Crazing resistant coating and method thereof
View Patent ↗An anti-reflective coating system configured to resist crazing resulting from applied compressive forces, and an optical article employing the anti-reflective coating system; and methods of forming the same.
1. An optical article having anti-reflective properties comprising:
a bulk material having a first and a second optical surface;
a first anti-reflective coating formed of a plurality of layers of a high, mid, and/or low refractive index material applied over the first optical surface;
a second anti-reflective coating formed of a plurality of layers of a high, mid, and/or low refractive index material applied over the second optical surface, a total number of layers of the plurality of layers of the high, mid, and/or low refractive index material of the second anti-reflective coating greater than a total number of layers of the plurality of layers of the high, mid, and/or low refractive index material of the first anti-reflective coating; and
a reflection spectrum of the second anti-reflective coating substantially the same as a reflection spectrum of the first anti-reflective coating and a mechanical property of the second anti-reflective coating distinct from a mechanical property of the first anti-reflective coating.
2. The optical article of claim 1 wherein the bulk material is a cast lens or an injection molded lens.
3. The optical article of claim 1 wherein the bulk material comprises an optically functional laminate.
4. The optical article of claim 1 wherein the first optical surface is convex.
5. The optical article of claim 1 wherein the second optical surface is concave.
6. The optical article of claim 1 wherein the plurality of layers of the first anti-reflective coating comprises a total of four layers.
7. The optical article of claim 1 wherein the plurality of layers of the first anti-reflective coating comprises at least one layer formed of a high refractive index material having a thickness greater than approximately 100 nanometers.
8. The optical article of claim 1 wherein the plurality of layers of the second anti-reflective coating comprises a total of six layers.
9. The optical article of claim 1 further comprising a hard-coating applied directly on the first and the second optical surface.
10. The optical article of claim 1 wherein the second anti-reflective coating substantially resists crazing when the second optical surface is exposed to a change in diopter of greater than 5 diopter due to a compressive force applied to the optical surface.
11. The optical article of claim 1 further comprising a UV cured hard-coating applied directly on the second optical surface.
12. The optical article of claim 1 wherein the first anti-reflective coating comprises a Bayer abrasion resistance greater than 1.5.