A display device that has a display screen is disclosed that has the ability to prevent reflections of the display screen from appearing on glass, without lowering the visibility of a display portion of the display screen. The brightness of the display color of either the background portion 31 on a display screen 30 or the background portion 31 of such one of display portions 32 and 33 as occupies the larger area of the lit portion of the display screen 30 is changed according to the control of a control switch 23. If the brightness of the display color of the background portion 31 is lowered (from the "thin light blue" to the "thick light blue", for example) at the nighttime, its reflection on the glass around a cabin 40 can be reduced without lowering the luminance of the display screen 30. Alternatively, the saturation or hue of the display color can be changed to obtain a similar effect.