High Backscattering Waveguides

Abstract

A high backscattering fiber comprising a perturbed segment in which the perturbed segment reflects a relative power that is more than three (3) decibels (dB) above Rayleigh scattering. The high backscattering fiber also exhibits a coupling loss of less than 0.5 dB.

What is claimed is: 
     
         1 . An optical fiber having a modified index caused by applying a spatial pattern that creates a refractive index perturbation, the optical fiber comprising:
 a perturbed segment having an index perturbation that causes backscattering that is more than three (3) decibels (dB) above Rayleigh scattering; and   a mode effective area that is no smaller than that of a standard single-mode fiber, the standard single-mode fiber being a G.652-compliant optical fiber.   
     
     
         2 . An optical fiber having a modified index caused by applying a spatial pattern that creates a refractive index perturbation, the optical fiber comprising:
 a perturbed segment having an index perturbation that causes backscattering that is more than ten (10) decibels (dB) above Rayleigh scattering;   a mode effective area that is no smaller than that of a standard single-mode fiber, the standard single-mode fiber being a G.652-compliant optical fiber.   
     
     
         3 . An optical fiber having a modified index caused by applying a spatial pattern that creates a refractive index perturbation, the optical fiber comprising:
 a perturbed segment having an index perturbation that causes backscattering that is greater than Rayleigh scattering; and   a mode effective area that is no smaller than that of a standard single-mode fiber.   
     
     
         4 . The fiber of  claim 3 , wherein the standard single-mode fiber is a G.652-compliant optical fiber. 
     
     
         5 . The fiber of  claim 3 , further comprising a nonlinearity that is no greater than that of the standard single-mode fiber. 
     
     
         6 . The fiber of  claim 3 , wherein the backscattering caused by the index perturbation is more than three (3) decibels (dB) above Rayleigh scattering. 
     
     
         7 . The fiber of  claim 3 , wherein the backscattering caused by the index perturbation is more than ten (10) decibels (dB) above Rayleigh scattering.