| 摘要 |
PURPOSE:To perform high-precision focusing detection by providing a transmitting means which disallows light with wavelength used for photometry to pass selectively and allows light with other wavelengths to pass between a light source device and a light guide. CONSTITUTION:Light incident in parallel to an optical axis 10 is reflected by a focusing mirror 12 to travel toward an image reforming lens 13, a filter 14 which allows only specific light to pass, a photodetecting element 15, and a light source 16 for focusing detection. The photodetecting element 15 as a photodetecting means is shaped in a disk having an opening such as a pinhole 17 in the center, and this disk has a photoelectric surface 18 as the top surface and a light shielding surface 19 as the reverse surface, preventing the photodetecting element 15 from being exposed directly to light from the light source for detecting whether an image is in focus or not from behind the pinhole 17. A camera 9 attached to an adapter 11 is loaded with a film 21 and when an erected image is formed on the film surface 21 through a pentagonal prism 22, a similar optical image is observed. |
