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Concentrator of laser energy for thin vapour cloud production near a surface

P. I. Melnikov·B. A. Knyazev·J. B. Greenly
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Abstract

A novel scheme is presented for production of a thin ($<1$ mm) uniform vapor layer over a large surface area ($>100$ cm$^2$) by pulsed laser ablation of a solid surface. Instead of dispersing the laser energy uniformly over the surface, a modified Fabry-Perot interferometer is employed to concentrate the laser energy in very narrow closely-spaced concentric rings. This approach may be optimized to minimum total laser energy for the desired vapor density. Furthermore, since the vapor is produced from a small fraction of the total surface area, the local ablation depth is large, which minimized the fraction of surface contamination in the vapor. Key words: laser evaporation, thin gas layer formation.

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P. I. Melnikov, B. A. Knyazev, J. B. Greenly. 1998-08-06. Concentrator of laser energy for thin vapour cloud production near a surface. https://doi.org/10.1016/s0168-9002(98)00453-7

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