Abstract

Ultraviolet (UV) lasers are establishing new applications such as precise hole drilling, optical lithography, or mask repairing. Excimer lasers of 10-100 W class are under development for these UV-source applications. However, the disadvantage of excimer lasers is that they use special high-pressure gases, hence the system and maintenance cost could be higher compared with other industrial lasers. Solid-state lasers with fourth generation are also promising UV sources, however, the UV powers are still around 1-W level. Moreover, because the W-class UV powers of solid-state lasers have been proved in most cases by using low-power TEM₀₀ mode beams, it is difficult to foresee that higher UV-power generation would be proved in the near future. In this paper, we report our attempt to generate high-power UV laser beams with practically acceptable conversion efficiency by using our high-brightness industrial Nd:YAG laser.

© 1996 Optical Society of America