PROBLEM TO BE SOLVED: To provide a tomosynthesis imaging apparatus capable of shortening an imaging time and a method of operating the tomosynthesis imaging while suppressing an artifact of a tomographic image and performing tomosynthesis imaging while moving one X-ray tube. A tomosynthesis imaging apparatus has a radiation detector having an imaging surface for detecting radiation that has passed through a subject and capturing a projected image of the subject, and a plurality of radiation tubes having different irradiation angles of the radiation with respect to the imaging surface. Therefore, focus position control for switching the position of the focal point at which radiation is emitted is performed for a radiation source that selectively emits radiation from a plurality of radiation tubes toward a subject and at least one of the plurality of radiation tubes. And a radiation source control unit that changes the irradiation angle of the radiation with respect to the imaging surface of the radiation tube. [Selection diagram] FIG.【課題】断層画像のアーチファクトを抑制しつつ、１つのＸ線管を移動させながらトモシンセシス撮影を行う従来と比べて、撮影時間を短くすることが可能なトモシンセシス撮影装置及びその作動方法を提供する。【解決手段】トモシンセシス撮影装置は、被写体を透過した放射線を検出して被写体の投影画像を撮像する撮像面を有する放射線検出器と、撮像面に対する放射線の照射角度が異なる複数の放射線管を有しており、被写体に向けて、複数の放射線管から選択的に放射線を照射する放射線源と、複数の放射線管のうちの少なくとも１つについて、放射線が放射される焦点の位置を切り替える焦点位置制御を行って、放射線管の撮像面に対する放射線の照射角度を変化させる線源制御部と、を備えている。【選択図】図１２
