Invisible edge lens

A method of producing an angled peripheral edge on an optically modified lens, cut to a desired size and shape and for use in frame-less spectacles for a user having an eye with a line of sight along an axis S (S being straight ahead) which is about O degrees when the user is looking directly ahead, and peripheral lines of sight P, the method comprising:

• entering a distance A, being a longitudinal measurement from the user's eye surface, adjacent to the center of the pupil, to points on an outer peripheral rim of the lens, into a computer program;
• and
• entering a distance B, being a lateral measurement from an optical center of the lens (axis S) to points on the outer peripheral rim, into the computer program;
• placing a lens optically modified to a user's prescription, cut to a desired size and shape, and having an inner concave lens surface bounded by an inner peripheral rim, and an outer convex lens surface bounded by an outer peripheral rim, in lens making equipment;
• modifying an edge of the lens to become an angled peripheral edge joining the inner peripheral rim and the outer peripheral rim according to the computer program incorporating the distance A and distance B to result in a manufactured lens in which the angled peripheral edge angle is less than any lines of sight P, but greater than any lines of sight P1 refracted at the inner peripheral rim through the lens;
• and
• causing a junction between the angled peripheral edge and the inner lens surface to form a cleanly machined vertex at the inner peripheral rim, and a function of the angled peripheral edge and the outer lens surface to form a vertex sufficiently radiused to remove a sharp edge at the outer peripheral rim,
• wherein an invisible zone is created between lines of sight P that pass the inner peripheral rim, and lines of sight P1 refracted at the inner peripheral rim through the lens material;
• wherein the angled peripheral edge is disposed completely within the invisible zone such that any lines of sight P that pass the inner peripheral rim do not strike the external surface of the angled peripheral edge nor the outer peripheral rim, and refracted lines of sight P1 within the lens body do not strike the internal surface of the angled peripheral edge nor the outer peripheral rim, such that the internal surface and external surface of the angled peripheral edge and the outer peripheral rim are not visible to the user in use.