Increasing dynamic range of display output

An electroluminescent display system for receiving a three-component input image signal having triplets of intensity values, the intensity values having at least an image range and a highlight range, the smallest intensity value of the highlight range being greater than the greatest intensity value of the image range, including:

• (a) an electro-luminescent display comprising:
• (i) a plurality of light-emitting elements for emitting red, green, and blue light and at least one additional light-emitting element for emitting at least one additional color of light, the luminance of the light being responsive to a current provided to each light-emitting element;
• (ii) one or more circuits for controlling the current to each light-emitting element, the circuits providing a current to each light-emitting element to cause each light-emitting element to produce a corresponding luminance value, wherein the corresponding luminance value of the at least one additional light-emitting element is greater than the corresponding luminance value of at least one of the red, green, or blue light-emitting elements at the same current;
• (b) one or more display drivers responsive to the received three-component input image signal for transforming the three-component input image signal to a four-or-more-component drive signal and providing the four-or-more-component drive signal to the one or more circuits to control the current to each light-emitting element;
• and
• (c) wherein the display driver(s) transforms at least one of the triplets having an intensity value within the image range to a four-or-more-component drive signal that produces a luminance less than the sum of the corresponding luminance values of the red, green and blue light-emitting elements and transforms at least one of the intensity values within a triplet having an intensity value within the highlight range to a four-or-more-component drive signal that produces a luminance greater than the sum of the corresponding luminance values of the red, green, and blue light-emitting elements.