| 主权项 |
1. An imaging lens substantially consisting of five lenses, including:
a first lens having a positive refractive power and a convex surface toward the object side; a second lens having a negative refractive power and a concave surface toward the object side; a third lens having a positive refractive power and is of a meniscus shape with a convex surface toward the object side; a fourth lens having a positive refractive power and is of a meniscus shape with a concave surface toward the object side; and a fifth lens having a negative refractive power and a concave surface toward the image side, the surface thereof toward the image side being of an aspherical shape having at least one inflection point within a range from an intersection of a principal light ray at a maximum angle of view with the surface toward the image side inwardly toward the optical axis in the radial direction, provided in this order from the object side; the imaging lens satisfying the following conditional formulae:
1.25<f/f1<3 (1)0.57<f/f4<3 (2)−1.87<f/f5<−0.5 (3)1<TTL/(f·tan ω)<1.56 (4) wherein f is the focal length of the entire system, f1 is the focal length of the first lens, f4 is the focal length of the fourth lens, f5 is the focal length of the fifth lens, TTL is the distance from the surface of the first lens toward the object side to the imaging surface along the optical axis in the case that back focus is an air converted length, and ω is the half value of a maximum angle of view when focused on an object at infinity. |
