High data transmission rate optical converter for digital data links - has auxiliary converter providing polarisation independent wavelength coupled level dependent synchronised oscillator returning auxiliary wavelength

摘要

The optical converter has an input modulated waveform (E) at a first wavelength. The optical input is coupled (C) to an auxiliary converter (1). The auxiliary convertor gives a modulated signal (M) in phase opposition to the input, and independent of polarization, having a second wavelength. The output from the auxiliary converter is coupled to a synchronised oscillator (2). If the auxiliary wavelength signal exceeds a threshold level, the auxiliary wavelength is returned, otherwise the output wavelength response is returned. In either case the output response is coupled to a fourth port and the output signal (S) produced.