Patent ID: 8570270
Filing Date: 2013-10-29
Classification: G02B

Abstract:
1. A display backlight unit comprising: a light guide configured to receive light from a light source, wherein the light comprises a first portion comprising more of a first color and less of a second color and a second portion comprising less of the first color and more of the second color, wherein the light guide is configured to cause the light to propagate from a first lateral edge towards a second opposite lateral edge of the light guide, and wherein the light guide is configured to cause the first portion to reach the second lateral edge and to retro-propagate from the second lateral edge back towards the first lateral edge; and a plurality of light-extracting elements configured to extract the second portion substantially prior to the second lateral edge and to extract the retro-propagating first portion of the light; wherein the plurality of light-extracting elements is configured to extract the first and second portions of the light to mix the first and second portions to provide substantially uniform color along an axis of the light guide.