DISPLAY DEVICE

PURPOSE: To handle a video signal with extremely wide range of scanning frequency and to perform display with the optimum luminance corresponding to the video signal by suppressing a part to be adjusted from increasing. CONSTITUTION: This device comprises a scan converter 1 to which input video signals 100 and input synchronizing signals 200 with various kinds of standard are inputted and which converts them to desired signals of horizontal and vertical scanning line frequencies, a video processing circuit 20 which inputs an output video signal 400 from the scan converter 1 and performs processing such as bright control, contrast control, etc., a variable gain video output circuit 26 which inputs the output signal of the video processing circuit 20 and amplifies it to signal voltage amplitude by which a picture tube (CRT) 4 can be driven and moreover, varies a gain by a control signal from the scan converter 1, a deflection circuit 3 which inputs an output synchronizing signal from the scan converter 1, and the picture tube (CRT) 4.