Characterizing the modulation transfer function for X-ray radiography in high energy density experiments

DOI PDF Web Site 1 Citations
  • E. Gumbrell
    A.W.E. 1 , Aldermaston, Reading RG7 4PR, United Kingdom
  • J. M. McNaney
    Lawrence Livermore National Laboratory 2 , 7000 East Ave., Livermore, California 94550, USA
  • C. M. Huntington
    Lawrence Livermore National Laboratory 2 , 7000 East Ave., Livermore, California 94550, USA
  • A. G. Krygier
    Lawrence Livermore National Laboratory 2 , 7000 East Ave., Livermore, California 94550, USA
  • H.-S. Park
    Lawrence Livermore National Laboratory 2 , 7000 East Ave., Livermore, California 94550, USA

Abstract

<jats:p>The Modulation Transfer Function (MTF) is an established means for characterizing imaging performance of X-ray radiography systems. We report on experiments using high energy, laser-driven X-ray radiography systems that assess performance using MTF values measured with the knife-edge projection method. The broadband, hard X-ray systems under study use line-projection imaging produced by narrowing the laser-generated X-ray source with a slit. We find that good contrast resolution can be achieved (the MTF = 0.5 at 75 μm wavelength) and that this performance is reproduced on different laser facilities. We also find that the MTF is sensitive both to the thickness of the line-projection slit and to the backing material thickness under the knife-edge. Both these sensitivities are due to a common mechanism, namely induced changes in the spectrally-averaged spatial widths of the X-ray source. The same line-projection system is also used on experimental campaigns measuring Rayleigh-Taylor instability growth by dynamically imaging sinusoidal, high Z micro-targets with wavelengths of 100 μm or less. By applying the measured MTF values to correct the ripple target contrast measurements, we can predict ripple growth to approximately 10% accuracy.</jats:p>

Journal

Citations (1)*help

See more

Report a problem

Back to top