Abstract
We have independently developed the laser decontamination device consisting of a diffraction-limited single-mode CW fiber laser and a high-speed galvanometer. The surface of RI (radioactive isotope) contaminants in the nuclear reactor stainless steel, concrete, glass, and inorganic and organic materials was sublimated and instantly evaporated with the high-power density and high-speed scanning laser light, and to decontaminate below the detection limit. Recently, we have successfully been able to observe the sublimation and evaporation of this laser decontamination device with highspeed movie camera. By observing low-speed movie images below the detection limit and high-speed movie images, it can be seen that the high-power density and high-speed scanning is needed to realize the sublimation and evaporation without residual contamination. It can be seen that the high-power density and low speed scanning is conversely resulted the expanded melting in which the contamination remains. In the conference, the device design that realizes the decontamination below the detection limit will be reported. And also, the decontamination process using the sublimation and evaporation by observing high-speed movie will be discussed.
