OPTICAL SYSTEM, IMAGING APPARATUS, AND OPTICAL INSTRUMENT

• Main Author: GYODA YUICHI
• Format: Patent
• Language: English; Japanese
• Published: 16.05.2016
• Subjects: OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICS; PHYSICS

PROBLEM TO BE SOLVED: To provide an optical system capable of optically changing a distortion aberration, while maintaining excellent image quality.SOLUTION: The optical system includes an aperture diaphragm, an A-th group moved when performing distortion adjustment, a B-th group arranged to be closer to an image side than the A-th group and moved with a locus different from that of the A-th group, when performing the distortion adjustment. When performing the distortion adjustment, the optical system is changed from a first optical state having a first distortion aberration to a second optical state having a second distortion aberration larger than the first distortion aberration. The focal lengths of the A-th group and the B-th group, the movement amounts of the A-th group and the B-th group when changing from the first optical state to the second optical state, distances on an optical axis from the aperture diaphragm to the A-th group and the B-th group, the distance on the optical axis from the lens surface closest to an object side of the A-th group to an image surface, and the entire optical length of the optical system satisfy a predetermined condition.SELECTED DRAWING: Figure 1 【課題】優れた画質を維持しつつ歪曲収差を光学的に変更可能な光学系を提供する。【解決手段】開口絞りと、歪曲調整に際して移動する第Ａ群と、第Ａ群よりも像側に配置され、歪曲調整に際して第Ａ群とは異なる軌跡で移動する第Ｂ群と、を有する光学系であって、歪曲調整に際して、光学系は、第１の歪曲収差を有する第１の光学状態から、第１の歪曲収差よりも大きい第２の歪曲収差を有する第２の光学状態に変化し、第Ａ群および第Ｂ群の焦点距離、第１の光学状態から第２の光学状態へ変化する際の第Ａ群および第Ｂ群の移動量、開口絞りから第Ａ群および第Ｂ群までの光軸上の距離、第Ａ群の最も物体側のレンズ面から像面までの光軸上の距離、および、光学系の光学全長は、所定の条件を満たす。【選択図】図１