| 摘要 |
<p>The invention concerns a backlighting device, with several luminance levels, for transmission display screen (12). The device comprises light sources arranged in a housing (14) between a front translucent wall consisting of a diffusing screen (20) and a rear wall (24). The light sources, selected on the basis of the desired luminance level, are mosaics (24, 28) of light-emitting diodes (26, 30) placed immediately behind the diffusing screen with, for the highest luminance level, a first mosaic (24) of light-emitting diodes providing day time illumination and, for the lowest luminance level, a second mosaic (28) of light-emitting diodes providing night time illumination lighting. The invention is applicable to illumination box for transmission display screens.</p> |
