Development of hard deformable focusing mirror for general-purpose hard X-ray optics.

为了实现对尺寸小于几百纳米的硬X射线的衍射极限聚焦，研制了一种可弯曲成深度为几微米、精度优于几纳米的非球面形状的变形镜。采用斐索干涉仪作为反馈系统，保证了镜面形状的精度。在SPring-8的BL 29 XUL上测试了反射镜的硬X射线聚焦性能。证实了在衍射极限聚焦条件下，光束尺寸在微米到纳米尺度范围内是可控的。

In order to realize diffraction-limited focusing of hard X-rays with a size less than several hundreds of nanometers, a deformable mirror which can be bent into an aspherical shape with a depth of several micrometers and an accuracy better than a few nanometers was developed. The accuracy of the mirror surface shape was guaranteed and maintained by a feedback system with a Fizeau interferometer. Hard X-ray focusing performance of the mirror was tested at the BL29XUL of SPring-8. We confirmed that beam size was controllable in a range from micrometer to nanometer scale under diffraction-limited focusing condition.