Experimental analysis of the inserted waveguide CVD diamond window prototype for the ITER ECRH upper launcher

A new ITER torus window assembly with CVD diamond disk and corrugated waveguides is being investigated by using IR imaging and temperature measuring technique during high power RF microwave loading up to 0.5 MW at a frequency of 170 GHz at the JAEA Gyrotron facility. The inserted waveguide structure can minimize the penetration of high order modes into the window cuff or other parts of the window. The occurrence of higher order modes by mode conversion in the window assembly structure is monitored.