Compact 170-W continuous-wave diode-pumped Nd:YAG rod laser with a cusp-shaped reflector.

Flash-lamp style optical pump cavity techniques for side pumping small-diameter laser rods with large-area stacked diode-laser arrays are applied. With a cusp-shaped reflector as a nonimaging concentrator, the light is coupled from the 4.5 cm × 1 cm emitting surface of a microchannel-cooled 660-W cw stacked array to a 4-mm-diameter Nd:YAG rod. With a rod length of 70 mm, 170-W cw output power is reached with an optical efficiency of 26%. The design is insensitive to mechanical distortions and allows for a compact, rugged, close-coupled arrangement without the need for further coupling optics.