Toroidal lens for sunglasses

A lens for eyeglasses, said lens adapted for mounting on a wearer by means of an eyeglass frame having a lens receiving portion and a pair of ear stems, said lens being suitable for participation in active sports, such as biking, skiing and the like, said lens comprising:

• a unitary pane having an upper edge and a lower edge, said lower edge having a nose piece opening formed therein for mounting said lens on the nose of the wearer, thereby mounting said lens in cooperation with the eyeglass frame on the head on the wearer, said upper edge of said lens having a generally upwardly arcuate configuration to maximize the surface area of said lens above the eye level of said wearer in order to intercept light rays incident from above,
• said nose piece opening having an upper extremity, the distance separating the upper extremity of the nose piece and the upper edge of the pane being defined as d1, and the distance separating the upper edge of the pane and the lower edge of the pane being defined as d.sub.2, wherein d.sub.1 is in the range between about 3/4-inch and 11/2 inches, and d.sub.2 is in the range from about 13/4 inches to 23/4 inches, said dimensions providing optimum interception of light rays while allowing sufficient ventilation around the face of the wearer while participating in active sports,
• said lens having a first arcuate cross-sectional configuration in a horizontal direction from a first ear stem to a second ear stem, having a radius designated R.sub.1, wherein the arc length (L) of said lens is in the range of about 51/2 inches to about 7 inches,
• said lens having a second arcuate cross-sectional configuration in a vertical direction, having a radius designated R.sub.2 ;
• and
• means for mounting said lens on said lens-receiving portion of said frame, wherein R.sub.1 <R.sub.2, and R.sub.1 is in the range of about 2 inches to about 4 inches.