m[Objectives]
To observe visible spectra with two-dimensional spatial resolution in the divertor region. The spectrometer has 92 view channels (vertically 60 channels, horizontally 32 channels) with a spatial resolution of ~1cm. It covers a spectral range of 350 - 800nm. From the measurement, it is possible to obtain spatial distribution of spectra intensities using a computer tomography technique.
[Diagnostic method]
Light collected by lenses is transmitted through optical fivers (~300m) from JT-60U to the spectrometer placed in the diagnostic room. The light is dispersed to the spectrometer with camera lenses to suppress chromatic aberrations and astigmatism, and detected with a back-illuminated CCD camera.
[Specifications]
| Spectrometer | |||
| Viewing chord : 100ch | Focal length : 0.2m (F/2) | ||
| Grating : 300g/mm | Wavelength band : 450nm | ||
| Time resolution : 200ms | |||
| CCD | |||
| Pixel format : 1340 x 1300 pixels | Size of pixel : 20 x 20 m |
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| Imaging area : 26.8 x 26 mm2 | Dynamic range : 16bits | ||
| ADC speed : 1MHz | CCD read noise : 18e- rms | ||
| Sensitivity : 93% at 550nm | |||
