Abstract

Recent advances in x-ray sources, optics, and detectors have opened the door to three-dimensional holographic microscopy. Soft x-ray holography is a promising tool for study of micrometer-sized biological objects in their natural state. X-ray holograms obtained to date resolve features smaller than 100 nm; however, they yield little depth information because of their relatively low numerical aperture. The effective aperture and depth resolution can be improved by combining holograms recorded at various illumination angles. We have undertaken an experimental demonstration of this technique at the NSLS undulator beamline X1A. By using coherent 3.2-nm x-radiation, Fourier transform holograms of microfabri-cated test objects were recorded at several orientations with a CCD camera. The holograms were numerically assembled and reconstructed. Preliminary results are presented.

© 1992 Optical Society of America