Scanning hard x-ray differential phase contrast imaging with a double wedge absorber.
Two-directional differential phase contrast images were measured using an x-ray microbeam and a double wedge absorber. The wedge absorber converts the displacement of an x-ray beam that is refracted by an object into change of x-ray intensity. The double wedge absorber made it possible to detect values of two-directional refraction angle with microrad sensitivity simultaneously. By Fourier integration of two-directional phase gradients calculated from the refraction angle instead of line integration of one-directional phase gradients, we obtained a quantitative phase map without artifacts even when only a part of the boundaries of the object were in the field of view. One of the characteristics of this technique is flexibility in a sensitivity of the phase gradient. By changing of shape or material of the wedge absorber, it is comparatively easy to control the detection limit of the refraction angle.
Mukaide
Taihei
T
Materials Technology Development Center, Canon Inc., 30-2, Shimomaruko 3-chome, Ohta-ku, Tokyo 146-8501, Japan.
Takada
Kazuhiro
K
Watanabe
Masatoshi
M
Noma
Takashi
T
Iida
Atsuo
A