| 摘要 |
<p>PURPOSE:To reduce an investment in facilities and to measure a temperature distribution with high economical efficiency by using a single-mode fusion-spliced coupler which is connected in series and utilizing an existing single-mode optical fiber as an optical fiber for sensing. CONSTITUTION:A light source 1 is driven by a pulse driving circuit 12 which is controlled by a computer 11 to generate a light pulse repeatedly. Then 2nd fusion-spliced couplers 2 and 3 are connected in series by fusion splicing while two single-mode optical fibers are extended longitudinally. A cut filter 5 is connected to the other end of the fusion-spliced coupler 3 on the side of the light source and includes a multi-mode optical fiber on its output side to extract a wavelength component of Stokes light obtained from the single-mode fiber 4 for sensing. A digital averager 10 processes and transfers Rayleigh light and Stokes light detected by photodetector 8 and 6 to the computer 11 to measure the temperature distribution in an area long the fiber 4.</p> |
