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 dio de laser emission is collimated and focused using relatively inexpensive as pherical lenses. The maximum output power is 6.3W at 970 nm. The overall tr ansmittance of the beam shaping optics is T = 85%. The electrical, temporal and spectral properties are studied. The variances of the spatial intensit y distribution are Delta r(0x) = 99 mu m and Delta r(0y) = 85 mu m. The bea m propagation factors are M-x(2) = 38 and M-y(2) = 112. The high intensity in the focus makes this system ideal for end pumping of solid state lasers.