Patent ID: 6521879
Filing Date: 2003-02-18
Classification: G09G,H05B

Abstract:
An apparatus comprising:a driven array of LEDs adapted and configured as a backlight for a flat panel display; said driven array of LEDs comprising a first LED string, having a first LED driver, a first string sensor LED and a plurality of first string viewing area component LEDs disposed therebetween, a second LED string, having a second LED driver, a second string sensor LED and a plurality of second string viewing area component LEDs disposed therebetween, and a third LED string, having a third LED driver, a third string sensor LED and a plurality of third string viewing area component LEDs disposed therebetween, wherein said pluralities of first, second and third string viewing area component LEDs are disposed within a viewing area that is substantially aligned with a display viewing window of a flat panel display, said pluralities of first, second, and third string viewing area component LEDs arranged and collectively configured to emit light to provide backlighting for the flat panel display, and wherein said first, second and third string sensor LEDs are positioned outside of the viewing area such that light emitted therefrom does not substantially contribute to the backlighting of the flat panel display; a light sensing assembly, having therein a photodetector positioned outside of the viewing area and adjacent the first, second and third string sensor LEDs, said photodetector adapted and configured for detecting light emitted, from outside said viewing area, by said first string sensor LED, said second string sensor LED, and said third string sensor LED; an optical feedback control which is adapted and configured to receive a detected light level signal from said photodetector and generate a commanded output signal in response thereto; and, an optical feedback line adapted and configured to carry said commanded output signal to said first LED driver, said second LED driver, and said third LED driver.