| 摘要 |
PURPOSE:To compensate various aberration efficiently in spite of a large angle of view by arranging a non-spherical surface with a shape found from a specific formula in the 1st diverging lens group. CONSTITUTION:A non-spherical surface is arranged in the 3rd position from the side of an object and the spherical surface is equipped with a shape found from the radius R of curvature of a standard spherical surface, height H perpendicular to the optical axis and the quantity X of shift in the optical axis direction when the vertex of the standard spherical surface is made coordinate point and the advancing direction of the rays of light is made positive. In addition, the focal distance is made ''1'' and the radius Ri of curvature of the i-th lens from the object side, the lens thickness and air interval D1 of the i-th lens from the object side, the refractive index Ni of the glass of the i-th lens, and Abbe's number v1 satisfy the values shown in an annexed table (omitted). |
