Title:
MONITORING METHOD FOR TEMPERATURE OF LIQUEFIED GAS TANK
Document Type and Number:
Japanese Patent JPS63138225
Kind Code:
A
Abstract:
PURPOSE:To monitor a temperature distribution by providing an optical fiber cable which has mixed impurities by which a characteristic of a photoabsorption band peculiar to a substance is varied by a temperature, on a liquefied gas tank, and detecting a back raly scattered light of an incident optical pulse. CONSTITUTION:As for a fiber cable 11 for measuring a temperature, a rare earth element ion is doped in a core part and a clad part made of high purity quartz glass, said cable has an intrinsic absorption peak based on each element ion, extending from a visible area to an infrared area, and an absorption quantity of light is varied by a temperature. The cable 11 is wound to a liquefied gas tank 10 being an object to be measured, and light is inputted by a pulse. An intensity against an input optical pulse of an optical pulse which is returned by back Rayleigh scattering in the cable 11 and a value of time are photodetected by a photodetector 43 through a half mirror 42 placed between an input use laser 41 and a fiber incident end 40, and a position of a hot zone in the tank 10 and its temperature can be measured.
Inventors:
NAKAMURA KAZUNORI
KATSUYAMA YOSHIHISA
KATSUYAMA YOSHIHISA
Application Number:
JP28487186A
Publication Date:
June 10, 1988
Filing Date:
November 29, 1986
Export Citation:
Assignee:
FURUKAWA ELECTRIC CO LTD
International Classes:
G01K11/12; C03C13/04; F17C13/02; G02B6/00; (IPC1-7): C03C13/04; F17C13/02; G01K11/12; G02B6/00
Domestic Patent References:
| JPS60152926A | 1985-08-12 |
Attorney, Agent or Firm:
Shoji Kobayashi