| 摘要 |
PURPOSE:To reduce the cost by detecting an output level of a light emitting element of each optical channel by an optical receiving part of the destination to which an optical transmission is executed, executing the transmission of receiving level information in the lump by electricity or light from the optical receiving part to an optical transmitting part, and correcting the output level of the light emitting element of each optical channel of the optical transmitting part. CONSTITUTION:The respective receiving levels of an optical channel are detected by optical receiving parts 401-404, and receiving level information of each optical channel by detecting the receiving level is multiplexed and transferred by light or electricity to optical transmitting parts 201-204 from the optical receiving parts 401-404. Subsequently, in the optical transmitting parts 201-204, the multiplexed receiving level information is restored, and also, by the receiving level information, a transmitting level of each optical channel is corrected. Accordingly, it is unnecessary to provide an optical output level monitor of a light emitting element of each optical channel on the optical transmitting parts 201-204, and in the optical receiving parts 401-404, in order to observe an actual optical receiving level, an optimum optical transmitting level can be set directly. In such a way, the cost of an automatic optical output controller per an optical channel is reduced. |
