| 摘要 |
<p>PROBLEM TO BE SOLVED: To collect observation data of earthquakes at many points of the sea bed at all times or upon necessities. SOLUTION: Optical branching filters 5-1, 5-2 are set at predetermined points of an undersea optical communication cable 4 between ground stations 1 and 2. Seismographs 6-1, 6-2 are respectively connected to the filters 5-1, 5-2. Information is transmitted/received between the seismographs 6-1, 6-2 and ground stations 1, 2 in an optical wavelength multiplication method with the use of light signals of wavelengths assigned for each seismograph.</p> |
