| 摘要 |
<p>PURPOSE: To prevent the accuracy deterioration of the temperature distribution measuring owing to the variation of the attenuation factor characteristic of an optical fiber, by removing the effect of the change with the lapse of time in the attenuation factor of the optical fiber, by using the intensity distribution signal of a Rayleigh's rear side scattered light. CONSTITUTION: A signal process and memory controller 9 controls a light source 4 and an optical filter 6, converts the optical filter, and the antiStokes wavelength light, the Stokes wavelength light, and the Rayleigh wavelength light, from the rear side scattered lights b to the light pulses a, are measured about a hundred thousand times, they are D/A converted 8 and averaged, the intensity distribution signals Ia, Is, and IR of the antiStokes Raman scattered light, the Stokes Raman scattered light, and the Rayleigh rear side scattered light are measured and calculated. And the ratio of the distribution signals Ia and Is is found by making the distribution signal IR as the standard, and the temperature distribution on the optical fiber 3 is calculated by using the intensity distributions of the standardized Raman scattered lights. Consequently, the data as to the change with the lapse of time of the attenuation factor of the optical fiber 3 can be removed from the temperature distribution.</p> |
