TOTAL INTERNAL REFLECTION LENS FOR COLOR MIXING

• US 20100091491A1
• Filed: 10/12/2009
• Published: 04/15/2010
• Est. Priority Date: 10/14/2008
• Status: Active Grant

• Current Assignee: Ledengin, Inc. (Ams-Osram AG)
• Original Assignee: Ledengin, Inc. (Ams-Osram AG)
• Inventors: Mei, Zequn, Jiang, Wu, Yan, Xiantao
• Granted Patent: US 8,430,537 B2
• Time in Patent Office: Days
• US Class Current: 362/235
• CPC Class Codes: F21K 9/64 using wavelength conversion means distinct or spaced from the light-generating element, e.g. a remote phosphor layer
• CPC Class Codes: F21V 5/04 of lens shape
• CPC Class Codes: F21Y 2113/17 forming a single encapsulated light source
• 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 19/0066 in the form of an LED array
• CPC Class Codes: H01L 33/58 Optical field-shaping elements

Abstract

A total-internal-reflection (TIR) lens for color mixing includes a body member having an outer surface and an interior open channel extending longitudinally through the body member. The body member and the interior open channel are substantially symmetric with respect to an optical axis, and the outer surface is shaped to provide total internal reflection. The body member has a first end surface region at a first end of the open channel for accommodating a light source and a second end surface region opposite the first end region. The second end surface region includes a plurality of refractive surface regions positioned around the second end region of the open channel. The lens is configured to provide projected light substantially centered with respect to the optical axis when the light source is positioned off the optical axis. In a specific embodiment, a lighting apparatus for providing centered white light includes such a lens and a plurality of light sources.

Claims

1. A lens, comprising:

a body member having an outer surface and an interior open channel extending longitudinally through the body member, the body member and the interior open channel being substantially symmetric with respect to an optical axis, the outer surface being shaped to provide total internal reflection,

the body member having a first end surface region at a first end region of the open channel for accommodating a light source and a second end surface region opposite the first end surface region and surrounding a second end region of the open channel, the second end surface region including a plurality of refractive surface regions positioned around the second end region of the open channel,

wherein the lens is configured to provide projected light substantially centered with respected to the optical axis when the light source is positioned off the optical axis.

2. The lens of claim 1 wherein the interior open channel is characterized by a substantially cylindrical sidewall.

3. The lens of claim 1 wherein a side wall of the interior open channel extends from the first end region to the second end region of the interior open channel substantially without bending.

4. The lens of claim 1 wherein a side wall of the interior open channel forms angle of approximately 1 degree with respect to the optical axis.

5. The lens of claim 1 wherein the multiple refractive surface regions comprise hexagonal shaped regions in a honeycomb arrangement.

6. The lens of claim 1 wherein the light source comprises a light-emitting diode (LED).

7. The lens of claim 1 wherein the light source comprises a light-emitting diode (LED), a matrix material having a first refractive index overlying the LED, and a dispersion of beads within the matrix material, the beads having a second refractive index different than the first refractive index.

8. The lens of claim 1 wherein the light source comprises four light-emitting-diodes.

9. The lens of claim 1 wherein the light source comprises a red LED, a green LED, a blue LED, and an amber LED, and wherein the lens is configured to provide substantially centered white light.

10. A lighting apparatus, comprising:

a light source; and

a lens disposed adjacent to the light source,

wherein the lens has an optical axis and is configured to provide projected light substantially centered with respect to the optical axis when the light source is positioned off the optical axis.

11. The lighting apparatus of claim 10 wherein the lens further comprising:

a body member having an outer surface and an interior open channel extending longitudinally through the body member, the body member and the interior open channel being substantially symmetric with respect to an optical axis, the outer surface being shaped to provide total internal reflection,

the body member having a first end surface region at a first end region of the open channel for accommodating a light source and a second end surface region opposite the first end surface region and surrounding a second end region of the open channel, the second end surface region having a plurality of refractive surface regions positioned around second end region of the open channel.

12. The lighting apparatus of claim 10 wherein the interior open channel is characterized by a substantially cylindrical sidewall.

13. The lighting apparatus of claim 10 wherein a side wall of the interior open channel extends from the first end region to the second end region of the interior open channel substantially without bending.

14. The lighting apparatus of claim 10 wherein a side wall of the interior open channel forms angle of approximately 1 degree with respect to the optical axis.

15. The lighting apparatus of claim 10 wherein the light source comprises a light-emitting diode (LED).

16. The lighting apparatus of claim 10 wherein the light source comprises a light-emitting diode (LED), a matrix material having a first refractive index overlying the LED, and a dispersion of beads within the matrix material, the beads having a second refractive index different than the first refractive index.

17. The lighting apparatus of claim 10 wherein the light source comprises four light-emitting-diodes.

18. The lighting apparatus of claim 10 wherein the light source comprises a red LED, a green LED, a blue LED, and an amber LED, and wherein the lens is configured to provide substantially centered white light.

19. A lighting apparatus, comprising:

a light source, the light source including at least one light-emitting diode (LED), a matrix material having a first refractive index overlying the at least one LED, and a dispersion of beads within the matrix material, the beads having a second refractive index different than the first refractive index; and

a lens having a body member that includes an outer surface and an interior open channel extending longitudinally through the body member, the body member and the interior open channel being substantially symmetric with respect the an optical axis, the outer surface being shaped to provide total internal reflection,

wherein the lens is configured to provide projected light substantially centered with respect to the optical axis when the light source is positioned off the optical axis.

20. The lighting apparatus of claim 19 wherein the interior open channel is characterized by a substantially cylindrical sidewall.

21. The lighting apparatus of claim 19 wherein a side wall of the interior open channel extends from the first end region to the second end region of the interior open channel substantially without bending, wherein the interior open channel is characterized by a substantially cylindrical sidewall.

22. The lens of claim 19 wherein a side wall of the interior open channel forms angle of approximately 1 degree with respect to the optical axis.

23. The lighting apparatus of claim 19 wherein the light source comprises a red LED, a green LED, a blue LED, and an amber LED, and wherein the lens is configured to provide substantially centered white light.