X-ray Microfocusing by Combination of Grazing-Incidence Spherical-Concave Mirrors

An optical system for X-ray microfocusing that consists of a pair of spherical mirrors has been developed. In grazing incidence optics with spherical (cylindrical) mirrors, focused beam size is generally restricted by spherical aberration. However, the spherical aberration can be corrected by the sequential reflection of two spherical mirrors, and submicrometer beam size can be obtained by total-reflection mirror optics with spherical concave mirrors. A sub-200 nm focusing has been achieved at an X-ray energy of 8 keV.