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Jaroslaw Abramczyk

Kanishka Tankala

Kevin Farley

Clemence Jollivet

Michael Conroy

Upendra H Manyam

Bryce Neilson Samson

Martin Seifert

Nils Jacobson

Peyman Ahmadi

Douglas Guertin

Mansoor Alam

Eric Lim

The present disclosure relates more to mode mixing optical fibers useful, for example in providing optical fiber laser outputs having a desired beam product parameter and beam profile. In one aspect, the disclosure provides a mode mixing optical fiber for delivering optical radiation having a wavelength, the mode mixing optical fiber having an input end, an output end, a centerline and a refractive index profile, the mode mixing optical fiber comprising: an innermost core, the innermost core having a refractive index profile; and a cladding disposed about the innermost core, wherein the mode mixing optical fiber has at least five modes at the wavelength, and wherein the mode mixing optical fiber is configured to distribute a fraction of the light input at its input end from its lower-order modes to its higher-order modes.

Mode mixing optical fibers and methods and systems using the same

The present disclosure relates more to mode mixing optical fibers useful, for example in providing optical fiber laser outputs having a desired beam product parameter and beam profile. In one aspect, the disclosure provides a mode mixing optical fiber that includes a core having a refractive index profile; and a cladding disposed about the core. The core of the mode mixing optical fiber supports at least two (e.g., at least five) guided modes at the wavelength. The mode mixing optical fiber is configured to substantially distribute optical radiation having the wavelength propagating therein (e.g., input at its input end or generated or amplified within the core) among a plurality of the guided modes (e.g., to distribute a substantial fraction of the optical radiation having the wavelength propagating therein from its lower-order guided modes to its higher-order guided modes).

Optical apparatus () for providing light having a selected linear polarization having a polarization ratio, the apparatus () comprising a length of optical fiber () comprising a rare earth for providing light having a first wavelength responsive to receiving pump light having a second wavelength that is different than said first wavelength, wherein if the length of optical fiber () were placed in a first position between the length of fiber () is substantially linearly oriented () the fiber () could propagate at the first wavelength a fundamental mode and a plurality of higher order modes and the apparatus () could provide light having a first polarization ratio for the selected linear polarization and an Mparameter, and wherein the length of fiber () is positioned in a second position that increases the bend loss of the fiber relative to the first position such that, responsive to the increased bend loss, the apparatus () can provide light having a reduced Mparameter as well as a second polarization ratio for the selected polarization that is increased relative to the first polarization ratio, the increase being at least 6 dB greater than the first polarization ratio, and wherein when the length of fiber () is in the second position the apparatus () can provide a slope efficiency that is at least 50% of the ratio of the second wavelength to the first wavelength.

Method and apparatus for providing light having a selected polarization with an optical fiber

An optical fiber comprising a multimode glass core having a diameter of at least 250 microns and an index of refraction and a polymer cladding having a thickness and contactingly surrounding a glass portion of the fiber so as to define an interface between the glass portion and the polymer cladding. The polymer cladding can have a first index of refraction that is less than the index of refraction. The fiber can comprise a density of less than 0.25 non-conforming regions having a diameter of 25 microns or greater per millimeter of length along the fiber, where each of the non-conforming regions is a region visible to the human eye under an optical microscope and having at least a portion thereof within a selected distance of the interface. The selected distance can be less than or equal to the thickness of the polymer cladding. The optical microscope can have a total magnification of about 200. The polymer cladding can be applied to at least a part of the optical fiber in at least a class 1000 environment. Methods of using optical fibers, including receiving with an optical fiber optical energy from a source and guiding the optical energy with the optical fiber, wherein the optical energy comprises at least one of 1) pulses each comprising a peak power of at least 10 kW, 2) an average power of at least 50 Watts, or 3) an average power density of at least 2.9 kW/cm.

Optical fiber having reduced defect density

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Farmington, CT, United States of America

Jaroslaw Abramczyk