| 摘要 |
PROBLEM TO BE SOLVED: To provide a compact and high-performance image capturing lens compatible with recent portable terminals or the like with reduced thickness.SOLUTION: An image capturing lens comprises, in order from the object side, a positive first lens L1 having a convex surface on the object side, an aperture stop ST, a negative second lens L2 which is meniscus-shaped with a concave surface facing the object side and is bi-aspherical, and a positive third lens L3 which is meniscus-shaped with a concave surface facing the image side and is bi-aspherical, where the second lens has a diffractive optical surface formed on the object-side surface, and the third lens has an inflection point positioned off an optical axis on each of an object-side surface and on the aspherical surface on the image side. The image capturing lens satisfies conditional expressions (1) to (4): (1) 8.0<fdoe/f<26.0, (2) 20<&ngr;d1-&ngr;d2<40, (3) 20<&ngr;d3-&ngr;d2<40, and (4) 0.8<ih/f<0.95, where fdoe represents a focal length of the diffractive optical surface, f represents a focal length of the entire image capturing lens system, &ngr;di represents an Abbe number of an i-th lens for the d-ray, and ih represents a maximum image height. |
