LED device for wide beam generation

• US 9,388,949 B2
• Filed: 08/19/2013
• Issued: 07/12/2016
• Est. Priority Date: 02/27/2006
• Status: Active Grant

• Current Assignee: Signify Holding B.V. (Signify N.V.)
• Original Assignee: Illumination Management Solutions Incorporated (Eaton Corporation PLC.)
• Inventors: Holder, Ronald G., Rhoads, Greg
• Primary Examiner(s): Sember, Thomas M
• Application Number:
  US13/970,197
• Publication Number:
  US 20140049962A1
• Time in Patent Office: 1,058 Days
• US Class Current: 1/1
• CPC Class Codes: F21K 9/60 Optical arrangements integrated in the light source, e.g. for improving the colour rendering index or the light extraction
• CPC Class Codes: F21K 9/69 Details of refractors forming part of the light source
• CPC Class Codes: F21V 5/04 of lens shape
• CPC Class Codes: F21W 2131/103 of streets or roads
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: G02B 19/0028 refractive and reflective surfaces, e.g. non-imaging catadioptric systems
• CPC Class Codes: G02B 19/0061 the light source comprising a LED semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission H01L33/00
• CPC Class Codes: G02B 19/0071 adapted to illuminate a complete hemisphere or a plane extending 360 degrees around the source
• CPC Class Codes: H01L 33/58 Optical field-shaping elements
• CPC Class Codes: Y10T 29/49002 Electrical device making

Abstract

An apparatus and method is characterized by providing an optical transfer function between a predetermined illuminated surface pattern, such as a street light pattern, and a predetermined energy distribution pattern of a light source, such as that from an LED. A lens is formed having a shape defined by the optical transfer function. The optical transfer function is derived by generating an energy distribution pattern using the predetermined energy distribution pattern of the light source. Then the projection of the energy distribution pattern onto the illuminated surface is generated. The projection is then compared to the predetermined illuminated surface pattern to determine if it acceptably matches. The process continues reiteratively until an acceptable match is achieved. Alternatively, the lens shape is numerically or analytically determined by a functional relationship between the shape and the predetermined illuminated surface pattern and predetermined energy distribution pattern of a light source as inputs.

Claims

1. A light module comprising:

a substrate; and

a plurality of light sources disposed along the substrate, each light source comprising;

a respective lens; and

one or more respective light emitting diodes disposed adjacent the respective lens and having an axis projecting substantially perpendicularly away from the substrate and through the respective lens,

wherein the axis lies in a plane, and

wherein a portion of the respective lens disposed on a first side of the plane forms a prism that is laterally offset from the axis by a gap and that is operative to receive light from the one or more respective light emitting diodes and to direct the received light through the plane by reflection.

2. The light module of claim 1, wherein the prism comprises a totally internally reflective surface.

3. The light module of claim 1, wherein air is disposed in the gap.

4. The light module of claim 1, wherein directing the received light through the plane by reflection comprises directing the received light to pass through the plane outside the respective lens.

5. The light module of claim 1, wherein the plane is perpendicular to a second plane in which the axis also lies, and wherein the prism is symmetrical with respect to the second plane.

6. The light module of claim 1, wherein in addition to the prism, the respective lens comprises a surface divided into two subsurfaces by a centerline.

7. The light module of claim 1, wherein the axis is disposed at a right angle from the substrate.

8. A light module comprising:

a substrate; and

a plurality of light sources disposed along the substrate, each light source comprising;

a respective lens; and

a respective light emitting diode coupled to the respective lens and having an axis projecting in a perpendicular direction away from the substrate and through the respective lens,

wherein the axis lies in a plane, and

wherein a portion of the respective lens comprises a totally internally reflective surface that is disposed entirely on a first side of the plane and that is operative to receive light from the respective light emitting diode and to direct the received light through the plane by reflection.

9. The light module of claim 8, wherein the totally internally reflective surface is operative to form on the first side of the plane a beam that passes through the plane outside the respective lens, the beam comprising the received light.

10. The light module of claim 8, wherein the totally internally reflective surface is curved, and

wherein the respective lens further comprises a surface divided into two subsurfaces by a centerline.

11. The light module of claim 8, wherein an air gap is disposed between the totally internally reflective surface and the axis.

12. The light module of claim 8, wherein the light that is directed through the plane by reflection is configured to provide an illumination pattern that is biased street side relative to curb side.

13. A light module comprising:

a substrate; and

a plurality of light sources disposed along the substrate, each light source comprising;

a respective lens; and

a respective light emitting diode disposed between the respective lens and the substrate, the respective light emitting diode having an axis projecting perpendicularly away from the substrate and through the respective lens,

wherein the axis lies in a plane, and

wherein a portion of the respective lens is entirely disposed on a first side of the plane to operatively receive light from the respective light emitting diode and reflect said light to pass through the plane outside the lens.

14. The light module of claim 13, wherein the portion of the respective lens comprises a totally internally reflective surface, and

wherein an air gap is disposed between the totally internally reflective surface and the axis.

15. The light module of claim 13, wherein said portions of all the respective lenses disposed along the substrate are aligned to direct each said received light in a common direction.

16. The light module of claim 13, wherein the plurality of light sources disposed along the substrate form a two-dimensional array, and

wherein all of the planes are substantially parallel to one another, with all of the first sides facing in a common direction.

17. The light module of claim 13, wherein the two-dimensional array is operative to produce a two-dimensional illumination pattern on a surface that is perpendicular to the axis, and wherein the two-dimensional illumination pattern is symmetrical about a line on the surface running perpendicular to the plane.

18. The light module of claim 13, wherein the two-dimensional array is operative to produce a two-dimensional distribution of energy on a surface, and

wherein the two-dimensional distribution of energy is divisible into two substantially identical intensity patterns.

19. The light module of claim 13, wherein the two-dimensional array is operative to produce a two-dimensional distribution of energy on a surface, and

wherein a line on the surface bisects the two-dimensional distribution of energy into two intensity patterns that are substantially identical to one another with mirror image symmetry.

20. The light module of claim 13, wherein the portion of the respective lens is curved.