wherein the proof mass structure is movably affixed to a frame of the apparatus, such that the proof mass structure is movable in at least one direction relative to the frame, wherein a movement of the proof mass structure causes a change in an endface to endface alignment of the first waveguide and second waveguide.

13. The apparatus of claim 11, wherein an external acceleration of the frame causes the movement of the proof mass structure.

14. The apparatus of claim 13, wherein the apparatus comprises an accelerometer.

15. The apparatus of claim 11, wherein the proof mass structure is a first proof mass structure, wherein the laser arrangement and the first and second waveguides comprise a first assembly, wherein the apparatus further includes a second proof mass structure that is movably affixed to the frame such that the second proof mass structure is movable at least in another direction relative to the frame, wherein the another direction is perpendicular to the at least one direction.

16. The apparatus of claim 15, wherein the apparatus further includes a second assembly having components similar to those of the first assembly and disposed on the second proof mass structure.

17. The apparatus of claim 16, wherein the inertial change is a first inertial change, wherein an external rotation of the frame causes the movement of the second proof mass structure, wherein the movement of the second proof mass structure corresponds to a second inertial change, to be detected by the second assembly.

18. The apparatus of claim 17, wherein the second proof mass structure is disposed on the first proof mass structure.

19. The apparatus of claim 15, wherein the apparatus comprises a gyroscope.

12. The apparatus of clam 11, wherein the proof mass structure is affixed to the frame by at least two springs.

20. A method for detecting inertial change in an apparatus, comprising:

providing, by a light source generation unit of an apparatus, a light beam to a first waveguide, the first waveguide having an endface optically coupled with an endface of a second waveguide to cause the second waveguide to transmit at least a portion of the light beam, wherein at least a portion of one of the first or second waveguide is disposed on a proof mass structure that is moveable in a shearing motion in response to an inertial change of the apparatus, resulting in a movement of a longitudinal axis of the at least a portion of the one of the first or second waveguide in the shearing motion relative to a longitudinal axis of another one of the first or second waveguide, and in a correspondent movement of an endface of the one of the first or second waveguide in the shearing motion relative to a corresponding endface of the other one of the first or second waveguide whereby the endface of the first waveguide and the endface of the second waveguide are parallel during the shearing motion; and

detecting, by a detection module of the apparatus, in response to the inertial change of the apparatus, a change in light intensity of the portion of the light beam transmitted by the second waveguide, the change caused by the movement of the endface of the one of the first or second waveguide in the shearing motion relative to the corresponding endface of the other one of the first or second waveguide, respectively, the change indicating a measure of the inertial change of the apparatus.

21. The method of claim 20, wherein the inertial change includes at least one of external rotation or acceleration of the apparatus.

22. A computing device comprising:

a processor; and

a micro-electro-mechanical system (MEMS) apparatus coupled with the processor, the MEMS apparatus comprising;

a first waveguide;

a second waveguide, substantially aligned endface to endface with the first waveguide, wherein at least a portion of the second waveguide is disposed on a movable proof mass structure, wherein one of the first or second waveguide is to receive at least a portion of a light beam from another one of the first or second waveguide via optical coupling through the substantially aligned endfaces, wherein a movement of the proof mass structure in response to an inertial change of the computing device results in a shearing motion of the second waveguide relative to the first waveguide, such that a longitudinal axis of the at least a portion of the second waveguide is to move in the shearing motion relative to a longitudinal axis of the first waveguide, respectively, and wherein the movement of the second waveguide relative to the first waveguide causes a movement of an endface of the second waveguide relative to a corresponding endface of the first waveguide, which results in a change in light intensity of the portion of the light beam whereby the endface of the first waveguide and the endface of the second waveguide are parallel during the shearing motion; and

a detector coupled with the one of the first or second waveguide to detect the change in light intensity of the portion of the light beam and output a signal to the processor, the signal indicating a measure of light intensity, wherein the processor is to determine an inertial change of the computing device based upon the signal.

23. The computing device of claim 22, wherein the computing device is a mobile computing device selected from a group consisting of a laptop, netbook, notebook, ultrabook, smartphone, tablet, or personal digital assistant (PDA).

24. The computing device of claim 22, wherein the MEMS apparatus further comprises a laser arrangement to generate the light beam, wherein the laser arrangement is coupled with the other one of the first or second waveguide.