In this work, fractional-derivative filtering is proposed to be incorporated in the system which detects projections emerging form an object as wave front phase variations only. Because it is well known that the square of the derivative of fractional order q equals ½ is linearly proportional to the first order derivative, a real spatial filter with amplitude transmittance proportional to the square root of the frequency has been prosed in order to obtain irradiance variations linearly related with the derivative of phase for phase object detection. Corresponding analysis is shown, where parallel phase projections are filtered with such a spatial filter prior to backprojection for reconstruction. Instead of performing integration of projections, description of the tomographic imaging process of the resulting space filtered backprojections is carried out and the 2D equivalence of the filter is discussed. Numerical examples are provided.

Date Published: 14 August 2001
PDF: 4 pages
Proc. SPIE 4419, 4th Iberoamerican Meeting on Optics and 7th Latin American Meeting on Optics, Lasers, and Their Applications, (14 August 2001); doi: 10.1117/12.437182

Published in SPIE Proceedings Vol. 4419:
4th Iberoamerican Meeting on Optics and 7th Latin American Meeting on Optics, Lasers, and Their Applications
Vera L. Brudny; Silvia A. Ledesma; Mario C. Marconi, Editor(s)