Development of figure correction system for inner surface of ellipsoidal mirrors

作者：Yokomae Shunya^*; Motoyama Hiroto; Mimura Hidekazu

来源：Precision Engineering-Journal of the International Societies for Precision Engineering and Nanotechnology, 2018, 53: 248-251.

DOI：10.1016/j.precisioneng.2018.04.010

• X-ray mirror
• Ion beam sputtering deposition
• Differential deposition
• Figure correction
• Numerically controlled processing

X-ray mirrors are widely used in advanced x-ray facilities. An ellipsoidal minor is used in soft x-ray focusing optics. To prevent a decrease in the intensity density or distortion of the wavefront of reflected x-ray beams, the inner surface of an ellipsoidal mirror should have high precision. Differential deposition is a method of fabricating a shape on a mirror surface. However, minors with a small diameter cannot be corrected by the conventional process.
In this study, a figure correction method employing ion beam sputtering deposition was developed. The sputtering target is placed inside the ellipsoidal mirror. Then, a cylindrical tube with a small aperture is inserted inside the mirror to realize selective deposition. The figure accuracy of an ellipsoidal mirror is improved even when its diameter is less than 10 mm. This figure correction system can also be applied to various axisymmetric devices with a small diameter.

• 出版日期2018-7