TH3642A - How to produce glasses based on myopia - Google Patents

Abstract

The required curvature, corresponding to the desired lens power, is calculated, and the curvature called transverse curvature is calculated for torus finishing, and the curvature is calculated according to the desired field of view. The lens is then assembled onto a lens making machine and the central concave surface (3) is finished according to the principal curvature, and then the edge of the lens (2) is finished around the central concave surface (3) according to the second curvature, and the central concave surface (3) of the lens, which was mechanically treated, is finished and polished in sequence using a tool with a convex surface corresponding to the principal curvature. The edge of the lens (2) is then finished and polished at least once each using a tool with a convex surface corresponding to the second curvature, with the more common use of a partially flexible intermediate between the tools and a finishing/polishing plate.

Claims (5)

1. The manufacturing process of eyeglasses for nearsighted individuals begins with a semi-finished lens containing a slight concave portion at its inner center. The process involves: a) Calculating the necessary baseline curvature from the required lens power; b) Calculating the secondary curvature of the lens based on the required field of vision; c) Placing the lens in a lens-making machine and polishing the concave portion at its center to the baseline curvature; d) Polishing the edges of the lens around the concave portion at its center to the aforementioned secondary curvature; e) Polishing and buffing the concave portion at its center using a tool with a radius of convexity equal to the baseline curvature; f) Polishing the edges of the lens around the concave portion at least once using a tool with a radius of convexity equal to the secondary curvature, and by placing a flexible center between the tool and the final polishing plate during the final polishing process. This allows the flexible center to conform to the curvature of the lens during the final polishing. 2. The method under claim 1, specifically the torus polishing method, also includes calculating the transverse curvature of the spectacle lens and, in addition, performing polishing at the center using a lens-making machine to achieve the transverse curvature for such torus-like polishing. 3. The method under claim 1 also includes the use of such flexible central part made of a material which is sufficiently flexible to perform final finishing of the edges around the central recess or to polish the lens edges around the central recess. 4. The method under claim 1 also involves the use of such flexible central material made of a water-impermeable material at least on the side that interlocks with the decorative or polished panel. 5. The method under claim 1 also involves applying a high degree of pressure to the flexible central part of the lens, around the central concave section and the continuation between the central concave section and the edges surrounding the central concave section (Clause 5, page 2, figure 5).