Title:
DETECTING EQUIPMENT FOR LANDSLIDE
Document Type and Number:
Japanese Patent JP2585169
Kind Code:
B2
Abstract:
PURPOSE: To detect a landslide automatically and to enable execution of monitoring in a wide range by laying optical fibers in a monitoring place and by catching a change of light propagated through the optical fibers.
CONSTITUTION: A light 1' and a light 2' emitted from a first light source 1 of high coherence and a second light source 2 of low coherence respectively are synthesized to be superposed mutually by a synthesizer 3 and made to enter a photocoupler 4. By the characteristics of the coupler 4, the light 1' is made to branch by 50% for both of optical fibers 5A and 5B connected onto the output side of the coupler while the light 2' is outputted to the fiber 5A. A light interference detector 7 monitors mutual changes of phases of the lights 1' propagated through the fibers 5A and 5B. Thereby, a slight change of the configuration of the ground before a landslide can be caught. Out of other output lights 1' and 2' of a photocoupler 6, only the light 2' is divided to be taken out by a wave divider 8 and given to a loss detector 9, which monitors a change in the amount of arrival of the light 2'. When the rate of arrival of the light 2' propagated through the fiber 5A or 5B lowers, the detector 9 detects an increase of a loss and can give information on occurrence of the landslide.
More Like This:
Inventors:
SASAKI HIROYUKI
OONO ARITAKA
KABARU TATSUO
MOTOHARA SHINJI
AIHARA SHUICHI
KOSAKA JUZO
UJIGAWA MASAAKI
OONO ARITAKA
KABARU TATSUO
MOTOHARA SHINJI
AIHARA SHUICHI
KOSAKA JUZO
UJIGAWA MASAAKI
Application Number:
JP23491392A
Publication Date:
February 26, 1997
Filing Date:
September 02, 1992
Export Citation:
Assignee:
JAPAN AVIATION ELECTRON
International Classes:
G01D21/00; G01D5/26; G01D5/353; G02B6/00; (IPC1-7): G01D21/00; G01D5/26; G02B6/00
Domestic Patent References:
| JP480618A | ||||
| JP2242119A |
Attorney, Agent or Firm:
Kusano Taku (1 person outside)