BIDIRECTIONAL OPTICAL FIBER TRANSMISSION SYSTEM

摘要

A bidirectional optical fiber transmission system is disclosed. Two transmitter-receiver sets are interconnected by an optical fiber and each set includes a light emitting diode (l.e.d.) transmitter, a light receiver and circuitry for mutually isolating transmitted and received light. The emission spectra of the l.e.d.'s should be identical or overlapping and the isolating circuitry in each set comprises a short wave pass filter and a non-overlapping long wave pass filter. An optical directional coupler or light divider is used to couple the transmitting and receiving sides to the optical fiber. The sensitivity of reception can be improved over the prior art because the attentuation of near-end leakage to each receiver is greatly increased.