BIDIRECTIONAL OPTICAL COMMUNICATION EQUIPMENT

PURPOSE:To increase the number of connection terminal equipments and to prevent the effect on plural terminal equipments due to the disconnection transmission line fiber by connecting a central station with each terminal equipment via an optical branching coupler of N:M in a bidirectional optical communication equipment distributing a signal from the central station to each terminal equipment and collecting a signal from each terminal equipment to the central station. CONSTITUTION:An optical branching coupler D whose input/output terminal number is, e.g., 1:N is used. An optical signal sent from the central station 1 is inputted to the optical branching coupler D through an optical fiber B1, branched uniformly to N-line of optical fibers C2...Cn connected to the output terminal and outputted to terminal equipments 2...n. Then the optical signal sent from the terminal equipments 2...n is inputted to the optical branching coupler D through the optical fibers C2...Cn, synthesized and outputted to the central station 1 by the optical fiber B1. When the transmission signal from the terminal equipments 2...n is received by the central station 1 by the operation of polling or the like so as to avoid from being overlapped, then the central station 1 receives them as independent signals.