%0 Journal Article
%T Low-Cost Real-Time Gas Monitoring Using a Laser Plasma Induced by a Third Harmonic Q-Switched Nd-YAG Laser
%A Syahrun Nur Abdulmadjid
%A Koo Hendrik Kurniawan
%A Tjung Jie Lie
%A Yong Inn Lee
%J ITB Journal of Engineering Science
%D 2005
%I Institut Teknologi Bandung
%X A gas plasma induced by a third harmonic Nd-YAG laser with relatively low pulsed energy (about 10 mJ) has favorable characteristics for gas analysis due to its low background characteristics, nevertheless a high power fundamental Nd-YAG laser (100-200 mJ) is widely used for laser gas breakdown spectroscopy. The air plasma can be used as a low-cost real-time gas monitoring system such that it can be used to detect the local absolute humidity, while a helium plasma can be used for gas analysis with a high level of sensitivity. A new technique using a helium plasma to improve laser ablation emission spectroscopy is proposed. Namely, the third harmonic Nd-YAG laser is focused at a point located some distance from the target in the 1-atm helium surrounding gas. By using this method, the ablated vapor from the target is excited through helium atoms in a metastable state in the helium plasma.
%K third harmonic Nd-YAG laser
%K air plasma
%K He plasma
%K He metastable state
%K gas monitoring
%K gas analysis
%U http://journal.itb.ac.id/download.php?file=B05004.pdf&id=99&up=3