Eye-safe Q-switched short pulse fiber laser

摘要

A laser includes a pump source that provides pump energy at a first wavelength and a laser cavity. The laser cavity includes a laser gain medium that receives the pump energy from the pump source and creates gain at a second wavelength different from the first wavelength, and a mode stripping portion coupled to the laser gain medium. The mode stripping portion causes the laser cavity to have a low Fresnel number so as to allow only the lowest-order fiber mode to resonate in the laser cavity. Higher-order fiber modes are discriminated against so as to generate a laser output having a substantially diffraction limited beam in a single transverse mode at the second wavelength.