II Workshop s-Braxin on New technologies in X-Ray Imaging

 Dr. Jürgen Mohr

Contact: juergen.mohr@kit.edu

Research Topics: Lithography, X-ray Optics, Grating based Interferometry

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Jürgen Mohr, graduated in physics in 1983 and received his Ph.D. in mechanical engineering in 1987 both from the University of Karlsruhe. Since 1987 he is with Karlsruhe Institute of Technology. Since 1992 he is leading the X-ray lithography and micro-optics department. Since 2010 he is spokesperson of the Helmholtz Research Infrastructure KNMF (Karlsruhe Nano and Micro Facility), an open access user facility in the field of multi material nano and microfabrication and characterization. Since 2011 he is also head of the virtual institute for New X-ray Imaging Methods for Materials Analysis.

As one of the first researchers active in the LIGA process, J. Mohr has pioneered the work on deep X-ray lithography and it’s use in fabrication of high aspect ratio micro optical and micro mechanical components. Today his research focus is on the fabrication of X-ray optical components for imaging application like X-ray microscopy and X-ray interferometry with synchrotron as well as with lab sources.

J. Mohr is a world-wide recognized expert in micro fabrication and micro optics. He is co-author of one textbook on micro technology and has more than 100 Web of Science indexed publication in international journals. He is member of the IEEE-LEOS society and speaker of KIT in Photonics BW; he is heading the working group on micro optics of VDI/VDE Germany.

Contribution: Fundamentals of X-ray imaging

The microstructure of a material is a crucial characteristic as it determines the macroscopic behavior of the material such as its mechanical properties. Thus, the need for experimental methods that provide access to this microstructure consistently increases with the development of new materials as well as the advancement of already established materials. Among a few other techniques, today X-ray radiography and computed tomography (CT) are the two most common techniques applied in order to obtain information on the internal structure of a material in two or three dimensions respectively. They are valuable inspection tools for numerous manufactured items and they provide quality assurance without sacrificing material or destroying samples. Today, e.g. welds and metallic castings are inspected frequently, because it helps to reveal defects in the material below the surface. With the increased use of new light weight fabrication materials X-ray inspection has grown as a reliable examination method for numerous types of plastic, silicone, microchips etc., fiber reinforced materials, are one class of materials where CT is extensively applied in order to analyze orientation and length distribution. In the talk we will present the principle of X-ray imaging methods and give a few examples to demonstrate the value of these none destructive methods in materials characterization.

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