发射和接收光束同时开关的激光测距法

:025827025(2006)0320391205,,,,(,201800),,,,,,,,LiNbO3,;;;;P225.2ALaserRangingbySimultaneousSwitchingofTransmittingandReceivingBeamsZHAODong,LIULi2ren,WANGJi2ming,PANWei2qing,LANGHai2tao(ShanghaiInstituteofOpticsandFineMechanics,TheChineseAcademyofSciences,Shanghai201800,China)AbstractBysimultaneousswitchingoftransmittingandreceivingbeamsinanelectro2opticaldevice,anovellaserrangingmethodisproposed.Continuouswave(CW)laseremittedbylasertransmittergoesforwardtothemeasuredobject,beingreflectedbytheobject,thengoesbacktothetransmitter.Closetothetransmitter,anelectro2opticalcrystalisaddedintotheround2triplightrays.Highvoltagecurvewiththesteepenoughedgesisaddedonthecrystal.Becauseofthehighspeedswitcheffect,thecrystaloperatesonthetransmittingandreceivingbeamsatthesametime.Solightpulses,whosewidthTcontainstherequiredrangeinformation,arecutoffanddetected.Inexperimentsthechangingtimeofhighvoltageisaboutseveralnanosecondsrealizedbyavalanchetriodecircuit.Andbasedondoublerefractionandtotalinternaldoublereflectioneffectincrystal,asingleblockLiNbO3crystalwithspecialshapeisdesignedasthemaindeviceofthismethod.Thefeasibilityofthenewideaisprovedbytheresultsfromoscillograph.Soabrand2newwayforthelaserrangingisprovided.Keywordsmeasurement;laserranging;electro2opticeffect;doublerefraction;totalinternaldoublereflection:2005205217;:2005208231:(1979),,,,E2mail:[e-mail]1,,,[1,2],;,,:,,,[38],33320063CHINESEJOURNALOFLASERSVol.33,No.3March,200621,,45,,;,,,,,,TRT,R=cT/2,(1)c1Fig.1Gettinglightpulsebyinstantaneouslyinsertingareflectmirror245LiNbO3Fig.2Laserrangingusinga45cutrectangularparallelepipedLiNbO3crystal,2,45LiNbO3,y,z45,x,Cz45,,oe45,45(28)[913],,o;ez2,,z5,yzo,o,o,,x,x,yx,y45,1n2o-22Ex2+1n2o+22Ey2+1n2ez2=1,(2)22V,,,xoye,45,-y2,-y5,[913],();,,xo,ye,e,xo,o,,(),V,,R33(a),trV,,,,3(b)T,,293332,E2=12Im{1-cos[Mf(t)]},(3)Im,f(t),MM=2lVmd(n3022),(4)l,d,,Vm,n03(c)Mf(t),(),,,,3(d),1/8(2),/2,,Vm=V/2,,(3)E2=12Im1-cos2+Mf(t),(5)3(a);(b);(c)();(d);(e)/2;(f);(g)Fig.3Theoryanalysisonlightintensitycurvedetectedindifferentconditions(a)waveformofloadedvoltage;(b)detectedidealwaveformoflightpulse;(c)curveoflightintensityversusphasedifference;(d)influenceoninflectionpointsfromnonlinearity;(e)lightpulseafteraddingaphasedifference/2;(f)imperfectpulsewaveformatotherpeakvoltages;(g)influenceoninflectionpointsfromtransit2time3(c)1/8,,V/2,3(e),,,VmV/2(1/8)V(1/8),,3(f),,,,3(g),(l),,,,I,I,T=I(dt/dI)=I[dt/d(E2)],(6)dt/dI,,(5)(6),f(t)=0T=I[dt/(ImMdf/2)],(7)df/dt,,,:1),;2),,(4),,l/d,l,,;3),,,,,44,,He2Ne633nm,1mm,LiNbO3,,3933:,3mm5mm50mm,15mm,51,817V,44GD4251Y,TDS3052B(500MHz,510-4T/s),,,18m4Fig.4Realdevicesinexperiment5Fig.5Voltagepulsecurvefromavalanchetriodecircuit,,55551(110),TDS784D(1GHz,410-4T/s),5ns,20s,20s18m120ns,120ns,10MHz,,817V,6,,,,6Fig.6Lightintensitycurvefromdetectorsystem,,tr,tf,:trc/2,,:tfc/2,:1/(tr+tf),,0175mR2400m,50kHz5,,,;,45LiNbO3,,1A.Yariv,P.Yeh.OpticalWavesinCrystals[M].NewYork:Wiley,19842JiangMinhua.CrystalPhysics[M].Jinan:ShandongScience&TechnologyPress,1980.[M].:,19803AriKilpela.PulsedTime2of2FlightLaserRangeFinderTechniquesforFast,HighPrecisionMeasurementApplications[M].Finland:OuluUniversityPress,20044RaimoAhola,RistoMyllyla.Anewmethodformeasuringthetime2of2flightinfastlaserrangefinding[C].SPIE,1986,654:19215I.Fujima,K.Seta,H.Matsumotoetal..GHztraveling2waveopticalmodulatorforprecisiondistancemeasurement[C].SPIE,1988,889:86906K.Seta,T.Oishi.Distancemeasurementusingapulsetrainemittedfromalaserdiode[J].J.Appl.Phys.,1987,26(10):169016927K.Nakamura,T.Hara,M.Yoshidaetal..Opticalfrequencydomainrangingbyafrequency2shiftedfeedbacklaser[J].IEEEJ.QuantumElectron.,2000,36(3):3053168E.A.Wachter,W.G.Fisher.Coherent2burstlaserranging:decouplingresolutionandunambiguousrange[J].Opt.Lett.,1997,22(8):570572493339RenHaixia,LiuLiren,SongZheetal..Doublerefractionandreflectionsequentialinterfacesinacrystalandapplicationtointegrationof1Nopticalswitch[J].ActaOpticaSinica,2004,24(2):152157,,.:1N[J]1,2004,24(2):15215710SongZhe,LiuLiren,RenHaixiaetal..Integratedopticalbypass2exchangeswitch[J].ActaOpticaSinica,2004,24(6):777780,,.22[J]1,2004,24(6):77778011HaixiaRen,LirenLiu,DeanLiuetal..Doublerefractionandreflectionofsequentialinterfacesinacrystalandapplicationtointegrationof1Nopticalswitch[J].JournalofModernOptics,2003,50(14):2231224212HaixiaRen,LirenLiu,ZheSongetal..SingleLiNbO3slabintegrated1Nelectro2opticswitch[C].SPIE,2003,5201:18018913HaixiaRen,LirenLiu,DeanLiuetal..Doublerefractionandreflectionofsequentialcrystalinterfaceswitharbitraryorientationoftheopticaxisandapplicationtooptimumdesign[J].JournalofModernOptics,2005,52(4):5295395933: