Excimer laser interactions Available to Purchase

Excimer (rare-gas, halide) lasers are finding increasing use in industry, and occupational exposure to ultraviolet laser radiation from these lasers is now commonplace. MPE limits have had to be extended to 180μm because of the 193-μm line of the ArF laser. The potential hazards associated with exposure to very-short wavelength 193-μm laser line was recently examined by studying the threshold for photokeratitis at 193-μm. This threshold was obtained for the rabbit cornea using an ArF excimer laser. Because ablation occurs at a level below that for photokeratitis, it was necessary to expose the cornea to a lengthy series of low-energy exposures. It is concluded that the 193μm photons have such a shallow penetration depth, being limited to the outermost epithelial cells, that classical photokeratitis occurs from the fluorescence emitted at the corneal epithelial absorption site. An intact tear film may help to protect the cornea from low-level, scattered 193μm laser radiation.