Lighting system

• US 10,641,438 B2
• Filed: 09/09/2015
• Issued: 05/05/2020
• Est. Priority Date: 09/17/2014
• Status: Active Grant

• Current Assignee: Koninklijke Philips N.V.
• Original Assignee: Koninklijke Philips N.V.
• Inventors: Hikmet, Rifat Ata Mustafa, van Bommel, Ties, Hohn, Roman, Schug, Josef Andreas
• Primary Examiner(s): Mai, Anh T
• Assistant Examiner(s): Fallahkhair, Arman B
• Application Number:
  US15/510,616
• Publication Number:
  US 20170254489A1
• Time in Patent Office: 1,700 Days
• CPC Class Codes: F21K 9/64 using wavelength conversion means distinct or spaced from the light-generating element, e.g. a remote phosphor layer
• CPC Class Codes: F21S 41/16 Laser light sources
• CPC Class Codes: F21S 41/176 Light sources where the light is generated by photoluminescent material spaced from a primary light generating element
• CPC Class Codes: F21V 13/14 the elements being filters or photoluminescent elements, reflectors and refractors
• CPC Class Codes: F21V 29/502 characterised by the adaptation for cooling of specific components
• CPC Class Codes: F21V 5/04 of lens shape
• CPC Class Codes: F21V 9/45 by adjustment of photoluminescent elements
• CPC Class Codes: F21Y 2115/30 Semiconductor lasers
• CPC Class Codes: G02B 26/105 with one or more pivoting mirrors or galvano-mirrors G02B26/101 takes precedence
• CPC Class Codes: G03B 21/16 Cooling; Preventing overheating
• CPC Class Codes: G03B 21/204 using secondary light emission, e.g. luminescence or fluorescence using different colours G03B33/00; if related to video signals H04N9/3197

Abstract

Proposed is a lighting system comprising: at least one laser adapted to output light; a pixelated luminous screen for emitting light when excited by incident light; and at least one optical component adapted to redirect and distribute light from the at least one laser to the pixelated luminous screen. The pixelated luminous screen comprises: a plurality of luminous pixels arranged adjacent each other with separated side edges, each pixel comprising luminous material; and a heat sink formed from thermally conductive material. The heat sink is positioned between the plurality of luminous pixels such that it contacts the adjacent side edges of the pixels.

Claims

1. A lighting system comprising:

at least one laser to output light;

a pixelated luminous screen to emit light when excited by incident light, wherein the laser and the pixelated luminous screen are fixed in position relative to one another; and

at least one optical component to redirect light from the at least one laser to the pixelated luminous screen, wherein the pixelated luminous screen comprises;

a plurality of luminous pixels arranged with separated side edges, each of the luminous pixels comprising luminous material; and

a heat sink formed from thermally conductive material, the heat sink being positioned between the plurality of luminous pixels such that it contacts the separated side edges of the luminous pixels, wherein each of the plurality of luminous pixels comprises;

a front light output surface to output light; and

a rear surface opposite the front light output surface, wherein the heat sink at least partially covers the rear surface of each of the plurality of luminous pixels, and wherein the heat sink comprises a plurality of apertures to enable light to pass therethrough and be incident on the rear surface of each of the plurality of luminous pixels and, wherein an at least partially transparent layer at least partially covers the front light output surface of each of the plurality of luminous pixels.

2. The lighting system of claim 1, wherein the front light output surface of the plurality of luminous pixels is non-planar.

3. The lighting system of claim 1, wherein at least some of the side edges of the plurality of luminous pixels are tapered so that the front light output surface area of a luminous pixel is greater than the rear surface area.

4. The lighting system of claim 1, wherein the partially transparent layer is non-planar.

5. The lighting system of claim 1, wherein the at least partially transparent layer comprises an array of lenticular structures.

6. The lighting system of claim 1, wherein the at least partially transparent layer is formed from a material having a thermal conductivity higher than 2 W·

m<sup>−

1</sup>·

K<sup>−

1</sup>.

7. The lighting system of claim 1, wherein at least two of the plurality of luminous pixels comprise the same luminous material.

8. The lighting system of claim 1, wherein at least one of the plurality of luminous pixels further comprises an at least partially transparent non-luminous material.

9. The lighting system of claim 1, wherein at least one of the plurality of luminous pixels further comprises a reflective material.

10. The lighting system of claim 1, wherein the plurality of luminous pixels are of different shapes or are of different sizes.

11. The lighting system of claim 1, further comprising:

first and second lasers adapted to output first laser light and second laser light, respectively; and

a plurality of optical components adapted to redirect the first laser light and the second laser light to different sets of luminous pixels of the pixelated luminous screen.

12. The lighting system of claim 1 wherein the thermal conductivity of the thermally conductive material is higher than 10 W·

m<sup>−

1</sup>·

K<sup>−

1</sup>.

13. A method of manufacturing a pixelated luminous screen for a lighting system having at least one laser adapted to output light and at least one optical component adapted to redirect light from the at least one laser to the pixelated luminous screen, the method comprising:

providing a plurality of luminous pixels arranged with separated side edges, wherein each of the plurality of luminous pixels comprises a front light output surface to output light, and a rear surface opposite the front light output surface, and luminous material, wherein the laser and luminous pixels are fixed in position relative to one another;

forming a heat sink from thermally conductive material such that heat sink at least partially covers the rear surface of each of the plurality of luminous pixels and is positioned between the plurality of luminous pixels such that it contacts the adjacent side edges of the luminous pixels; and

forming a plurality of apertures in the heat sink, to enable light to pass therethrough and be incident on the rear surface of each of the plurality of luminous pixels; and

providing an at least partially transparent layer that at least partially covers the front light output surface of each of the plurality of luminous pixels.

14. The method of claim 13, wherein the front light output surface of the plurality of luminous pixels is non-planar.

15. The method of claim 13, wherein at least some of the side edges of the plurality of luminous pixels are tapered so that the front light output surface area of a luminous pixel is greater than the rear surface area.

16. The method of claim 13, wherein the partially transparent layer is non-planar.

17. The method of claim 13, wherein the at least partially transparent layer comprises an array of lenticular structures.

18. The method of claim 13, wherein the at least partially transparent layer is formed from a material having a thermal conductivity higher than 2 W·

m−

1·

K−

1.

19. The method of claim 13, wherein at least two of the plurality of luminous pixels comprise the same luminous material.

20. The method of claim 13, wherein at least one of the plurality of luminous pixels further comprises an at least partially transparent non-luminous material.