Design of a noncooled fiber collimator for compact, high-efficiency fiber laser arrays.

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.