| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an imaging lens system with high resolution in an embodiment suppressing enlargement in a size of the imaging lens system.SOLUTION: The imaging lens system comprises, in order from an object side, at least: a first lens group including a first lens convex on the object side; a second lens group including a second lens concave on an image side; a third lens group including a third meniscus lens concave on the object side; a fourth lens group including a fourth meniscus lens concave on the object side; and a fifth lens group including a fifth meniscus lens having an aspherical surface with an inflection point arranged on the object side. When a cross section is viewed in a plane surface including an optical axis, the fifth lens is an aspherical lens that has first and second inflection points at which an extension direction of a contour line of the fifth lens changes firstly on the object side and on an image-formation side, respectively toward an outer periphery from a center. When a focal length of the imaging lens system is f, a height of the first inflection point from the optical axis is i1 and a height of the second inflection point is i2, the imaging lens satisfies i1/f<0.20 and i2/f<0.26.</p> |
