Bidirectional LED Backlight For In-Vehicle LCD Displays

摘要

A backlight for liquid crystal displays which directs light to the general areas where observers' heads and eyes are located. In particular, the backlight is designed to direct light toward the driver and passenger positions in an automobile or other vehicle in such a way that the amount of light directed to either person can be varied independently.

主权项

1. A backlight for providing independently controlled illumination of a liquid crystal display to a first observer at a location in front of the liquid crystal display on a first side of a centerline of the liquid crystal display and to a second observer at a location in front of the liquid crystal display on a an opposite side of the centerline of the liquid crystal display, comprising:
a planar substrate; a first array of light emitting diodes mounted across the planar substrate, having a light output directed at an angle toward the location of the first observer on the first side of the centerline of the liquid crystal display; a second array of light emitting diodes mounted across the planar substrate, having a light output directed at an angle toward the location of the second observer on the opposite side of the centerline of the liquid crystal display; and a diffuser in front of the first array of light emitting diodes and second array of light emitting diodes; wherein a brightness of the first array of light emitting diodes is independently controllable from a brightness of the second array of light emitting diodes.