| 摘要 |
PURPOSE:To enable the measurement of the uneven optical transmission loss of an optical fiber in its longitudinal direction without cutting the optical fiber by detecting the quantity of the light radiated from the side face of the optical fiber and measuring the optical transmission loss. CONSTITUTION:A measurement device is constituted of a light incident device A, a detection device B and an arithmetic device C. An optical fiber 22 drawn from a bobbin 23 passes through the device A and the device B, is taken off by a pair of nip rolls 25 driven at a specified speed and is taken up on a bobbin 24. A lens 30 is disposed in such a way that the image of a lamp is formed near the fiber 22 and a cover 32 is preferably made internal surface thereof of a material having a good reflectivity as it improves the efficiency of light incidence. Integration spheres 34, 35 are preferably of the spherical shape convered internally with a diffusion surface having a high reflectivity. An analog computer 40 calculates an optical transmission loss. It is possible to record continuously the fluctuation in the optical transmission loss of the optical fiber and to determine the distribution in the fiber axis direction by connecting a recorder 41 to the computer 40. |
