PURPOSE: To provide a gauss type photographic lens in which spherical aberration and sagital coma are satisfactorily corrected with a little lens number.
CONSTITUTION: In a gauss type photographic lens having a front group GF of positive refracting power which has, in order from object side, a positive lens component L1 having a strong convex surface turned on the object side and a negative lens component L2 having a strong concave surface on image side, a rear group GR of positive refracting power which has, in order from the image side, a negative lens component L3 having a concave surface on the object side, a positive lens component L4, and at least one positive lens component L5 having a strong convex surface turned on the image side, and a diaphragm S arranged between the front group and the rear group, and also having a six-piece structure as the whole, at least one of the lens components L1, L2 of the front group GF is an axial type refractive index distribution lens having a distribution such that the refractive index is increased from the object side to the image side.
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