| 摘要 |
<p>An optical system for a laser beam printer uses, as a first image forming system, an anamorphic lens whose first surface facing a light source has a refraction power rotation-symmetrical with respect to the optical axis, and whose second surface is a toric surface having refraction powers different in horizontal and vertical directions. A coupling optical system for an optical disk information recording apparatus comprises an anamorphic single lens whose first surface is a toric surface correcting aberration only in a first direction in which the radiation angle of a light beam emitted from a light source is larger than that in a second direction perpendicular to the first direction, and whose second surface is a toric surface correcting aberration only in the second direction.</p> |
