Side firing fiber optic laser probe

• US 5,772,657 A
• Filed: 01/08/1997
• Issued: 06/30/1998
• Est. Priority Date: 04/24/1995
• Status: Expired due to Term

• Current Assignee: Lumenis Limited (Boston Scientific Corporation)
• Original Assignee: Coherent Inc (Coherent Corp.)
• Inventors: Manoukian, Nubar, Hmelar, Michael
• Primary Examiner(s): Lacyk, John P.
• Assistant Examiner(s): HUANG, STEPHEN D
• Application Number:
  US08/781,933
• Time in Patent Office: 538 Days
• Field of Search: 606/13-18, 606/7, 607/88, 607/89
• US Class Current: 606/15
• CPC Class Codes: A61B 18/22 the beam being directed along or through a flexible conduit, e.g. an optical fibre; Couplings or hand-pieces therefor
• CPC Class Codes: A61B 2018/2205 Characteristics of fibres
• CPC Class Codes: A61B 2018/2272 with reflective or refractive surfaces for deflecting the beam A61B2018/2261, A61B2018/2266 take precedence

Abstract

A side firing fiber optic probe is disclosed. The delivery end of the probe is provided with an angled face oriented to totally internally reflect the treatment beam out of the side surface of the fiber in a direction transverse to the longitudinal axis thereof. The delivery end of the probe is further configured to reduce secondary reflections which occur as the light strikes the side surface of the fiber. This result can be achieved by modifying the shape of the cladding material which surrounds the fiber core. In one approach, the ratio of the diameters of the clad to the core is increased. Other specific cladding configurations for reducing reflections can be used. In a further alternative, the surface of a glass capillary which surrounds the fiber can be optically coupled to the fiber. Each of these approaches functions to reduce unwanted light leakage from the fiber. In another aspect of the probe design, a stainless steel shield is provided which functions to protect the capillary and the fiber against cavitation effects which occur during use.

Claims

1. A fiber optic probe for delivering laser light comprising:

an optical fiber having an input end and a delivery end, with the delivery end including a means for redirecting light travelling down the fiber in a direction transverse to a longitudinal axis of the fiber in a manner to exit the fiber through a side surface thereof; and

said fiber includes a central core and an outer clad having a first radius of curvature, wherein a portion of the outer clad forming the side surface of the fiber is provided with a beam controlling surface to control at least one of divergence, convergence and collimation of the laser light passing through said side surface, said beam controlling surface having a second radius of curvature that is different than said first radius of curvature.

2. A probe as recited in claim 1 wherein the beam controlling surface is a planar surface.

3. A probe as recited in claim 1 wherein the beam controlling surface is a concave surface.

4. A probe as recited in claim 1 wherein the beam controlling surface is a convex surface.

5. A probe as recited in claim 1 wherein the delivery end of said optical fiber is tapered.

6. A probe as recited in claim 1 wherein:

the means for redirecting light is defined by a reflecting face disposed at a non-normal angle with respect to the longitudinal axis of the fiber to reflect the light travelling down the fiber by total internal reflection; and

the probe further including a transparent capillary sealingly mounted to the delivery end of the fiber and being configured such that a portion of an inner surface of the capillary adjacent the reflecting face of the fiber is spaced therefrom to define an air space therebetween and wherein a portion of the inner surface of the capillary adjacent the side surface of the fiber is optically coupled thereto so that an amount of light which is totally internally reflected at the side surface is reduced.

7. A probe as recited in claim 6 wherein the reflecting face is non-planar to alter the divergence of the light reflected thereby.

8. A probe as recited in claim 7 wherein the reflecting face is non-planar in one axis in a plane of the reflecting face and planar in an orthogonal axis to the one axis.

9. A probe as recited in claim 6 wherein said capillary is fused to said side surface to define the optical coupling.

10. A probe as recited in claim 6 wherein a transparent index matching material is provided between the capillary and the side surface to create optical coupling therebetween.

11. A fiber optic probe for delivering laser light comprising:

an optical fiber having an input end and a delivery end, with the delivery end including a reflecting face disposed at a non-normal angle with respect to a longitudinal axis of the fiber in a manner so that light travelling down the fiber will be reflected at the face and redirected in a direction transverse to the longitudinal axis of the fiber in a manner to exit the fiber through a side surface thereof; and

said fiber includes a central core and an outer clad having a first radius of curvature, wherein a portion of the outer clad forming the side surface of the fiber is provided with a beam controlling surface to control at least one of divergence, convergence and collimation of the laser light passing through said side surface, said beam controlling surface having a second radius of curvature that is different than said first radius of curvature.

12. A probe as recited in claim 11 wherein the beam controlling surface is a planar surface.

13. A probe as recited in claim 11 wherein the beam controlling surface is a concave surface.

14. A probe as recited in claim 11 wherein the beam controlling surface is a convex surface.

15. A probe as recited in claim 11 wherein:

the reflecting face is disposed to reflect the light travelling down the fiber by total internal reflection; and

said probe further including a transparent capillary sealingly mounted to the delivery end of the fiber and being configured such that a portion of an inner surface of the capillary adjacent the reflecting face of the fiber is spaced therefrom to define an air space therebetween and wherein a portion of the inner surface of the capillary adjacent the side surface of the fiber is optically coupled thereto so that an amount of light which is totally internally reflected at the side surface is reduced.

16. A probe as recited in claim 15 wherein said capillary is fused to said side surface to define the optical coupling.

17. A fiber optic probe for delivering laser light comprising:

an optical fiber having an input end and a delivery end, with the delivery end including a reflecting face disposed at a non-normal angle with respect to the longitudinal axis of the fiber;

a transparent capillary surrounding the delivery end of the fiber and creating an air pocket adjacent the reflecting face of the fiber so that light travelling down the fiber will be totally internally reflected at the angled face and redirected in a direction transverse to a longitudinal axis of the fiber in a manner to exit the fiber through a side surface thereof; and

a rigid, self-supporting, shield mounted to said fiber and surrounding at least a portion of the capillary along the side surface of the fiber, said shield including an opening to permit the transmission of light therethrough, said shield functioning to protect the capillary against destructive shockwave forces during use.

18. A probe as recited in claim 17 wherein said shield extends along a length of the fiber away from said reflecting face and beyond an end of the capillary in a manner to limit flexing of the fiber in a region adjacent the end of the capillary.

19. A probe as recited in claim 17 wherein said shield is formed from metal.

20. A probe as recited in claim 17 wherein said shield is formed from stainless steel.

21. A probe as recited in claim 17 further including a tubular member surrounding said fiber and adjacent an end of the capillary and wherein said shield extends over a portion of said tubular member as is connected thereto.

23. A probe as recited in claim 20 wherein the outer surface of the clad in a region of said side surface has a planar configuration.

24. A probe as recited in claim 20 wherein the outer surface of the clad in a region of said side surface has a concave configuration.

25. A probe as recited in claim 20 wherein the outer surface of the clad in a region of said side surface has a concave cylindrical configuration and where a longitudinal axis of the cylindrical configuration is parallel to the longitudinal axis of the core.

22. A fiber optic probe for delivering light comprising:

an elongated core for transmitting light, said core having an input end and a delivery end;

a clad surrounding the core;

means located at the delivery end of the core for redirecting the light travelling down the core in a direction transverse to a longitudinal axis of the core in a manner to exit the core and clad through side surfaces thereof, and wherein an outer surface of the clad in a region of said side surface including a non-convex curvature to alter a propagation path of the light transmitted therethrough.

26. A probe as recited in claim 22 wherein the outer surface of the clad in a region of said side surface has a concave cylindrical configuration and where a longitudinal axis of the cylindrical configuration is perpendicular to the longitudinal axis of the core.

27. A probe as recited in claim 22 wherein the means for redirecting light is defined by a reflecting face disposed at a non-normal angle with respect to the longitudinal axis of the core and wherein the probe further includes a transparent capillary sealingly mounted to the delivery end of probe and being configured such that a portion of an inner surface of the capillary adjacent the reflecting face of the core is spaced therefrom to define an air space therebetween and wherein a portion of the inner surface of the capillary adjacent the side surface of the clad is optically coupled thereto such that the clad and capillary function together to define said non-convex curvature.

28. A probe as recited in claim 27 wherein an outer surface of the capillary in a region of said side surface has a planar configuration.

29. A probe as recited in claim 27 wherein an outer surface of the capillary in a region of said side surface has a concave configuration.

30. A fiber optic probe for delivering laser light comprising:

an optical fiber having an input end and a delivery end, with the delivery end including a reflecting face disposed at a non-normal angle with respect to a longitudinal axis of the fiber in a manner so that light travelling down the fiber will be reflected at the face and redirected in a direction transverse to the longitudinal axis of the fiber in a manner to exit the fiber through a side surface thereof, said reflecting face is non-planar to alter at least one of divergence, convergence and collimation of the light reflected thereby.

31. A probe as recited in claim 30 wherein the reflecting face is non-planar in one axis in a plane of the reflecting face and planar in an orthogonal axis to the one axis.

32. A probe as recited in claim 30 further comprising:

a transparent capillary sealingly mounted to the delivery end of the fiber and being configured such that a portion of an inner surface of the capillary adjacent the reflecting face of the fiber is spaced therefrom to define an air space therebetween and wherein a portion of the inner surface of the capillary adjacent the side surface of the fiber is optically coupled thereto so that an amount of light which is totally internally reflected at the side surface is reduced.