| 摘要 |
PROBLEM TO BE SOLVED: To provide an imaging lens which has a wide angle of view, a large diameter and a sufficiently small size and in which astigmatism, field curvature, chromatic aberration of magnification, color difference of coma aberration, distortion aberration and the like are sufficiently reduced, a desired resolution is obtained, high contrast is achieved from a fully open state of a diaphragm to a small open state thereof, disturbance of a point image does not occur even in the periphery of the angular field, and high performance is achieved in a range from a long distance to a short distance.SOLUTION: The imaging lens includes a first lens group G1 positioned on the object side and having positive refractive power and a second lens group G2 positioned on the image side and having positive refractive power, with an aperture diaphragm AD interposed therebetween. The first lens group G1 includes, in order from the object side, a first-F lens group G1F including a negative lens L11 and a positive lens L12, and a first-R lens group G1R including a negative lens L13 and a positive lens L14 and having positive refractive power. When focusing from a long distance object to a short distance object, the first-F lens group G1F and the first-R lens group G1R move so as to reduce the distance between them. |
