ILLUMINATION ASSEMBLY AND SYSTEM

• US 20070047254A1
• Filed: 08/25/2006
• Published: 03/01/2007
• Est. Priority Date: 08/27/2005
• Status: Active Grant

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Smith, Kenneth, Griffith, Richard, Thompson, D., Epstein, Kenneth, Schardt, Craig, Ostlie, Brian
• Granted Patent: US 7,695,180 B2
• Time in Patent Office: Days
• US Class Current: 362/607
• CPC Class Codes: G02B 19/0028 refractive and reflective surfaces, e.g. non-imaging catadioptric systems
• CPC Class Codes: G02B 19/0057 in the form of a laser diode array, e.g. laser diode bar semiconductor laser arrays with beam combining arrangement H01S5/4012
• CPC Class Codes: G02B 19/0066 in the form of an LED array
• CPC Class Codes: G02B 5/0242 by means of dispersed particles
• CPC Class Codes: G02B 5/0278 used in transmission
• CPC Class Codes: G02B 5/0284 used in reflection
• CPC Class Codes: G02B 5/0294 adapted to provide an additional optical effect, e.g. anti-reflection or filter
• CPC Class Codes: G02B 5/045 Prism arrays
• CPC Class Codes: G02B 6/0053 Prismatic sheet or layer; Brightness enhancement element, sheet or layer
• CPC Class Codes: G02F 1/133603 with LEDs
• CPC Class Codes: G02F 1/133606 including a specially adapted diffusing, scattering or light controlling members
• CPC Class Codes: G02F 1/133607 the light controlling member including light directing or refracting elements, e.g. prisms or lenses
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/48257 connecting the wire to a die pad of the item
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 33/58 Optical field-shaping elements

Abstract

Illumination assemblies and systems using same are disclosed. The illumination assembly can include a reflective substrate, and a light source unit including one or more light sources capable of producing illumination light. The assembly can further include a first light extraction surface including an azimuthal beam widening topography, where the first light extraction surface is positioned such that the light source unit is between the first light extraction surface and the reflective substrate. The first light extraction surface can face the light source unit.

Claims

1. An illumination assembly, comprising:

a reflective substrate;

a first light extraction surface comprising an azimuthal beam widening topography; and

a light source unit comprising one or more light sources capable of producing illumination light, wherein the light source unit is between the first light extraction surface and the reflective substrate, and wherein the first light extraction surface faces the light source unit.

2. The assembly of claim 1, wherein the first light extraction surface further comprises a polar beam widening topography.

3. The assembly of claim 1, wherein the first light extraction surface comprises an array of elongate continuous prisms occupying an x-y plane thereof, wherein each prism in the array comprises two inclined surfaces that meet to form a ridge, and wherein the ridges are substantially continuous and non-linear.

4. The assembly of claim 3, wherein the ridges undulate in the x-y plane.

5. The assembly of claim 3, wherein the inclined surfaces of the prisms are curved in a plane normal to the x-y plane.

6. The assembly of claim 3, wherein the inclined surfaces of the prisms are curved in a y-z plane normal to the x-y plane.

7. An illumination assembly, comprising:

a reflective substrate;

a first light extraction surface comprising an array of closely packed conical structures, wherein the array comprises substantially no flat land areas between the conical structures wherein a base of the conical structures lies in an x-y plane of the surface and an apex of the conical structures lies outside the x-y plane of the surface; and

a light source unit comprising one or more light sources capable of producing illumination light, wherein the light source unit is between the first light extraction surface and the reflective substrate, and wherein the apexes of the conical structures in the array on the first light extraction surface are directed toward the light source unit.

8. The assembly of claim 7, wherein the bases of the conical structures in the array are adjacent to one another.

9. The assembly of claim 8, wherein the conical structures have a cross-sectional shape selected from circular and elliptical in a plane parallel to the x-y plane.

10. The assembly of claim 7, wherein the base of the conical structures is selected from circular, elliptical and hexagonal.

11. The assembly of claim 7, wherein the apexes of the conical structures lie outside a plane normal to the x-y plane.

12. An illumination assembly, comprising:

a reflective substrate;

a first light extraction surface comprising at least one faceted surface, wherein the faceted surface has an in-plane curvature in the x-y plane; and

a light source unit comprising one or more light sources capable of producing illumination light, wherein the light source unit is between the first light extraction surface and the reflective substrate, and wherein the first light extraction surface faces the light source unit.

13. The assembly of claim 12, wherein the at least one faceted surface lies on individual light diverting elements on the light extraction surface.

14. The assembly of claim 12, wherein the light extraction surface comprises a plurality of faceted surfaces, and wherein the faceted surfaces are distributed among a plurality of light diverting elements on the light extraction surface.

15. The assembly of claim 12, wherein the curvature is sufficient to produce a difference of azimuthal angle Δ

β

of at least 15°

with respect to a beam normally incident on the light extraction surface.

16. An illumination assembly, comprising:

a reflective substrate;

a first light extraction surface comprising means for producing a difference of azimuthal angle Δ

β

of at least 15°

with respect to a beam normally incident on the light extraction surface; and

a light source unit comprising one or more light sources capable of producing illumination light, wherein the light source unit is between the first light extraction surface and the reflective substrate, and wherein the first light extraction surface faces the light source unit.

17. The assembly of claim 16, wherein the means for producing a difference of azimuthal angle comprises a plurality of non-curved facets arranged at varying angles in a x-y plane of the light extraction surface.

18. The assembly of claim 16, wherein the means for producing a difference of azimuthal angle comprises at least one light diverting element having at least one facet with a curvature in the x-y plane.

19. The assembly of claim 18, wherein the facets lie on multiple light diverting elements.

20. A directly illuminated display system, comprising:

a display panel comprising an illumination side; and

an illumination assembly disposed to the illumination side of the display panel, the illumination assembly comprising;

a reflective substrate;

a light source unit comprising one or more light sources capable of producing illumination light; and

a first light extraction surface between the first light extraction surface and the reflective substrate, wherein the first light extraction surface faces the light source unit, and wherein the first light extraction surface has an azimuthal beam widening topography.

21. The system of claim 20, wherein the first light extraction surface comprises an array of elongate continuous prisms occupying an x-y plane thereof, wherein each prism in the array comprises two inclined surfaces that meet to form a ridge, and wherein the ridges are substantially continuous and undulate in the x-y plane, wherein the ridges lie outside an x-z plane normal to the x-y plane, wherein the width of the prisms undulates along the y-direction and the height of the prisms undulates along a z-direction normal to the x-y plane.

22. The system of claim 21, wherein the light source unit comprises an array of LEDs comprising rows of LEDs oriented substantially along the ridges of the prisms on the first light extraction surface.

23. The system of claim 22, wherein the LEDs comprise side fired LEDs.

24. The system of claim 21, wherein the inclined surfaces of the prisms are curved in a plane normal to the x-y plane.

25. The system of claim 21, wherein the inclined surfaces of the prisms are curved in a y-z plane normal to the x-y plane.

26. The system of claim 20, wherein the light source unit comprises an array of LEDs.

27. The system of claim 20, further comprising a diffuser layer positioned such that the first light extraction surface is between the diffuser layer and the light source unit.

28. The system of claim 27, further comprising a reflective polarizer between the diffuser layer and the first light extraction surface.

29. The system of claim 20, further comprising a reflective polarizer, wherein the first light extraction surface is between the reflective polarizer and the light source unit.

30. The system of claim 20, wherein the light source unit comprises a first light source capable of generating red light, a second light source capable of generating green light, and a third light source capable of generating blue light.