| 摘要 |
PURPOSE:To perform speedy focusing and photograpy with a simple constitution, by providing a focusing detection part which detects whether an image is in focus or not, in a photographic adapter attached freely detachably to an endoscope ocular part or a photographing device attached through the intervention of the photographic adapter, and placing the optical system of the endoscope in an in-focus state by the signal of a focusing detection part. CONSTITUTION:Light from a light source 12 for focusing travels along an optical axis 7 through the opening part 15 of a photoelectric element 11 such as a pinhole and is projected upon a subject 25 in front through an ocular lens 34. The light reflected by the subject 25 returns to the photoelectric element 11 through the ocular lens 34 again. When the subject 25 is in focus, i.e. at a position (b), an output level Pb of the photoelectric element 11 is minimized and when it is closer or farther than it, an output level Pa or Pc increases correspondingly. Thus, a minimum signal output corresponds to the in-focus position so a focus ring 33 is rotated to move the ocular lens 34, thereby obtaining the in-focus position of the ocular lens 34 on the basis of the minimum output of the photoelectric element 11. |
