Corning Incorporated

Robert Arnold Knowlton

Ji Wang

Pushkar Tandon

Scott Robertson Bickham

Luis Alberto Zenteno

Donnell Thaddeus Walton

Joseph Edward McCarthy

Ronald L Kimball

Dana Craig Bookbinder

Ming-Jun Li

Steven Bruce Dawes

Kevin Wallace Bennett

Kimberly Wilbert Smith

According to embodiments, an optical fiber may include a core portion comprising a radius r, a centerline C, a numerical aperture NA greater than or equal to 0.15 and less than or equal to 0.25, a graded relative refractive index profile having a maximum relative refractive index &#x394;and an &#x3b1; value greater than or equal to 1 and less than or equal to 3. The core portion may include an up-dopant with a graded concentration from the radius rto the centerline Cand an attenuation dopant with a constant concentration from the centerline Cof the core portion to the radius rof the core portion. The optical fiber is multi-moded for wavelengths of light within a range from 800 nm to 1350 nm and an attenuation of the optical fiber wavelengths between 800 nm and 1000 nm is greater than or equal to 0.5 dB/m.

Multimode optical fibers for attenuators

Methods for forming optical fiber preforms with low-index trenches are disclosed. According to one embodiment, the method includes depositing silica-based glass soot on a bait rod to form a low-index trench region of the optical fiber preform. The silica-based glass soot is deposited such that the low-index trench region has a first density. Thereafter a barrier layer having a second density greater than the first density is formed around the low-index trench region. Therafter, an overclad region is deposited around the barrier layer. The bait rod is then removed from a central channel of the trench-overclad assembly. A separate core assembly is inserted into the central channel. A down-dopant gas is then directed through the central channel of the trench-overclad assembly as the trench-overclad assembly is heated to dope the low-index trench region. The barrier layer prevents diffusion of the down-dopant from the low-index trench region into the overclad region.

Methods for producing optical fiber preforms with low index trenches

A multimode optical fiber, and a method of making the fiber, are provided according to the following steps and elements: forming a core preform with a graded refractive index that includes silica and an up-dopant; drawing the core preform into a core cane; forming an inner annular segment preform that includes silica soot and an up-dopant surrounding the core cane; and forming a depressed-index annular segment preform that includes silica soot surrounding the inner annular segment preform. The method also includes the steps: forming an outer annular segment preform that includes silica soot and an up-dopant surrounding the depressed-index annular segment preform; doping the inner, depressed-index and outer annular segment preforms simultaneously or nearly simultaneously with a down-dopant; and consolidating the segment preforms simultaneously or nearly simultaneously into inner, depressed-index and outer annular segments.

High bandwidth MMF and method of making

According to one example of the invention an optical fiber comprises: (i) silica based, rare earth doped core having a first index of refraction n; (ii) at least one silica based cladding surrounding the core and having a second index of refraction n, such that n&#x3e;n; wherein at least one of the core or cladding is doped with AlO, such that the ratio of max wt % to min wt % of AlOconcentration is less than 2:1.

Optical fiber and method for making such fiber

Growing community of inventors

Wellsboro, PA, United States of America

Robert Arnold Knowlton