| 摘要 |
<p>An optical branching/synthesizing device (20A) is provided with an optical branching coupler group (25A) and an optical collection unit (26). The optical branching coupler group (25A) includes: a first-stage optical branching coupler (22) for receiving a downstream signal light (Sd) at an optical input-output terminal (22a) from an OLT device (12); and second-stage optical branching couplers (23, 24), optical input-output terminals (23b, 24a) of which are connected to optical input-output terminals (22c, 22d), respectively, of the optical branching coupler (22) of the previous stage. The optical input-output terminals (23a, 23b, 24a, 24b) of the optical branching couplers (23, 24) impart the downstream signal light (Sd) to ONU devices (13) and receive upstream signal light (Su) from the ONU device (13). The optical collection unit (26) collects the upstream signal light (Su) outputted from the optical input/output terminals (22b, 23a, 24b) of the optical branching couplers (22-24).</p> |
