Essilor

About: Essilor is a company organization based out in Braunschweig, Germany. It is known for research contribution in the topics: Lens (optics) & Coating. The organization has 1709 authors who have published 2126 publications receiving 18034 citations. The organization is also known as: Essilor International.

Custom eyeglass manufacturing method

Abstract: Two or more images captured from digital cameras record an image of spectacle frames on a subject. The image is analyzed using automated image-processing techniques to identify the relation of specific points of interest on the frame to the location of each of the subject's eyes allowing the optical center of the lens to be placed in the correct location in the frames.

Optical lens for correcting astigmatism

Abstract: The present invention relates to an optical lens for correcting astigmatism. It includes diffractive components whose outlines are delimited by conic section curves having non-degenerate centers. More precisely, in accordance with the invention, the lens includes adjacent diffractive components having hyperbolic or elliptical outlines with a periodicity in r 2 in two mutually orthogonal directions x and y intersecting on the axis of the lens and coinciding with the main axes of the hyperbolas or of the ellipses, which are determined respectively by the equations: Δr x 2 =2λ|f x |; and Δr y 2 =2λ|f y |; in which: Δr x 2 represents the periodicity in r 2 along the x direction; Δr y 2 represents the periodicity in r 2 along the y direction; λ represents the mean utilization wavelength; f x represents the desired focal length in the X direction; and f y represents the desired focal length in the Y direction.

Abrasion-resistant coating compositions containing hydrolised silanes and aluminium compounds; coated articles resistant to abrasion and shocks

Abstract: Curable composition for antiabrasion coating, including the constituents A - a hydrolysate of an epoxytrialkoxysilane, B - a hydrolysate of a silane of formula (I) in which each of T and T produces an OH group by hydrolytic treatment and Z and Z are unreactive organic groups, C - colloidal silica, D - a specific aluminium catalyst, E - optionally, an organic solvent whose boiling point is between 70@C and 140@C, and the corresponding coated articles, optionally treated against reflections.

Method for forming plastic optical quality spectacle lenses

Abstract: A fast, relatively inexpensive and simple method is disclosed for producing a finished plastic multifocal or progressive lens from a preformed lens which has a predetermined lens correction (i.e., curvature or prescription) at its optical center. The method comprises providing a mold; providing an optical quality resin composition; providing a performed plastic lens contacting the preformed lens with the mold such that the surfaces of the preformed lens and the mold form a cavity enclosing the resin composition; and curing the resin composition. The cavity formed by the performed lens and the mold is shaped, among other purposes, (1) to correspond to the desired change in curvature, and (2) such that the lens correction at the optical center of the resulting lens is substantially the same (preferably the same) as the predetermined lens correction at the optical center of the preformed lens. The preformed lens may also be cast with a thin non-prescription layer which acts as a carrier for the multifocal or progressive region of the finished lens. The methods disclosed allow casting of lenses without employing expensive conventional optical gaskets. The methods also allow for simpler relocation of the optical center to the proper position with respect to the multifocal or progressive prescription, preferably without using conventional optical gaskets or optical center movers.