| 摘要 |
PROBLEM TO BE SOLVED: To provide an imaging lens that corrects aberrations satisfactorily, though it is compact. SOLUTION: The imaging lens is constituted by arranging, in order from an object side, a stop ST, a first lens L1 that is biconvex near an optical axis, a negative second lens L2 that has a meniscus shape directing its convex surface toward the object side near the optical axis, a positive third lens L3 that has a meniscus shape directing its concave surface toward the object side near the optical axis, and a positive fourth lens L4 that has a meniscus shape directing its convex surface toward the object side near the optical axis. When a focal length of the lens entire system is denoted as f, and a distance on the optical axis from a surface on the object side of the first lens L1 to a surface on the image surface side of the fourth lens L4 is denoted as L14, they satisfy conditional expression: 0.5<L14/f<0.8. COPYRIGHT: (C)2011,JPO&INPIT |
