[OPTICAL REVIEW Vol. 17, No. 2 (2010) 79-83]
© 2010 The Japan Society of Applied Physics

Edge-Enhancement Fourier Transform X-ray Microscopy Using a Laguerre–Gaussian Zoneplate

Nándor BOKOR*, Andrew DOMONDON1,2, and Yoshinori IKETAKI3,4

Department of Physics, Budapest University of Technology and Economics, Budafoki u. 8, Budapest 1111, Hungary
1International Christian University, 3-10-2 Osawa, Mitaka, Tokyo 181-8285, Japan
2Committee on Conceptual and Historical Studies of Science, University of Chicago, 1126 East 59th St., Room 205, Chicago, IL 60637, U.S.A.
3PRESTO “Life Phenomena and Measurement Analysis” Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
4Olympus Corporation, 2-3 Kuboyama-cho, Hachioji, Tokyo 192-8512, Japan

(Received July 13, 2009; Accepted December 28, 2009)

Efficient techniques to achieve isotropic edge enhancement in optics involve applying a radial Hilbert, Laguerre–Gaussian, or differentiating filter on the object spectrum. We demonstrate a simple setup for isotropic edge-enhancement in soft-X-ray microscopy, using a single Laguerre–Gaussian zone plate (LGZP). Since the LGZP acts as a beam-splitter, diffraction efficiency problems usually associated with X-ray microscopy optics are not present in this system. As numerically demonstrated, the setup can detect optical path differences as small as λ/50 with high contrast.

Key words: X-ray, edge-enhancement, microscopy, phase-contrast, diffractive optical element, Laguerre–Gaussian, Hilbert, gradient

*Currently a JSPS fellow at Chemical Resources Laboratory, Tokyo Institute of Technology, Nagatsuta-cho, Midori-ku, Yokohama 226-8503, Japan. E-mail address: nandor.bokor@weizmann.ac.il