SEDL / STP / STP1015-EB / STP18752S

Laser Induced Mo Mirror Damage for High Power CO² Laser

Okamoto, H
Central Research Labolatory, Nippon Mining Co., Ltd., Toda-shi, Saitama,

Matsusue, N
Central Research Labolatory, Nippon Mining Co., Ltd., Toda-shi, Saitama,

Kitazima, K
Central Research Labolatory, Nippon Mining Co., Ltd., Toda-shi, Saitama,

Yoshida, K
Central Research Labolatory, Nippon Mining Co., Ltd., Toda-shi, Saitama,

Ichikawa, Y
Central Research Labolatory, Nippon Mining Co., Ltd., Toda-shi, Saitama,

Yamanaka, M
Central Research Labolatory, Nippon Mining Co., Ltd., Toda-shi, Saitama,

Yamanaka, T
Central Research Labolatory, Nippon Mining Co., Ltd., Toda-shi, Saitama,

Tsunawaki, Y
Central Research Labolatory, Nippon Mining Co., Ltd., Toda-shi, Saitama,

Pages: 13    Published: Jan 1988

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Source: STP1015-EB

Abstract

We have developed a high-purity molybdenum (Mo) mirror by electron-beam melting method (e.b.m. Mo mirror). Its high laser-damage threshold has been demonstrated for the high-power TEA CO² laser system. The e.b.m. Mo mirror has a damage threshold of 2 to 4 times higher than that of an Au coated glass mirror and had a life time of 3 times longer than that of a powder metallurgy Mo mirror (p.m.Mo mirror) when the laser energy density of higher than 60 J/cm² was irradiated. We found that on the laser-damage threshold the difference between the e.b.m. Mo mirror and the p.m.Mo mirror was due to the fine surface without voids and the small amount of impurities.

Keywords:
Laser mirror, molybdenum, CO, 2, laser, laser damage, polished surfaces, surface roughness, optical characterization

Paper ID: STP18752S
Committee/Subcommittee: F01.02
DOI: 10.1520/STP18752S
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