TheAgilent11980AisaMach-Zehnderinterferometeroffixeddelay.UsedwithanAgilent71400seriesorAgilent83810Blightw***esignalanalyzer,itallowsyoutomeasurechirpandfrequencymodulation(FM)onDFBlasers.Traditionalmeasurementsoflaserlinewidthonsingle-linelaserscanalsobemade.)