PROBLEM TO BE SOLVED: To obtain a noiseless and fine phase differential image.SOLUTION: A radiography apparatus includes: an X-ray detector 13 which generates image data by detecting X-rays emitted from an X-ray source and transmitted through a subject H a grating unit 12 which is arranged between the X-ray source and the X-ray detector a phase differential image generating unit 40 which generates the phase differential image on the basis of the image data 51 and 52 obtained by the X-ray detector an unwrapping processing unit 41 which applies unwrapping processing to the phase differential image a trend removing unit 101 which removes predetermined frequency components from an offset image and a subject image by setting the unwrapping-processed phase differential image, obtained in the state of the presence of the subject, as the offset image and setting the unwrapping-processed phase differential image, obtained by photographing the subject, as the subject image and an offset removal unit 102 which removes noises except the predetermined frequency components by taking the difference between the offset image and the subject image, from which the predetermined frequency components are removed by the trend removing unit 101.COPYRIGHT: (C)2013,JPO&INPIT【課題】ノイズがない精細な位相微分画像を得る。【解決手段】X源から射出され、被検体Hを透過したX線を検出して画像データを生成するX線検出器13と、X線源とX線検出器との間に配置された格子部12と、X線検出器により得られた画像データ51,52に基づいて位相微分画像を生成する位相微分画像生成部40と、位相微分画像にアンラップ処理を施すアンラップ処理部41と、被検体がない状態で得られたアンラップ処理済み位相微分画像をオフセット画像、被検体を撮影して得られた前記アンラップ処理済み位相微分画像を被検体画像とし、オフセット画像及び被検体画像から所定周波数成分を除去するトレンド除去部101と、トレンド除去部101により、所定周波数成分が除去されたオフセット画像及び被検体画像の差分をとることにより、所定周波数成分以外のノイズを除去するオフセット除去部102と、を備える。【選択図】図24
