IMAGING LENS SYSTEM AND IMAGING APPARATUS INCLUDING THE SAME

PROBLEM TO BE SOLVED: To provide a compact and inexpensive imaging lens system which can image a wide angle of view, is excellent in telecentricity, and has excellent resolution performance.SOLUTION: The imaging lens system comprises, in order from an object side, a first lens which has negative power and is concave to an image side, an aperture diaphragm, a second lens which has positive power and is convex to the image side, and a third lens which has positive power and is convex to the image side. The object-side lens surface of the first lens is concave to the object side in the vicinity of an optical axis and has an inflection point. The maximum value α of the tangential angle of the image-side lens surface of the first lens satisfies 45°≤α≤70°.SELECTED DRAWING: Figure 1 【課題】広い画角を撮像可能で、テレセントリック性に優れ、かつ、良好な解像性能を有する、コンパクトかつ安価な撮像レンズ系を提供する。【解決手段】物体側から順に、負のパワーの像側に凹形状の第１レンズと、開口絞りと、正のパワーの像側に凸形状の第２レンズと、正のパワーの像側に凸形状の第３レンズとからなり、第１レンズの物体側レンズ面は、光軸近傍で物体側に凹形状であり、かつ、変曲点を有し、第１レンズの像側レンズ面の接線角の最大値αが４５°≦α≦７０°を満足する。【選択図】 図１