Design and Performance of Holographic Concave Gratings

Following a brief introductory remark on the holographic grating, the possibility of designing concave gratings for a specific application is discussed, giving basic ideas of the grating design, actual design procedures, and feasible ways of improving the existing design methods. As a proof of the usefulness of the design method developed by the authors, spot diagrams and experimental results are given for aberration-reduced holographic concave gratings that have been designed and produced specifically for a Seya-Namioka monochromator. The efficiency, stray light, and polarization characteristics of holographic and conventional concave gratings are compared for the purpose of giving some idea about the relative merits of the two kinds of gratings. The design method is also applied to the determination of the ruling parameters needed for the production of mechanically ruled stigmatic concave gratings.