| 摘要 |
PROBLEM TO BE SOLVED: To provide a zoom lens, wherein the small size and the wide angle are attained and aberrations are suppressed. SOLUTION: In the zoom lens 100, a second lens group 120 includes at least one surface that is an aspheric surface, and during changing magnification, the second lens group 120, a third lens group 130, and a fourth lens group 140 are respectively capable of moving independently, with the position of the aperture 150 moving along a convex trajectory on the optical axis from the image side to the object side during changing magnification. Through operation in this manner, the zoom lens can be made inexpensive and compact, and efficiently corrects various types of aberration. Thus, at a high magnification ratio of 5 times or greater, the zoom lens affords a wide field exceeding approximately 78 degrees at the wide angle end, and affords a high performance compact zoom lens whose distortion is held to 3% or less. COPYRIGHT: (C)2009,JPO&INPIT
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