J. Phys. IV France
Volume 104, March 2003
Page(s) 551 - 556

J. Phys. IV France
104 (2003) 551
DOI: 10.1051/jp4:20030142

Optical holography in the hard X-ray domain

N. Watanabe1, H. Yokosuka1, T. Ohigashi1, H. Takano2, A. Takeuchi2, Y. Suzuki2 and S. Aoki1

1  Institute of Applied Physics, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan
2  SPring-8, Mikazuki, Hyogo 679-5198, Japan

Present status of our developments of x-ray holographie microscopes at SPring-8 BL20XU is described. A combination of the x-ray undulator and a zone plate enabled us to make a coherent x-ray source of around 0.1  $\mu$m size. Using this secondary source, two types of x-ray holographie microscopes were investigated. First, a Gabor microscope in point-projection geometry was tested. A tantalum 0. 2 llm line-and-space pattern could be resolved. Second, using a zone plate as a beam splitter, a Fourier transform holographie microscope was tested. A tantalum 0.2  $\mu$m line-and-space pattern could be observed. Polystyrene beads of 2.8  $\mu$m and 0.8  $\mu$m in diameter could be observed. In Fourier transform holography, a reconstructed image of a specimen that is located out of the plane of the reference source is blurred. Numerical focusing of such an x-ray hologram could be successfully demonstrated.

© EDP Sciences 2003