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Journal of the Optical Society of America A

Journal of the Optical Society of America A


  • Editor: Franco Gori
  • Vol. 28, Iss. 12 — Dec. 1, 2011
  • pp: 2501–2509

Characterizing flash-radiography source spots

Carl Ekdahl  »View Author Affiliations

JOSA A, Vol. 28, Issue 12, pp. 2501-2509 (2011)

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Flash radiography of large hydrodynamic experiments driven by high explosives is a venerable diagnostic technique in use at many laboratories. The size of the radiographic source spot is often quoted as an indication of the resolving power of a particular flash-radiography machine. A variety of techniques for measuring spot size have evolved at the different laboratories, as well as different definitions of spot size. Some definitions are highly dependent on the source spot intensity distributions, and not necessarily well correlated with resolution. The concept of limiting resolution based on bar target measurements is introduced, and shown to be equivalent to the spatial wavenumber at a modulation transfer function value of 5%. This resolution is shown to be better correlated with the full width at half-maximum of the spot intensity distribution than it is with other definitions of spot size.

© 2011 Optical Society of America

OCIS Codes
(110.3000) Imaging systems : Image quality assessment
(110.4100) Imaging systems : Modulation transfer function
(340.7440) X-ray optics : X-ray imaging
(350.6980) Other areas of optics : Transforms

ToC Category:
X-ray Optics

Original Manuscript: August 2, 2011
Manuscript Accepted: August 24, 2011
Published: November 11, 2011

Carl Ekdahl, "Characterizing flash-radiography source spots," J. Opt. Soc. Am. A 28, 2501-2509 (2011)

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