To suppress the laser-induced air breakdown which limited the transmission of 1064-nm Q-switched Nd:YAG laser pulses through hollow waveguide, a vacuum cell was attached to the waveguide ends, where the air was expelled from the cells as well as from the waveguide core region. With this scheme, the laser-induced air breakdown was completely suppressed, and in addition, the laser-induced damage threshold of the waveguide coating materials was significantly increased. With a 1-mm inner diameter, 1-m long, cyclic-olefin-polymer (COP)-coated silver hollow waveguide, a maximum transmitted laser energy reached approx. 200 mJ/pulse at 10 Hz in a straight waveguide condition. In a 90°-bent waveguide condition the laser-induced damage to the waveguide inner coating was observed, but a maximum transmitted energy in excess of 150 mJ/pulse at 10 Hz was obtained without any damage. With the transmitted laser pulses, sharp ablation in porcine myocardium tissues was demonstrated in vitro.
|ジャーナル||Proceedings of SPIE - The International Society for Optical Engineering|
|出版ステータス||Published - 2000 1月 1|
|イベント||Biomedical Diagnostic, Guidance, and Surgical-Assist Systems II - San Jose, CA, USA|
継続期間: 2000 1月 25 → 2000 1月 26
ASJC Scopus subject areas
- コンピュータ サイエンスの応用