| 摘要 |
PROBLEM TO BE SOLVED: To provide a wide-angle compact image capturing lens that offers a small F-number and good aberrations.SOLUTION: An image capturing lens comprises, in order from the object side, an aperture stop ST, a bi-convex first lens L1 having positive refractive power, a second lens L2 having a concave surface on the image side and negative refractive power, a meniscus-shaped third lens L3 having a convex surface on the image side and positive refractive power, and a bi-aspherical fourth lens L4 having a concave surface on the image side and negative refractive power. The image capturing lens has an F-number less than 2.4 and satisfies the following conditional expressions (1), (2), (3): (1) 0.8<ih/f<0.95, (2) TLA/2ih<0.9, (3) -4.0<r3/r4<6.0, where ih represents a maximum image height, f represents a focal length of the entire image capturing lens system, TLA represents an optical axial length (total optical length) from an object-side surface of an optical element located on the most object side to an image plane after filters are removed, r3 represents a curvature radius of an object-side surface of the second lens, and r4 represents a curvature radius of an image-side surface of the second lens. |
