| 摘要 |
[Aim] To reduce size and cost, to widen an angle of view, and to achieve high performance in an imaging lens, and further to eliminate restrictions on an imaging device to be used. [Solution Means] An imaging lens (1) includes negative first lens (L1), negative second lens (L2), third lens (L3) of a plano-convex shape having a convex surface directed toward an object side or of a positive meniscus shape having a convex surface directed toward the object side, and fourth lens (L4) of a plano-convex shape having a convex surface directed toward an image side or of a positive meniscus shape having a convex surface directed toward the image side, which are arranged in this order from the obj ect side. Further, the following conditional formula (3) is satisfied: 1.0 < f �¢ 2 / f < 2.6 where
f: a focal length of an entire system, and
f2: a focal length of the second lens. |
