摘要:
A process is described for manufacturing an ophthalmic lens containing a Fresnel microstructured surface inside the lens. The Fresnel lens is injection molded with a mold insert having a heat conductivity lower than the thermoplastic material used to form the Fresnel lens. A second thermoplastic material is overmolded to the Fresnel lens to cover and protect the microstructured surface. The mold insert is made from nickel or a thermoplastic material. The resulting lens includes two layers having different refractive indices. The Fresnel lens may be made from polycarbonate while the overmold may be made from a poly(methyl methacrylate) or a thermoplastic polyurethane.
摘要:
A process for manufacturing an ophthalmic lens containing a Fresnel microstructured surface inside the lens. The Fresnel lens is injection molded with a mold insert having a heat conductivity lower than the thermoplastic material used to form the Fresnel lens. A second thermoplastic material is overmolded to the Fresnel lens to cover and protect the microstructured surface. The mold insert is made from Nickel or thermoplastic. The resulting lens includes two layers having different refractive indices. The Fresnel lens is made from polycarbonate while the overmold is made from PMMA or TPU.
摘要:
A method and apparatus for elimination of lamination defects on progressive addition lenses. The lamination method uses a flexible bladder designed to apply pressure evenly across the lens surface. A spacer is positioned between a Hard Multi-Coat carrier and the flexible bladder. The spacer is located in a region of the carrier which is designated to deliver a coating to a section of the lens which is farthest from the carrier. The spacer asymmetrically increases the pressure applied to the carrier to eliminate lamination defects.
摘要:
A method and apparatus for elimination of lamination defects on progressive addition lenses. The lamination method uses a flexible bladder designed to apply pressure evenly across the lens surface. A spacer is positioned between a Hard Multi-Coat carrier and the flexible bladder. The spacer is located in a region of the carrier which is designated to deliver a coating to a section of the lens which is farthest from the carrier. The spacer asymmetrically increases the pressure applied to the carrier to eliminate lamination defects.