IMAGE CAPTURING LENS

• Main Authors: KUBOTA YOJI, YONEZAWA TOMOHIRO, HIRANO HITOSHI, KUBOTA KENICHI, KURIHARA ICHIRO
• Format: Patent
• Language: English; Japanese
• Published: 05.02.2015
• Subjects: OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICS; PHYSICS

PROBLEM TO BE SOLVED: To provide an image capturing lens which is both compact and wide-angle and also well corrected for aberrations.SOLUTION: An image capturing lens comprises a first lens L1 having positive refractive power, a second lens L2 having positive refractive power, and a third lens L3 having positive refractive power arranged in order from the object side to the image plane side. The first lens L1 and the third lens L3 each has a shape of a meniscus lens having an object-side surface which is convex near an optical axis. Defining P1 as refractive power of the first lens L1, P2 as refractive power of the second lens L2, P3 as refractive power of the third lens L3, f1 as a focal length of the first lens L1, and f3 as a focal length of the third lens L3, the image capturing lens configured as such satisfies the following conditional expressions: 5.0<(P1+P3)/P2<8.5, 6<f3/f1<30. 【課題】諸収差を良好に補正しつつ小型化と広角化との両立を図ることのできる撮像レンズを提供する。【解決手段】撮像レンズは、物体側から像面側に向かって順に、正の屈折力を有する第１レンズＬ１と、正の屈折力を有する第２レンズＬ２と、正の屈折力を有する第３レンズＬ３とを配置して構成される。第１レンズＬ１および第３レンズＬ３は、光軸近傍において物体側に凸面を向けたメニスカスレンズとなる形状である。当該構成において、第１レンズＬ１の屈折力をＰ１、第２レンズＬ２の屈折力をＰ２、第３レンズＬ３の屈折力をＰ３、第１レンズＬ１の焦点距離をｆ１、第３レンズＬ３の焦点距離をｆ３としたとき、撮像レンズは次の各条件式を満足する。５．０＜（Ｐ１＋Ｐ３）／Ｐ２＜８．５、６＜ｆ３／ｆ１＜３０。【選択図】図１