| 摘要 |
PURPOSE:To facilitate the correct diagnosis of the presence or absence of the disconnection of an optical cable by detecting whether the power source of the present optical communication device is on or off and providing a optical switch for switching the looping of the other optical signal transmission side transmission path or the connecting thereof to the present optical signal reception section according to the result of this detection. CONSTITUTION:The optical switch 3 shifts to a switch contact side shown by a solid line if a power source is off. The light signal past the optical cable 8 passes an optical connector and is looped back by the optical switch 3 and is returned through an optical coupler 4 and an optical connector 7 to the other optical communication device. The optical 3 shifts to the switch contact side shown by a broken line if the power source is on. The light signal past the optical cable 8 is then inputted through the optical connector 7 and the optical switch 3 to an optical signal reception section 5. The light signal outputted from the optical signal reception section 6 is outputted through the optical coupler 4 and the optical connector 7 to the optical cable 8. Then, the light signal from the other optical communication device is looped back even if the power source is uncharged and, therefore, the detection with the other optical communication device is possible and the optical cable is recognized to be not disconnected. Whether the optical cable is disconnected or not is correctly detected in this way. |
