PURPOSE: To brought plural radiation generators under the control of one controller, by measuring the dosage of radiation from a radiation source directly by a solid-state dosimeter, and feeding its output back to the controller and determining specific irradiation condition.

CONSTITUTION: When a standard voltage is applied to the side of an X-ray generator 1 and X-rays are radiated from an X-ray tube 3, the solid-state dosimeter 5 fitted to the X-ray tube 3 measures its dosage directly. This measured value is stored in a storage circuit 14 and an arithmetic circuit 15 calculates the control condition regarding a tube voltage, tube current, etc., within an energy range required for use and sends out a corresponding correction control signal to the generator 1 to radiate a desired amount of radiation from the X-ray tube 3. Consequently, the radiation generator is standardized and plural radiation generators are brought under the control of one controller; when the duty ratio of each X-ray generator is 30W50%, the apparently continuous use of, for example, three X-ray generators is made possible.