简介：Theoff-planepropagationofelectromagnetic(EM)wavesinatwo-dimensional(2D)graphitephotoniccrystalstructurewasstudiedusingtransfermatrixmethod.Transmissionspectracalculationsindicatethatsucha2Dstructurehasacommonbandgapfrom0.202to0.2035c/aforbothHandEpolarizationsandforalloff-planeanglesform0°upto90°.Thepresenceofsuchanabsolutebandgapimpliesthat2Dgraphitephotoniccrystal,whichismucheasierandmorefeasibletofabricate,canexhibitsomepropertiesofathree-dimensional(3D)photoniccrystal.

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简介：Areal-timetwo-dimensional(2D)triangulationrangefinderispresented,whichiscomposedoftwolinearcomplementarymetaloxidationsemiconductor(CMOS)chips,twocameralenses,andfourlightemittingdiodes(LEDs).Thehighorderdistortioninimageaberrationsisthemainfactorresponsibleforthecoarseerrors.Thetheoreticalpredictionisingoodagreementwithexperimentsandthecorrectionequationisusedtoobtainmorereliableresultswiththeuniquedistortioncoefficientinthewholeworkingregion.

简介：Aphasespacemodeloftwo-dimensional(2D)Gaussianbeampropagationisgeneralizedforthree-dimensional(3D)generalastigmaticGaussianbeampassingthroughfirst-orderopticalsystem.ThegeneralastigmaticGaussianbeamisrepresentedbyafour-dimensional(4D)phasesuper-ellipsoidthatdefinedbyanassociated4×4realmatrix,thenthetransformationformulaofthephasesuper-ellipsoidofthebeamthroughfirst-orderopticalsystemisderived.Inparticular,inthephasespaceframework,thebeampropagationfactorM2valueisprovedtobearatioofphaseareaofrealbeamtoidealbeam,andanovelapproachforaqualitativeexaminationofthepropertiesoffractionalFouriertransform(FRT)forthebeamisalsoprovided.

简介：Therelativebandgapforarhombuslatticephotoniccrystalisstudiedbyplanewaveexpansionmethodandhighfrequencystructuresimulator(HFSS)simulation.GeneralwavevectorsinthefirstBriliouinzonearederived.Therelativebandgapasafunctionofair-fillingfactorandbackgroundmaterialisinvestigated,respectively,andthenatureofphotonicbandgapfordifferentlatticeanglesisanalyzedbythedistributionofelectricenergy.Theseresultswouldprovidetheoreticalinstructionfordesigningopticalintegrateddevicesusingphotoniccrystalwitharhombuslattice.

简介：Basedontheprincipleofspatialpyramidforsignal,amulti-scaletransformoftwo-dimensional(2D)in-terpolatingpyramidisconstructedbythenonlinearmedianoperator.Thetransformpropertiesoferrordiffusehalftoningnoiseonmultiplescalesareinvestigatedandanalyzedthroughexperiments.Accordingtotheseproperties,arobustinversehalftoningmethodisproposed.Thehalftoningimageisfirstlypre-processedbyaGaussianlow-passfilter,anddecomposedbytheone-scaletransform.ThenaWienerfilterisemployedtothedetailedcoefficients.Finallyaninverseimageisreconstructed.Experimentalresultsshowthattheproposedtransformhastheadvantageofseparatingthehalftoningnoiseandimagedetailoverlinearmulti-resolutiontransform.Thepresentedinversehalftoningmethodperformssomeexcellentabilitiesonsharpedge,highpeaksignal-to-noiseratio(PSNR),andsmallmemoryrequirement.

简介：Localizedmodesinone-dimensional(1D)mediawithuniaxialscatterersthatareassumedtobeorderinspatiallocationbutdisorderinspatialorientationoftheiropticalaxisareinvestigated.Basedontheholisticeffectmodelinrandomlaser,i.e.,therandomlaserisduetotheinteractionofthecomplexlocalizedmodesinactiverandommediawithlocalaperiodicquasi-structurewithappropriatepumplight,aphysicalmodelonthistypeofrandommediaisfound.ItsdisorderdegreeisdefinedbyD=n_o/n_e.Then,thetypicaltransmissionspectrumthroughtherandommediaandthelightfieldintensitydistributioncorrespondingtothedefectmodesinphotonicband-gaparecalculatednumericallybymeansofthetransfermatrixmethod,andtheconditionthatthelocalizedmodeappearsisdiscussed.Resultsshowthatthemediumdisorderplaysanimportantroleindeterminingthelightwavestate.Thelocalizedstateappearswhenthemediumdisorderisstrongenough,andanewmechanismcreatingrandomlaserphenomenonisbroughtforward.

简介：Lightextractionefficiencyoforganiclightemittingdiode(OLED)basedonvariousphotoniccrystalslab(PCS)structureswasstudied.Byusingthefinite-differencetime-domain(FDTD)method,weinvestigatedtheeffectofseveralparameters,includingfillingfactorandlatticeconstant,ontheenhancementoflightextractionefficiencyofthreebasicPCSs,andgotthemosteffectiveone.Twonoveldesignsof'interlaced'and'double-interlaced'PCSstructuresbasedonthemosteffectivebasicPCSstructurewereintroduced,andthe'interlaced'onewasprovedtobeevenmoreefficientthanitsprototype.Largeenhancementoflightextractionefficiencyresultedfromthecouplingtoleakymodesintheexpendedlightconeofabandstructure,thediffractioninthespacebetweencolumns,aswellasthestrongscatteringatindium-tin-oxide/glassinterfaces.

简介：Bystudyingthethermal-inducedphaseshiftmechanismofaninterferometricfiber-opticgyroscope(IFOG)sensingcoil,anovelgeneralizedexpressionbasedonathree-dimensional(3D)modelisproposed.ComparedwiththetraditionalpureShupeeffectmodel,thesimulationresultsshowthatthenew3Dmodel,includingelasticstrainandtheelasto-opticaleffect,candescribethethermaleffectofthecoilsmoreaccurately.Experimentswithtemperaturechangeratesbetween-40°Cand70°Careperformedtoverifytheeffectivenessoftheproposedgeneralizedexpression.Theresultsofourworkcanguideresearchersinidentifyingcountermeasurestoreducethethermal-inducedbiaserrorinIFOG.

简介：Weproposesomenewschemestoconstitutetwo-dimensional(2D)arrayofmulti-wellopticaldipoletrapsforcoldatoms(ormolecules)byusinganopticalsystemconsistingofabinaryπ-phasegratinganda2Darrayofrectanglemicrolens.Wecalculatetheintensitydistributionofeachopticalwellin2Darrayofmulti-welltrapsanditsgeometricparametersandsoon.Theproposed2Darrayofmulti-welltrapscanbeusedtoformnovel2Dopticallatticeswithcoldatoms(ormolecules),andformvariousnovelopticalcrystalswithcoldatoms(ormolecules),ortoperformquantumcomputingandquantuminformationprocessingonanatomchip,eventorealizeanarrayofall-opticalmulti-wellatomic(ormolecular)Bose-Einsteincondensates(BECs)onanall-opticalintegratedatom(ormolecule)chip.

简介：Two-photonphotopolymerization(TPP)withfemtosecondlaserisapromisingmethodtofabricatethree-dimensional(3D)photoniccrystals(PCs).BasedontheTPPprinciple,themicro-fabricationsystemhasbeenbuilt.The3DwoodpilePCswithrodspaceof2000nmarefabricatedeasilyanddifferentdefectsareintroducedinordertoformthecross-waveguideandthemicro-laserstructurePCs.Simulationresultsoftheopticalfieldintensitydistributionsusingfinite-differencetimedomain(FDTD)methodaregiven,whichsupportthedesignsandimplementationofthePCoftwotypesintheory.

简介：Two-dimensionalmetallicphotoniccrystalslabswithsquarelatticeareproposedtobeusedforthedesignofwaveguidebandpassfiltersoperatinginmillimetertoterahertzregion.Filtercharacteristicsarestudiedwhenrodradiiandlatticeconstantsarechanged.Basedonthefrequencyscalingtechnique,aseriesofhigherfrequencyfiltershasbeendesigned.Byusinglaserdrillingandweldingprocessingtechniques,acompactwaveguidefilterembeddedinanEIA-WR10waveguidewithcentralfrequency145.5GHzand3-dBbandwidthof5.26GHzisfabricatedandmeasured.Themeasurementdataagreewellwiththesimulationprediction.

简介：Twodifferentmethodsfromgraphicprocessingunit(GPU)andcentralprocessingunit(CPU)areproposedtosuitablyoptimizelook-uptablealgorithmsofcomputergeneratedholography(CGH).Thenumericalsimulationsandexperimentalresultsshowthatwecanreconstructagoodqualityobject.ThecomputationofCGHforathree-dimensional(3D)dynamicholographicdisplaycanalsobespedupbyprogrammingwithourproposedmethod.Itcanoptimizebothfileloadingandtheinlinecalculationprocess.Thephase-onlyCGHwithgigabytedataforreconstructing10MBobjectsamplingsisgenerated.Inaddition,theproposedmethodeffectivelyreducedtimecostsofloadingandwritingofflinetablesonaCPU.ItisbelievedtheproposedmethodcanprovidehighspeedandhugedataCGHfor3Ddynamicholographicdisplaysinthenearfuture.

简介：Wereportontherichdynamicsoftwo-dimensionalfundamentalsolitonscoupledandinteractingonthetopofanellipticalshapedpotentialinatwo-dimensionalGinzburg–Landaumodel.Undertheellipticalshapedpotential,thesolitonsdisplayuniqueanddynamicproperties,suchasthegenerationofstraight-linearrays,emissionofeitheroneellipticalshapedsolitonorseveralellipticalringsolitonarrays,andsolitondecay.Whenchangingthedepthandsharpnessoftheexternalpotentialandfixingotherparametersofthepotential,variousscenariosofsolitondynamicsarealsorevealed.Theseresultssuggestsomepossibleapplicationsforall-opticaldata-processingschemes,suchastheroutingoflightsignalsinopticalcommunicationdevices.

简介：Thetransmissionpropertiesofone-dimensionalphotoniccrystalscontainingdouble-negativeandsingle-negativematerialsarestudiedtheoretically.Aspecialkindofphotonicbandgapisfoundinthisstructure.Thisgapisinvariantwithscalingandinsensitivetothicknessfluctuation.Butwhenchangingtheratioofthethicknessoftwomedia,thewidthofthegapcouldbeenlarged.Thedefectmodesareanalyzedbyinducingalineardefectlayerinthestructure.Itisfoundthatthenumberofdefectmodeswillincreasewhenthethicknessofthedefectlayerbecomeslarger.更多还原

简介：Atwo-dimensional(2D)opticaltrue-timedelay(TTD)beam-formingsystemusingacompactfibergratingprism(FGP)foraplanarphasedarrayantenna(PAA)isproposed.Theopticalbeam-formingsystemmainlyconsistsofaTTDunitbasedonthesamecompactFGP,onetunablelaserforelevationbeamsteering,andacontrolledwavelengthconverterforazimuthbeamsteering.AplanarPAAusingsuch2DopticalTTDunithasadvantagessuchascompactness,lowbandwidthrequirementfortunablelasersources,andpotentialforlarge-scalesystemimplementations.Theproof-of-conceptexperimentresultsdemonstratethefeasibilityoftheproposedscheme.

简介：Amethodtothree-dimensionalpositionmovingparticleswithonelensandtwocamerasisproposed.Twoparticleimageswithdifferentdegreesofdefocusingareadoptedtosolvetheambiguousproblemofparticlepositions.Asingle-lensdual-camerasystemisdevelopedtosimultaneouslycapturethesetwoimagesforthemovingparticles.Themeasurementprinciplesandtheoreticalanalysisareintroducedfirst,andthensimulatedinvestigationsandexperimentalresearcharediscussed.Themeasurementerrorsinthesimulationsandexperimentsarelessthan1%and4%,respectively,in20timesthedepthoffieldofthesystem,whichvalidatesthefeasibilityofthismethod.