Digital Holography for erosion monitoring inside the ITER Tokamak

摘要

In the International Thermonuclear Experimental Reactor (ITER) Project, under construction in southern France, there will be a need for continually measuring the erosion at the wall, after the machine starts operating. A multiple wavelength interferometric technique based on digital holography is proposed for the erosion measurement. This technique has the ability to tackle the challenging environmental conditions within the reactor by a long distance measurement, where a relay optic will be used for imaging the investigated surface on the detector. We will show that shape measurements of objects located at a distance of more than 13 m from the measuring head can be carried out by the multiple wavelength interferometric technique. A depth accuracy of ±10 μm is achieved.