PROBLEM TO BE SOLVED: To prevent an artifact from being generated caused by fluctuation of a lattice position between prephotographing and aimed photographing.SOLUTION: A subject is arranged to carry out the aimed photographing under a state arranged with the subject, after prephotographed under a state arranged with no subject. The first phase differential images ψα1(x, y), ψβ1(x, y) are calculated when pre-photographed, using mathematical expressions (A), (B), based on a plurality of stripe images acquired by an X-ray image detector, and the second phase differential images ψα2(x, y), ψβ2(x, y) are calculated therein in the aimed photographing. Values of ψα2(x, y)-ψα1(x, y) and ψβ2(x, y)-ψβ1(x, y) are calculated in every pixel, and an already corrected phase differential image is generated by selecting the value with the smallest absolute value out of the both.COPYRIGHT: (C)2012,JPO&INPIT【課題】プレ撮影と本撮影との間での格子位置の変動によるアーチファクトの発生を防止する。【解決手段】被検体を配置しない状態でプレ撮影を行った後、被検体を配置して本撮影を行う。X線画像検出器で取得された複数の縞画像に基づき、数式(A)及び(B)を用いて、プレ撮影時に第1の位相微分像ψα1(x,y)及びψβ1(x,y)を算出し、本撮影時に第2の位相微分像ψα2(x,y)及びψβ2(x,y)を算出する。そして、画素ごとに、ψα2(x,y)-ψα1(x,y)とψβ2(x,y)-ψβ1(x,y)とを算出し、両者から絶対値の小さい方を選択することにより、補正済位相微分像を生成する。【選択図】図10
