Diffraction Filters in XUV Spectroscopy.

The transmission of diffraction filters depends mainly on the geometrical parameters, the slit width 2d, the distance x(n,n-1) of the slits from each other, and the number n of the slits. Therefore the filter curve may be "shifted" continuously throughout the XUV spectral region simply by changing the corresponding parameters. This is discussed in detail. Diffraction filters can be utilized in a wide range of experiments in solar, stellar, and laboratory spectroscopy. As is shown for three well known optical arrangements, diffraction filters improve the signal-to-noise ratio considerably, to some extent simplifying the experiment at the same time. Consequently this new technique is an efficient optical tool.