2019 Volume 14 Pages 1405042
The visible spectroscopy reference system (VSRS) diagnostic will be used to measure the continuum visible light emitted from the plasma in ITER. Because the field of view of the VSRS system is aligned to a hole on a blanket module with a retroreflector on the bottom, which will be shared with an interferometer measurement, it has a potential to be free from the stray light, which may disturb signals for optical diagnostics in ITER. In this study, performance of the stray light reduction in the VSRS is investigated using a ray tracing simulation. We investigated the influences of the reflection property of the retroreflector and first mirror for the signal and stray light intensity.