Lighting engineers at Ford Motor Co, are sprucing up the 2005 Mustang with an instrument cluster in the dashboard that can be backlit by any of 125 possible colors.
And drivers get to choose the color. The system relies on three LEDs, each generating a different color — red, green, and blue. Three acrylic light pipes carry light to the sides of the gages, where it mixes to create the final color. LEDs cannot be dimmed like conventional bulbs, so the intensity of each color is controlled by pulse-width modulation, which turns each LED on and off at rates too quick for detection by the human eye. The intensity of each color is determined by the ratio of an LED on and off times. Ford gives users six preset options — green, blue, purple, white, orange, and red. But drivers can personalize the car by adjusting intensity on the three LEDs to produce up to 125 colors.