Imaging lens system
An imaging lens system is provided. The imaging lens system includes a lens group including a plurality of lenses; and an optical path conversion member disposed between the lens group and an imaging plane. The lens group may include a first lens, a second lens, a third lens, and a fourth lens sequentially disposed from an object side toward the imaging plane. The optical path conversion member may reflect light emitted from the lens group two or more times to increase a rear focal length of the lens group (or a distance from an image-side surface of a lens disposed on a rearmost side of the lens group to the imaging plane).
1 . An imaging lens system, comprising:
a first lens, a second lens, a third lens, a fourth lens, and an optical path conversion member sequentially disposed from an object side toward an imaging plane,
wherein the imaging lens system comprises a total of four lenses,
wherein the first lens has a convex image-side surface,
wherein the fourth lens has negative refractive power, a convex object-side surface in a paraxial region, and a concave image-side surface in a paraxial region, and
wherein 0.70<PL/TTL<0.90,
where PL is a distance from an incident surface of the optical path conversion member to an exit surface of the optical path conversion member, and TTL is a distance from an object-side surface of the first lens to the imaging plane.
2 . The imaging lens system of claim 1 , wherein the first lens has a convex object-side surface.
3 . The imaging lens system of claim 1 , wherein the second lens has a concave object-side surface.
4 . The imaging lens system of claim 1 , wherein the second lens has a concave image-side surface.
5 . The imaging lens system of claim 1 , wherein the third lens has a convex object-side surface.
6 . The imaging lens system of claim 1 , wherein the third lens has a concave image-side surface.