Directional backlighting for display panels

摘要

Various embodiments are disclosed that relate to display panel backlight systems that output light with a narrower angular intensity distribution than a diffuse backlight. For example, one disclosed embodiment provides a backlight system comprising a wedge-shaped light guide comprising a thin end and a thick end, the thick end of the wedge-shaped light guide comprising a linear reflector with plurality of facets, and wherein the backlight system also comprises a plurality of light sources arranged along the thin end of the wedge-shaped light guide.

主权项

1. A backlight system for a display panel, the backlight system comprising:
a wedge-shaped light guide comprising a thin end opposite a thick end, the thick end of the wedge-shaped light guide comprising a cylindrical reflector with a plurality of reflecting facets, the cylindrical reflector being curved along a first direction extending between and connecting two opposing major faces at the thick end of the wedge-shaped light guide, and uncurved along a second direction extending between and connecting two opposing minor faces at the thick end of the wedge-shaped light guide; a plurality of light sources of first and second subsets arranged along the thin end of the wedge-shaped light guide, opposite the cylindrical reflector, wherein each light source of the first subset is configured to output light of a narrower emitter angle, and each light source of the second subset is configured to output light of a wider emitter angle, and wherein the light sources of the first subset and the light sources of the second subset are arranged in an alternating relation along the thin end of the wedge-shaped light guide; and a controller configured to switch between operating the backlight system in a narrow angle mode in which the first subset of light sources are in an on state and the second subset of light sources are in an off state, and operating the backlight system in a wide angle mode in which the second subset of light sources are in an on state.