简介：Eccentricphoto-refractionusuallyisusedasearlyeyesightdiagnostictestofinfantsandsmallchildren.Unlikecurrentlyapprovedgeometricalopticalmodelofeccentricphotorefractometer,thecrescentformationandthelight-intensitydistributioninthepupilimageofamyopiceyeareanalyzedbyFourieropticswiththeassumptionofanisotropicscatteringretina.Inthecaseoflittlecircularlightsourceandrectangularslit,thesimulationresultsofdifferentmyopicdioptersareobtainedbygeometricalopticaltheoryandFourieropticsrespectively.ItisfoundthatthesimulationresultsbyFourieropticsaresimilarasthoseobtainedbygeometricaloptics,andallsimulationsarealmostcorrespondingtotheexperimentalresult.Theresultdemonstratesthatthenewmethodpresentedhereisfeasible.

简介：Thebasicideaofthefiniteelementbeampropagationmethod(FE-BPM)isdescribed.Itisappliedtocalculatethefundamentalmodeofachannelplasmonicpolariton(CPP)waveguidetoconfirmitsvalidity.Boththefielddistributionandtheeffectiveindexofthefundamentalmodearegivenbythemethod.Theconvergencespeedshowstheadvantageandstabilityofthismethod.Thenaplasmonicwaveguidewithadielectricstripdepositedonametalsubstrateisinvestigated,andthegroupvelocityisnegativeforthefundamentalmodeofthiskindofwaveguide.Thenumericalresultshowsthatthepowerflowdirectionisreversetothatofphasevelocity.

简介：Asimplifiedmodalmethodtoexplaintheresonancephenomenoninguidedmoderesonance(GMR)gratingswithasymmetriccoatingsispresented.Theresonanceobservedisduetotheinteractionoftwopropagationmodesinsidethegrating.Thereflectivityspectraandelectricfielddistributionscalculatedfromthesimplifiedmodalmethodarecomparedusingrigorouscoupled-waveanalysis(RCWA).Theinfluencesofhigh-orderevanescentmodesontheresonancepeakareanalyzed.AmatrixFabry-Perot(FP)resonanceconditionisdevelopedtoevaluatetheresonancewavelength.AnexplanationfortheresonancephenomenonobservedbasedontheFPresonancephaseconditionisalsoproposedanddemonstrated.ThesimplifiedmethodprovidesclearphysicalinsightsintoGMRgratingsthatareusefulfortheanalysisofavarietyofotherresonancegratings.

简介：Quantumkeydistribution(QKD)isamajorresearchtopicbecauseitprovidesunconditionalsecurity.Unfortunately,manyimperfectionsremaininQKD’sexperimentalrealization.TheFaraday–Michelson(FM)QKDsystemisproposedtoeliminatetheseimperfectionsusingpolarization.However,thelongarm’sphasemodulator(PM)hasanunexpectedinsertionloss,meaningthatthestatesentisnolongerperfect.Inthisletter,weproposeanalternativeFM-QKDsystemstructure,andanalyzethesecurityandkeygenerationrateincomparisonwiththeoriginalsystemviadifferentanalysismethods.WefindanobviouskeyrateimprovementwhenthePMinsertionlossisnotextremelysmall.

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

简介：Apavementreflectancemeasurementsystemisestablishedbasedonagonio-photometerexistingbychangingabrackettocarrytheroadsampleandluminancemeter,addingacollimatedlightsourcetoprovideincidentlight.Thisautomatedsystemcouldfinishthereflectionmeasurementofaroadsamplein4h.AnuncertaintybudgetofthismeasurementsystemismadeandthecombinedstandarduncertaintyofQ0is5.26%.

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

简介：Thefingerjointlinesdefinedasfingercreasesanditsdistributioncanidentifyaperson.Inthispaper,weproposeanewfingercreasepatternrecognitionmethodbasedonLegendremomentsandprincipalcomponentanalysis(PCA).Afterobtainingtheregionofinterest(ROI)foreachfingerimageinthepreprocessingstage,LegendremomentsunderRadontransformareappliedtoconstructamomentfeaturematrixfromtheROI,whichgreatlydecreasesthedimensionalityofROIandcanrepresentprincipalcomponentsofthefingercreasesquitewell.Then,anapproachtofingercreasepatternrecognitionisdesignedbasedonKarhunen-Loeve(K-L)transform.ThemethodappliesPCAtoamomentfeaturematrixratherthantheoriginalimagematrixtoachievethefeaturevector.Theproposedmethodhasbeentestedonadatabaseof824imagesfrom103individualsusingthenearestneighborclassifier.Theaccuracyupto98.584%hasbeenobtainedwhenusing4samplesperclassfortraining.Theexperimentalresultsdemonstratethatourproposedapproachisfeasibleandeffectiveinbiometrics.

简介：Scalefactorofaconstantratebiasedringlasergyro(RLG)isstudiedboththeoreticallyandexperimentally.Byanalyzingexperimentaldata,wefindthattherearethreemaintermscontributingtothescalefactordeviation.Oneofthemisindependentoftime,thesecondvarieslinearlywithtimeandthethirdvariesexponentiallywithtime.Theoreticalanalysesshowthatthefirsttermiscausedbyexperimentalsetup,thesecondandthethirdarecausedbyun-uniformthermalexpensionandcavitylossvariationoftheRLG.

简介：Thereappeartobethreeprincipleforcesdrivingthefutureofnewdrugdevelopment:under-standingthegenome-transcrip-tome-protemecorrelations,under-standingandmappingproteinposttrans-lationalmodification(PTM)pathways,andintegrationofmassspectrometry(MS)techniquesintoroutineproteinidentificationandcharacterization.

简介：我们表明电的敲击笔记分析和一个连续波浪(cw)锁在3THz(100m)附近射出的兆兆赫量串联激光(QCL)的收音机频率(RF)注射。在免费的跑，QCL的敲击笔记频率与增加开车电流显示出180MHz的移动。敲击笔记，调整反应，拉的注射，和兆兆赫排放光谱在不同当前的政体的特征我，II，和III被调查。结果证明在我关上到激光阀值的当前的政体，我们在洞双程票频率获得RF调整的更狭窄的敲击笔记和扁平的反应。拉的效果并且光谱调整大小在当前的政体验证那我锁住的RF注射是有效的更多和一个柔韧的工具调制模式数字和兆兆赫QCL的模式频率。

简介：Influenceofthermal-mechanicalpropertiesonthefeaturesofthepandapolarization-maintainingopticalfiber(PMF)infabricationprocessisstudiedindetailbyfiniteelementmethod(FEM).Thestressbirefringenceis2.13443×10-4obtainedbythestaticanalysisand2.1269×10-4bydynamicanalysis.Thedifferenceinsimulationbytwomethodsisaround0.4%.Thenon-uniformityofstressbirefringenceinthefibercoreisabout1.6%.Predictedresultsdemonstratethateffectofthethermalconductiveparameteronfiberthermalstressdominates.Thehighanduniformstressbirefringenceinthefibercoreisobtainedbyappropriatelyselectingsuitablestressregionareaandposition.

简介：Anumericaldesignonthetriangularphotoniccrystalfiber(PCF)basedbackwardmulti-pumpRamanamplifierispresented.ItisdemonstratedthathighflatRamangaincanbereachedbasedonPCF.InfluencesofdifferentgeometricparametersandgermaniumdopingconcentrationsontheRamannetgain,amplifiedspontaneousemission(ASE)noiseanddoubleRayleighbackscattering(DRBS)ofthesignalhavebeenanalyzed.ForoptimizingcrystalfiberRamanamplifier(FRA),thereistradeoffbetweenthegeometricparameterandgermaniumdopingconcentrationoftriangularPCF.TheresultsshowthatPCFisanappropriatecandidateforhighgainRamanamplifiers.

简介：WeinvestigatethelateralshiftofaTM-polarizedlightbeamreflectedfromOttoconfigurationundergrazingincidence.Itisfoundthatthelateralshiftisstronglydependentonthethicknessoftheair-gaplayer.Byemployingthepole-nullrepresentation,wedemonstratethatthelateralshiftiscloselyrelatedtothenullofthereflectionfunction.ThenumericalsimulationsforaGaussianbeamareperformedtodemonstratethevalidityofourtheoreticalanalysis.

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简介：WhenfemtosecondlaserpulsesinterferewithchirpedfemtosecondlaserpulsesinAs2S3fiber,achirpedfibergratingisformed.Ananalyticalexpressionisgiventodescribethechirpedgrating,anditsBraggreflectivityiscalculated.BecauseofthehighphotosensitiveeffectofAs2S3material,thechirpedfibergratinghasawideBraggreflectivespectrumandhighreflectivitybychoosingproperparameters.Thisindicatesthatthechirpedfibergratingcanbeusedasastretcherinthefemtosecondchirpedpulseamplification(CPA)system.

简介：Thereisatradeoffbetweenthequantumefficiencyandthespectralresponselinewidthinresonant-cavityenhanced(RCE)photodetectors.Recentlyanewtypeofphotodetectorstructurehasbeenproposed,whichutilizesaninclinedmirrorinathree-mirrorcavity.Itdecouplesthequantumefficiencyandthespectralresponselinewidthandhashighresponsespeed,highquantumefficiency,andnarrowlinewidthsimultaneously.Theanalysisresultindicatesthatthelinewidthof0.8nmandquantumefficiencyhigherthan70%canbeachievedonthisdevice.Fora30×30μm2device,themaximumbandwidthapproaches23GHz.

简介：Wereportthedirectfabricationofamicrofluidicchipcomposedoftwohigh-aspectratiomicrofluidicchannelswithlengthsof3.5cmand8mminaglasssubstratebyfemtosecondlasermicromachining.Thefabricationmainlyconsistsoftwosteps:1)writingmicrochannelsandmicrochambersinaporousglassbyscanningatightlyfocusedlaserbeam;2)high-temperatureannealingoftheglasssampletocollapseallthenanoporesintheglass.Migrationofderivatizedaminoacidsisobservedinthemicrofluidicchannelbyapplyingelectricvoltageacrossthelong-migrationmicrochannel.

简介：Anoptimalpowerdistributionanalysisforanall-opticalsamplingorthagonalfrequencydivisionmultiplexing(OFDM)schemewithmultiplemodulationformatsincludingdiferentialphaseshiftkeyed(DPSK),diferentialquadraturephaseshiftkeyed(DQPSK),andnon-return-to-zero(NRZ)isproposed.Thenoisetolerancesofdifferentmodulationformatsareanalyzed,andtheoptimalinputpowerratiobetweenphaseandintensitymodulationformatsforthebestoverallreceivingperformanceisinvestigatedunderunchangedtotalinputpower.Moreover,thisschemecanseamlesslycoexistwiththetraditionalWDMchannel.

简介：Photoniccrystalfibers(PCFs)withasteppedraised-coreprofileandonelayerequallyspacedholesinthecladdingareanalyzed.Usingeffectiveindexmethodandconsideringaraisedsteprefractiveindexdifferencebetweentheindexofthecoreandtheeffectiveindexofthecladding,weimprovethecharacteristicparameterssuchasnumericalapertureandV-parameter,andreduceitsbendinglosstoaboutonetenthofaconventionalPCF.ImplementingsuchastructureinPCFsmaybeonestepforwardtoachievelowlossPCFsforcommunicationapplications.