PROBLEM TO BE SOLVED: To correct an artifact caused by a gap of scanning positions between a pre-photographing and a main photographing.SOLUTION: A radiographic system is constituted in the following. An image processing part 14 includes: a calculating part 56 for the amount of the gap of the scanning position a scanning position correcting part 57 and a subtraction processing part 52. The calculating part 56 for the amount of the gap of the scanning position calculates the amounts of the gaps of respective scanning positions between the pre-photographing and the main photographing by detecting the difference of intensity modulation signals between the pre-photographing and the main photographing. The scanning position correcting part 57 corrects respective scanning positions to be used when a phase differential image is formed by a phase differential image forming part 50 during the main photographing, by using the amounts of the gaps calculated by the calculating part 56 for the amount of the gap of the scanning position. The subtraction processing part 52 subtracts the second phase differential image formed when the pre-photographing is performed from the first phase differential image formed when the main photographing is performed.COPYRIGHT: (C)2012,JPO&INPIT【課題】プレ撮影と本撮影との間での走査位置のずれに起因するアーチファクトを補正する。【解決手段】画像処理部14に、走査位置ズレ量算出56、走査位置補正部57、及び減算処理部52を設ける。走査位置ズレ量算出56は、プレ撮影と本撮影との間で、強度変調信号の差異を検出することにより、プレ撮影と本撮影との間での前記各走査位置のズレ量を算出する。走査位置補正部57は、本撮影時に位相微分像生成部50で位相微分像を生成する際に用いられる各走査位置を、走査位置ズレ量算出56により算出されたズレ量を用いて補正する。減算処理部52は、本撮影時に生成された第1の位相微分像から、プレ撮影時に生成された第2の位相微分像を減算する。【選択図】図6
