CRT DISPLAY DEVICE

PURPOSE:To prevent the deterioration in the luminous body of a display part without allowing a user of the CRT device to be conscious of the deterioration by having a control signal generating circuit which generates the deflection control signal to changing a deflection signal with time. CONSTITUTION:The data to be displayed is transmitted from a computer to a display memory 1 and is successively stored into a memory. The data of this memory is taken into a video signal generating circuit 2 and generates the video signal in accordance with the synchronizing signal from a synchronizing circuit 4 and inputs the same to a CRT 3. The data from the computer is then displayed on the CRT 3. The character on the display screen moves to the position shown by a broken line by spending one hour and returns to the home position in one hour when a staircase signal changing in voltage in synchronization with the sweep period of the deflection signal is impressed as a bias voltage to a vertical deflecting circuit 5 and a horizontal deflecting circuit 6 in such a manner, for example, the position moves by 0.5 character space per one hour. The deterioration of the luminous body of the specific position in the display part is prevented in this way.