In the latest 20 years

X-ray imaging technology has developed rapidly in order to meet the needs of X-ray photo-etching

spatial exploration technology

high-energy physics

procedure diagnosis of ICF

etc. Since refractive indices of materials in the X-ray region are lower than 1

and X-ray is strongly absorbed by materials

the characteristics of X-ray increase greatly difficulty to obtain X-ray image. Conventional imaging methods are hardly suitable to X-ray range. In general

grazing reflective imaging and coding aperture imaging methods have been adopted more and more.We have designed a non-coaxial grazing reflective X-ray microscope which is composed of four spherical mirrors

in order to satisfy the requirement of the diagnosis of inertial confinement fusion (ICF). The four mirrors have the same radius of curvature. The radius of each mirror is 29 000 mm and the aperture is 30 mm×15 mm. Allowable tolerance of the radius is ≤0.2% and one of surface roughness (rms) is ≤0.6 nm. Evidently it is very difficult to fabricate and test such mirrors. In order to obtain eligible mirrors

we choose 18 mirror roughcasts and array them on a round disk according to format. The combined manufacturing method can ensure high accordant quality. The fabricated mirrors are tested by both templet and double round aperture methods. Radius errors of the mirrors is about 53 mm. The surface roughness (rms) of the mirrors is inspected by the relative interferometric equipment (WYKO) and atomic force microscope. Before and after coating the measured surface roughness is averagely 0.52 nm and 0.4 nm

respectively.