Patent ID: 6259763
Filing Date: 2001-07-10
Classification: G01N

Abstract:
An imaging spectrometer for spectral analysis of an extended hot plasma emitting X-rays, said spectrometer comprising:an X-ray detector;an elongated evacuated tube connected to an access window in a closed reactor vessel containing hot plasma for directing X-rays emitted by the hot plasma to a two dimensionally curved crystal; andthe two dimensionally curved crystal for reflecting X-rays emitted by the hot plasma onto said X-ray detector, wherein said crystal has a main radius of curvature R.sub.1 and said curvedcrystal and said X-ray detector are disposed on a common circle having a radius R.sub.2, where R.sub.1 and R.sub.2 are chosen so as to position focal lines for the meridional and sagittal rays according to localized measurements of the X-ray emissivity and the plasma parameters of the extended hot plasma and wherein the hot plasma, said X-ray detector and said curved crystal define a main diffraction plane, wherein said curved crystal reflects X-rays emitted by the hot plasma onto said X-ray detector at a Bragg angle of, or approximately equal to 45.degree., so that said curved crystal focuses X-rays which are near-parallel to said main diffraction plane to a central point on said X-ray detector and focuses near-parallel X-rays inclined to said main diffraction plane to different spaced points on said X-ray detector.