| 摘要 |
A spectacles lens is described with a front and rear (eye-facing) surface and with a variable refractive index. The lens is designed to assist in correcting sight defects. The lens of the invention is characterized by at least a family of equipotential surfaces (n(x,y,z) = const.) with a constant refractive index, which, at all points along the normals to the surfaces, are the same distance apart (i.e. parallel surfaces), and the surfaces or the extensions of the surfaces intersect the line which joins the lens vertex of the front surface and the rear surface. |
