Author/Authors :
Huber، نويسنده , , A. and Brezinsek، نويسنده , , S. and Mertens، نويسنده , , Ph. and Schweer، نويسنده , , B. and Sergienko، نويسنده , , G. and Terra، نويسنده , , A. and Arnoux، نويسنده , , G. and Balshaw، نويسنده , , N. and Clever، نويسنده , , M. and Edlingdon، نويسنده , , T. and Egner، نويسنده , , S. and Farthing، نويسنده , , Catharina J. and Hartl، نويسنده , , M. and Horton، نويسنده , , L. and Kampf، نويسنده , , D. and Klammer، نويسنده , , J. and Lambertz، نويسنده , , H.T. and Matthews، نويسنده , , G.F. and Morlock، نويسنده , , C. and Murari، نويسنده , , A. and Reindl، نويسنده , , M. and Riccardo، نويسنده , , V. and Samm، نويسنده , , U. and Sanders، نويسنده , , S. and Stamp، نويسنده , , M. and Williams، نويسنده , , J. and Zastrow، نويسنده , , K.D. and Zauner، نويسنده , , C.، نويسنده ,
Abstract :
In preparation for ITER, JET has been upgraded with a new ITER-like wall (ILW) whereby the main plasma-facing components, previously made of carbon, have been replaced by Be in the main chamber and W in the divertor. A new endoscope with optimised divertor view has been developed in order to survey and monitor the emission of specific impurities such as tungsten, beryllium and the possibly remaining carbon in the tungsten divertor of the JET-ILW. It operates in the wavelength range from 390 nm to 2500 nm with high optical transmittance (≥30%) as well as high spatial resolution, that is ≤2 mm at the object plane and ≤3 mm over the whole depth of field (±0.7 m). The endoscope is a prototype for testing an ITER relevant design concept based on reflective optics only. The endoscope has an optimised observation in the near ultraviolet and in the blue spectral region to ensure the detection of the W I-emission line at 400.8 nm.
allel to the new optical design, a new type of ITER-like shutter system based on pneumatic techniques has been developed and integrated in the endoscope head. The new optical design includes options for an in situ calibration of the endoscope transmittance during the experimental campaign.
