Imaging lens and imaging apparatus using imaging lens
View Patent ↗An imaging lens includes, in order from an object side, a positive first lens group, a stop, and a positive second lens group. The first lens group includes, in order from the object side, a first lens, which is a negative meniscus lens having a convex object-side surface, and a second lens having a positive power and including a convex image-side surface. The second lens group includes, in order from the object side, a third lens having a negative power and including a concave object-side surface, a fourth lens having a positive power and including a convex image-side surface, a fifth lens, which is a biconvex lens, and a sixth lens, which is a meniscus lens having a negative power and including a convex surface facing an image side. Each of the first to sixth lenses is a single spherical glass lens.
1. An imaging lens consisting of:
a first lens group having a positive power;
a stop; and
a second lens group having a positive power,
wherein the first lens group, the stop, and the second lens group are arranged in this order from an object side,
the first lens group includes, in order from the object side,
a first lens, which is a meniscus lens having a negative power and including a convex surface facing the object side, and
a second lens that has a positive power and includes a convex image-side surface,
the second lens group includes, in order from the object side,
a third lens that has a negative power and includes a concave object-side surface,
a fourth lens that has a positive power and includes a convex image-side surface,
a fifth lens, which is a biconvex lens, and
a sixth lens, which is a meniscus lens having a negative power and including a convex surface facing an image side, and
each of the first to sixth lenses is a single spherical glass lens.
2. The imaging lens according to claim 1 ,
wherein the imaging lens satisfies the following conditional expression:
1.1 <f 36 /f< 1.7
where f indicates a focal length of an entire imaging lens system, and f 36 indicates a focal length of the second lens group.
3. The imaging lens according to claim 1 ,
wherein the imaging lens satisfies the following conditional expression:
−1.4 <f 1 /f 2<−0.7
where f 1 indicates a focal length of the first lens and f 2 indicates a focal length of the second lens.
4. The imaging lens according to claim 1 ,
wherein the imaging lens satisfies the following conditional expression:
1.1 <R 11 /R 12<2.0
where R 11 indicates a curvature radius of an image-side surface of the fifth lens, and R 12 indicates a curvature radius of an object-side surface of the sixth lens.
5. The imaging lens according to claim 1 ,
wherein the imaging lens satisfies the following conditional expression:
νd3<20
where νd 3 indicates the Abbe number of the third lens at the d-line.
6. An imaging apparatus comprising:
the imaging lens according to claim 1 ; and
an imaging device that converts an optical image formed by the imaging lens into an electric signal.