Rugate lens for glasses
View Patent ↗An improved multi-layer performance lens for protective eyewear such as sunglasses which includes a pass band Rugate filter. The lens design is a sandwich configuration including a polarizing layer between two ophthalmic lens layers in a sandwich configuration, and a Rugate filter applied to one side thereof to yield an exceptional light transmission profile under all light conditions, thereby maximizing protection as well as clarity of vision. In addition, an optional dielectric layer and/or hydrophobic overcoat may be applied. The foregoing layers are arranged to provide a balanced light transmission profile optimum for preventing macular degeneration, cataracts and other ocular injuries.
1. A lens for protective eyewear to preserve ocular health, comprising:
a first ophthalmic lens layer;
a second ophthalmic lens layer;
a polarizing layer sandwiched between said first and second ophthalmic lens layers; and
a Rugate filter layer defining a pass band filter with cutoffs at approximately 400 nanometers (nm) and 780 nm, said rugate filter being applied exteriorly to one of said first and second ophthalmic lens layers;
whereby said layers combine to provide a balanced light transmission profile in which substantially 100% of UV-A & B light below 400 nm is reflected, and substantially 100% of near infrared light above 680 nm is reflected.
2. The lens for protective eyewear to preserve ocular health according to claim 1 , wherein said Rugate filter layer further comprises a multi-layered Rugate filter.
3. The lens for protective eyewear to preserve ocular health according to claim 2 , wherein said multi-layered Rugate filter comprises a first Rugate layer for reflecting light below 400 nm, and a second Rugate layer for reflecting light above 680 nm.
4. The lens for protective eyewear to preserve ocular health according to claim 1 , wherein said polarizing layer is encapsulated between two optical lens layers.
5. The lens for protective eyewear according to claim 1 , wherein said first ophthalmic lens layer and second ophthalmic lens layer are any one from among the group consisting of glass, plastic (CR-39), polycarbonate, Trivex® and high-index plastic or glass.
6. The lens for protective eyewear according to claim 1 , further comprising a dielectric minor in advance of said rugate filter layer for supplementing the rugate filter in reducing glare and overall light transmission.
7. The lens for protective eyewear according to claim 1 , further comprising a hydrophobic overcoat over said rugate filter and lens sandwich.
8. The lens for protective eyewear according to claim 6 , further comprising a hydrophobic overcoat over said dielectric mirror.
9. The lens for protective eyewear according to claim 1 , wherein said first lens layer and second lens layer are colorized with one from among the group of high-contrast blue-blocking amber-tint and color discriminating grey tint.
10. The lens for protective eyewear according to claim 8 , wherein said dielectric minor further comprises a multi-layered dielectric mirror.
11. A sunglass lens comprising rugate filter means for selectively filtering wavelengths of light to preserve macular integrity.
12. A sunglass lens, comprising:
a polarizing film layer sandwiched between first and second ophthalmic lens layers;
a rugate filter applied to one of said first and second ophthalmic lens layers, said rugate filter being formed as a transparent coating with an incrementally varying refractive index profile along its width;
a dielectric mirror for supplementing the rugate filter in reducing glare and overall light transmission;
whereby said polarizing layer, rugate filter, and first and second ophthalmic lens layers are arranged to provide a balanced light transmission profile in which substantially 100% of UV-A & B light is absorbed to at least 400 nm.
13. The sunglass lens according to claim 12 , further comprising a hydrophobic overcoat on said dielectric mirror layer.