High brightness fiber coupled modular diode laser platform

Abstract

High-power and high-brightness fiber coupled diode laser devices are in demand in two main commercial applications. The largest is for solid-state laser pumping, especially the fiber laser market, where the push to higher power fiber lasers is driving the need for bright, high power pump sources. The other market is for direct diode laser material processing, eliminating the use of a "beam quality converter" such as fiber lasers or disc lasers. Without the need for solid state laser beam conversion, a direct diode laser beam is, in principle, more efficient and smaller, but the combined multiple beams from hundreds of individual emitters requires beam shaping and lensing at the expense of efficiency and the module's brightness is confined within the limits of the beam quality of the diode lasers. When the costs for the micro-optical elements and their handling and alignment are considered, the assumption of the economic superiority over solid state laser sources is not so readily apparent.