DiffractionĪnother major application of refractive lenses from RXOPTICS is x-ray diffraction. Note that for CRLs containing such a large number of lenses it is important to take into account thick lens effects in particular, sample and image distance have to be understood with respect to the primary and the secondary principal plane, respectively. Ni mesh (left, from Lengeler et al.) and Ta Siemens star (right, by DiMichiel et al.) The condenser CRL, consisting of 125 Al 2D lenses with R = 0.2 mm, was placed 2.4 m from the sample and, thus, produced a virtual focal spot inside the objective lens (Figure 1). The distance of the objective CRL from the sample was L 1 = 906 mm, resulting in an image distance of L 2 = 11,778 mm. This CRL was made up of 60 lenses with R = 0.05 mm and 321 lenses with R = 0.2 mm. It is obvious that the image is practically free of aberrations.įigure 2 (right) shows a Ta Siemens star that is imaged at 46 keV by Al 2D lenses with a magnification factor L 2 / L 1 of 13 (private communication with M. The distance of the objective CRL from the sample was L 1 = 546 mm, yielding an image distance of L 2 = 5460 mm. A large magnification relieves the requirements on the resolution of the x-ray detector.įigure 2 (left) shows a Nickel mesh with a period of 12.7 μm that was imaged at 12 keV by 91 beryllium 2D lenses with R = 0.2 mm and a magnification factor L 2 / L 1 = 10 onto a high resolution film (from Lengeler et al. The image is formed by an objective lens with a small focal length which allows a large magnification L 2 / L 1. Usually, illumination of the object from behind is achieved by a prefocusing lens (condenser) in order to adjust the beam size to the sample (Figure 1, cf. A common application for refractive lenses from RXOPTICS is x-ray imaging in transmission mode.
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