Micro optic assemblies and optical interrogation systems

Patent metadata

Field	Value
Publication number	US-11499818-B2
Application number	US-202117190009-A
Country	US
Kind code	B2
Filing date	Mar 2, 2021
Priority date	Sep 27, 2016
Publication date	Nov 15, 2022
Grant date	Nov 15, 2022

Abstract

Example embodiments include an optical assembly for an optical interrogation system having a single core or a multicore sensing fiber, a measurement fiber to couple light into the sensing fiber, and a reference fiber arranged with the measurement fiber as part of an optical interferometer. A beam splitter combines light from the sensing fiber and with light from the reference fiber. A polarization beam splitting prism separates the combined light into first polarized light and second polarized light that is orthogonal to the first polarized light. The optical assembly can substantially reduce the size, complexity, or cost associated with the traditional optical components in an optical interrogation system that it replaces. Other example optical assemblies are described. Embodiments describe optical interrogation systems using the example optical assemblies.

First claim

What is claimed is:

1. An optical system, comprising:
an optical fiber configured to direct light emerging from the optical fiber as an expanding first beam;
a lens array configured to receive the expanding first beam and, in response to receiving the expanding first beam, produce a plurality of second beams; and
a monolithic optical assembly configured to receive the plurality of second beams to form a plurality of third beams inside the monolithic optical assembly, the monolithic optical assembly comprising a partial reflector configured to reflect a portion of each third beam of the plurality of third beams.

2. The optical system of claim 1 , wherein:
for each third beam of the plurality of third beams, the portion is about half of an optical power in that third beam of the plurality of third beams; and
the partial reflector is further configured to transmit about half of the optical power in each third beam of the plurality of third beams.

3. The optical system of claim 1 , wherein the monolithic optical assembly further comprises a lens configured to collimate each second beam of the plurality of second beams to form the plurality of third beams.

4. The optical system of claim 3 , wherein the lens comprises a plano-convex lens, the plano-convex lens bonded on a planar surface of the plano-convex lens to form the monolithic optical assembly.

5. The optical system of claim 3 , wherein:
the lens is a first lens; and
reflection of the portion of each third beam of the plurality of third beams by the partial reflector forms a plurality of fourth beams inside the monolithic optical assembly; and
the monolithic optical assembly further comprises a second lens configured to focus the plurality of fourth beams to form a plurality of foci, the plurality of foci located at a focal plane.

6. The optical system of claim 5 , wherein the first lens is oriented orthogonally to the second lens.

7. The optical system of claim 5 , further comprising a multi-core optical fiber having a plurality of cores and a longitudinal end located at the focal plane such that, for each focus, light from that focus is directed to:
enter a respective core of the plurality of cores,
propagate along a length of the multi-core optical fiber, and
reflect from a plurality of locations along the length of the multi-core optical fiber to form fifth beams that emerge from the longitudinal end.

8. The optical system of claim 7 , wherein:
the second lens is further configured to collimate the fifth beams to form a plurality of sixth beams; and
the sixth beams of the plurality of sixth beams propagate in the monolithic optical assembly.

9. The optical system of claim 8 , wherein:
the partial reflector is a first partial reflector;
the monolithic optical assembly further comprises a second partial reflector; and
the second partial reflector is configured to superimpose each sixth beam of the plurality of sixth beams with a corresponding seventh beam of a plurality of seventh beams to form a plurality of eighth beams.

10. The optical system of claim 9 , wherein:
the monolithic optical assembly further comprises a Wollaston prism;
the Wollaston prism is configured to separate each eighth beam of the plurality of eighth beams into a respective ninth beam and a respective tenth beam;
the ninth beams all have a same first polarization state; and
the tenth beams all have a second polarization state that is orthogonal to the same first polarization state.

11. The optical system of claim 10 , wherein:
the monolithic optical assembly further comprises a third lens;
the third lens is configured to focus the ninth beams to form eleventh beams outside of the monolithic optical assembly;
the third lens is further configured to focus the tenth beams to form twelfth beams outside of the monolithic optical assembly.

12. A method, comprising:
directing, with an optical fiber, light emerging from the optical fiber as an expanding first beam;
receiving the expanding first beam with a lens array to produce a plurality of second beams;
receiving the plurality of second beams with a monolithic optical assembly to form a plurality of third beams inside the monolithic optical assembly; and
reflecting a portion of each third beam of the plurality of third beams with a partial reflector of the monolithic optical assembly.

13. The method of claim 12 , further comprising:
collimating, with a lens of the monolithic optical assembly, each second beam of the plurality of second beams to form the plurality of third beams, the third beams of the plurality of third beams being substantially collimated and propagating in different directions from one another in the monolithic optical assembly.

14. The method of claim 13 , wherein the lens is a first lens, and wherein the method further comprises:
reflecting the portion of each third beam of the plurality of third beams with the partial reflector to form a plurality of fourth beams inside the monolithic optical assembly; and
focusing, with a second lens of the monolithic optical assembly, the fourth beams to form a plurality of foci at a focal plane.

15. The method of claim 14 , further comprising:
directing light from the plurality of foci into a multi-core optical fiber having a plurality of cores, the multi-core optical fiber having a longitudinal end located at the focal plane such that, for each focus of the plurality of foci, light from that focus enters a respective core of the plurality of cores, propagates along a length of the multi-core optical fiber, and reflects from a plurality of locations along the length of the multi-core optical fiber to form fifth beams that emerge from the longitudinal end.

16. The method of claim 15 , further comprising:
collimating the fifth beams with the second lens to form a plurality of sixth beams, the sixth beams of the plurality of sixth beams propagating in the monolithic optical assembly.

17. The method of claim 16 , wherein the partial reflector is a first partial reflector, the method further comprising:
superimposing, with a second partial reflector of the monolithic optical assembly, each sixth beam of the plurality of sixth beams with a corresponding seventh beam of a plurality of seventh beams to form a plurality of eighth beams.

18. The method of claim 17 , further comprising:
separating, with a Wollaston prism of the monolithic optical assembly, each eighth beam of the plurality of eighth beams into a respective ninth beam and a respective tenth beam, the ninth beams all having a same first polarization state, the tenth beams all having a second polarization state that is orthogonal to the same first polarization state.

19. An optical system, comprising:
an optical fiber configured to deliver light emerging from the optical fiber as an expanding first beam;
a lens array configured to receive the expanding first beam and, in response, produce a plurality of second beams; and
a monolithic optical assembly, the monolithic assembly including a collimating lens configured to collimate the plurality of second beams to form a plurality of collimated beams that propagate in the monolithic optical assembly, the monolithic assembly further including a focusing lens configured to focus the plurality of collimated beams to form a plurality of foci at a focal plane; and
a bundle of single-core fibers, each single-core fiber having a respective longitudinal end located at the focal plane and configured to receive light from a respective focus of the plurality of

Assignees

• Intuitive Surgical Operations

Inventors

• Froggatt Mark E
• Sanborn Eric E
• Sang Alexander K

Classifications

• G01B2290/70

  Using polarization in the interferometer · CPC title

• G02B5/04

  Prisms · CPC title

• G02B27/30

  Collimators · CPC title

• G01D5/3538

  using a particular type of fiber, e.g. fibre with several cores, PANDA fiber, fiber with an elliptic core or the like · CPC title

• G02B27/283

  used for beam splitting or combining · CPC title