In this paper we present the current work and experience with using microfocus x-ray generator and commercial CCD camera for x-ray imaging purpose. There is a need in laboratories for the development of imaging methods approaching synchrotron radiation sources, where the brilliance of radiation is on very high-level. Generally, there is no continuous access to synchrotron facilities. Several synchrotron radiation laboratories allocate the access via a proposal system. Thus the time for synchrotron radiation experiments seldom exceeds more than 1-2 weeks per year, which restricts its application to a few selected experiments. Even in future, the routine characterization of samples will be performed mainly at the experimenters home laboratories [10]. In this contribution we show that with the present set-up it is possible to achieve the spatial resolution down to µ m and with the appropriate geometry a phase contrast images are observable.

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While channel-cut crystals, in which the diffracting surfaces in an asymmetric cut are kept parallel, can provide beam collimation and spectral beam shaping, they can in addition provide beam compression or expansion if the cut is V-shaped. The compression/expansion ratio depends in this case on the total asymmetry factor. If the Ge(220) diffraction planes and a total asymmetry factor in excess of 10 are used, the rocking curves of two diffractors will have a sufficient overlap only if the second diffractor is tuned slightly with respect to the first one. This study compares and analyses several ways of overcoming this mismatch, which is due to refraction, when the Cu K 1 beam is compressed 21-fold in a V21 monochromator. A more than sixfold intensity increase was obtained if the matching was improved either by a compositional variation or by a thermal deformation. This provided an intensity gain compared with the use of a simple slit in a symmetrical channel-cut monochromator. The first attempt to overcome the mismatch by introducing different types of X-ray prisms for the required beam deflection is described as well. The performance of the V-shaped monochromators is demonstrated in two applications. A narrow collimated monochromatic beam obtained in the beam compressing mode was used for high-resolution grazing-incidence small-angle X-ray scattering measurements of a silicon sample with corrupted surface. In addition, a two-dimensional Bragg magnifier, based on two crossed V15 channel monochromators in beam expansion mode and tuned by means of unequal asymmetries, was successfully applied to high-resolution imaging of test structures in combination with a Medipix detector.

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In standard single‐crystal V‐channel germanium (220) X‐ray beam‐expanding/compressing monochromators for Cu Kα1 radiation, a total beam expansion/compression of 5 and 10 corresponding to the asymmetry angles of 9 and 12° is achieved, respectively. Higher one‐dimensional beam expansion/compression is achievable using larger angles of asymmetry at the expense of a decrease in the total intensity. To increase the intensity, a linearly graded Ge‐rich GexSi1−x single crystal was used to prepare a monochromator with 15° asymmetry angles (total expansion/compression factor of 21) for Cu Kα1 radiation. The X‐ray diffraction measurements show more than three times higher peak intensity at the output compared with that of a pure Ge monochromator.