may be implemented such a multirange lens is able to alter the peripheral vision and correct astigmatism of the wearer contact lenses such as multirange contact lenses 10 50 and 76 are typically produced as described above by using a transparent material having one refractive index and adjusting curvatures of the zones of the material to form the required different powers transparent materials having variable refractive indices are known in the art such as are used to produce graded index grin lenses and a variable refractive index material may be used to produce a multirange contact lens having powers substantially as described above for lenses 10 50 and 76 all such lenses are assumed to be comprised within the scope of the present invention as will be appreciated by those skilled in the art for any region of a lens using a variable refractive index material the curvature of the zone of the region the base curve and the range and distribution of the refractive index of the material between the zone and the base curve all contribute to the overall power generated for the region it will thus be appreciated that the power of any specific zone the base curve and the transparent material.