| 摘要 |
<p>High-precision phase contrast radiological images are generated by appropriate exposure control. A radiation imaging system (10) is provided with: a first grid (31); a second grid (32) having periods that substantially match the pattern periods of a radiological image formed by radiation that has passed through the first grid, and disposed in a plurality of relative positions where the phases differ to each other with respect to the radiological image; a radiation image detector (30) that detects the radiation image masked by the second grid; a dose detection unit (35) that is positioned downstream from the second grid, and that detects the dose of incident radiation; and a control unit (20) that controls exposure. The control unit (20) controls exposure such that, in a plurality of exposures in which the second grid (32) is disposed in the relative positions that differ to each other, exposure continues in the first exposure until the dose of radiation detected by the dose detection unit (35) reaches a preset threshold amount, and such that exposure continues in the second exposure onward until the exposure time required in the first exposure has elapsed.</p> |
