An image scanning lens includes four lens components, each of which may be a
lens
element. From the object side of the image scanning lens, the first lens component
has positive refractive power and a meniscus shape with the convex surface on the
object side, the second lens component has a biconcave shape, the third lens component
has a biconvex shape, and the fourth lens component has negative refractive power
and a concave surface on the object side and may be a meniscus lens or a biconcave
lens component. The image scanning lens satisfies certain conditions related to
the focal lengths of the first, second, and fourth lens components of the image
scanning lens and to the relative partial dispersions of the lens elements. An
image scanning device, such as an image scanner, with an image pickup device, such
as a CCD, uses the image scanning lens.
