| 摘要 |
<P>PROBLEM TO BE SOLVED: To reduce influences on eyes of human beings and animals by decreasing the quantity of laser light per unit area while using scattered laser light in the measurement of ground displacement, to perform observation while reducing influences of rain, fog, snow or the like, to ensure safety of workers by promptly performing installation in a location where the occurrence of ground displacement is predicted, and to issue a warning from a warning issuing mechanism when deviation of phases measured by a measuring mechanism exceeds a fixed allowable range. <P>SOLUTION: A warning issuing apparatus comprises a laser light oscillation section 1 which oscillates scattered laser light 4 obtained by enlarging a beam diameter of an irradiation destination rather than a beam diameter of an irradiation source, a laser light reflector 6 which is installed in a location where the occurrence of ground displacement is predicted, a detector 8 which receives a reflection wave 7 to be reflected, a measuring mechanism 11 which measures a distance between the laser light oscillation section 1 and the laser light reflector 6 from deviation of phases between the reflection wave 7 received by the detector 8 and an irradiation wave 10 of the laser light oscillation section 1, and a warning issuing mechanism 14 which issues a warning when the deviation of phases exceeds an allowable range of a reference value in installation. <P>COPYRIGHT: (C)2013,JPO&INPIT |
