PURPOSE: To eliminate the flickering of an X-ray image via simple constitution by displaying the video signal of the first/inter-field through the field memory of a TV camera outputted on the timing of X-ray exposure and the video signal of the second inter-filed via the required adding treatment.

CONSTITUTION: The first field video signal outputted on the timing of X-ray exposure via a TV camera 5 in asynchronous motion with a cine-camera 6 is written in the first/inter-field of field memory 13 controlled by a synchronous detached circuit 10 and a timing controller 15 via an A/D converter 12. Said video signal is read from the memory 13 into the second inter-field and added to the video signal of the second field via an adder 17, thereby giving a frame video signal at the required level. This signal is supplied via a D/A converter and an X-ray image of simple constitution and free from flickering is displayed on a TV monitor.