IMAGING OPTICAL SYSTEM AND IMAGING APPARATUS AND MOBILE OBJECT

• Main Authors: OGINO SHIMPEI, ICHII DAISUKE, SUZUKI KENSUKE, HATASHITA CHIEKO, NAKANUMA HIROSHI
• Format: Patent
• Language: English; Japanese
• Published: 05.10.2022
• Subjects: OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICS; PHYSICS

To achieve a novel imaging optical system that can reduce an influence of ghost light.SOLUTION: An imaging optical system is provided, forming an image in which an imaging object is a physical body on an imaging plane. The imaging optical system is constituted with a lens system and a filter F1 arranged from an object side toward an image side. The lens system is comprised of five groups. The filter F1 has a parallel plane plate-shape, and is arranged orthogonally to an optical axis of the lens system. A first group G1 of the lens system is comprised of a first lens L1 serving as a negative meniscus lens with a convex surface directed at an object side. A radius of curvature on an object side surface of the first lens L1: R11, a focal length of an entire system: f, a distance between an object side surface of the filter F1 and an image plane IS: Df and an overall length of the entire system:L satisfy a conditional expression: (1) 0.55<(R11/f)×(Df/L)<1.00 .SELECTED DRAWING: Figure 1 【課題】ゴースト光の影響を軽減できる新規な撮像光学系を実現する。【解決手段】撮像対象を物体とする像を、撮像面上に結像させる撮像光学系であって、前記物体の側から像側に向かってレンズ系とフィルタＦ１とを配してなり、前記レンズ系は５群構成で、前記フィルタＦ１は平行平板状で前記レンズ系の光軸に直行するように配置され、前記レンズ系の第１群Ｇ１は、物体側に凸面を向けた負メニスカスレンズである第１レンズＬ１により構成され、前記第１レンズＬ１の物体側面の曲率半径：Ｒ１１、全系の焦点距離：ｆ、前記フィルタＦ１の物体側面と像面ＩＳとの距離：Ｄｆ、前記全系の全長：Ｌが、条件式：（１） ０．５５ ＜（Ｒ１１／ｆ）×（Ｄｆ／Ｌ）＜ １．００を満足する。【選択図】 図１