| 摘要 |
PURPOSE:To perform focusing detection with high accuracy by leading the incident light passing through the peripheral two regions of an objective lens to a spectral lens and mirrors and placing a focusing detecting element on the optical path of the mirrors. CONSTITUTION:Behind an objective lens 1 are provided a pair of mirrors 12 in symmetrical positions with an optical axis 2 as their axis. A concave lens 13 as a spectral lens for leading light to these mirrors is provided in ring form. Hence, the convave lens 13 does not obstruct the optical path to the finder optical system and film 11. A focusing detecting element 14 is disposed on the reflecting optical path of this mirror 12. Hence, by detecting the focusing from the incident light passing the peripheral two regions of the lens, the light for focus detection may be fetched without becoming hindrance to the incident light to the finder system or film, whereby the detection accuracy may be enhanced. |
