| 摘要 |
Provided are: an optical system for observation in which the quantity of spatially intermediate image formation is small, loss in the amount of light arriving at an imaging element is minimized, and it is possible form a bright and clear image; and an imaging device provided with the optical system for observation. The optical system for observation is provided with a focusing group that comprises an objective lens and an image formation lens in order from the object side, and in which focusing is carried out by moving in the optical axis direction in accordance with variation in the object distance within the image formation lens. The objective lens shrinks a subject image and causes the result to enter a spatially intermediate image formation surface. The spatially intermediate image formation is enlarged by the image formation lens and image formation is carried out again on an imaging element. |
