PROBLEM TO BE SOLVED: To provide a technique for easily identifying the kind of a substance contained in an object with high accuracy by use of an image obtained from a tomograph or the like adopting a tomosynthesis method.SOLUTION: This apparatus identifies the substance present in an attention region inside a subject by use of count values obtained by distinguishing the energy of X-rays into a plurality of energy regions and performing photon counting and a subject image reconstructed by the count values. In the apparatus, a reference image (S1, S2) is created based on a count value obtained by imaging a substance having a uniform thickness and density, and a pixel value of the subject image is divided by a pixel value of the reference image in each pixel, so that the pixel values of the subject image are standardized (S3-S6). A scatter diagram is created from the standardized pixel values with an axis imparted with absorption information as one axis of two dimensions and with an axis imparted with beam hardening information of the X-rays as the other axis of the two dimensions (S8-S10). Identification information for identifying the kind of the substance present in an imaged portion of the subject is acquired from the scatter diagram (S111-S14).COPYRIGHT: (C)2013,JPO&INPIT【課題】トモシンセシス法を採用する断層装置等から得られる画像を使って、精度良く且つ簡便に対象物に含まれる物質の種類を同定する手法を提供する。【解決手段】X線のエネルギを複数のエネルギ領域に弁別して光子計数した計数値及びその計数値で再構成した被検体画像を用いて、被検体の中の注目部位に在る物質を同定する装置である。この装置では、厚さ及び密度の均一な物質を撮像した計数値に基づいて参照画像(S1,S2)が作成され、この参照画像の画素値で被検体画像の画素値を画素毎に除算して当該被検体画像の画素値が規格化される(S3~S6)。この規格化された画素値から、吸収情報を与えた軸を2次元の一方の軸に、且つ、当該2次元の他方の軸にX線のビームハードニング情報を与えた散布図が作成される(S8~S10)。この散布図から、被検体の撮像部分に在る物質の種類を同定するための同定情報が取得される(S111~S14)。【選択図】 図7
