Abstract

A number of applications, one of them being end-pumping of solid-state lasers, require tight focusing of several high power laser diode bars (LDBs) with maximum brightness and circular symmetry of radiation. Due to the high asymmetry factor of LDB output Q-w_xθ_x/w_yθ_x, where w and θ are half of the beam size and divergence angle along the corresponding axis respectively, the simple method to improve circular symmetry by beam packing along the fast y-axis¹ is not successful and thus a special technique of beam shaping is required. Earlier reported beam shaping technique used for a single LDB² is not effective in our case using several diode bars. In this paper we describe a novel technique of combining and beam shaping of a number of high-power LDBs so that an output beam with high brightness and improved circular symmetry is achieved (patent pending). Our approach is based on bulk-optics design offering in prospect cost effective industrial production and accepting LDBs with arbitrary emitter geometry.

© 1996 IEEE