JP2880229B

PURPOSE:To measure the state of the wall surface in the reactor in a short time with high accuracy by inserting a sensor head whose angle between the line connecting laser light and a subject and the line connecting the subject and a photodetection part is fixed into the nuclear fusion reactor, and adjusting the distance between the sensor head and subject. CONSTITUTION:A fixed light projector is fitted to a light projection part 1, a fixed TV camera is fitted directly to the photodetection part 2, and the distance to the subject 3 is adjusted by a moving link 6. A driving device 7 and a moving cylinder 5 are operated according to a signal from a personal computer 10 and the moving link 6 is operated to align the position of the point where the laser light 4 and the center line of the photodetection part 2 intersect each other to the subject 3 with the level of the surface of the subject 3, so that the photodetection part 2 measures the surface state of the subject 3 continuously. Measurement data when the subject is assembled completely is inputted to the personal computer 10 and the surface state of the subject 3 in the reactor is measured similarly after the nuclear fusion reactor is used for a certain time and compared with measurement data when the reactor is in a sound state to find a worn part and its wear quantity.