IMAGING OPTICAL SYSTEM AND IMAGING APPARATUS

To provide an imaging optical system capable of suppressing lens eccentricity caused by a lens shift and a lens tilt, without reducing a diameter and an imaging apparatus.SOLUTION: An imaging optical system 1 includes a plurality of lenses L1, L12, L13, L14, L15, and L16 and a cylindrical support structure 2 for holding the plurality of lenses inside. The plurality of lenses include a first lens L11 which has a large-diameter part 11A which is arranged inside the first inner diameter part 2a of the inner peripheral surface of the support structure 2 and has a gap S in a radial direction between itself and the first inner diameter part 2a and a small-diameter part 11B which is held by the second inner diameter part 2b of the inner peripheral surface and positioned in the radial direction with respect to the support structure 2 and whose diameter is smaller than that of the large-diameter part 11A.SELECTED DRAWING: Figure 1 【課題】口径を小さくすることなく、レンズシフト及びレンズチルトによるレンズ偏芯を抑制可能な撮像光学系及び撮像装置を提供する。【解決手段】本発明の撮像光学系１は、複数のレンズＬ１，Ｌ１２，Ｌ１３，Ｌ１４，Ｌ１５，Ｌ１６と、前記複数のレンズを内部に保持する筒状の支持構造体２と、を具備し、前記複数のレンズは、前記支持構造体２の内周面の第１の内径部２ａの内部に配置され、該第１の内径部２ａとの間に径方向の隙間Ｓを有する大径部１１Ａと、前記内周面の第２の内径部２ｂに保持され、前記支持構造体２に対して径方向に位置決めされ、前記大径部１１Ａより径の小さい小径部１１Ｂと、有する第１のレンズＬ１１を備える。【選択図】図１