Multi-Layer Polymeric Lens and Unitary Optic Member for LED Light Fixtures and Method of Manufacture

• US 20140268762A1
• Filed: 03/15/2013
• Published: 09/18/2014
• Est. Priority Date: 03/15/2013
• Status: Active Grant

• Current Assignee: IDEAL Industries Lighting, LLC (Ideal Industries Incorporated)
• Original Assignee: CREE Incorporated (Wolfspeed, Inc.)
• Inventors: Raleigh, Craig, Wilcox, Kurt S.
• Granted Patent: US 10,400,984 B2
• Time in Patent Office: Days
• US Class Current: 362/244
• CPC Class Codes: B29C 45/16 Making multilayered or multicoloured articles B29C45/0062 takes precedence; feeding colouring materials into the injection unit B29C45/1816
• CPC Class Codes: B29D 11/0074 Production of other optical elements not provided for in B29D11/00009- B29D11/0073
• CPC Class Codes: B29K 2083/005 LSR, i.e. liquid silicone rubbers, or derivatives thereof
• CPC Class Codes: B29K 2995/0031 Refractive
• CPC Class Codes: B29L 2011/0016 Lenses
• CPC Class Codes: F21V 5/007 Array of lenses or refractors for a cluster of light sources, e.g. for arrangement of multiple light sources in one plane combination of two or more refractors F21V5/008
• CPC Class Codes: F21V 5/04 of lens shape
• CPC Class Codes: F21Y 2105/10 comprising a two-dimensional array of point-like light-generating elements
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]

Abstract

A unitary optic member for directing light from a plurality of LED light sources on a board beneath the optic member, the optic member having a plurality of lens portions surrounded by and interconnected by a non-lens portion and comprising: a first molded polymeric layer forming (a) the non-lens portion and (b) an outermost layer of each of the lens portions, the outermost layer of each lens portion forming a pocket-space at such lens portion; and for each lens portion, a second molded polymeric layer overmolded onto the first polymeric layer within the corresponding pocket-space. The invention includes an LED light fixture with such a unitary optic member. Another aspect of the invention is a multi-layer polymeric lens for directing light from an LED light source, the lens defining a lens optical footprint and at least one of the polymeric layers being less than coextensive with the lens optical footprint.

Claims

1. A unitary optic member for directing light from a plurality of LED light sources in spaced relationship to one another on a board beneath the optic member, the optic member having a plurality of lens portions each for directing light from one of the plurality of LED light sources, the lens portions being surrounded by and interconnected by a non-lens portion, the optic member comprising:

a first molded polymeric layer forming (a) the non-lens portion and (b) an outermost layer of each of the lens portions, the outermost layer of each lens portion forming a pocket-space at such lens portion; and

for each lens portion, a second molded polymeric layer overmolded onto the first polymeric layer within the corresponding pocket-space.

2. The unitary optic member of claim 1 wherein the first and second layers are of different polymeric materials.

3. The unitary optic member of claim 2 wherein the first layer is an acrylic layer and the second layer is an LSR layer.

4. The unitary optic member of claim 3 wherein the second layer is the innermost layer.

5. The unitary optic member of claim 1 wherein the first molded polymeric layer is injection-molded.

6. The unitary optic member of claim 1 wherein the first molded polymeric layer is thermoformed.

7. The unitary optic member of claim 1 wherein each of the lens portions further includes a third molded polymeric layer overmolded onto the second polymeric layer within the corresponding pocket-space, the third molded polymeric layer being the innermost layer.

8. The unitary optic member of claim 7 wherein the third layer is an LSR layer.

9. The unitary optic member of claim 1 wherein the two layers have different indices of refraction.

10. The unitary optic member of claim 9 wherein the second layer is an LSR layer.

11. A unitary optic member for directing light from a plurality of LED light sources in spaced relationship to one another on a board beneath the optic member, the optic member having a plurality of lens portions each for directing light from one of the plurality of LED light sources, the lens portions being surrounded by and interconnected by a non-lens portion, the optic member comprising:

a molded polymeric layer forming an outermost layer of each of the lens portions and forming non-lens portion therebetween; and

for each lens portion, another molded polymeric layer, the polymeric layers being overmolded to one another.

12. The unitary optic member of claim 11 wherein the molded polymeric layers are of different polymeric materials.

13. The unitary optic member of claim 12 wherein the layer forming the outermost layer and the non-lens portion is an acrylic layer and the other layer is an LSR layer.

14. The unitary optic member of claim 13 wherein the other layer is the innermost layer.

15. The unitary optic member of claim 11 wherein the layer forming the outermost layer and the non-lens portion is injection-molded.

16. The unitary optic member of claim 11 wherein the layer forming the outermost layer and the non-lens portion is thermoformed.

17. The unitary optic member of claim 11 wherein each of the lens portions further includes a third overmolded polymeric layer, the third polymeric layer being the innermost layer.

18. The unitary optic member of claim 17 wherein the third layer is an LSR layer.

19. The unitary optic member of claim 11 wherein the two layers have different indices of refraction.

20. The unitary optic member of claim 19 wherein the other layer is an LSR layer.

21. A method for manufacturing a unitary optic member having plural lens portions surrounded by and interconnected by a non-lens portion, the method comprising the steps of:

forming a first molded polymeric layer including the non-lens portion and an outermost layer of each of the lens portions, such forming step including forming a pocket-space at each lens portion; and

for each lens portion, injection-molding a second molded polymeric layer onto the first polymeric layer within the corresponding pocket-space.

22. The method of claim 21 wherein the first and second layers are of different polymeric materials.

23. The method of claim 22 wherein the first layer is an acrylic layer and the second layer is an LSR layer.

24. The method of claim 23 wherein the second layer is the innermost layer.

25. The method of claim 21 wherein the first molded polymeric layer is injection-molded.

26. The method of claim 21 wherein the first molded polymeric layer is thermoformed.

27. The method of claim 21 wherein each of the lens portions further includes a third molded polymeric layer overmolded onto the second polymeric layer within the corresponding pocket-space, the third molded polymeric layer being the innermost layer.

28. The method of claim 27 wherein the third layer is an LSR layer.

29. The method of claim 21 wherein the two layers have different indices of refraction.

30. The method of claim 29 wherein the second layer is an LSR layer.

31. In an LED light fixture including (a) a heat-sink structure having a mounting surface, (b) a circuit board on the mounting surface and having a plurality of LED light sources spaced thereon, and (c) an optic member over the circuit board and having a plurality of secondary lenses thereon each in alignment with a corresponding one of the light sources, the improvement wherein the optic member comprises:

a first molded polymeric layer forming (a) the non-lens portion and (b) an outermost layer of each of the lens portions, the outermost layer of each lens portion forming a pocket-space at such lens portion; and

for each lens portion, a second molded polymeric layer overmolded onto the first polymeric layer within the corresponding pocket-space.

32. The LED light fixture of claim 31 wherein the first and second layers are of different polymeric materials.

33. The LED light fixture of claim 32 wherein the first layer is an acrylic layer and the second layer is an LSR layer.

34. The LED light fixture of claim 33 wherein the second layer is the innermost layer.

35. The LED light fixture of claim 31 wherein the first molded polymeric layer is injection-molded.

36. The LED light fixture of claim 31 wherein the first molded polymeric layer is thermoformed.

37. The LED light fixture of claim 31 wherein each of the lens portions further includes a third molded polymeric layer overmolded onto the second polymeric layer within the corresponding pocket-space, the third molded polymeric layer being the innermost layer.

38. The LED light fixture of claim 37 wherein the third layer is an LSR layer.

39. The LED light fixture of claim 31 wherein the two layers have different indices of refraction.

40. The LED light fixture of claim 39 wherein the second layer is an LSR layer.

50. The multi-layer polymeric lens of claim 39 wherein another of the layers includes a flange extending beyond the lens optical footprint.

41. In a multi-layer polymeric lens for directing light from an LED light source, the lens comprising at least an innermost layer and an outermost layer and defining a lens optical footprint, the improvement wherein the innermost layer is less than coextensive with the lens optical footprint.

42. The multi-layer polymeric lens of claim 41 wherein the innermost and outermost layers are of an acrylic.

43. The multi-layer polymeric lens of claim 41 wherein the outermost layer includes a flange extending beyond the lens optical footprint.

44. The multi-layer polymeric lens of claim 41 wherein the two layers have different indices of refraction.

45. The multi-layer polymeric lens of claim 41 further including an intermediate layer between the innermost and outermost layers.

46. The multi-layer polymeric lens of claim 45 wherein the innermost, intermediate, and outermost layers are of an acrylic.

47. The multi-layer polymeric lens of claim 45 wherein the outermost layer includes a flange extending beyond the lens optical footprint.

48. The multi-layer polymeric lens of claim 45 wherein the two layers have different indices of refraction.

49. In a multi-layer polymeric lens for directing light from an LED light source, the lens defining a lens optical footprint, the improvement wherein at least one of the layers is less than coextensive with the lens optical footprint.