| 摘要 |
PROBLEM TO BE SOLVED: To enable focus detection to be accurately executed by appropriately setting the respective elements of an optical means for focus detection provided on the image surface side of an objective lens (photographing lens). SOLUTION: A 1st reflection mirror 4 is arranged obliquely to the optical axis 1 on the image surface side of the objective lens 101. The light incident side of an image reformation lens block 9 equipped with an aspherical surface and a diffraction lens surface is a single concave aspherical surface having the center on the optical axis of the lens 101 deflected by the mirror 4, and the exit side thereof is composed of two pairs of convex lens surfaces 9e,...9g,... that are made eccentric in the opposite direction to each other. A detection system using luminous flux passing through some element separates the exit pupil of the objective lens in a longitudinal direction, while a detection system using the luminous flux passing through another element separates the exit side of the objective lens in the lateral direction. The 1st focus detection system separates a pupil in the longitudinal direction and the 2nd detection system separates the pupil in the lateral direction. Namely, a secondary object paired by separating the pupil of the objective lens on a 2nd plane PL2 orthogonally crossing a 1st plane is formed on a photoelectric conversion element. |
