Out-coupling structure for a light guide

1. A LED backlight system, comprising:

a plurality of backlight segments, each backlight segment supporting a sidelight emitting LED;

a light guide included in each backlight segment, with the light guide further defining a cavity having a top and sidewalls, with the sidelight emitting LED positionable in the cavity; and

at least one of a reflective layer and a top out-coupling structure positioned between the top of the cavity and the sidelight emitting LED,

wherein a sidewall in-coupling structure is formed or defined in the sidewalls of the cavity.

2. The LED backlight system of claim 1 , wherein the sidewall in-coupling structure comprises one or more of the following: 3 -dimensional scattering structures, defined or molded grooves, pyramids, notches, prisms and printed white dot patterns.

3. The LED backlight system of claim 2 , wherein the prisms define a Fresnel representation.

4. The LED backlight system of claim 1 , wherein the backlight segments are separated from each other by an optical barrier.

5. The LED backlight system of claim 4 , wherein the optical barrier separating the backlight segments is at least one of a reflective and absorptive coating.

6. The LED backlight system of claim 1 , wherein each of the plurality of backlight segments are positioned adjacent to at least one other backlight segment on a printed circuit board substrate.

7. The LED backlight system of claim 1 , wherein a reflective layer is not formed on the top out-coupling structure.

8. The LED backlight system of claim 1 , wherein the plurality of backlight segments are positioned adjacent to each other on a printed circuit board substrate.

9. The LED backlight system of claim 1 , wherein each sidelight emitting LED is centrally positioned in the respective backlight segment.