Optomechanical inertial sensor

• US 9,285,391 B2
• Filed: 12/13/2013
• Issued: 03/15/2016
• Est. Priority Date: 12/13/2013
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Hutchison, David N., Heck, John
• Primary Examiner(s): Lyons, Michael A
• Assistant Examiner(s): DECENZO, SHAWN H
• Application Number:
  US14/106,259
• Publication Number:
  US 20150168442A1
• Time in Patent Office: 823 Days
• US Class Current: 1/1
• CPC Class Codes: G01B 9/02023 Indirect probing of object, e.g. via influence on cavity or fibre
• 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 19/5712 the devices involving a micromechanical structure
• CPC Class Codes: G01C 19/5733 Structural details or topology
• CPC Class Codes: G01C 19/5776 Signal processing not specific to any of the devices covered by groups G01C19/5607 - G01C19/5719
• CPC Class Codes: G01P 15/093 by photoelectric pick-up
• CPC Class Codes: G01P 2015/0848 using a plurality of mechanically coupled spring-mass systems, the sensitive direction of each system being different

Abstract

Embodiments of the present disclosure are directed towards techniques and configurations for MEMS sensing device configured to determine inertial change applied to the device. In one instance, the device may comprise a laser arrangement configured to generate a light beam, and a waveguide configured to split the light beam into two portions. The waveguide may include two arms through which the respective portions of the light beam may respectively pass, and disposed substantially parallel with each other and joined together around their respective ends to recombine the portions into a light beam. One of the arms may be deformable. A deformation of the arm may result in a change of an optical path length of a portion of the light beam traveling through the arm, causing a detectable change in light intensity of the recombined light beam outputted by the waveguide. Other embodiments may be described and/or claimed.

Claims

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

a laser arrangement to generate a light beam;

a waveguide substantially disposed in a frame to split the light beam into a first and second portions, the waveguide including a first arm and a second arm through which the first and second portions of the light beam are to respectively pass, the first and second arms disposed substantially parallel with each other and joined together around respective ends of each arm to recombine the first and second portions into a recombined light beam, wherein the first arm is to be deformable; and

a proof mass attached to the first arm independently from the second arm and movably affixed to the frame,

wherein the proof mass is to move along a substantially straight line in a substantially perpendicular direction relative to the waveguide disposed in the frame and to the second portion of the light beam passing through the second arm, wherein the first arm is to deform in response to a movement of the first proof mass that occurs in response to inertial change associated with the apparatus, while the second arm remains free of deformation, wherein a deformation of the first arm results in a change of an optical path length of a portion of the light beam traveling through the first arm, causing a detectable change in light intensity of the recombined light beam outputted by the waveguide.

2. The apparatus of claim 1, further comprising a phase shifter coupled with the second arm and to provide a phase shift to the second portion of the light beam relative to the first portion of the light beam.

3. The apparatus of claim 1, further comprising a detector coupled to the waveguide to detect the change in light intensity of the light beam outputted by the waveguide.

4. The apparatus of claim 3, further comprising circuitry coupled to the detector to determine the inertial change associated with the apparatus based on the detected change in light intensity.

5. The apparatus of claim 4, wherein the proof mass attached to the first arm is a first proof mass;

and wherein the first proof mass is to move in the substantially perpendicular direction relative to the waveguide.

6. The apparatus of claim 5, wherein the first proof mass is movable at least in one direction relative to the frame, wherein an external acceleration of the frame causes the inertial change that causes movement of the first proof mass.

7. The apparatus of claim 6, wherein the apparatus comprises a first assembly, wherein the apparatus further includes a second assembly comprising:

another waveguide to further split the light beam into a third and fourth portions, the waveguide including a third arm and a fourth arm through which the third and fourth portions of the light beam are to respectively pass, the third and fourth arms disposed substantially parallel with each other and joined together around respective ends of each arm to recombine the third and fourth portions into another recombined light beam, wherein the third arm is to be deformable;

wherein a deformation of the third arm results in a change of an optical path length of a portion of the light beam traveling through the third arm, causing a detectable change in light intensity of the recombined light beam outputted by the waveguide.

8. The apparatus of claim 7, further comprising a second proof mass attached to the third arm, wherein the deformation of the third arm is caused by a movement of the proof mass in response to an external rotation applied to the apparatus.

9. The apparatus of claim 8, wherein the second proof mass is disposed on the first proof mass.

10. The apparatus of claim 9, wherein the first proof mass is attached to the frame with a first spring arrangement, wherein the second proof mass is attached to the first proof mass with a second spring arrangement.

11. The apparatus of claim 1, wherein the first arm comprises a substantially S-shaped bend, wherein the deformation of the first arm in one direction comprises lengthening of the first arm, and the deformation of the first arm in an opposite direction comprises shortening of the first arm.

12. The apparatus of claim 1, wherein the apparatus is integrated in a chip.

13. The apparatus of claim 12, wherein the chip is integrated in a computing device.

14. A method, comprising:

detecting a change in light intensity of a recombined light beam outputted by a waveguide of a micro-electromechanical system (MEMS) apparatus, the waveguide substantially disposed in a frame and comprising a first arm through which a first portion of a light beam inputted in the waveguide passes and a second arm through which a second portion of the light beam passes, the first and second arm disposed substantially parallel with each other and joined together around respective ends of each arm to recombine the first and second portions into the recombined light beam, wherein the first arm is to be deformable; and

determining an inertial change associated with the apparatus based on the detected change in light intensity, the detected change occurring in response to a deformation of the first arm caused by a movement of a proof mass attached to the first arm independently from the second arm, in response to inertial change associated with the apparatus, while the second arm remains free of deformation, the proof mass moving along a substantially straight line in a substantially perpendicular direction relative to the waveguide disposed in the frame and to the second portion of the light beam passing through the second arm.

15. The method of claim 14, further comprising:

tuning a first wavelength of the first portion of the light beam relative to a second wavelength of the second portion of the light beam to provide the recombined light beam having a wavelength corresponding to a determined value of a sine curve formed by the recombined light beam before the detecting the change in light intensity of the recombined light beam.

16. The method of claim 14, wherein the inertial change is caused by an external acceleration of the apparatus.

17. The method of claim 16, wherein the first arm comprises an S-shaped bend, wherein the deformation of the first arm in one direction comprises lengthening of the first arm, and the deformation of the first arm in an opposite direction comprises shortening of the first arm, wherein the method further comprises:

determining whether a length of the first arm increased or decreased; and

identifying a direction of movement of the proof mass, based on a result of the determining.

18. The method of claim 17, further comprising:

determining a direction of an external acceleration based on a result of identifying.