Patent ID: 7936258

Claim:
A display system for a vehicle comprising: a display member that displays an information message, the information message including a background and an object that is displayed adjacent the background, the display member defines a surface from which the information message is displayed; a display surface light sensor that detects an ambient illuminance on the surface of the display member for calculating a reflected ambient luminance on the surface of the display member; a light noise sensor that detects a light noise condition within an area corresponding approximately to a forward area in front of the vehicle; a controller that calculates a total object luminance by adding a luminance of the object and the reflected ambient luminance without adding the light noise condition, the controller also calculates a total background luminance by adding a luminance of the background, the reflected ambient luminance, and the light noise condition, the controller changes legibility of the information message by changing each of the background and the object based on an actual contrast of the information message, which is a ratio between the total object luminance and the total background luminance, and a predetermined relationship between luminance and contrast.