Wide Field-of-view X-Ray Imaging Optical System Using Grazing-Incidence Mirrors

A field-curvature-corrected imaging optical system for x-ray microscopy using only grazing-incidence mirrors is proposed. It combines a Wolter type I (WO1) mirror pair, which forms a real image, with field curvature correction (FCC) optics—a convex hyperbolic mirror pair—that form a virtual image; compensation of the field curvatures realizes a wide field-of-view (FOV) and high magnification. Ray-tracing and wave-optics simulations verified the efficacy of the design, for which a FOV width was 111 µm—4.7 times larger than that for the uncorrected WO1 design. The addition of FCC optics also produced a 2.3-fold increase in magnification.