Design and optimization of high resolution X-UV monochromators for synchrotron radiation

The synchrotron radiation became in 25 years an essential tool of the fundamental research. This radiation source is polychromatic. Its correct use leads to a transfer optical system, the light line, where the monochromator is very important. The monochromators performances are characterized by the resolution and the flux offered to the sample. To obtain a high resolution it is necessary to define an optical combination with poor geometrical aberrations. In the first part of the work, the author shows how the holographic network monochromators (at super ACO), initially designed for high resolutions, have been disturbed by fabrication accuracy and stability problems. In the second part a computer code allowing the optimization of most of the monochromators has been developed. This code also allows to forecast the real performances taking into account the fabrication accuracy and margins. (A.L.B.)