Bend Resistant Multimode Optical Fiber

Abstract

Bend resistant multimode optical fibers are disclosed herein. Multimode optical fibers disclosed herein comprise a core region and a cladding region surrounding and directly adjacent to the core region, the cladding region comprising a depressed-index annular portion comprising a depressed relative refractive index.

1 - 33 . (canceled) 
     
     
         34 . A multimode optical fiber comprising:
 a graded index glass core; and   a glass cladding surrounding and in contact with the core, the cladding comprising a depressed-index annular portion wherein the depressed-index annular region is offset from said core by at least 0.4 microns;   wherein the core has a maximum relative refractive index Δ1MAX, in %, at 850 nm;   wherein the core and the cladding provide (a) a bandwidth of greater than greater than 3.0 GHz-km at a wavelength of 850 nm.   
     
     
         35 . The optical fiber of claim  1 , further comprising a core radius greater than 20 microns and less than 28. 
     
     
         36 . The optical fiber of claim  1 , further comprising a 1 turn 10 mm diameter mandrel wrap attenuation increase at a wavelength of 1550 nm, in dB, of less than or equal to the product of two times (1/Δ1MAX) 2 . 
     
     
         37 . The optical fiber of claim  1 , further comprising a 1 turn 10 mm diameter mandrel wrap attenuation increase at a wavelength of 850 nm of less than 1.5 dB. 
     
     
         38 . The optical fiber of claim  1 , further comprising a 1 turn 10 mm diameter mandrel wrap attenuation increase at a wavelength of 850 nm of less than 1.0 dB. 
     
     
         39 . The optical fiber of claim  1 , further comprising a 1 turn 10 mm diameter mandrel wrap attenuation increase at a wavelength of 850 nm of less than 0.62 dB. 
     
     
         40 . The optical fiber of claim  1 , further comprising a profile volume with an absolute magnitude of greater than 50%-μm 2 . 
     
     
         41 . The optical fiber of claim  1 , wherein the core comprises germania doped silica. 
     
     
         42 . The optical fiber or claim  6 , wherein the depressed-index annular region of the cladding comprises fluorine. 
     
     
         43 . The optical fiber or claim  1 , wherein the depressed-index annular portion has profile volume with an absolute magnitude of less than 200%-μm 2 . 
     
     
         44 . A multimode optical fiber comprising:
 a graded index glass core, the outer radius R 1  of said core ending where the graded index region of the core ends, wherein 12.5≦R 1 ≦40 microns; and   
       a glass cladding surrounding and in contact with the core, the cladding comprising a depressed-index annular portion surrounding and in contact with the core and an outer cladding region surrounding the depressed cladding region. 
     
     
         45 . The optical fiber of claim  11 , further comprising a 1 turn 10 mm diameter mandrel wrap attenuation increase at a wavelength of 850 nm of less than 1.5 dB. 
     
     
         46 . The optical fiber of claim  11 , further comprising a 1 turn 10 mm diameter mandrel wrap attenuation increase at a wavelength of 850 nm of less than 1.0 dB. 
     
     
         47 . The optical fiber of claim  11 , further comprising a 1 turn 10 mm diameter mandrel wrap attenuation increase at a wavelength of 850 nm of less than 0.62 dB. 
     
     
         48 . The optical fiber of claim  11 , further comprising a profile volume with an absolute magnitude of greater than 50%-μm 2 . 
     
     
         49 . The optical fiber of claim  11 , wherein the core comprises germania doped silica. 
     
     
         50 . The optical fiber or claim  16 , wherein the depressed-index annular region of the cladding comprises fluorine. 
     
     
         51 . The optical fiber or claim  11 , wherein the depressed-index annular portion has profile volume with an absolute magnitude of less than 200%-μm 2 .