In a second embodiment of the invention, one optical element consists of two separate curves, {HEAD ~ one aspheric curve} on {TAIL ~ the concave side} of the optic, and one curve of the standard conic curve family on the convex side of the optic 
on
In a second embodiment of the invention , one optical element consists of two separate curves , { HEAD ~ one aspheric curve } on { TAIL ~ the concave side } of the optic , and one curve of the standard conic curve family on the convex side of the optic
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH