[OPTICAL REVIEW Vol. 7, No. 6 (2000) 566-572]

A New Method of Analyzing Edge Effect in Phase Contrast Imaging with Incoherent X-rays

Akira ISHISAKA, Hiromu OHARA and Chika HONDA

Medical and Graphic Imaging R&D Center, Konica Corporation, No. 1 Sakura-machi, Hino, Tokyo, 191-8511 Japan

(Received March 24, 2000; Accepted July 4, 2000)

A method has been devised to calculate the half-width of the phase contrast enhanced edge of an X-ray image with incoherent X-rays. This method is based on changes in the wave fronts of X-rays after penetrating an object, and it takes into account the blur due to penumbra observed in practical radiographic imaging. The method closely predicted edge enhancement when images of a plastic fiber were produced with practical X-ray tubes (Cu, Mo, and W anodes with focus-diameters of 10, 100, and 40 μm, respectively). Thus, the method shows promise in facilitating phase contrast X-ray imaging in both medical radiography and non-destructive inspection using incoherent X-rays from X-ray tubes with substantial focus-sizes.

Key words : phase contrast, incoherent X-ray, edge effect, half-width of edge enhancement, Cu, Mo, and W anodes X-ray tubes, refraction