Development of thermal image plate using ceramic luminescence materials for aligning and stabilizing beam axis of CO2 laser

A thermal image plate (TIP) using ceramic luminescence materials has been developed in order to visualize a beam spot of a CO2 laser which is used as a light source of an interferometer developed in JT-60SA. By using CaAlSiN3:Eu2+ (CASN), the TIP was developed, and its property was assessed. A CASN TIP was able to visualize the invisible CO2 laser beam as a negative image. The beam diameter and the stability of the beam axis measurement obtained with the CASN TIP were approximately the same as that obtained with a commercial TIP. Furthermore, the time response of the CASN TIP at the best was approximately the same as that of the commercial TIP. The CASN TIP which had the highest time response was applied to the beam axis stabilizer, and then the beam axis stabilization was successfully performed in 2 h. Published by AIP Publishing.