Related Experiment Video
Updated: Jan 28, 2026

Elemental-sensitive Detection of the Chemistry in Batteries through Soft X-ray Absorption Spectroscopy and Resonant Inelastic X-ray Scattering
Published on: April 17, 2018
Development of electroforming process for soft x-ray ellipsoidal mirror.
Takehiro Kume1, Yoshinori Takei1, Satoru Egawa1
1Department of Precision Engineering, Graduate School of Engineering, The University of Tokyo, 7-3-1 Bunkyo-ku, Hongo, Tokyo 113-0033, Japan.
Researchers developed a new nickel electroforming method to create precise soft x-ray ellipsoidal mirrors. This technique achieves nanometer-level accuracy, enabling highly focused soft x-ray beams for advanced applications.
Area of Science:
- Optics and Photonics
- Materials Science
- X-ray Optics
Background:
- Soft x-ray focusing requires mirrors with nanometer-level surface accuracy.
- Direct fabrication of small-diameter, high-accuracy ellipsoidal mirrors is challenging.
Purpose of the Study:
- To develop and evaluate a novel fabrication process for soft x-ray ellipsoidal mirrors.
- To assess the shape accuracy of mirrors produced via nickel sulfamate electroforming.
Main Methods:
- Replication of a high-precision quartz mandrel using nickel sulfamate electroforming.
- Fabrication of a 40-mm length ellipsoidal mirror.
- Shape accuracy evaluation using a contact probe measurement method.
Main Results:
- The fabricated ellipsoidal mirror achieved a replication error RMS of 27.2 nm over the entire surface.
- Near the mirror's center, the RMS replication error was reduced to 14.7 nm.
- Wave-optical simulations indicate potential for focusing soft x-rays to a 400 nm spot.
Conclusions:
- Nickel sulfamate electroforming is a viable method for fabricating high-accuracy soft x-ray ellipsoidal mirrors.
- The developed process meets the stringent shape requirements for advanced soft x-ray applications.
- The fabricated mirrors show promise for achieving sub-micron focusing of soft x-rays.
Related Concept Videos
Geoid and Ellipsoid
X-ray Crystallography
Diffraction
Diffraction is the change in the direction of travel experienced by an electromagnetic wave when it encounters a physical barrier whose dimensions are comparable to those of the wavelength of the light. X-rays are electromagnetic radiation with wavelengths about as long as the distance between neighboring...
X-ray Imaging
X-ray Diffraction of Biological Samples
According to Bragg's law, when X-rays strike the sample positioned on a stage, the rays are scattered by the electron clouds around the sample atoms. The X-ray diffraction or scattering is caused by constructive interference of the X-ray waves that reflect off the internal...
Radiological Investigation I: X-ray and CT
Imaging Studies for Cardiovascular System III: X-Ray
Definition and Purpose
An X-ray, or radiograph, is a non-invasive method that uses ionizing radiation to take images of internal structures. It is mainly used in cardiac imaging to examine the heart, lungs, and major blood vessels, aiming to identify abnormalities in the heart's size, shape, and position, such as heart failure, congenital defects, and vascular...

