| 摘要 |
PROBLEM TO BE SOLVED: To provide: an imaging optical system which easily provides good imaging performance even with a reduced number of free-form surfaces acting as off-axial reflection surfaces; an image reading device; and a manufacturing method for the image reading device.SOLUTION: An imaging optical system includes first and second free-form surfaces acting as off-axial reflection surfaces, and a reflective aperture for guiding light rays from the first free-form surface to the second free-form surface, the first and second free-form surfaces being formed on a single optical element, where the reflective aperture and the optical element are configured to allow for changing relative positions thereof. |
