data for optical hybrid

The optical hybrid is mainly used to split and combine the signal beam and the local oscillator beam from two inputs, thereby generating four mixed beams with a relative phase difference of 90°. 90º optical hybrid is suitable for coherent signal demodulation for either homodyne or heterodyne detection. The device accepts the two optical signals (S & L) and generates four output signals: S+L, S-L, S+jL, and S-jL. When these signals are detected by two balanced receivers, both the amplitude and the relative phase information between the input signals can be extracted via differential detection and digital signal processing.