US Patent 10345505 Multibeam diffraction grating-based color backlighting

Multibeam diffraction grating-based color backlighting includes a plate light guide, a multibeam diffraction grating at a surface of the plate light guide, and light sources laterally displaced from one another in a direction corresponding to a propagation axis of the plate light guide. The light sources produce light of different colors. The plate light guide is to guide light from the light sources. The multibeam diffraction grating is to couple out a portion of the guided light using diffractive coupling as a plurality of light beams of different colors in a plurality of different principal angular directions.