Scanning monochrometer crystal and method of formation

摘要

A doubly-curved crystal for use in a scanning monochromator is oriented with respect to a reference plane containing source and image locations of the monochromator. The crystal has concave planes of lattice points and a concave crystal surface which satisfy Johannson geometric conditions within the reference plane for a Rowland circle of radius R. The planes of lattice points are substantially spherically curved to a radius of 2R, and the crystal surface is substantially toroidally curved with a radius of substantially 2R within a plane perpendicular to the reference plane. The crystal may be formed by plastically deforming a cylindrically curved crystal blank over a doubly-curved convex die.