| 摘要 |
<p>In order to decrease various aberrations intrinsically provided on a lens for spectacles for correcting the visual power of severe short-sightedness, an objective piece is formed into a concave and non-spherical surface. An eye piece is made to be an unpolished surface which is to be polished into a concave shape, so that a finished product of lens may be produced. Or, the eye piece is formed into a concave shape by casting similarly to the objective piece, so that a finished product of lens may be produced.</p> |
