Index matching layers
Optical devices such as eyeglass lenses and digital displays having improved optical characteristics achieved, in part, through incorporation of an index matching system between material layers having different refractive indices.
1. An eyeglass lens having reduced interference fringes comprising:
a base lens substrate having a first refractive index;
an index matching system disposed on a surface of the base lens substrate and having a plurality of index matching layers; and
a coating disposed on a surface of the index matching system having a second refractive index that differs from the first refractive index by 0.08 or greater;
wherein a single surface peak-to-peak reflectance variation across the visible spectrum of the optical device is below 2%.
2. The eyeglass lens of claim 1 wherein the plurality of index matching layers comprises either a first layer stack or a second layer stack;
the first layer stack comprising the following layers: 15.9 nm of SiO2, 33.7 nm of Y2O3, 41.5 nm of SiO2, 26.0 nm of Y2O3, 53.4 nm of SiO2, 9.9 nm of Y2O3, and 8.0 nm of SiO2;
the second layer stack comprising the following layers: 12.6 nm of SiO2, 47.9 nm of SiOxNy, 35.1 nm of SiO2, 32.0 nm of SiOxNy, 48.0 nm of SiO2, 11.2 nm of SiOxNy, and 2.0 nm of SiO2.
3. The eyeglass lens of claim 1 wherein the base lens substrate comprises a functional film laminate.
4. The eyeglass lens of claim 1 wherein the base lens substrate comprises a photochromic property.
5. The eyeglass lens of claim 1 wherein the index matching system is disposed on a back surface of the base lens substrate.
6. The eyeglass lens of claim 1 wherein the index matching system comprises a series of layers of materials wherein immediately adjacent layers of materials have distinct refractive indices relative to one another.
7. The eyeglass lens of claim 1 wherein the index matching system comprises a series of alternating urethane-based layers having different refractive indices.
8. The eyeglass lens of claim 1 wherein the coating is a UV cured hard-coating.
9. The eyeglass lens of claim 1 wherein the first refractive index is equal to or greater than 1.60 and the second refractive index is approximately 1.50.
10. The eyeglass lens of claim 1 further comprising an antireflective system disposed on the coating.
11. The eyeglass lens of claim 1 wherein the single surface peak-to-peak reflectance variation is the absolute difference in reflection between adjacent peaks and valleys across the visible spectrum of the lens.
12. A system for improving optical characteristics in optical devices comprising:
a first material layer having a first refractive index;
a second material layer having a second refractive index different from the first refractive index; and
an index matching system interposed between the first material layer and the second material layer that attenuates a total reflectance of incident light of the optical device;
wherein a single surface average peak-to-peak reflectance variation across the visible spectrum of only the first material layer, the second material layer, and the index matching system is below 2%.
13. The system of claim 12 wherein the optical device is an eyeglass lens.
14. The system of claim 12 wherein the single surface peak-to-peak reflectance variation is the absolute difference in reflection between adjacent peaks and valleys across the visible spectrum of the lens.
15. The system of claim 12 wherein the index matching system comprising either a first layer stack or a second layer stack;
the first layer stack comprising the following layers: 15.9 nm of SiO2, 33.7 nm of Y2O3, 41.5 nm of SiO2, 26.0 nm of Y2O3, 53.4 nm of SiO2, 9.9 nm of Y2O3, and 8.0 nm of SiO2;
the second layer stack comprising the following layers: 12.6 nm of SiO2, 47.9 nm of SiOxNy, 35.1 nm of SiO2, 32.0 nm of SiOxNy, 48.0 nm of SiO2, 11.2 nm of SiOxNy, and 2.0 nm of SiO2.
16. A method for reducing interference fringes observed in an optical article comprising:
obtaining a base lens substrate having a first refractive index;
forming an index matching system on a surface of the base lens substrate having a plurality of material layers; and
applying a coating on a surface of the index matching system having a second refractive index that differs from the first refractive index by 0.08 or greater;
wherein a single surface average peak-to-peak reflectance variation across the visible spectrum of only the base lens, the index matching system, and the hard coating is below 2%.
17. The method of claim 16 wherein obtaining the base lens substrate having the first refractive index comprises obtaining an eyeglass lens.
18. The method of claim 16 wherein the single surface peak-to-peak reflectance variation is the absolute difference in reflection between adjacent peaks and valleys across the visible spectrum of the lens.
19. The method of claim 16 wherein the index matching system comprises either a first layer stack or a second layer stack;
the first layer stack comprising the following layers: 15.9 nm of SiO2, 33.7 nm of Y2O3, 41.5 nm of SiO2, 26.0 nm of Y2O3, 53.4 nm of SiO2, 9.9 nm of Y 2 O 3 , and 8.0 nm of SiO2;
the second layer stack comprising the following layers: 12.6 nm of SiO2, 47.9 nm of SiOxNy, 35.1 nm of SiO2, 32.0 nm of SiOxNy, 48.0 nm of SiO2, 11.2 nm of SiOxNy, and 2.0 nm of SiO2.