Color mixing optics for LED lighting

Abstract

Color mixing optics for a multi-color LED lamp comprise an outer reflector having a paraboloidal surface of revolution and a total inner reflection (TIR) lens having an outer contour with a paraboloidal surface of revolution. The outer reflector and the TIR lens are centered around a common center axis. A common focal point of the outer reflector and the TIR lens is provided for placing a LED assembly. Such LED lamps produce uniform color throughout the entire light beam while the outer dimensions are such that the optics fit into conventional lamp housings.

The invention claimed is: 
     
       1. A color mixing optics for LED lighting comprising:
 an outer reflector having a paraboloidal surface of revolution centered around a center axis and defining a reflector focal point; 
 a total inner reflection lens having a concave light entrance surface with a radius of curvature to enable light to enter the total inner reflection lens at a right angle, and the total inner reflection lens having an outer contour with a paraboloidal surface of revolution centered around the center axis and defining a total inner reflection lens focal point, wherein 
 the outer contour with a paraboloidal surface of revolution of the total inner reflection lens is held a spaced distance within the outer reflector; and 
 wherein the reflector focal point is in close proximity to the total inner reflection lens focal point; and 
 wherein a first portion of light emitted by a source positioned proximate the reflector focal point and the total inner reflection lens focal point is reflected by the outer reflector and the remaining portion of the light emitted by the source is received by the concave light entrance surface of the total inner reflection lens. 
 
     
     
       2. The color mixing optics according to  claim 1 , wherein the total inner reflection lens has a concave light entrance surface oriented towards the total inner reflection lens focal point. 
     
     
       3. The color mixing optics according to  claim 2 , wherein the concave light entrance surface has a spherical shape. 
     
     
       4. The color mixing optics according to  claim 1 , wherein the total inner reflection lens is positioned within the outer reflector. 
     
     
       5. The color mixing optics according to  claim 1 , wherein the total inner reflection lens is attached to a cover located on the outer reflector. 
     
     
       6. The color mixing optics according to  claim 1 , wherein the total inner reflection lens is part of a cover located on the outer reflector. 
     
     
       7. The color mixing optics of  claim 1 , wherein a radius of an upper aperture of the total inner reflection lens is substantially equal to a radius of a lower aperture of the outer reflector. 
     
     
       8. The color mixing optics of  claim 1 , wherein a depth of the total inner reflection lens extends to a point where the total inner reflection lens parabola intersects a line extending between a source point on the center axis and an edge point of the outer reflector. 
     
     
       9. A multi-color LED lamp comprising:
 an outer reflector having a paraboloidal surface of revolution centered around a center axis and defining a reflector focal point; 
 a total inner reflection lens having a concave light entrance surface with a radius of curvature to enable light to enter the total inner reflection lens at a right angle, and the total inner reflection lens having an outer contour with a paraboloidal surface of revolution centered around the center axis and defining a total inner reflection lens focal point; wherein the outer contour with a paraboloidal surface of revolution of the total inner reflection lens is held a spaced distance within the outer reflector; wherein the reflector focal point is in close proximity to the total inner reflection lens focal point; and an LED assembly comprising a plurality of LEDs and being mounted in close proximity to the reflector focal point and the total inner reflection lens focal point; 
 wherein the outer reflector reflects a first portion of light emitted by the LED assembly and the concave light entrance of the total inner reflection lens surface receives the remaining portion of the light emitted by the LED assembly. 
 
     
     
       10. The multi-color LED lamp according to  claim 9 , wherein the LED assembly or parts thereof are covered by a an LED lens. 
     
     
       11. The multi-color LED lamp according to  claim 10 , wherein the LED lens has a spherical shape. 
     
     
       12. The multi-color LED lamp according to  claim 9 , wherein the LED assembly has a an LED surface plane which is mounted in close proximity to the total inner reflection lens focal point. 
     
     
       13. The multi-color LED lamp according to  claim 9 , wherein the center of the LED assembly is mounted in close proximity to the center axis. 
     
     
       14. The multi-color LED lamp according to  claim 9 , wherein the LED assembly is mounted on a base. 
     
     
       15. The multi-color LED lamp according to  claim 9 , wherein a housing is provided surrounding the outer reflector. 
     
     
       16. The multi-color LED lamp according to claim  9  15, wherein the total inner reflection lens is attached to a cover located on the housing. 
     
     
       17. The multi-color LED lamp according to claim  9  15, wherein the total inner reflection lens is part of a cover located on the housing. 
     
     
       18. A method for generating a mixed beam of light by comprising: 
 generating light at multiple wavelengths by a an LED assembly comprising a plurality of LEDs and: 
 reflecting a first portion of said light by an outer reflector having a paraboloidal surface of revolution centered around a center axis and defining a reflector focal point; 
 while reflecting a secondreceiving the remaining portion of said light forwarded from the plurality of LEDsat a concave light entrance surface of a total inner reflection lens, the remaining portion of said light incident on the concave light entrance surface at an angle relative to the center axis that is less than the first portion of said lightforwarded from the plurality of LEDs, wherein the second portion is reflected from a total inner reflection lens having a concave light entrance surface with includes a surface having a radius of curvature to enable the remaining portion of the light to enter the total inner reflection lens at a right angle, and the total inner reflection lens having an outer contour with a paraboloidal surface of revolution centered around the center axis and defining a total inner reflection lens focal point; and 
 wherein the reflector focal point is in close proximity to the total inner reflection lens focal point. 
 
     
     
       19. The method as recited in  claim 18 , wherein said reflecting consists of avoiding any refraction. 
     
     
       20. The color mixing optics according to claim 1, further comprising a hemispherical lens disposed proximate a plurality of light emitting diode light sources, the hemispherical lens having a convex surface spaced apart from the concave light entrance surface of the paraboloidal total inner reflection lens and spaced apart from the outer reflector.  
     
     
       21. The multi-color LED lamp according to claim 9, further comprising a hemispherical lens disposed proximate a plurality of light emitting diode light sources, the hemispherical lens having a convex surface spaced apart from the concave light entrance surface of the paraboloidal total inner reflection lens.  
     
     
       22. An optic system comprising:
 an outer reflector to reflect a first portion of light emitted by a light source; and   a total inner reflection lens having a concave light entrance surface to receive the remaining portion of the light emitted by the light source, the concave light entrance surface having a radius of curvature to enable the light to enter the total inner reflection lens at a right angle, the total inner reflection lens further having an outer contour, wherein the outer contour of the total inner reflection lens is held a spaced distance within the outer reflector.    
     
     
       23. The optic system of claim 22,
 wherein the outer reflector has a paraboloidal surface of revolution, and   wherein the outer contour of the total inner reflection lens has a paraboloidal surface of revolution.    
     
     
       24. The optic system of claim 23,
 wherein the paraboloidal surface of revolution of the outer reflector is centered around a center of revolution;   wherein the paraboloidal surface of revolution of the outer contour of the total inner reflection lens is centered around the center of revolution; and   wherein the concave light entrance surface of the total inner reflection lens is centered around the center of revolution.    
     
     
       25. The optic system of claim 24, wherein a depth of the total inner reflection lens extends to a point that intersects a line that extends between a source point on the center axis and an edge point of the outer reflector.  
     
     
       26. The optic system of claim 22, wherein the total inner reflection lens is positioned within the outer reflector.  
     
     
       27. The optic system of claim 22, wherein the total inner reflection lens is integral with a cover located on the outer reflector.  
     
     
       28. The optic system according to claim 22, further comprising a hemispherical lens disposed proximate a plurality of light emitting diode light sources, the hemispherical lens having a convex surface spaced apart from the concave light entrance surface of the total inner reflection lens.  
     
     
       29. A lamp comprising:
 a hollow outer reflector to provide a reflective surface;   a total inner reflection lens having a concave light entrance surface with a radius of curvature to enable light to enter the total inner reflection lens at a right angle, the total inner reflection lens further having an outer contour, wherein the outer contour is held a spaced distance apart from the reflective surface provided by the hollow outer reflector; and   an assembly configured to emit light, wherein the assembly is mounted within the lamp spaced apart from the concave light entrance surface of the total inner reflection lens;   wherein the reflective surface reflects a first portion of light emitted by the assembly and the concave light entrance surface of the total inner reflection lens receives the remaining portion of the light emitted by the assembly.    
     
     
       30. The lamp of claim 29, wherein the assembly further comprises a sensor configured to measure light emitted by the assembly.  
     
     
       31. The lamp of claim 30, wherein the assembly further comprises a plurality of LEDs.  
     
     
       32. The lamp of claim 29,
 wherein the outer reflector has a paraboloidal surface of revolution; and   wherein the outer contour of the total inner reflection lens has a paraboloidal surface of revolution.    
     
     
       33. The lamp of claim 32,
 wherein the paraboloidal surface of revolution of the outer reflector is centered around a center of revolution;   wherein the paraboloidal surface of revolution of the outer contour of the total inner reflection lens is centered around the center of revolution; and   wherein the concave light entrance surface of the total inner reflection lens is centered around the center of revolution.    
     
     
       34. The lamp of claim 33, wherein a depth of the total inner reflection lens extends to a point that intersects a line that extends between a source point on the center axis and an edge point of the outer reflector.  
     
     
       35. The lamp of claim 29, wherein the total inner reflection lens is positioned within the outer reflector.  
     
     
       36. The lamp of claim 29, wherein the total inner reflection lens is integral with a cover located on the outer reflector.  
     
     
       37. A lamp, comprising:
 a hemispherical lens to receive an array that includes a plurality of different color output light sources;   a parabolic reflective surface spaced apart from the surface of the hemispherical lens; and   a paraboloidal total inner reflection lens spaced a distance from the parabolic reflective surface, the total inner reflection lens including a planar exit surface and a concave entrance surface spaced a distance apart from the surface of the hemispherical lens;   wherein the hemispherical lens comprises a planar base portion and a convex lens portion;   wherein the parabolic reflective surface and the paraboloidal total inner reflection lens share a common focal point; and   wherein the base portion of the hemispherical lens is positioned proximate the common focal point of the parabolic reflective surface and the paraboloidal total inner reflection lens.    
     
     
       38. The lamp of claim 37 wherein the hemispherical lens, the parabolic reflective surface, and the paraboloidal total inner reflection lens are positioned such that a first portion of light emitted by a light source disposed proximate the hemispherical lens falls incident on the parabolic reflective surface and the remaining portion of the light emitted by the light source passes through the paraboloidal total inner reflection lens.