PURPOSE: To use the spectacles both for shortsightedness and farsightedness by forming the upper and lower edges of a spectacle lens which extend in a horizontal direction horizontally vertically asymmetrically with the optical axis inserted and held and making the upper edge thicker than the lower edge. ;CONSTITUTION: The spectacle lens is formed slenderly in the lateral direction by cutting the upper and lower parts of a circular lens material 7 with the optical axis L of the circular lens material 7 inserted and held asymmetrically in the vertical direction so that the upper edge of the machined spectacle lens is thicker than the lower edge. In the case of a convex spectacle lens, the upper edge is cut large for the optical axis L and in the case of a concave lens, the lower edge is cut large. Therefore, the optical axis L of the convex lens is closer to the upper edge of the spectacle lens and the optical axis L of the concave lens is closer to the lower edge. Namely, the distance (a) from the optical axis L to the upper edge is set twice as long as the distance (b) to the lower edge by cutting a part of the material lens 7 to make the thickness of the lower edge is thinner than the thickness of the upper edge.;COPYRIGHT: (C)1994,JPO
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