Optical filter for sunglasses
AssigneeSilhouette International Schmied AG
InventorsRupert Spindelbalker, Karin Toni Bigel, Jr., Marie-Christiane Nammour, Kévin Anh Quoc Le Quang
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Abstract
In an optical filter for sunglasses, having a transmittance of less than 20% for light wavelengths from 400 nm to 650 nm, the transmission spectrum comprises a local transmission maximum in each of the light wavelength ranges between 440 nm and 470 nm and also between 570 nm and 590 nm and a local transmission maximum in the light wavelength range between 600 nm and 620 nm, wherein the transmittance below the connecting line of the local transmission maximum between 440 nm and 470 nm and the local transmission maximum between 570 nm and 590 nm has an essentially convex overall curve with a breadth of variation less than 8%.
Claims17
An optical filter for sunglasses, having a transmittance of less than 20% for light wavelengths from 400 nm to 650 nm, wherein a transmission spectrum comprises a local transmission maximum in each of the light wavelength ranges between 440 nm and 470 nm and between 570 nm and 590 nm and a local transmission maximum or a transmission saddle point in the light wavelength range between 600 nm and 620 nm, wherein a transmittance below a connecting line of the local transmission maximum between 440 nm and 470 nm and the local transmission maximum between 570 nm and 590 nm has an essentially convex overall curve with a breadth of variation less than 8%.
An optical filter for sunglasses, having a transmittance of less than 20% for light wavelengths from 400 nm to 650 nm, wherein a transmission spectrum of the optical filter comprises:
- a first local transmission maximum in a light wavelength range between 440 nm and 470 nm;
- a second local transmission maximum in a light wavelength range between 570 nm and 590 nm;
- and
- a third local transmission maximum or a transmission saddle point in the light wavelength range between 600 nm and 620 nm,
- wherein a transmittance below a connecting line of the first local transmission maximum and the second local transmission maximum has an essentially convex overall curve.
A method of making an optical filter for sunglasses, the optical fiber having a transmittance of less than 20% for light wavelengths from 400 nm to 650 nm and a transmission spectrum of the optical filter having a first local transmission maximum in a light wavelength range between 440 nm and 470 nm, a second local transmission maximum in a light wavelength range between 570 nm and 590 nm and a third local transmission maximum or a transmission saddle point in the light wavelength range between 600 nm and 620 nm, the method comprising:
- forming a plastic matrix, including admixing pigments into a thermoplastic, the pigments including between 400 and 700 ppm of a UV filter pigment, between 33 and 98 ppm of a blue pigment, between 75 and 96 ppm of a yellow pigment, between 124 and 174 ppm of a red pigment, and between 37 and 115 ppm of a green pigment.
Dependencies are inferred from the claim text.