A 193 nm light source using fiber amplifier and nonlinear wavelength conversion

One approach to compact UV light sources is an all-solid-state 193 nm laser system, which utilizes an Er-doped fiber amplifier (EDFA) of 1547 nm wavelength as part of the fundamental light source, and five-stage frequency conversion optics for generating the eighth harmonic of 193 nm light. We propose the use of Gd/sub x/Y/sub 1-x/Ca/sub 4/O(BO/sub 3/)/sub 3/ as the fourth-harmonic crystal to improve the wavelength conversion optics, and report the results of durability tests up to 500 hours.