| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical system that is not affected by flare light, is reduced in size, and has high resolving power, and is configured to photograph an image which has 360° omnidirectional angle of view, or project an image at 360° omnidirectional angle of view. <P>SOLUTION: The optical system includes: a front group 10 including two reflection surfaces and two transmission surfaces which are rotational symmetry around the center axis 1; a rear group 20 of positive power, which is rotational symmetry around the center axis; and an aperture 5 disposed coaxially to the center axis. The luminous flux incident on the front group is transmitted through the first transmission surface 11, and reflected by the first reflection surface 12 disposed opposite to the first transmission surface across the center axis toward a direction opposite to the image surface, and also, reflected by the second reflection surface 13 disposed on the same side as the first reflection surface 12 with respect to the center axis toward the image surface direction, then, transmitted through the second transmission surface 14, to go out outside a transparent medium, then, image-formed on the image surface 30 through the rear group 20. The position of an incident pupil 6Y in the cross section including the center axis 1 is different from the position of the incident pupil in the cross section perpendicular to the cross section and including the central ray 2<SB>0</SB>of the luminous flux. <P>COPYRIGHT: (C)2011,JPO&INPIT |
