Pump coupling optimization for high-power diode array pumped solid-state laser

Pump coupling is the hard-core of the high-power diode array pumped solid-state laser, which directly determines system cost, gain capacity, gain uniformity, pump-induced wave front distortion, pump-induced beam drift and so on. Based on the three-dimensional ray tracing method, this paper established the theoretical model of the high-power diode array end-pumped solid-state laser. Then a new type of pump coupling was optimized, which adopted a diode array arranged to be spherical and a hollow silver duct, and experiments on pump coupling efficiency and uniformity and transmission of the pump field were conducted. With the optimization, a uniform flat-topped pump-coupled output field was derived within 5 mm range from the duct exit, with 72% coupling efficiency and 80% transmission efficie