IPS_FFS面板原理介绍-V2

IPS/FFS面板原理介紹廣視角技術介紹廣視角技術介紹•NarrowViewingAngledueto•1)Anisotropyofliquidcrystal(Δn,Δε)•2)DifferentTransmittancewithviewangle•3)ImperfectlightcontrolbyPolarizedandRefractedLightToSolvetheseproblems,*InPlaneDrivingsuchasFFS,IPS*VA,OCB…withCompensationFilm*Dual~multidomainPolarizerAnalyzer+LCCR=NormalOffOnOffOnOffOnCR=BadCR=GoodLCPolarizedLightΔn(Θ,Φ,λ)ΘΦ技術RelationshipMapIPS:In-planeSwitchingFFS:FringeFieldSwitchingVA:VerticalAlignmentHYDISBOEOTLGDHitachiLGDSamsungSamsungSharpCMIAUOPLD(IPS-α)NECHannstarCMIFFSFFSIPSIPSVAVAHitachi(PVA)(ASV/MVA)(MVA)(MVA)(PLS)Sony(SVA)SonyHannstar(AH-IPS)TMDCMIAUOSharp(SuperLCD)(HS-IPS)TMDIn-PlaneSwitch(IPS)mode簡介•IPS起初是由Hitachi所發展。它與使用TN+Film(TN型+廣視角膜)技術不同的地方是液晶分子的動作方向平行於玻璃基板。IPS的基本原理•利用橫向電場來驅動液晶,以達到廣視角目的理論上IPS可以選用正型或負型液晶：正型(//)液晶分子平行電場排列負型(//)液晶分子垂直電場排列電場方向OffstateOnstate電場方向OffstateOnstate1.正型液晶（0）液晶分子的指向矢平行電場2.負型液晶（0）液晶分子的指向矢垂直電場•IPS透過率(Tr)公式：其中(E)代表液晶分子旋轉角度，與橫向電場大小及液晶分子Rubbing角度有關。從Tr公式中可以發現當(E)=45o時，sin2(2(E))=1是最大值。電極配置與Rubbing方向必須能讓液晶分子容易形成45o的旋轉。電極配置與Rubbing夾角的限制：0o45oE(橫向電場)液晶分子(E)電極電極)nd(sin))E(2(sin21Tr22IPS的基本原理IPSModeEvolution(ConventionalIPS)•傳統的(IPSMODE)最初配向方向Colorshift:()平行液晶分子方向偏黃(II)垂直液晶分子方向偏青偏黃偏青IPSModeEvolution(S-IPS)•新型的(SuperIPSMode)最初配向方向*藉由形成多域結構降低液晶分子的n變化量的方式有效地抑制colorshiftIPSModeEvolution(AS-IPSandIPS-Pro)IPSModeEvolution(AS-IPSandIPS-Pro)ConventionalIPSandNew-IPS對比比較ColorWashoutReverseRotationReverseRotationLC材料的選擇•從應答時間,驅動電壓及透過率來考量:•1.應答時間方面~大,小•2.驅動電壓方面~大,K22小•3.透過率方面~ndCF特性1.使用樹脂BM(不可用金屬BM)2.OC層(IPS技術非常重視平坦度)3.裡面ITO(色製層相反側,可有可無，色製層側不可做ITO)P.S.不須打transferPL特性•要求特性抗靜電•以295WA01為例,偏光板採用:CF:NPF-SEG1224DUCAGS1[日東]TFT:NPF-SEG1224DUCAGS1[日東](表面具導電粒子,抗靜電用表面)PI特性配向布特性FringeFieldSwitch(FFS)mode簡介`InPlaneSwitchingAdvancedFringeFieldSwitchingC/FC/FEdwldwlVcomVpixel●AFFS:HighTransmittancebytransparentelectrodeandlowVop●IPS:LowTransmittancebymetalelectrodeandhighVop韓國Hydis(原Hyundai)提出之新型廣視角LCD結構,利用流蘇狀電場分佈驅動液晶分子,使其具有類似於IPS結構的效果.IPSAFFSl/dl/wFieldElectrodes1≤1≤1Ey,Ez(FringeField)Ey(InPlane)1FoldedITOMetalsModeComparisonofAFFSandOthersS-IPS(InPlaneSwitching)C/FwlLightLightC/FdcellLightLightPVA(VerticalAlignment)wlAFFS(Adv.FringeFieldSwitching)AFFS(Adv.FringeFieldSwitching)C/FLightLightITOelectrodeMetalelectrodeElectricFieldHighTransmittance(TransparentElectrode)Low_DrivingVoltage&_PowerConsumptionHigherContrastRatioCo-planeFringeField(Ey,Ez)Higher_DrivingVoltage&_PowerConsumptionHigherContrastRatioVerticalField(Ez)dfield3.5μm(dcell)lwdSiNx~600nmTransmittance=Tosin22Φsin2(πdΔn/λ)dcellPixelImageComparisonofAFFSandothersS-PVAAFFSAS-IPSItemAFFS(measured)AS-IPS(S-IPS)(Reference)S-PVA(PVA)(Reference)CleanImageVividMovingColorGoodColorHighDynamicCRHighStaticCRFaston/offTransmittance5%3.8%4.9%ContrastRatio~800:1~650:1~900:1LowPowerConsumption•TheLowestDrivingVoltageintheothernormallyblackmodesFFSisavailableforLowerPowerConsumption:10%lowerthanTNmode012345678012345678910Voltage(V)Transmittance(%)FFS(+LC)VA(-LC)IPS(+LC)TN(+LC)OperationVoltageFFS,TN:3~4V→RealizationoflowpowerconsumptionIPS,VA:5~6V(duetoslitgap(IPS),negativeLCcausetoLowdielectricconstants(VA))SmudgeFreeCo-planealignedLCmoleculesleavenorippleswhenthedisplayistouchedandpressurized⇒Pooling(pushing)Trace⇒Disappearweightingof500gWhiteBlack*NormallyWhite(TN)1s2s*NormallyBlack(VA,IPS)3s1s*AFFSMode1s1sPooling(PenPressing)DistortedLCscanbefastrecoveredbyhighfringeelectric(magnetic)fieldandhorizontalalignment~6.2V/μm(IPS~0.8V/μm)DistortedLCscan’tberecoveredBythepropagationofEfieldviaverticalelectrode,lowfieldandverticalalign.~0.8V/μmAFFSDisplayOtherDisplay(TN,VA…)CauseofRipple/PoolingFreeFlickering透過率影響參數電極寬度(l)電極間距(w)CellGapRubbingdirection電極傾斜角度正負型液晶FFS技術分析~TvsLC1.FFS的電場有Ey,Ez方向電場,若使用正型液晶分子,液晶分子隨著電力線排列,透過率也隨著電場分布波動.(keypoint)手法一:使用負型液晶分子則可減緩液晶分子透過率隨電場分布波動.手法二:電力線1.電極寬度vs.電極間距2.cellgap和電極間距的關係.FFS技術分析~CF•Colorfilter:IPSmode:1).使用樹脂BM(CrBM產生disturbin-planefield).2).高阻值的樹脂BM(以消除BM和dataline之間的橫向電場).FFSmode:1).可使用CrBM或樹脂BM.2).高阻值的樹脂BM3).CrBM或樹脂BM對操作電壓的影響BMV10V50V90Resin2.213.304.88Cr2.213.314.90MicrographofNewPixel(AdvancedFFS)SpecialFeatures:1.LCdirectorisparalleltotheelectricfieldgeneratedbetweenpixelanddatalineLCdirectorremainsattheoriginalstateNolightleakageNarrowBMIncreasinglightefficient2.NearfuturetheBMonthedatalinewillbeverymuchnarroweddownfurtherUltra-FFS面板結構SpecialFeatures:1.UFFS:LCmoleculesrotateintwooppositedirectionswithappliedvoltageColorShiftisminimizedduetoaself-compensatedeffect2.FFS:ColorShiftoccursbecausethedDnalongparallelandperpendiculartotheLCdirectorisdifferentUltra-FFS面板結構•運用2-Domain設計,使色散更小ColorCoordinates/ViewingAngleofFFSModelMVA,MVABumpless,HHSComparisonTech.DevelopDepart.MVAMVABumplessHHSInfra-structureOMFigureHHSManufacturingParameterTech.DevelopDepart.TFTComparisonRetardationComparisonHHSOMPerformanceTech.DevelopDepart.3.8um(D)W=4S=64.2um(D)4.6um(D)W=6S=4OHHSOMPerformance(W4S6)Tech.DevelopDepart.HHSOMPerformance(W6S4)Tech.DevelopDepart.Tech.DevelopDepart.MVA,MVABumplessandHHSComparisonHHS:TrendAnalysis(I)1.Transmittanc