Display device for motor vehicles

Display device for displaying a succession of images in a motor vehicle, comprising

• a graphic-capable transflective dot matrix LCD (19);
• means (21) for backlighting said LCD, and
• a Liquid Crystal Display (LCD) control circuit (17), having an output connected to and controlling said LCD, said control circuit including
• driver stages electrically activating matrix dots or pixels (22,25) of said LCD,
• memory means in said control circuit for representing information as one of said images on said LCD by brightness contrast including instructions to said drivers for applying a voltage to certain activated matrix dots, as opposed to the remaining non-activated matrix dots, to which no voltage is applied,
• means in said control circuit for comparing, in each successive image to be displayed on said LCD, the number of activated matrix dots or pixels to the number of non-activated matrix dots or pixels, in order to use the result of this comparison as a factor in automatic selection of a contrast mode, and
• means (27) for selectively setting said display, under conditions of bright ambient lighting, to a positive contrast mode in which a majority of pixels in said image are bright, thereby assuring adequate legibility of said information, and under conditions of dim ambient lighting, to a negative contrast mode in which a majority of pixels in said image are dark, thereby preventing dazzling of a vehicle operator.