Abstract:Adiscollimatedopticalfeedbackconfigurationofgratingexternalcavitysemiconductorlaserhasbeenexperimentallyproposedwithcharacteristicsofstableoutputandwidetuningrange.Theeffectivenessofconfigurationhasbeenverifiedatwavelengthof1.55mand1.31mrespectively.Acontinuoustuningrangegreaterthan216GHz,asidemodesuppressionratioabove30dBandtunablerangeof80nmhasbeenachievedwhentheresidualreflectivityatthelaserchipARcoatedfacetfacingtheexternalcavityisabout3%.Itsspectrallinewidthwas50kHzandtheoutputstabilityisremarkablyenhancedcomparingwithcollimatedopticalfeedback.