LED LENS

• US 20100177532A1
• Filed: 01/14/2010
• Published: 07/15/2010
• Est. Priority Date: 01/15/2009
• Status: Active Grant

• Current Assignee: Ilumisys Incorporated (Altair Engineering Incorporated)
• Original Assignee: Altair Engineering Incorporated
• Inventors: Lavering, Gordon R., Ivey, John, Simon, David L.
• Granted Patent: US 8,556,452 B2
• Time in Patent Office: Days
• US Class Current: 362/555
• CPC Class Codes: B29D 11/00278 Lenticular sheets B29D11/00269 takes precedence
• CPC Class Codes: F21K 9/27 Retrofit light sources for lighting devices with two fittings for each light source, e.g. for substitution of fluorescent tubes
• CPC Class Codes: F21K 9/68 Details of reflectors forming part of the light source
• CPC Class Codes: F21K 9/69 Details of refractors forming part of the light source
• CPC Class Codes: F21V 5/048 the lens being a simple lens adapted to cooperate with a point-like source for emitting mainly in one direction and having an axis coincident with the main light transmission direction, e.g. convergent or divergent lenses, plano-concave or plano-convex lenses
• CPC Class Codes: F21V 7/0083 Array of reflectors for a cluster of light sources, e.g. arrangement of multiple light sources in one plane combination of two or more reflectors F21V7/0025
• CPC Class Codes: F21V 7/0091 using total internal reflection
• CPC Class Codes: F21V 7/041 with conical or pyramidal surface
• CPC Class Codes: F21Y 2103/10 comprising a linear array of point-like light-generating elements
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H01L 2924/00012 Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• CPC Class Codes: H01L 2924/181 Encapsulation
• CPC Class Codes: H01L 2924/1815 Shape
• CPC Class Codes: H01L 33/54 having a particular shape

Abstract

A light modifier for an LED producing light about a central axis is provided. The light modifier includes a lens defining an indentation. The indentation is angled relative to the central axis by an amount less than a complementary angle of a critical angle of the lens along the indentation. The lens can reduce the appearance of a bright spot created by the LED.

Claims

1. A light modifier for an LED producing light about a central axis, the light modifier comprising:

a lens defining an indentation, the indentation angled relative to the central axis by an amount less than a complementary angle of a critical angle of the lens along the indentation.

2. The light modifier of claim 1, wherein the indentation is angled between approximately 15 and 25 degrees relative to the central axis.

3. The light modifier of claim 2, wherein the indentation is angled approximately 20 degrees relative to the central axis.

4. The light modifier of claim 2, wherein the entire indentation is angled a same degree relative to the central axis.

5. The light modifier of claim 1, wherein a width of the indentation is at least as large as a diameter of a bright spot produced by the LED.

6. The light modifier of claim 1, wherein a surface of the indentation is substantially smooth.

7. The light modifier of claim 1, wherein the indentation is one of conical and V-shaped.

8. The light modifier of claim 1, wherein the lens includes a light diffuser around the indentation.

9. The light modifier of claim 1, wherein a portion of the lens circumscribing the indentation is hemispherical.

10. The light modifier of claim 1, further comprising a reflector within the indentation.

11. The light modifier of claim 1, wherein an outer surface of the lens outwardly extends from an edge of the indentation to a base wall.

12. The light modifier of claim 1, wherein the outer surface is angled relative to a horizontal axis approximately between 70 and 80 degrees.

13. A replacement light for a fluorescent tube usable in a fluorescent fixture comprising:

a support structure having a longitudinal axis;

at least one LED connected to the support structure, the LED producing light about respective central axes;

at least one lens positioned along the central axis of the at least one LED, the lens defining an indentation angled relative to the central axis less than a complementary angle of a critical angle of the lens along the indentation; and

at least one electrical connector at a longitudinal end of the support structure in electrical communication with the at least one LED.

14. The replacement light of claim 13, wherein the lens includes multiple indentations, each indentation positioned along the central axis of one of the at least one LEDs.

15. The replacement light of claim 14, wherein the lens is hemispherically shaped around each indentation.

16. The replacement light of claim 14, wherein the indentations are conically shaped.

17. The replacement light of claim 14, wherein the lens includes integral Fresnel lenses between indentations.

18. The replacement light of claim 13, wherein the lens includes a single V-shaped indentation extending longitudinally a length of the lens.

19. The replacement light of claim 13, wherein the indentation is angled between approximately 15 and 25 degrees relative to the central axis.

20. The replacement light of claim 19, wherein the entire indentation is angled approximately 20 degrees relative to the axis.

21. The replacement light of claim 13, wherein a width of the indentation is greater than a diameter of a bright spot produced by the at least one LED.

22. The replacement light of claim 13, wherein the lens includes a light pipe around each indentation.

23. The replacement light of claim 22, wherein the light pipe includes a light diffuser on at least one of a top surface and a bottom surface thereof.

24. The replacement light of claim 22, wherein the light diffuser is more densely disbursed on at least one of the distal ends of the light pipe.

25. The replacement light of claim 22, wherein the at least one LED includes multiple LEDs and the light pipe is positioned over substantially all of the multiple LEDs.

26. The replacement light of claim 22, wherein the light pipe tapers from the indentation toward at least one of the distal ends of the light pipe.

27. The replacement light of claim 13, wherein the lens includes a double-coned shaped outer wall surface.

28. The replacement light of claim 13, wherein an outer surface of the lens outwardly extends from an edge of the indentation to a base wall.

29. The light modifier of claim 13, wherein the outer surface is angled relative to a horizontal axis approximately between 70 and 80 degrees.

30. A method of forming a lens for an LED producing light about a central axis, the lens defining an indentation angled relative to the central axis less than a complementary angle of a critical angle of the lens along the indentation, the method comprising:

extruding material in an extrusion direction to form a sheet of greater width than the lens, the sheet having a same profile as the lens; and

sectioning the sheet to form the lens.

31. The method of claim 30, wherein sectioning the sheet including cutting the sheet perpendicular to the extruding direction.

32. A replacement light for a fluorescent tube usable in a fluorescent fixture comprising:

a support structure having a longitudinal axis;

multiple LEDs connected to the support structure, the LEDs producing light about respective central axes;

at least one light pipe positioned along the central axis of one of the LEDs, the light pipe having a reflector positioned over at least a portion of the LED such that the light initially emitted from the LED strikes the reflector; and

at least one electrical connector at a longitudinal end of the support structure in electrical communication with the multiple LEDs.