A diode-laser pump source with small focus diameter for end-pumped systems

A pump source with eight angular multiplexed laser diodes is built. The diode laser emission is collimated and focused using relatively inexpensive aspherical lenses. The maximum output power is 6.3W at 970nm. The overall transmittance of the beam shaping optics is T=85%. The electrical, temporal and spectral properties are studied. The variances of the spatial intensity distribution are Δr0x=99m and Δr0y=85m. The beam propagation factors are M2x=38 and M2y=112. The high intensity in the focus makes this system ideal for end pumping of solid state lasers.