Granted Patent B2

US 11,181,682 · App. 16/387,140 · Granted Nov 23, 2021

Inventors: Floris Maria Hermansz Crompvoets (Bunde, NL); Ernő Fancsali (Heusden-Zolder, BE)

Assignee: Lumileds LLC

G02B6/0073G02B6/0046G02B6/0055G02B6/0068

Abstract

Claims (29)

1. A light-emitting diode (LED) backlight system, comprising:

a plurality of backlight segments, each backlight segment including:

a light guide segment configured to guide light, the light guide segment having a smooth, flat top surface that is configured to emit at least some of the guided light from the light guide segment, the light guide segment extending between the top surface and a lower surface opposite the top surface, the light guide segment further defining a cavity that extends from the lower surface toward the top surface, the cavity having a top and sidewalls;

a sidelight emitting LED positioned in the cavity and configured to emit light into the light guide segment through the sidewalls of the cavity; and

an absorptive coating configured to prevent light from propagating between the light guide segment and any other light guide segment in the LED backlight system.

2. The LED backlight system of claim 1 , further comprising a sidewall in-coupling structure positioned between a sidewall of the cavity and the sidelight emitting LED.

3. The LED backlight system of claim 1 , further comprising 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.

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

5. The LED backlight system of claim 1 , wherein the lower surface is curved, the curved lower surface including four substantially triangular shaped faces.

6. The LED backlight system of claim 1 , wherein the lower surface is substantially smooth, the substantially smooth lower surface terminating in edges that have a lesser height at corners as compared to centers of respective edges.

7. The LED backlight system of claim 1 , wherein the lower surface intersects the sidewalls at a bottom edge of the sidewalls.

8. The LED backlight system of claim 1 , wherein each light guide segment has a substantially rectangular shape.

9. The LED backlight system of claim 1 , wherein the light guide segments are arranged in a rectilinear array.

10. The LED backlight system of claim 1 , wherein the plurality of backlight segments are located adjacent to one another in an array that extends along a plane.

11. The LED backlight system of claim 10 , wherein the flat top surface of the light guide segment is parallel to the plane.

12. The LED backlight system of claim 10 , wherein the top of the cavity is parallel to the plane.

13. The LED backlight system of claim 10 , wherein the sidewalls of the cavity are substantially orthogonal to the plane.

14. A light-emitting diode (LED) backlight system, comprising:

a first light guide segment, the first light guide segment configured to guide light, the first light guide segment having a smooth first flat top surface that is configured to emit at least some of the guided light from the first light guide segment, the first light guide segment extending between the first flat top surface and a first lower surface opposite the first flat top surface, the first light guide segment further defining a first cavity that extends from the first lower surface toward the first flat top surface, the first cavity having a first top and first sidewalls;

a first sidelight emitting LED positioned in the first cavity and configured to emit light into the first light guide segment through the first sidewalls of the first cavity;

a second light guide segment, the second light guide segment configured to guide light, the second light guide segment having a smooth second flat top surface that is configured to emit at least some of the guided light from the second light guide segment, the second light guide segment further defining a second cavity having a second top and second sidewalls;

a second sidelight emitting LED positioned in the second cavity and configured to emit light into the second light guide segment through the second sidewalls of the second cavity; and

an absorptive coating configured to prevent light from propagating between the first light guide segment and the second light guide segment.

15. A light-emitting diode (LED) backlight system, comprising:

a first light guide segment, the first light guide segment configured to guide light, the first light guide segment having a smooth first flat top surface that is configured to emit at least some of the guided light from the first light guide segment, the first light guide segment extending between the first flat top surface and a first lower surface opposite the first flat top surface, the first light guide segment further defining a first cavity that extends from the first lower surface toward the first flat top surface, the first cavity having a first top and first sidewalls;

a first sidelight emitting LED positioned in the first cavity and configured to emit light into the first light guide segment through the first sidewalls of the first cavity;

a second light guide segment, the second light guide segment configured to guide light, the second light guide segment having a smooth second flat top surface that is configured to emit at least some of the guided light from the second light guide segment, the second light guide segment further defining a second cavity having a second top and second sidewalls;

a second sidelight emitting LED positioned in the second cavity and configured to emit light into the second light guide segment through the second sidewalls of the second cavity; and

an absorptive coating configured to prevent light from propagating between the first light guide segment and the second light guide segment.

Assignments (6)