简介:ApyrotechnicallypumpedNdglasslaserisdemonstratedbytheuseofpyrotechnicflashlampscomposedofseveralchemicalmaterialsarrangedinastableplaneconcaveresonatorcavity.Theflashlampwasmadeofchemicalmixturewithoxidant,fuel,andbinder.TheemissionspectrumofpyrotechnicflamecoveredmostoftheabsorptionbandsofNd~(3+)inphosphateglass.Under4.56-gchemicalmixturepumping,longpulseoutputpowerofabout5.5Wwasachieved.
简介:Theoreticalanalysisoftheelectromagneticfielddistributioninthefocalregionofalongmetallicparabolicreflectorthathasitssurfacecoveredwithamagnetizedplasmalayerisderived.Theincidentwaveisconsideredtobewithageneralobliqueincidenceforbothparallelandperpendicularpolarizations.TheelectromagneticfieldintensityexpressionsalongthefocalregionareobtainedaccuratelyusingMaslov’smethod.Theeffectsofplasmathicknessonthereflectedandtransmittedfielddistributionsareinvestigated.Theeffectsofotherphysicalparameterssuchastheangleofincidenceandtheplasmaandcyclotronfrequenciesonthetransmittedfieldintensitydistributionalongthefocalregionarealsostudied.TheresultsobtainedbyMaslov’smethodandKirchhoff’sapproximationarefoundtobeinagoodagreement.
简介:Real-timevideostreamingusingultra-wideband(UWB)technologyisexperimentallydemonstratedalonglong-reachpassiveopticalnetworks(LR-PONs)withdifferentwiredandwirelessreaches.ExperimentaltestsusingexternalanddirectmodulationwithUWBwirelessradiationinthe10-and60-GHzbandsareperformed.Anultra-bendablefiberisalsoconsideredforalast-miledistribution.ThevideoqualityattheoutputoftheopticalfiberinfrastructureoftheLR-PONisassessedusingtheerrorvectormagnitude(EVM),andthelinkqualityindicator(LQI)isusedasafigureofmeritafterwirelessradiation.AnEVMbelow–17dBisachievedforbothexternallyanddirectlymodulatedLR-PONscomprisingupto125kmofopticalfiber.EVMimprovementisobservedforlongerLR-PONswhendirectlymodulatedlasers(DMLs)areusedbecauseoftheamplitudegainprovidedbythecombinedeffectofdispersionandDML’schirp.Comparedwithopticalback-to-backoperation,theLQIleveldegradestothemaximumaround20%forLR-PONsrangingbetween75and125kmoffiberreachandwithawirelesscoverageof2minthe10-GHzUWBband.ThesamelevelofLQIdegradationisobservedusingthe60-GHzUWBbandwithaLR-PONintegrating101kmofaccessnetwork,alast-miledistributionusingultra-bendablefiber,anda5.2-mwirelesslink.