A new apparatus designed to measure the quality of X-ray and X-UV dispersive devices of synchrotron radiation in the range 5000-50 eV is described. It consists of a double mirror high-frequency rejector, a constant deviation double crystal monochromator and a spectrogoniometer θ-2θ. The monochromator and the spectrogoniometer can be equipped with natural and artificial crystals or with multilayer interferential mirrors (MIMs). Absolute measurements of transmission for thin screens can be made, as well as reflectance for mirrors or MIMs. So, it is possible to determine optical constants particularly in anomalous regions. In the same way XANES, EXAFS, ref EXAFS, surface roughness, .... measurements can be achieved. In this paper we present the first results obtained by using beryl crystals and MIMs near 1000 eV.
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