CONSTITUTION: In an X-ray imaging device 40, an EIvalue is set. A CPU 14 acquires plural EI values each of which indicates a dose of radiation which transmitted through a patient during imaging by the X-ray imaging device and calculates plural DI values each of which indicates a deviation to the EIvalue of the acquired EI value. The CPU14 also displays an EI/DI graph indicating a relationship of the plural EI values and plural DI values which are acquired or calculated, on a screen SC1 of a display device 20, and receives a slider movement operation for updating the EIvalue, related to the display of the EI/DI graph.EFFECT: Operation ability for setting the EIvalue to a proper value is improved, and in addition, management of radiation dose of an X-ray imaging device 40 is facilitated.SELECTED DRAWING: Figure 1
