激光器驱动电路中英文翻译

1、激光器驱动电路中英文翻译激光器驱动电路中英文翻译激光器驱动电路中英文翻译中文2540字LaserdrivercircuitSmallchangeswilldirectlysemiconductorlaserdrivecurrenttotheoutputintensityfluctuation.Tostabilizetheoutputpowersemiconductorlaser,Voltagenegativefeedbackprincipletodesignaconstantcurrentdrivingcircuitcomprisesasoftstartingandcurrentlimitin

2、gprotectioncircuitbasedon;Atthesametime,accordingtotheneedofthelightsourceismodulatedtoeliminatetheinfluenceofbackgroundlightand,integratedlasermodulationcircuitcomprisesacrystaloscillationcircuitanddividercircuitdesign.Makingthespecificcircuitandcompletetherelevantexperimental.Theexperimentalresult

3、sshowthatthecircuitcanprovideadrivingcurrentofhighstability,Currentstabilityupto0.05%;Softstartandcurrent-limitingprotectioncircuitcanprotectthesemiconductorlaserandenhancetheimpactcapability.Modulationcircuitgeneratesacarriersignalneededforlaserdiodemodulationanddirecttocompletetheoutputlightmodula

4、tion,Theswitchcanbeconvenientlyrealizedfrom256Hzto512kHzrangeof12kindsofcommonlyusedmodulationfrequencyselection.Semiconductorlaserwithitsexcellentcharacteristics,highefficiency,simplestructure,smalliswidelyusedinscientificresearch,nationaldefense,medical,andotherareasofprocessing,itsdrivetechnology

5、becomesmoreandmoreimportant.Semiconductorlaseristheidealelectron-photondirectconversiondevices,quantumefficiencyisveryhigh,thecurrentsmallchangeswillleadtoagreatchange,theoutputlightintensityofthetherefore,semiconductorlaserdrivecurrentrequirementsisveryhigh.Drivingtechnologyofsemiconductorlaserusua

6、llyadoptsconstantcurrentdrivemode,thiswork,throughtheprincipleofnegativefeedbackcontrolloop,directlyprovidetheeffectivecontrolofthedrivecurrent.Inaddition,thetransientcurrentorvoltagespikes,andovercurrent,overvoltagewilldamagethesemiconductorlaserdrivecircuit,thereforeshouldbeconsideredintheprotecti

7、oncircuitagainstelectricshockmeasuresandspecial.Insomeapplications,DCsemiconductorlasersproduceDCdrivelightinthemeasurementprocessisvulnerabletointerferencefromambientlightslowchange,whichcouldnotbeseparatedfromtheenvironmentlightrequiredDCopticalsignal,thesignal-to-noiseratioistoosmall,sotocarryont

8、hemodulation.Whenthehigh-speedmodulatedsemiconductorlasers,therewillbedynamiccharacteristicsis1complex,suchastherelaxationoscillation,sincethepulseandmulti-pulsephenomena.Inthispaper,experimentswereconductedtostudythecharacteristicsoflowfrequencymodulation.Semiconductorlaseroutputisstable,andcanbedi

9、rectlymodulated,ithasbeenwidelyappliedinopticalsystem,isthepreferredsourcesensorsystem.Thispaperdescribesthedesignofahighstabilitydrivingcurrent,modulation,simpleoperationandlowcostdrivingcircuitforthelightsourceofopticalfibersystems.Inthispaper,thedesignofdrivingthesemiconductorlasermodulationcircu

10、itcomposedoffourparts,includingconstantcurrentcircuit,asoftstart,currentlimitprotectionandmodulationsignalgeneratingcircuit.Theconstantcurrentcircuittogenerateahighstabledrivecurrent.Softstartistheroleofeliminatingsurgemaybepresentinthecircuit,topreventtheharmofsurgeforlaser.Toavoiddamageduetoovercu

11、rrentcausedbysemiconductorlasercannotberestored,thenaddingcurrent-limitingprotectioninadrivercircuit.Circuittorealizethemodulationandfrequencycanbeadjustedtogenerateamodulatedsignal.Theconstantcurrentcircuitisshowninfigure1,Thein-phaseendvoltagereferenceVrintoA1opamp,theoperationalcontrolamplifierco

12、nductinglevel,andthustoobtainthecorrespondingoutputcurrent.TheoutputcurrentgeneratedbysamplingvoltagesamplingresistorRs,thesamplingvoltageisamplifiedastheinvertinginputvoltagefeedbackvoltagefeedbackamplifierA1,andvoltageandthein-phaseinputendofcomparison,Q2toadjusttheoutputvoltagethroughthetriode,ad

13、justmentandoutputcurrentofsemiconductorlasers,sothatthewholeclosed-loopfeedbacksysteminthedynamicbalance.+12VR7A11KQ2Vr2N2222AOPAMPU71-12V2laserAR?61OPAMPR81A1R5A161R6A161M5.1KFigure1ConstantcurrentmapBecausetheswitchinstantaneousinpowersupplygeneratesavoltage,currentsurge,aswellasthesurgeinterferen

14、ceeffectsarelikelytocausethebreakdownand2thedamageofthesemiconductorlaser,andthereforemustbeinthedesignofsoftstartcircuitdrivelaser,namelytheuseofthechargeanddischargeofRCcircuit,delaytime,thespecificcircuitasshowninFigure2asshownin.SwitchS1isclosed,thecurrentthroughtheresistorR1andcapacitorC3tochar

15、ge,thebaseelectrodeofthetriodeQvoltagegraduallyrises.Asthecapacitorchargingandtheconductionofthetriode,outputvoltageVoisachievedfrom0tothemaximumriseslowly,untilthecapacitorchargesaturation,thevoltageandcurrentstabilizing.Whenthepowersupplyisdisconnected,theprocessofreverse,soastorealizethecurrentan

16、dvoltagedecreasesslowly.S1U1R1Q78L052N2222A1Vout31MVinDNGC3C6C21051052104V0Figure2SoftstartcircuitdiagramLasersoftstarttimeandthechargingcapacitorandthecorrespondingresistance,whenthecapacitorchargingtendstosaturation,theoutputvoltagesoftstartcircuitcanachievemaximum.PowersupplyvoltageisVI,thecapaci

17、torvoltageisVo,thecapacitorchargingformula:1V0Vi(1eRC)Accordingtothisformulacancalculatetheelectricchargeanddischargetime.Semiconductorlaserwithotherdevices,havenormalworkingcurrent,ifthecurrentexceedsthisrange,thelaserwillbedamaged,thereforemustrestrictcurrentlaserinthesetrange.Emittervoltagetransi

18、storQ2asthefeedbackvoltageterminalphaseinA3opamp,whenthefeedbackvoltageislessthanthelimitvoltage,VA3opampoutputlowlevel,thetransistorQ1isturnedon,thistimebyatriodeQ2outputvoltagefeedbackvoltageisgreaterthanthelimit;whenthevoltageofV,A3opampoutputhigh,triodeQ1cutoff,thislimitsthetriodeQ2emissionincre

19、asesverycurrent,andislimitedtoaspecificvalue.SoevenifthecurrentcausedbyVrcontrolvoltageexceedstheset3value,thetriodeQ1andQ2areconnectedinseries,sothetotalcurrentwillbeclampedinthesettingcurrentvalue.Modulationsignalgeneratingcircuitiscomposedofacrystaloscillatingcircuitanddividercircuitiscomposedoft

20、woparts,usedtogeneratethehighstabilityoffrequency,dutycyclesquarewavesignalisstable.Crystaloscillatingcircuitdirectlygeneratedbytheactiveoscillator,oscillationfrequencyis1MHz.FrequencydividercircuitcomposedofaCMOSintegratedcircuit4040.1MHzpulsesignalafterthefrequencyby4040,pinoutputfrequencyfromthes

21、witchisselected,thedutycycleis50%,amplitudeis5Vsquarewavesignal.Themodulationfrequencydividingfrequencywere256Hz,512Hz,1kHz,2kHz,4kHz,8kHz,16kHz,32kHz,64kHz128kHz,256kHz,512kHz.Drivinganimportanttechnicalparametersofcircuitforcurrentstability.Currentstabilityisinacertainperiodoftime,severalmeasureme

22、ntsthroughthecurrentsizeofthesemiconductorlaser,namelytheratioofoutputcurrentstabilityfortherelativechangeamountandinputcurrent,stabilitycalculation,therewillbecurrentrelativechangeisdefinedasthemeasurementofthemaximumandminimumvalues,willmeasuretheaveragevalueastheinputcurrentvalue.Drivecircuitbase

23、donvoltagenegativefeedbackprinciple,byconstantcurrentdrivemodetorealizethecontroloftheinjectioncurrentandoutputpowerofsemiconductorlaser,anditcanprovidehighstableoutputcurrent,currentstability0.05%.Drivecircuitwithsoftstart,currentlimitcircuitprotection,reducethedamageofsemiconductorlasertosurgebrea

24、kdownandcurrent,themodulationcircuitandthedrivecircuiteffectivelycombined,realizethefrequencyis,thedevelopmentofnewtechnologyofopticalfibercommunicationisessential.Thecausesofdispersion:Oneisthelightemittedbythelightsourceisnotmonochromaticlight;twoisthemodulationsignalhasacertainbandwidth.Thedisper

25、sionoftheclassification:Bydifferentmodesordifferentfrequency(orwavelength)lightsignalcomponents,transmissioninopticalfibers,duetothephysicalphenomenonofdifferentgroupvelocitiescausesignaldistortioniscalledfiberdispersion.Thefiberdispersionisdividedintomodedispersion(orintermodaldistortion),materiald

26、ispersionandwaveguidedispersion.Aftertwokindsofdispersionisthedispersionapattern,alsoknownasintra-modaldispersion.Dispersionharm:Fiberdispersioninopticalsignalwaveformdistortion,performanceforthepulsewidth,itisthetimedomaincharacteristicsofopticalfiber.4Indigitalcommunicationsystem,pulsebroadeningof

27、opticalsignalisanimportantindex.Pulsebroadeningistoolargecancauseadjacentpulsegapdecreases,theadjacentpulsewilloverlapandregenerativerepeaterdecisionerrorsoccur,whichincreasestheBER,transmissionbandwidthnarrowing,limitthetransmissioncapacityofopticalfiber.Saidmethodofdispersion:Commonlyuseddispersio

28、nrepresentationhasmaximumtimedelayfor$S,pulsewidthRandopticalbandwidthof3dBBthree.Themaximumtimedelaydifferencedelaydescriptionfiberinthefastestandmostslowwavecomponent.Usedtodescribetheeffectoffiberdispersiononthetransmissionsignalpulsebroadeningandopticalfiberbandwidth.Asectionofopticalfiberasanet

29、workanalysisofthedispersioncharacteristics,theavailabletimedomainmethodandfrequencydomainmethod.Wheninthetimedomainanalysis,dispersioneffectisrepresentedbythepulsebroadening,andanalyzedinthefrequencydomain,thetransmissionbandwidthsaid.5激光器驱动电路半导体激光器驱动电流的微小变化将直接致使其输出光强的颠簸。为实现半导体激光器的坚固功率输出,鉴于电压负反应原理设计

30、了包含软启动和限流保护电路的恒流驱动电路;同时针对为除去背景光的影响而对光源进行调制的需要,设计了包含晶体振荡电路和分频电路的集成激光器调制电路。制作详细电路并完成了有关实验。实验结果表示该电路能够供给高坚固度的驱动电流,电流坚固度达0.05%;软启动和限流保护电路可保护半导体激光器并提升其抗冲击能力。调制电路产生半导体激光器调制所需的载波信号并直接达成输出光调制,经过开关可方便地实现从256Hz到512kHz范围内12种常用调制频次的选择。半导体激光器以其超小型、高效率、构造简单等优秀特色被广泛应用于科研、国防、医疗、加工等领域,其相应的驱动技术也显得愈来愈重要。半导体激光器是理想的电子-光

31、子直接变换器件,有很高的量子效率,微小的电流变化都将致使其输出光强的很大变化,所以,半导体激光器的驱动电流要求特别高。半导体激光器的驱动技术平常采纳恒流驱动方式,在此工作方式下,经过负反应原理控制回路,直接供给驱动电流的有效控制。其余,瞬态的电流或电压尖峰脉冲,以及过流、过压都会破坏半导体激光器,所以驱动电路中还应试虑特其余抗电冲击举措和保护电路。在一些丈量应用中,直流驱动的半导体激光器产生的直流光在丈量过程中简单遇到迟缓变化的环境光的搅乱,致使没法从环境光中分别出所需直流光信号,本文系统信噪比过小,所以要对其进行调制。当半导体激光器进行高速调制时,会出现很复杂的动向特色,如驰豫振荡、自脉动以

32、及多脉冲等现象。本文对其低频调制特色进行了实验研究。半导体激光器输出有足够的坚固性,且可直接调制,它已在光纤系统中获取广泛应用,是传感器系统的首选光源。本文为光纤系统的光源设计了一种高坚固度驱动电流、可调制、操作简单且成本低价的驱动电路。本文设计的半导体激光器驱动调制电路由四大多数构成,包含恒流电路、软启动、限流保护和调制信号产生电路。恒流电路产生高坚固度驱动电流。软启动的作用是除去电路中可能存在的浪涌,防备浪涌对激光器的危害。为防备因为过流等要素惹起半导体激光器不能够恢复的破坏,则在驱动电路中加入限流保护。调制信号产生电路实现调制和频次可调。实质的恒流电路见图1,基准电压Vr送入运放A1的同

33、相端,该运放控制放大器的导通程度,并由此获取相应的输出电流。该输出电流经过取样电阻Rs产生取样6电压,该取样电压经放大后作为反应电压反应回电压放大器A1的反相输入端,并与同相输入端的电压比较,经过三极管Q2对输出电压进行调整,从而对半导体激光器的输出电流进行调整,使整个闭环反应系统处于动向的均衡中。+12VR7A11KQ2Vr2N2222AOPAMPU71-12V2laserAR?61OPAMPR81AR5AR6A1161161M5.1K图1恒定电流图因为在电源开关开启的瞬时会产生电压、电漂泊涌冲击,以及外界搅乱产生的浪涌影响都有可能造成半导体激光器的击穿和破坏,所以必然在激光器驱动电路中设计

34、软启动电路,即利用RC电路的充放电,实现时间上的延缓,详细电路如图2所示。开关S1闭合后,电流经电阻R1向电容C3充电,三极管Q基极电压渐渐高升。跟着电容的充电以及三极管的导通,输出电压Vo实现了从0到最大的迟缓上涨,直到电容充电饱和后,此时电压和电流趋于坚固。当电源断开时,上述过程反向,从而实现电流和电压的迟缓降落。S1U1R1Q78L052N2222A1Vout31MVinDNGC3C62C2105105104V0图2软启动电路图激光器的软启动时间与充电电容和相应电阻有关,当电容充电趋于饱和时,软启动电路的输出电压能够达到最大。设电源电压为Vi,电容电压为Vo,电容充电公式为:71V0Vi(1eRC)依据此公式能够计算电路充放电的时间。半导体激光器同其余器件同样,都有正常工作电流,假如电流超出这个范围,激光器将会被破坏,所以必然把激光器的工作电流限制在设定范围内。三极管Q2的发射极电压作为反应电压加在运放A3的同相端,