Double-cutting beam shaping technique for high-power diode laser area light source

A new beam-shaping technique is proposed to improve the beam quality of a high-power diode laser area light source. It consists of two staggered prism arrays and a reflector array, which can cut the slow axis beam twice and rearrange the divided beams in fast axis to make the beam quality of both axes approximately equal. Furthermore, the beam transformation and compression can be carried out simultaneously, and the assembly error of this technique induced by the machining accuracy of prism's dimensions also can be greatly decreased. By this technique, a fiber-coupled system for one three-bar laser diode stack is designed and characterized. The experimental results demonstrate that the laser beams could be transformed into the required distribution with similar to 93.4% reshaped efficiency and coupled into a 400 mu m/0.22 NA fiber, which are consistent with the theory. (C) 2013 Society of Photo-Optical Instrumentation Engineers (SPIE)