Transversally diode-pumped Q-switched Nd:YAG laser with improved power and spatial characteristics

The power and output beam spatial properties of the transversally diode-pumped Q-switched Nd:YAG laser with the active element surrounded by the low-absorption light-scattering layer have been investigated. The layer consisted of the bonding agent in which the solid particles, like aluminum oxide or magnesium oxide, effectively scattering the light was uniformly distributed. The particle diameter was mainly in the range of 2–5μm. It has been shown that application of such layer to the diode-pumped Q-switched Nd:YAG laser head allows suppressing the amplified spontaneous emission and/or internally circulating parasitic lasing modes. At the optimized concentration of the light-scattering solid particles the output lasing pulses with the energy of 188–210 mJ (the wavelength of 1064 nm, the pulse repetition rate of 30 Hz) and improved spatial characteristics were obtained using the pump unit based on three laser diode matrixes.