![]() ![]() The resulting image resolution mainly depends on the diameter D Source of the X-ray source, as the half shades caused by a larger source lead to blurred images. ![]() The magnification of the set-up is the quotient L 2 / L 1 with the distance source-sample L 1 and the distance source-image L 2. Influencing the direction of the X-rays is not needed in the basic version of this type of microscope. Table 1: Comparing different types of microscopes (values only for orientation)įull field X-ray microscopes can be either enlarging shadow projection microscopes (figure 1) or microscopes with focusing optical elements (figure 2).Ĭonsist of a point-shaped X-ray source, optional of an optics 4 producing a demagnified image 5 of the source 1, the sample 2 positioned close to the source 1 (respectively to the image 5 of the source) and a detector for the resulting X-ray image 3 (fig. In table 1 some characteristics of different microscopes are compared. Scanning electron microscopes in comparison have a high image resolution, but they need vacuum-proof samples with metallic or metallized surfaces and they can not image the inner of a sample. The wavelength of X-rays is much shorter than the wavelength of visible light, so the limit of the optical resolution (caused by diffraction) of X-ray microscopes is far below the diffraction limit of microscopes working with visible light. X-ray microscopes can achieve higher optical resolution than microscopes using visible light. So X-ray microscopes can image the inside of samples opaque for visible light. X-rays penetrate matter far easier than visible light. What are the advantages of X-ray microscopes over other types of microscopes? The detector then measures the total intensity over time coming from the currently illuminated spot on the sample and the image is calculated from this data when the scanning process is finished. In scanning microscopes the sample is illuminated with a bright well focused spot scanning over the sample. In full field microscopes the whole field of view is imaged to a detector plane at the same time. ![]() There are two main principles of microscopes to be distinguished: full field microscopes and scanning microscopes. An X-ray microscope is an instrument used to produce enlarged images of samples illuminated with X-rays. ![]()
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