Patent ID: 8085238
Filing Date: 2011-12-27
Classification: G09G

Abstract:
1. A backlight for illuminating the back of a display section, comprising: a plurality of light sources disposed in positions corresponding to a display area of the display section, each of the light sources extending lengthwise from a first end to a second end opposing the first end; a diffusion member configured to transmit light from the light sources to the display section; a photo-sensor; a light guiding member configured to introduce the light from the light sources to the photo-sensor for detection; and an arithmetic operation processing section configured to calculate luminance or chromaticity of each of the light sources from the luminance or chromaticity detected by the photo-sensor, in which the light sources are grouped into a first group and a second group, in which the first group includes a first plurality of light sources and the second group includes a second plurality of light sources, the photo-sensor includes a pair of photo-sensor elements, and the light guiding member includes a first light guiding element and a second light guiding element, in which the first light guiding element is disposed at the first ends of light sources of the first plurality of light sources so first light fluxes, respectively, from the first ends of the first plurality of light sources enter the first light guiding element and is shaped to reflect the first light fluxes entering the first light guiding element at different angles from one another so as to introduce the reflected first light fluxes to only one photo-sensor element of the photo-sensor elements for detection, and in which the second light guiding element is disposed at the first ends of light sources of the second plurality of light sources so second light fluxes, respectively, from the first ends of the second plurality of light sources enter the second light guiding element and is shaped to reflect the second light fluxes entering the second light guiding element at different angles from one another so as to introduce the reflected second light fluxes to only another photo-sensor element of the photo-sensor elements for detection, such that during operation the reflected first light fluxes from the first plurality of light sources entering the first light guiding element are introduced to the one photo-sensor element of the photo-sensor elements for detection and none of the reflected second light fluxes from the second plurality of light sources entering the second light guiding element are introduced to the one photo-sensor element of the photo-sensor elements, and the reflected second light fluxes from the second plurality of light sources entering the second light guiding element are introduced to the another photo-sensor element of the photo-sensor elements for detection and none of the reflected first light fluxes from the first plurality of light sources entering the first light guiding element are introduced to the another photo-sensor element of the photo-sensor elements for detection, wherein the one and the another photo-sensor elements are attached to the light guiding member to detect, respectively, only the reflected first light fluxes and the reflected second light fluxes.