BigPatents India

The radiography system includes an imaging device for imaging the patient by utilizing X-rays and a detecting unit for detecting the exposure dose which the patient receives during the radiography. The detecting unit (80) comprises a first lookup table (804) in which values of a dose rate are recorded in association with the values of a tube voltage of an X-ray tube; a second lookup table (806) in which values of the area of an X-ray field are recorded in association with the positions of blades included in a collimator; and a calculating device (802) for retrieving the value of the dose rate which is associated with a current value of the tube voltage from the first lookup table, retrieving the value of the area of the X-ray field which is associated with the positions of the blades included in the collimator from the second lookup table, and calculating the product of the dose rate, the area of the X-ray field, the tube current of the X-ray tube, and an X-ray irradiation time.