Experience with Imaging by Using of Microfocus X-Ray Source

Abstract

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.

Phase contrast imaging of lightweight objects using microfocus X-ray source and high resolution CCD camera

“…It has a very regular internal structure as shown in figure 7. Results of measurements of the spatial resolution presented in [5] are confirmed by this CT experiment. We can recognize a wall thickness of the wood cells about 3 µm (see figure 7a).…”

“…An important prerequisite for high resolution CT is high spatial resolution of the 2D projections which is possible by using an optical magnification of the object. With the present set-up it is possible to achieve the spatial resolution of the whole X-ray imaging system down to 3 µm [5]. There is a possibility to express the so-called CT voxel size as the ratio of CCD pixel size and magnification factor of the imaging setup.…”

“…By positioning the imaging plane behind the object and changing distance Z we go through individual areas with different Fresnel numbers as shown in figure 1. Figure 2 shows radiographic projections obtained in three different regions in imaging space [5]. With the increase of the distance Z the visibility of fine structures increases.…”

Calculations and surface quality measurements of high-asymmetry angle x-ray crystal monochromators for advanced x-ray imaging and metrological applications

“…1 This was the motivation for the x-ray microscopy setup we developed, which is based on an x-ray microfocus generator attaining a spatial resolution down to 3 μm with an average lateral coherence length of 0.3 to 13 μm and up to a 140-fold geometrical magnification. 2,3 However, such a setup uses broad polychromatic radiation, therefore, the extracted quantities from the x-ray images, such as attenuation coefficient and the retrieved phase, are affected by beam hardening effects and the x-ray images have usually a reduced contrast due to the presence of scattering. The use of monochromatic radiation will, therefore, be of benefit but at the cost of a significant photon flux loss.…”