Diode laser bar beam shaping technique

Abstract

Due to their relative cheapness and wide commercial availability high-power di ode bars are becoming increasingly at tractive as pump sources for high-power solid-state lasers. Unfortunately, because of the highly elliptical output beam (~1 μm × 10 mm) and highly nondiffraction-limited nature of these devices, they cannot readily be focused into small, circular spots, which are suitable for efficient end-pumping of solid-state lasers. To date, many of the end-pumping schemes, which have been employed with diode bars, have either produced a rather large focused pump beam diameter (typically ~ 1mm),1,2 or have employed relatively complex resonator designs (e.g., the tightly-folded resonator).3