| 摘要 |
<p>The eyeglass lenses consisting of a highly refractive glass have a circular or oval lenticular ground-out portion. The lenticular ground-out portion is ground into a negative base lens. The diameter of the lenticular groundout portion measures 20 to 30 mm. The transition of the lenticular ground-out portion into the negative base lens is continuous and in an aspheric form. The eyeglass lenses are substantially thinner and therefore lighter than the eyeglass lenses of the customary type and cause no "bull's eye" effect.</p> |
