An object of the present invention is to suppress an influence due to temperature
change and various aberrations. It is a projection lens which projects an image
on a surface of a screen (magnified side). A first group I having a negative refractive
power and a second group II having a positive refractive power are arranged in
order from a magnified side toward a reduced side. The first group I is configured
to arrange a first lens and a second lens in order from the magnified side, and
the second group II is configured to arrange a third lens to a seventh lens. The
first and second lenses are a negative meniscus lens whose both surfaces are formed
by the aspherical surface in which an area near an optical axis of the surface
on the magnified side is a concave surface. The third lens is a cemented lens in
which a bi-concave lens is cemented to the surface on the reduced side of a bi-convex
lens. The fourth lens is a positive meniscus lens whose both surfaces are formed
by the aspherical surface, and a convex surface of the positive meniscus lens faces
toward the reduced side. The fifth lens is the cemented lens in which the bi-concave
lens is cemented to the surface on the reduced side of the bi-convex lens. The
sixth lens is a positive lens whose strong convex surface faces toward the reduced
side. The seventh lens is the positive lens whose both surfaces are a convex surface.