Open AccessDesign of a noncooled fiber collimator for compact, high-efficiency fiber laser arrays
Author(s) -
L. A. Beresnev,
R. A. Motes,
Keith J. Townes,
Patrick Marple,
Kristan P. Gurton,
Anthony Valenzuela,
Chatt Williamson,
Jony J. Liu,
Chris Washer
Publication year - 2016
Publication title -
applied optics
Language(s) - English
Resource type - Journals
ISSN - 0003-6935
DOI - 10.1364/ao.56.00b169
Subject(s) - optics , collimator , collimated light , materials science , beam (structure) , gaussian beam , optical fiber , fiber laser , graded index fiber , beam parameter product , fiber , laser beam quality , laser , physics , fiber optic sensor , laser beams , composite material
A high-power fiber laser collimator and array of collimators are described with optical architecture, allowing one to transmit almost 100% of the full power output from fiber facets. In the case of coherent beam combining, more than 70% of the full power can be focused into a diffraction limited spot determined by the diameter of the conformal aperture. The truncated-Gaussian beam tails are not trapped inside the array but are redirected through the output lenses and dispersed outside of the array along with the main collimated beam, thus eliminating the requirement for cooling the array. Detailed analysis is presented for the beam tail propagation geometry's dependence on array optical parameters, including the interior redirecting lenses. The parasitic scattering from imperfections of the interior lenses is estimated to be as small as a few watts when 1.5-2 kW is emitted by each fiber facet.