Imaging lens system, camera module, in-vehicle system, vehicle
An imaging lens system includes, sequentially from an object side toward an image side: a front lens group Gf including: a first lens, which is a meniscus lens having negative power with an object-side surface whose convex surface faces the object side; a second lens, which is a meniscus lens with the object-side surface whose concave surface faces the object side; and a third lens having positive power; an iris; and a rear lens group Gr including: a fourth lens having positive power; a fifth lens, a sixth lens constituting a cemented lens; and a seventh lens. The imaging lens system satisfies a following Expression (1): 2.0< Frg/F <3.0 (1) where Frg is a composite focal length of the rear lens group Gr and F is a focal length of an entire optical system.
1 . An imaging lens system comprising, sequentially from an object side toward an image side:
a front lens group comprising:
a first lens, the first lens being a meniscus lens having negative power with an object-side surface whose convex surface faces the object side;
a second lens, the second lens being a meniscus lens with the object-side surface whose concave surface faces the object side; and
a third lens having positive power:
an iris; and
a rear lens group comprising:
a fourth lens having positive power;
a fifth lens and a sixth lens constituting a cemented lens; and
a seventh lens, wherein the imaging lens system satisfies a following Expression (1):
2.0< Frg/F< 3.0 (1)
where Frg is a composite focal length of the rear lens group and F is a focal length of an entire optical system, wherein
the third lens is a biconvex lens,
the fourth lens is a biconvex lens,
a convex surface of an object-side surface of the fifth lens faces the object side, and
a concave surface of an image-side surface of the sixth lens faces the image side.
2 . The imaging lens system according to claim 1 , wherein the imaging lens system a following Expression (2):
( L 1−STOP)/ F< 3.5 (2)
where L 1 −STOP is a distance on a center optical axis between the object-side surface of the first lens and the iris.
3 . The imaging lens system according to claim 1 , wherein the imaging lens system a following Expression (3):
−0.7< F 1/ F 3<−0.4 (3)
where F 1 is a focal length of the first lens and F 3 is a focal length of the third lens.
4 . The imaging lens system according to claim 1 ,
wherein the imaging lens system satisfies a following Expression (4):
−1.8< F 1/ F<− 1.5 (4)
where F 1 is the focal length of the first lens.
5 . A camera module comprising:
the imaging lens system according to claim 1 ; and
a capturing element configured to convert light condensed through the imaging lens system into an electrical signal.
6 . An in-vehicle system mounted on a car comprising:
the camera module according to claim 5 ; and
an information processing apparatus configured to process a captured image output from the capturing element of the camera module and recognize an object in the captured image.
7 . A vehicle on which the in-vehicle system according to claim 6 is mounted, further comprising an output apparatus configured to output information to a crew, wherein the information processing apparatus is configured to output recognition information about the object to the output apparatus.