简介：Thenormalspectralemissivityofniobiumstripspecimenismeasuredusinganewpulse-heatingreflectometrictechnique.Thehemisphericalspectralreflectivityofthesurfaceofastriptangenttoanintegratingsphereisdeterminedbyahigh-speedlock-intechnique.Atthesametime,theradiancetem-peratureofthestripismeasuredbythemulti-wavelengthhigh-speedpyrometerfromapproximately1000Ktothemeltingpoint.Detailsofthemeasurementmethodandoftherelatedcalibrationtechniquesarereported.Resultsofthenormalspectralemissivityofniobiumat633,753,827,and905nmfromroomtemperaturetoitsmeltingpointarepresented.Theaccuracyofspectralemissivitiesisestimatedbetterthan5%.

简介：Inthispaper,wederivethebrightanddarkphotonnumberstatesforspatialinterferenceoftwoormorelightbeamsandsucceedintheexplanationofYoung'sinterferenceexperiment,andalsoachieveabettercomprehensionofthewellknowncommentofDirac"eachphotononlyinterferenceswithitself".Fromthefullyquantumpointofview,theoriginoftheinterferencefringesconsistsinthemodetransformationandthedetectionofdouble-slitstates.

简介：提出了基于K-means聚类和SPIHT编码的红外图像压缩算法。通过采用小波域系数的SPIHT编码压缩，克服了JPEG标准压缩算法在低比特率下严重的方块效应；通过K-means聚类算法，克服了嵌入式零树编码算法（EZW）没有充分考虑到图像小波系数同一子带中相邻元素之间相关性的缺陷。实验结果表明，此算法对红外图像具有很好的边缘和纹理保持性能。

简介：利用有限元法对脉冲CO2激光辐照K9玻璃样品中的温度和应力分布进行了数值分析。对半径为20mm、厚为2mm的圆盘样品的计算结果表明，K9玻璃的损伤由环向应力控制，体损伤先于面损伤产生，且光斑半径和脉冲数目对损伤闽值有较大的影响，在激光光斑半径为5mm，脉宽为10肛s的条件下K9玻璃的单脉冲CO2激光的损伤闽值为0．5J，相应的能量密度为0．637J／cm^2。损伤闽值随光斑半径的增大而增大，随脉冲数目的增加而变小。讨论了样品半径和厚度对损伤结果的影响，结果表明样品半径在10-20mm范围内所产生的拉伸应力较小。

简介：Anexperimentofadaptivepolarizationmodedispersion(PMD)compensationfor40-Gb/sreturn-to-zero(RZ)opticalcommunicationsystemisreported.Intheexperiment,degreeofpolarization(DOP)isusedasfeedbacksignalandparticleswarmoptimization(PSO)methodisadoptedaslogiccontrolalgorithm.Thecompensationtimeisabout200ms,thecompensateddifferentialgroupdelay(DGD)isupto30ps,andbiterrorrate(BER)of10^-9isreachedwhenPMDcompensationisemployed.

简介：通过把脉宽为lOns、波长为1064nm的激光脉冲聚焦通过K9玻璃的方法，研究了玻璃的损伤形貌特点与高强度纳秒激光脉冲的关系。当激光脉？中聚焦在样品中心时，产生的破坏点的特点为前端大，后端小，并且纵向出现裂纹，使用高强度激光与物质相互作用时产生的激光支持的爆轰波特点解释了这些破坏特点。当激光脉冲聚焦在样品表面时，产生的破坏特点是串状的，即带有点状破坏的丝状破坏，这是由于内部缺陷或颗粒和动态自聚焦作用的结果。

简介：Anewscreen-spotimagingmethodbasedonopticalmeasurementisproposed,whichisapplicabletotheclose-rangemeasurementofaircraft'sthree-dimensional(3D)attitudeparameters.Lasertrackerisusedtofinishtheglobalcalibrationsofthehigh-speedcamerasandthefixedscreensontestsite,aswellastoestablishmedia-coordinate-framesamongvariouscoordinatesystems.Thelasercooperationobjectmountedontheaircraftsurfaceprojectslaserbeamsonthescreensandthehigh-speedcamerassyn-chronouslyrecordthelight-spots'positionchangingwithaircraftattitude.Therecordedimagesequencesareusedtocomputetheaircraftattitudeparameters.Basedonthematrixanalysis,theerrorsourcesofthemeasurementaccuracyareanalyzed,andthemaximumrelativeerrorofthismathematicalmodelisestimated.Theexperimentalresultshowsthatthismethodeffectivelymakesthechangeofaircraftpositiondistinguishable,andtheerrorofthismethodisnomorethan3′whiletherotationanglesofthreeaxesarewithinacertainrange.

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

简介：ByusingPDM-OFDM-16QAMmodulation,all-Ramanamplification,coherentdetection,and7%forwarderrorcorrection(FEC)threshold,wesuccessfullydemonstrate63-Tb/s(368×183.3-Gb/s)signalover160-kmstandardsinglemodefiber(SSMF)transmissionintheC-andL-bandswith25-GHzchannelspacing.368opticalchannelswithbandwidthspacingof25GHzaregeneratedfrom16externalcavitylasersources.After160-kmSSMFtransmission,alltestedbiterrorrate(BER)areunder3.8×10-3,whichcanberecoveredby7%FECthreshold.Withineachchannel,weachievethespectralefficiencyof6.85bit/s/HzinC/Lband.

简介：Aquasi-cycliclow-densityparitycheck(QC-LDPC)codeisconstructedbyanimp

简介：Weexperimentallydemonstrateall-opticalclockrecoveryfor100Gb/sreturn-to-zeroon–offkeyingsignalsbasedonamonolithicdual-modedistributedBraggreflector(DBR)laser,whichcanrealizebothmodespacingandwavelengthtuning.Byusingacoherentinjectionlockingscheme,a100GHzopticalclockcanberecoveredwithatimingjitterof530fs,whichisderivedbyanopticalsamplingoscilloscopefromboththephasenoiseandthepowerfluctuation.Furthermore,fordegradedinjectionsignalswithanopticalsignal-to-noiseratioaslowas4.1dBanda25kmlongdistancetransmission,good-qualityopticalclocksareallsuccessfullyrecovered.

简介：Anovelmethodfordistortion-freeopticalpulsetransmissionistheoreticallyproposedandsimulated,inwhichtwotimelensesformedbydispersionfibersandquadraticphasemodulationsareutilized.OneisusedasanopticalinverseFouriertransformation(OIFT)devicetotransformtheinitialtime-domaindatatofrequency-domainoneatthetransmitterandtheotherasanopticalFouriertransformation(OFT)devicetorecoverthedataatthereceiver.Byusingtheunchangedspectralenvelopeinlinearopticalfibercommunication,theinitialdatacanberecovered.Throughsimulations,a10×100Gb/sintensitymodulateddirect-detection(IM-DD)densewavelengthdivisionmultiplexing(DWDM)systemover2000kmtransmissionwithoutthecompensationforpolarizationmodedispersion(PMD)anddispersionslopeisachieved,whichcanbeusedtoupgradethecurrent10-Gb/sIM-DDsystemtoa100-Gb/sonedirectly.

简介：A100-Gb/shigh-speedopticaltransmitterisproposedandexperimentallydemonstrated.Basedonfrequency-quadruplingtechnique,twosub-channelswithafixed50-GHzspacingareobtainedfromonelasersource.Usingreturn-to-zerodifferentialquadraturephase-shiftkeying(RZ-DQPSK)modulationformatandpolarizationmultiplexing(PolMux),onlylow-speedelectronicdevicesof12.5GHzareneededforthe100-Gb/stransmitter.Thiseliminatestheneedofultrahigh-speedoptoelectronicdevicesandthusgreatlyreducesthecost.Theexperimentalresultsshowthatthistransmittercanachievegoodperfor-manceindispersiontoleranceofa25-kmsinglemodefiber(SMF).

简介：为满足性能良好、运行稳定、精度高的触摸屏在嵌入式系统中的广泛应用，提出了一种嵌入式系统的触摸屏驱动设计，这种方案基于S3C2410微处理器与触摸屏的硬件接口在嵌入式UCOS操作系统中的软件驱动实现，采用外部晶体管连接触摸屏到S3C2410的接口电路，并利用S3C2410的等待中断模式和自动X-Y坐标转换工作模式，读出与X-Y坐标有关的电压值。高效地完成了触摸状态的检测以及触摸数据的转换，其实现方法具有简便高效，易于实现等特点。

简介：Alowcost8×10-Gb/stransmissionsystemover1500kmonconventionalfiberusingchirpedfiberBragggrating(CFBG)asdispersioncompensatorisdemonstrated.Thebiterrorrate(BER)below10-10at1500kmisobtained.Thechannelspacingis0.8nmandtheopticalamplifierspacingis100km.Only16erbium-dopedfiberamplifiers(EDFAs)areused.

简介：Non-uniformstep-sizedistributionisimplementedforsplit-stepbasednonlinearcompensationinsingle-channel112-Gb/s16quadratureamplitudemodulation(QAM)transmission.Numericalsimulationsofthesystemincludinga20×80kmuncompensatedlinkareperformedusinglogarithmicstepsizedistributiontocompensatesignaldistortions.50%ofreductioninnumberofstepswithrespecttousingconstantstepsizesisobserved.Theperformanceisfurtherimprovedbyoptimizingnonlinearcalculatingposition(NLCP)incaseofusingconstantstepsizeswhileNLCPoptimizationbecomesunnecessarywhenusinglogarithmicstepsizes,whichreducesthecomputationaleffortduetouniformlydistributednonlinearphaseforallsuccessivesteps.

简介：受中国光学学会委托，中国光学学会光学测试专业委员会订于2014年10月下旬在江西南昌召开第十五届全国光学测试学术交流会，本届会议由南昌航空大学承办。本届年会适逢“十二五”项目实施的关键阶段，将特邀院士与国内著名专家做大会报告，广泛欢迎全国从事光学及光电测试等相关领域的科技人员参加，交流“十二五”阶段的学术研究、技术开发的新进展，研讨新动态、新领域，同时欢迎公司企事业单位到会展示技术成果，洽谈产、学、研合作。

简介：受中国光学学会委托，中国光学学会光学测试专业委员会将于2012年9月21日在四川绵阳召开第十四届全国光学测试学术交流会，本届会议由中国工程物理研究院第八研究所和第十研究所共同承办。本届年会特邀院士与国内著名专家做大会报告，将广泛欢迎全国从事光学及光电测试等相关领域的科技人员参加，交流学术研究、技术开发的新进展，研讨新动态、新领域，同时欢迎公司企事业单位到会展示技术成果，洽谈产、学、研合作。

简介：Weexperimentallydemonstratea4-Gb/sradio-over-fiber(RoF)systemwith40-kmfiberand2-mwirelessdistancedownstreamat100-GHzcarrier.Tothebestofourknowledge,thisisforthefirsttimeinChinatorealizeopticalwirelesslinkat100GHz.Inthisletter,simpleintensitymodulatorwithdirectdetector(IM-DD)modulationisemployedandopticalpowerpenaltyafter40-kmsinglemodefiber(SMF)-28and2-mairlinkis3.2dBwithbit-error-rate(BER)at1×109.