Optical transmission line joint supervisory mode

摘要

PURPOSE:To detect the connection or disconnection between an optical transmitting device and an external optical transmission line and also to enable the control of transmission, stop of transmission, etc., of the optical data. CONSTITUTION:When the optical signals having the components of wavelengths lambda1 and lambda2 are outputted to an optical connector 30 from a light emitting element for transmission use 21 through an optical fiber cable 23. Thus an optical connector 40 containing a band pass filter lets the optical signal of the wavelength lambda1 transmit and lets the optical signal of the wavelength lambda2 reflect respectively. In a disconnection state of the connector 40, the optical signal of the wavelength lambda2 is not received by a monitoring light receiving element for monitoring use 22. The output current showing the receiving states of both optical signals of wavelength lambda1, lambda2 is converted into the voltage by a current/voltage converter 50. This voltage is compared with the reference voltage 13 by a voltage comparator 60 for detection of the connection or disconnection of an optical fiber cable 42.