Optical waveguide body
View Patent ↗An optical waveguide body includes a first layer of optically transmissive material and a second layer of optically transmissive material in contact with the first layer. At least one of the first and second layers is tapered and the first layer has a first index of refraction and the second layer has a second index of refraction less than the first index of refraction and the first and second indices of refraction are both greater than about 1.0.
1. An optical waveguide body, comprising:
a first layer of optically transmissive material comprising a thickness defined by a first side and second side;
a second layer of optically transmissive material comprising a third side and a fourth side opposite the third side, said third side in contact with the second side of the first layer;
wherein the first layer has a first index of refraction and the second layer has a second index of refraction less than the first index of refraction and wherein the first and second indices of refraction are both greater than about 1.0; and
a body of material extending into the first layer from the first side and comprising an index of refraction greater than the first index of refraction, wherein the second layer comprises a plurality of ridges and grooves on the fourth side, wherein each of the ridges comprises a first height, wherein the body of material comprises a second height that is larger than the first height.
2. The optical waveguide body of claim 1 , wherein the second layer is discontinuous.
3. The optical waveguide body of claim 2 , wherein the second layer comprises linear facets.
4. The optical waveguide body of claim 2 , wherein the second layer comprises discrete facets.
5. The optical waveguide body of claim 1 , wherein the second layer is continuous and extends fully over the first layer.
6. The optical waveguide body of claim 1 , in combination with a light emitting diode (LED) that develops light which is transmitted into the waveguide body.
7. The optical waveguide body of claim 1 , wherein the first and second layers are tapered in opposite directions and are secured together in overlapping relationship.
8. The optical waveguide body of claim 1 , wherein the waveguide body has a substantially constant thickness throughout.
9. The optical waveguide body of claim 1 , further comprising a reflective layer disposed on the first side of the first layer opposite the second layer.
10. The optical waveguide body of claim 9 , wherein the reflective layer is a specular material.
11. The optical waveguide body of claim 9 , wherein the reflective layer is a white diffuse material.
12. The optical waveguide body of claim 1 , wherein an interface between the first and second layers is non-planar.
13. The optical waveguide body of claim 1 , wherein one of the first and second layers extends into another of the layers.
14. The optical waveguide body of claim 1 , wherein the first layer has an index of refraction that varies over the extent thereof.
15. The optical waveguide body of claim 1 , wherein at least one of the first and second layers is tapered.