To correct the display characteristic of a display device.

A display state detecting part 1 detects whether a display device 5 for display is in a display state or not and a display time accumulating part 2 accumulates a display time only when the device is in the display state by a detection signal from the part 1. A display characteristic discriminating part 3 discriminates display characteristics for every an accumulated display time by a display time signal from the part 2 and when a display time becomes the threshold value of a prescribed accumulated display time, it transmits a control signal to a display characteristic correcting part 4. Then, the part 4 corrects the deterioration of luminance of the display device 5 by changing elements being establishment concerning the display to → elements suited to the accumulated display time.