Extreme ultraviolet transmission grating spectrometer

A transmission grating spectrometer has been developed for use in the extreme ultraviolet to soft x-ray region of the spectrum. The optical configuration of this spectrometer generates a focal curve which follows a cosine squared law and a spectral region may be forced to fall on the flattest part of that curve. This property allows the simultaneous observation of the entire region. A theoretical explanation of the shape and properties of this curve and experimental results from two spec trometers are presented. A holographic method of producing thin film transmission gratings for use in the extreme ultraviolet is provided as well as a brief history of the diffraction grating.