Optical frequency switching appts. with noise elimination - for frequency channel selection in frequency-division multiplexing system, has 2nd order optical non-linear material for wave mixing

摘要

Equipment for optical frequency switching, esp. for selection of frequency channels in optical electronic conversion, includes (a) a material with second-order optical non-linearity for three wave mixing, into which an optical input frequency (Win) and an optical pump frequency (Wp) are introduced and from which a corresp. output frequency (Wout) is extracted, and (d) a device (2) for generating and varying the pump frequency (Wp) within a frequency range. The difference between the variable pump frequency (Wp) and the input frequency (Win) is used as the variable output frequency (Wout). Device (2) is pref. an electrically turnable GaAs laser diode. The optically non-linear material (1) may be LiNb03 crystal (with an applied waveguide structure) or a waveguide of organic polymer material incorporating non-linear optically active chemical substances.