| 摘要 |
PURPOSE:To eliminate turbulence of a spectrum by repeating and to allow long distance optical transmission by controlling an optical switch of a laser light source of a constant-current drive by an electrical signal of a photodetector, which is digital-processed. CONSTITUTION:A photodetector 3, which is coupled to a coupling means 1 of a digital optical signal transmission line, converts a digital optical signal into an electrical signal. An optical switch 21 switches laser light of a laser light source 5 driven by a constant-current. Moreover, a digital signal processor 20 digital- processes the electrical signal obtained by the photodetector 3 and controls the switch 21. Therefore, there is no turbulence of a spectrum due to repeating. On the contrary, the signal is improved, and therefore not only long distance optical transmission but also signal monitoring at a repeating point are available. |
