Patent ID: 6608614
Filing Date: 2003-08-19
Classification: G02B,G09G,H05B

Abstract:
A backlight for a liquid-crystal display, comprising:a first light-emitting diode (LED) array that provides light with a first chromaticity; a second LED array that provides light with a second chromaticity that is different from the first chromaticity, wherein the second LED array includes at least one LED; a combining element that combines the light from the first LED and second LED arrays and directs the combined light toward the liquid crystal display; and a control system that is operationally connected to the second LED array, wherein the control system selectively varies the brightness of the at least one LED independent of the brightness of the first LED array, thereby adjusting the chromaticity of the combined light, wherein the control system includes a processor that calculates the difference between a target chromaticity of the combined light and an actual chromaticity of the combined light, the control system selectively varying the brightness of the at least one LED to reduce said difference.