LUMINAIRE HAVING AN ASYMMETRICAL LIGHT DISTRIBUTION PATTERN

• US 20190324188A1
• Filed: 05/28/2019
• Published: 10/24/2019
• Est. Priority Date: 09/12/2016
• Status: Active Grant

• Current Assignee: Lumileds LLC (Apollo Global Management, Inc.)
• Original Assignee: Lumileds LLC (Apollo Global Management, Inc.)
• Inventors: Den Breejen, Jeroen, Diana, Frederic S.
• Granted Patent: US 10,809,447 B2
• Time in Patent Office: Days
• CPC Class Codes: F21S 2/00 Systems of lighting devices, not provided for in main groups F21S4/00 - F21S10/00 or F21S19/00, e.g. of modular construction
• CPC Class Codes: F21S 8/085 of high-built type, e.g. street light
• CPC Class Codes: F21S 8/086 with lighting device attached sideways of the standard, e.g. for roads and highways
• CPC Class Codes: F21W 2131/103 of streets or roads
• CPC Class Codes: F21Y 2105/12 characterised by the geometrical disposition of the light-generating elements, e.g. arranging light-generating elements in differing patterns or densities
• CPC Class Codes: F21Y 2105/18 annular; polygonal other than square or rectangular, e.g. for spotlights or for generating an axially symmetrical light beam
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: G02B 6/00 Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
• CPC Class Codes: G02B 6/0021 for housing at least a part of the light source, e.g. by forming holes or recesses
• CPC Class Codes: G02B 6/0031 Reflecting element, sheet or layer
• CPC Class Codes: G02B 6/0036 2-D arrangement of prisms, protrusions, indentations or roughened surfaces
• CPC Class Codes: G02B 6/0043 provided on the surface of the light guide
• CPC Class Codes: G02B 6/0055 Reflecting element, sheet or layer
• CPC Class Codes: G02B 6/0063 for extracting light out both the major surfaces of the light guide
• CPC Class Codes: G02B 6/0068 Arrangements of plural sources, e.g. multi-colour light sources
• CPC Class Codes: G02B 6/0073 Light emitting diode [LED]
• CPC Class Codes: G02B 6/0091 of the light source relative to the light guide G02B6/0021 takes precedence

Abstract

An apparatus is disclosed including a light guide and a plurality of light emitting diodes (LEDs). The light guide includes a rear portion including a first edge, a second edge, and a rear edge. The first edge meets the rear edge at a first obtuse angle, and the second edge meets the rear edge at a second obtuse angle. The plurality of light emitting diodes (LEDs) disposed on the first edge, the second edge, and the rear edge, and it is arranged to produce an asymmetric light distribution pattern including a rear light emission and a forward light emission having a greater peak intensity than the rear light emission.

Claims

1. An apparatus, comprising:

a light guide including a light exit surface and a reflection surface opposite the light exit surface;

a plurality of light emitting diodes (LEDs) positioned around a perimeter of the light guide and configured to direct light into the light guide; and

a plurality of Gaussian dots positioned on the light guide and configured to extract light out of the light guide, the plurality of LEDs and the plurality of Gaussian dots being positioned such that the extracted light is distributed asymmetrically around the perimeter of the light guide.

2. The apparatus of claim 1, wherein the light exit surface defines a first plane generally orthogonal to the light exit surface, such that the extracted light includes more light on a first side of the first plane than on a second side, opposite the first side, of the first plane.

3. The apparatus of claim 2, wherein the plurality of Gaussian dots are distributed non-uniformly on the light guide.

4. The apparatus of claim 3, wherein the plurality of Gaussian dots are distributed to have a higher density on the first side of the first plane than on the second side of the first plane.

5. The apparatus of claim 3, wherein the plurality of Gaussian dots are distributed to have a density that varies with distance to a front edge of the light guide, the front edge being a portion of the perimeter of the light guide that is spaced farthest away from the first plane on the first side of the first plane.

6. The apparatus of claim 1, wherein the Gaussian dots are positioned on the light exit surface of the light guide.

7. The apparatus of claim 1, wherein the Gaussian dots are positioned on the reflection surface of the light guide.

8. The apparatus of claim 1, wherein the Gaussian dots are printed on the light guide.

9. The apparatus of claim 1, wherein the Gaussian dots are printed with ink on the light guide using screen printing.

10. The apparatus of claim 1, wherein the Gaussian dots includes diffusing particles in a base material, the diffusing particles and the base material differing in refractive index.

11. The apparatus of claim 10, wherein the base material includes at least one of epoxy or silicone.

12. The apparatus of claim 10, wherein the diffusing particles include at least one of silicon dioxide or titanium dioxide.

13. The apparatus of claim 1, wherein the plurality of LEDs are distributed uniformly around the perimeter of the light guide.

14. The apparatus of claim 1, wherein the plurality of LEDs are distributed non-uniformly around the perimeter of the light guide.

15. A method, comprising:

producing light with a plurality of light emitting diodes (LEDs) positioned around a perimeter of a light guide, the light guide including a light exit surface and a reflection surface opposite the light exit surface;

directing the produced light into the light guide;

directing a first portion of the light, within the light guide, to strike the light exit surface;

directing a second portion of the light, within the light guide, to reflect off the reflection surface and strike the light exit surface; and

extracting, with a plurality of Gaussian dots positioned on the light exit surface, at least some of the first portion of the light and at least some of the second portion of the light, the plurality of LEDs and the plurality of Gaussian dots being positioned such that the extracted light is distributed asymmetrically around the perimeter of the light guide.

16. The method of claim 15, wherein the light exit surface defines a first plane generally orthogonal to the light exit surface, such that the extracted light includes more light on a first side of the first plane than on a second side, opposite the first side, of the first plane.

17. The method of claim 16, wherein the plurality of Gaussian dots are distributed non-uniformly on the light exit surface.

18. The method of claim 16, wherein the plurality of Gaussian dots are distributed to have a higher density on the first side of the first plane than on the second side of the first plane.

19. The method of claim 16, wherein the plurality of Gaussian dots are distributed to have a density that varies with distance to a front edge, the front edge being a portion of the perimeter of the light guide that is spaced farthest away from the first plane on the first side of the first plane.

20. An apparatus, comprising:

a light guide including a light exit surface and a reflection surface opposite the light exit surface, the light exit surface defining a first plane generally orthogonal to the light exit surface;

a plurality of light emitting diodes (LEDs) positioned around a perimeter of the light guide and configured to direct light into the light guide; and

a plurality of Gaussian dots positioned on the light exit surface and configured to extract light out of the light guide, the plurality of LEDs and the plurality of Gaussian dots being positioned such that the extracted light includes more light on a first side of the first plane than on a second side, opposite the first side, of the first plane.