Abstract
Photoluminescence spectroscopy of the plasma induced by the continuous CO2 laser was observed in the range of wavelength 190-400 nm. From the results of the spectrum analyses of the plasma, the plasma temperature was measured and its formation mechanism was discussed.
It was found that the plasma consisted of rich emission lines of excited and ionized metallic elements. The intensity of atomic emission lines from the plasma was dependent upon the physical properties of the gas element such as ionization potential and heat conductivity. The plasma temperature estimated by a line intensity ratio method was 13000-14000 K irrespectively of the kind of shielding gas element. Critical power density of CO2 laser for maitaining the plasma was about 5×105 W/cm2.