Fiber optic probe tip

Abstract

The invention described here is an improved fiber optic probe and methods of making such fiber optic probe. The tip of the probe is made from a transparent fill material that is connected to the end of a conventional optical fiber. The optical fiber is tapered, the fill material is connected thereto, and typically extends outwardly from the fiber as though it is a continuous part of the fiber. The outer diameter of the fill material is preferably essentially the same as the optical fiber. The fill material may contain light-scattering elements that disperse light as it exits the fiber.

1 . A method of forming a fiber optic probe, comprising:
 providing an optical fiber having an outer diameter wherein the optical fiber is surrounded by a covering and the optical fiber includes a tapered end; and   providing a terminal material at the end of the optical fiber for forming a probe tip such that:
 i. the terminal material has an outer diameter that is substantially the same as the outer diameter of the optical fiber; 
 ii. the terminal material is connected to the tapered end and extends outwardly from the tapered end; 
 iii. the terminal material is made of a material different from the material of the optical fiber; and 
 iv. the tip is exposed and allows for lateral dispersion of light from the tapered end as scattered by the fill material. 
   
   
   
       2 . A method as in  claim 1  wherein the step of providing the optical fiber includes forming the end of the optical fiber such that the end is recessed into the cladding for forming a hollow space. 
   
   
       3 . A method as in  claim 2  wherein forming of the end of the optical fiber is accomplished by etching an end of the optical fiber. 
   
   
       4 . A method as in  claim 2  wherein the hollow space surrounds the end of the optical fiber. 
   
   
       5 . A method as in  claim 2  wherein the step of providing the terminal material includes providing the terminal material to the hollow space such that the terminal material is at least partially located in front of the optical fiber. 
   
   
       6 . A method as in  claim 5  wherein provision of the terminal material to the hollow space includes:
 i. forming an orifice in the covering for providing access to the hollow space; and   ii. providing terminal material to the hollow space by drawing the terminal material as a relatively viscous liquid into the hollow space under vacuum pressure through the orifice.   
   
   
       7 . A method as in  claim 1  further comprising stripping at least a portion of the covering away from the terminal material leaving the terminal material with the outer diameter substantially the same as the outer diameter of the optical fiber. 
   
   
       8 . A method as in  claim 1  further comprising curing and/or hardening the terminal material. 
   
   
       9 . A method as in  claim 1  wherein the terminal material extends coaxially outwardly with the end of the optical fiber. 
   
   
       10 . A method as in  claim 1  wherein the terminal material is provided such that it at least partially surrounds the end of the optical fiber. 
   
   
       11 . A method as in  claim 1  wherein the end of the optical fiber is conical in shape. 
   
   
       12 . A method as in  claim 1  wherein the covering covers the probe at least adjacent a region where the optical fiber and terminal material are connected together. 
   
   
       13 . A method as in  claim 1  wherein the covering is a cladding. 
   
   
       14 . A method as in  claim 13  wherein the cladding is formed of a polymeric material. 
   
   
       15 . A method as in  claim 1  wherein the terminal material has at least one light-scattering element. 
   
   
       16 . A method as in  claim 1  wherein the terminal material includes a plurality of light-scattering elements or has inherent light scattering elements. 
   
   
       17 . A method as in  claim 1  wherein the terminal material includes a plurality of light-scattering elements that comprise TiO 2 . 
   
   
       18 . A method as in  claim 1  wherein the terminal material has a rounded end. 
   
   
       19 . A method as in  claim 1  wherein the terminal material is a curable epoxy material that includes titanium light scattering elements. 
   
   
       20 . A method as in  claim 1  wherein the probe is configured for performing photodynamic therapy. 
   
   
       21 . A method in  claim 1  wherein the outer diameter of the terminal material surrounds the tapered end and the outer diameter of the terminal material is less than an outer diameter of the covering. 
   
   
       22 . A method of using a fiber optical probe for performing photodynamic therapy comprising:
 Applying a photosensitizing compound to the desired treatment area; and   Activating the photosensitizing compound by applying electromagnetic radiation delivered by a fiber optic probe comprising:   an optical fiber having an outer diameter and a tapered end, the tapered end providing a surface area;   a terminal material that is made of a material different from the material of the optical fiber wherein:
 i. the terminal material is connected to and located in front of the tapered end of the optical fiber, the terminal material being bonded to the surface area of the tapered end; and 
 ii. the terminal material has an outer diameter that is substantially the same as the outer diameter of the optical fiber; and 
   a cladding surrounding the optical fiber and covering the probe at a region where the optical fiber and the terminal material are connected together;   wherein the terminal material includes a plurality of light-scattering elements or has inherent light scattering elements.