| 摘要 |
PURPOSE:To obtain an invariably definite image signal and to detect and part accurately by separating a lens barrel and a camera head and moving the camera head freely in directions of an optical axis. CONSTITUTION:This detector consists of a projector, the telecamera 3, a device which processes a video signal from the camera 3, etc. The camera 3 has the lens barrel 11 fixed to a base 13 and the camera head 14 separately, and the head 14 is fitted to the base 13 movably in the directions of the optical axis. Further, the camera 3 is equipped with a jogging device 18 which displaces the head 14 in the directions of the optical axis. The signal from the camera 3 is compared with a reference voltage preset by a video signal processor to judge whether the end part reaches a specific position or not. Further, when the diameter of a tube increases and the distance between the surface of the tube and camera 3 becomes short, a photographic lens becomes out of focus on the photodetection surface of an image pickup tube or image pickup plate. In this case, the lens in put in focus on the photodetection surface by the device 18. |
