The development and performance of a high-precision polarimeter for the polarization analysis in the soft x-ray region is presented. This versatile, high-vacuum compatible instrument is supported on a hexapod to simplify the alignment with a resolution less than 5 μrad, and can be moved with its own independent control system easily between different beamlines and synchrotron facilities. The polarimeter can also be used for the characterization of reflection and transmission properties of optical elements. A W/B(4)C multilayer phase retarder was used to characterize the polarization state up to 1200 eV. A fast and accurate alignment procedure was developed, and complete polarization analysis of the APPLE II undulator at 712 eV has been performed.

The application of a two dimensional (2D) grating interferometer-Fresnel zone plate combination for quantitative submicron phase contrast imaging is reported. The combination of the two optical elements allows quick recovery of the phase shift introduced by a sample in a hard X-ray beam, avoiding artifacts observed when using the one dimensional (1D) interferometer for a sample with features oriented in the unsensitive direction of the interferometer. The setup provides submicron resolution due to the optics magnification ratio and a fine sensitivity in both transverse orientations due to the 2D analysis gratings. The method opens up possibilities for sub-micro phase contrast tomography of microscopic objects made of light and/or homogeneous materials with randomly oriented features.

Engineered porous materials are proposed as random absorption masks for X-ray phase-contrast imaging in high-energy regions (i.e. over 50 keV).

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This paper describes two fabrication techniquesdry and wet etching-for microstructured optical arrays (MOAs). The MOAs consist of arrays of channels deep etched in silicon. They use grazing incidence reflection to focus the X-rays through the consecutive aligned arrays of channels, ideally reflecting once off a vertical and smooth channel wall in each array. The MOAs were proposed by the Smart X-ray Optics (SXO) programme as small scale optics for micro-probing of biological cells and tissues. The first fabrication method requires inductively coupled plasma (ICP) using Bosch processes. The second one involves etching <110> silicon wafers in alkaline solutions.