Abstract: The present invention relates to novel ophthalmic lens elements and eyewear having wide field of view, low distortion, improved astigmatism correction where required and enhanced eye protection properties. Series of lens elements have steeply curved spherical reference surfaces. The edged lenses of the series have approximately consistent aperture size, shape and hollow depth across a range of common prescriptions.

Abstract: A cross-linkable polymeric casting composition including an effective amount ofA: an acrylic or methacrylic monomer which provides high rigidity and low colour dispersion (High Abbe number) to the final product;B: a di- or polythio compound;C: a di- or polyvinyl monomer; and optionallyD: a polymerisable comonomer.

Abstract: A light-transmissible article formed from a polymeric material, which article includes at least one photochromic dye; and a compatible light absorbing material distributed on or within the article; the combination of photochromic dye and compatible light absorbing material is such that the depth of darkening upon activation of photochromic dye is rendered substantially uniform regardless of variations in length, thickness or local changes of surface shape.

Abstract: A process for preparing a cross-linked polymeric article, which process includes: providing a cross-linkable polymeric casting composition; and a photochromic composition; subjecting the cross-linkable polymeric casting composition to partial cure, such that the polymer reaches or exceeds its point of gelation; contacting the partially cured gelled polymer with the photochromic composition; and curing the gelled polymer.

Abstract: Disclosed is a lens wafer suitable for use in preparing a laminated lens which wafer has a coating on at least one surface thereof in the form of a peelable protective film.

Abstract: A progressive ophthalmic lens including a lens surface having: a lower viewing zone providing good optical quality at a predetermined high surface power over a large area of vision; said predetermined power being determined by the viewer's near prescription (R.sub.x) the horizontal fitting position normally being determined by the near pupillary distance of the wearer, and the vertical fitting position normally being determined by the vertical frame midpoint, an upper viewing zone of lower surface power providing an enhanced range of vision for intermediate or greater viewing distances; and a corridor of relatively low astigmatism extending therebetween; wherein the contours of mean surface power and/or surface astigmatism within the lower viewing zone, upper viewing zone and corridor are generally symmetric about a vertical lens meridian as fitted to the wearer.

Abstract: A series of progressive ophthalmic lens elements, each lens element including a lens surface havingan upper viewing zone having a surface power to achieve a refracting power corresponding to distance vision;a lower viewing zone having a greater surface power than the upper viewing zone to achieve a refracting power corresponding to near vision;a corridor of relatively low surface astigmatism connecting the upper and lower zones, said corridor having a surface power varying from that of the upper viewing zone to that of the lower viewing zone;the progressive ophthalmic tens series includinga first set of lens elements having a base curve(s) suitable for use in providing a range of distance prescriptions for a first category of patient; anda second set of lens elements having a base curve(s) suitable for use in providing a range of distance prescriptions for a second category of patient; each lens element within a set differing in prescribed addition power and including a progressive design, in at least one of

Abstract: A button for forming a segment of a multifocal lens the button comprising a first portion composed of a lead oxide-containing glass, a second portion composed of a glass which contains substantially no lead oxide, the first and second portions being adjacent and forming a face of button for machining to a desired shape, and a third portion composed of a glass which contains substantially no lead oxide, the first and second glass portions being fused the third glass portion on a side of the first and second portions remote from the said face of the button.

Abstract: A cross-linkable polymeric casting composition includinga fluorene diacrylate or dimethacrylate monomer; anda comonomer including a polymerisable double bond.

Abstract: A cross-linkable polymeric casting composition including at least polyoxyalkylene glycol diacrylate or dimethacrylate and at least one polyfunctional unsaturated cross-linking agent. The casting composition may be utilized in the manufacture of plastic optical articles such as video discs and ophthalmic lenses.

Abstract: A method for optimizing the performance of an ophthalmic progressive lens having a distance viewing zone, a near viewing zone, and an intermediate zone, and the resulting optimized lens are provided. The surface of the lens to be optimized, which has at least one quantitative performance characteristic, is represented by a mathematical base function which is com=bined with a selected optimization function. The optimization function includes at least one adjustable parameter and may have at least one boundary condition imposed on it along the boundary of a selected subregion of the lens surface. A quantitative merit figure of the combination of the base and optimization functions, which is related to the at least one performance characteristic by a selected merit function, is optimized through the at least one adjustable parameter of the optimization function. Through the optimization, there is obtained an improved surface function which represents the surface of the improved progressive lens.

Abstract: The disclosure relates to progressive power or multifocal ophthalmic lens and methods and formers for making such lens. The optical power of such lens varies gradually from a near viewing zone to a distance viewing zone. Selected mathematical functions are progenitive of the lens and former shapes, and steps of the methods are characterized by various mathematical functions, and coordinate systems which are constrained to provided the desired transition of optical powers in an intermediate zone of the lens.