IMAGING OPTICAL SYSTEM AND IMAGING DEVICE USING SAME

摘要

Provided is an imaging optical system wherein generation of flare and ghost which cause image quality deterioration can be sufficiently suppressed.  An imaging optical system (7) is provided with, in sequence from an object side to an image surface side, an aperture stop (5), a biconvex first lens (1) having a positive power as an optical member, a second lens (2) which has a negative power and is composed of a meniscus lens having a concave lens surface on the image surface side, a third lens (3) which has a positive power and is composed of a meniscus lens having a convex lens surface on the image surface side, and a fourth lens (4) which has a negative power and has a concave lens surface in the vicinity of an optical axis on the image surface side.  On an effective aperture section on a lens surface (e) on the image surface side of the second lens (2), a total reflection surface which totally reflects incoming beams outside the angle of view is provided.