X-ray imaging apparatus and x-ray imaging method

An X-ray imaging apparatus comprising:

• an estimation unit adapted to estimate a cumulative exposure dose of X-rays irradiated onto an object;
• a remaining exposure tolerance dose calculation unit adapted to calculate a remaining exposure tolerance dose, using a difference between a tolerated maximum exposure dose and the cumulative exposure dose;
• an X-ray irradiation tolerance period calculation unit adapted to calculate an X-ray irradiation tolerance period, using a difference between a predetermined scheduled X-ray irradiation period and an actual irradiation period of X-rays irradiated onto the object;
• an X-ray irradiation reference dose calculation unit adapted to calculate an X-ray irradiation reference dose per unit time that will form a basis of X-ray irradiation, based on the remaining exposure tolerance dose and the X-ray irradiation tolerance period;
• and
• a control unit adapted to control X-ray irradiation onto the object by setting an X-ray irradiation dose per unit time within the X-ray irradiation tolerance period, based on the X-ray irradiation reference dose,
• wherein when the difference between the X-ray irradiation reference dose per unit time and a minimum X-ray irradiation dose per unit time required is less than a predetermined reference, the control unit sets an X-ray irradiation dose per unit time within the X-ray irradiation tolerance period to the minimum X-ray irradiation dose per unit time.