| 摘要 |
PROBLEM TO BE SOLVED: To obtain a small-sized high-performance super-wide-angle zoom lens covering a super-wide-angle area where the maximum angle of view exceeds 100 deg. and having comparatively large aperture ratio and variable power ratio by making three-degree aspherical coefficient in the specified aspherical expression of an aspherical lens in a 1st lens component satisfy a specified condition. SOLUTION: In this zoom lens that a variable power is executed by changing a distance between 1st and 2nd lens groups; the 1st lens group is provided with the 1st lens component, a 2nd lens component and a 3rd lens component in order from an object side. When it is assumed that height in a perpendicular direction to an optical axis is (y), a distance along the optical axis from the tangential plane of the apex of an aspherical surface at the height of (y) to the aspherical surface is S(y), the radius of curvature being reference is R, a conical coefficient is (k), and the n-degree aspherical coefficient is Cn, the aspherical surface of the aspherical lens in the 1st lens component is expressed by the expression. The three-degree aspherical coefficient C3 in the aspherical expression satisfies a condition; -7×10-3<=C3<=-1×10-6.
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