3. The patient must have a spectacle corrected spherical refractive error between +5.50 D and -11.00 D with less than or equal to 1.00 D refractive cylinder. The parameters of the Ciba Vision Night and Day Lenses range from +6.00 to -10.00 D, and can correct the refractive range of this population. Monovision correction will be allowed only if the near eye does not exceed +6.00 D.