LCD行业-富相科技-LCD液晶显示器驱动系統（PPT 98页）

液晶顯示器驅動系統講師:課程大綱•液晶物質簡介•液晶的電光效應•液晶基本驅動原理•STNLCDs驅動原理•TFTLCDs驅動原理•影響TFTLCDs畫面品質的因素•DriverIC簡介•TFTLCDs模組及介面技術簡介液晶物質的相變化固體結晶液晶液體加熱加熱冷卻冷卻液晶分子的種類SmecticLC層狀液晶NematicLC線狀液晶CholestericLC膽固醇狀液晶液晶分子的排列CrystallineLiquidCrystallineLiquidKSmCSmANLBiaxialUnaxialIsotropicTemperature液晶的分類層狀液晶Smectic線狀液晶Nematic膽固醇狀液晶Cholesteric液晶分子排列狀態熱致性液晶Thermotropic溶致性液晶Lyotropic液晶形成方式液晶的電光特性•異向性(Anisotropic)–排列因數()–折射率()–黏滯係數()–介電係數()–電導係數–磁化率–彈性係數()oennn//332211,,nS液晶的光學特性OpticalPositiveOpticalNegativeHelicalAxisOpticalAxisOpticalAxisnno//nnenne222//nnnoonenonen液晶驅動原理電極電極液晶FieldOFFFieldON0//液晶顯示器主要優缺點•優點–低電壓驅動。–低消耗電流。–體積薄，重量輕。–可實現大面積化。–彩色化容易。•缺點–視角限制。–外加被光源或投射光源。–溫度操作範圍限制。液晶顯示器的種類液晶顯示器扭轉型(TwinstNematic,TN)1971超扭轉型(SuperTwinstNematic,STN)1984雙層雙扭轉型(DoubleLayerSTN,DSTN)1987光相位補償超扭轉型(FilmSTN,FSTN)1988主動驅動超扭轉型(AASTNorMLSSTN)1992強介電型(FerroelectricLiquidCrystal:FLC)1980PDLC(PolymerDispersiveLC)1988PSCT(PolymerStabilizedCholestericTexture)1993OtherDS(DynamicScattering)1968PC(PhaseChange)1968GH(GuestHost)1968ECB(ElcetricalControlBirefregency)1971BTN(BistableTwistNematic)1995IPS(InPlaneSwitch)1995VA(VerticalAlignment)1996TN型LCDs顯示原理Twist90液晶分子FieldOFFFieldON利用液晶的旋光特性調變穿透光線液晶的旋光特性消失STNLCDs顯示原理Twist270液晶分子FieldOFFFieldON利用液晶的雙折射特性調變穿透光線TN&STN電光轉移曲線V-TCurve100%90%10%VnsSTNVsSTNVsTNVnsTNTVTN與STN的電壓漂移T100%VV2T1TTNModeT100%VV2T1TSTNModeLCDs驅動方式•直接驅動法(DirectionAddressing)•靜態驅動法(StaticAddressing)•多工驅動法(MultiplexAddressing)•主動驅動法(ActiveAddressing/Multi-LineSelection)•主動矩陣驅動法(ActiveMatrixAddressing)•兩端元件(MIM,Diode..)•三端元件(A-Si:HTFT,Ploy-SiTFT..)•PlasmaAddressing(PALC)•熱掃描驅動法(雷射掃描)•光掃描驅動法(電子速掃描LCDs靜態驅動法LCCellXORVsVcVsigVcVsigVcVsVc-VsONOFF多工驅動法(振幅選擇驅動法,APT)1234N123Frame1Frame2F0T水平掃描訊號+D-D0垂直影像訊號Row1Row2Row3RowNColumn1ONOFFONOFFF+DF-DF+DF-D+D-D0+D-D0+D-D0+D-D01234NFrame1液晶畫素電壓TNDNDFON221NDNDFOFF221OFFONSRNDFopt11NNSRopt多工驅動法的限制NBiasS.R.21:22.2331:21.7331:31.9241:31.7381:41.45161:51.29321:71.2641:91.151001:111.111281:121.092001:151.082401:161.064001:171.061.01.11.21.3100200APT驅動波形432105432106543210N=10N=20N=30ON=1.387ON=1.255ON=1.172OFF=1.000OFF=1.000OFF=1.000IAPT驅動波形水平電壓波形垂直電壓波形液晶畫素電壓波形0+F0+D-DF+D-D+D-(F+D)F+D-D+D-(F+D)F+D+D+F0+2D0F-DF+D正極性驅動負極性驅動正極性驅動波形偏移+D負極性驅動電壓偏移+FAPTAddressingIAPTAddressingAPT與IAPT方式比較•APTAddressing–LowVoltageSegmentDriver:2D–HighVoltageCommonDriver:2F•IAPTAddressing–Offset+DforPositivePolarity–Offset+FforNegativePolarity–VoltageRangeofSegmentDriver:F+D–VoltageRangeofCommonDriver:F+D高容量多工驅動的對策(a)(b)(c)(d)(e)STNLCDs規格11%1001%10011111090NNSRSRVVNVDBDNDFVoptlcdlcdOperationVoltageVop:BiasRatio:Steepness:NDNDFON221NDNDFOFF221OFFONSRNDFoptSelectionRatio:STNLCDs驅動電壓計算IfVoff=2V,N=240rows,Then:07.114.268.23120.2248.135.1240239115112222SRVONVVDNVVFVDDDNDNDNOFFVonLCDoffAPT:SegmentDriver:2.96V,CommonDriver:44.40VIAPT:Segment&CommonDrivers:23.68VSTNLCDsDrivers架構電源電壓Vlcd接地RRRR(F/D-3)RF+DFF-D2DD0......移位暫存器(ShifterRegister)DCLK串列輸入訊號...閂鎖暫存器(LatchRegister)LPF+D0F-D2D偏壓位準........................................................DF(HLHL...H)............................HLHH並列輸出垂直訊號電極2D02D2DIAPT參考電壓IAPT驅動IC灰階顯示─FRC•FrameRateControl,FRC:1stFrame2ndFrame3rdFrame4thFramePixel1Pixel2Pixel3Pixel4Pixel55/5ON4/5gray3/5gray2/5gray1/5OFFResultTime灰階顯示─PWM•PulseWidthModulation,PWM:垂直影像訊號電壓波形水平掃描電壓波形液晶畫素電壓波形ΔTf1-fD-DFF+DF-D+D-D00灰階顯示─PHM•PulseHighModulation,PHM:垂直影像訊號電壓波形水平掃描電壓波形ΔTf1-f+D-DFF+DF-D+D-D00+D-DXYPWMPHM液晶畫素波形液晶畫素波形ΔT/2ΔT/2液晶的頻率響應101001k10k100k1.031.021.011.000.990.980.970.96正規化處理V50頻率VerticalCrosstalkofSTNLCDsAB1HF-D+D-DF-D+D-D+D-DFrameNFrameN+10F+D-D+D-D正極性驅動波形負極性驅動波形水平脈波垂直驅動波形液晶畫素電壓波形ABABVerticalCrosstalk的抑制(一)1HF-D-DF-D+D-D+DFrameN0F+D+D-D正極性驅動波形水平脈波垂直驅動波形液晶畫素電壓波形ABABF-D+D+D-DF-D+D-D+D-DFrameN0F-D+D-D正極性負極性APTAddressingImprovementAddressing每兩條水平線變換一次驅動電壓極性VerticalCrosstalk的抑制(二)1HF-D-DF-D+D-D+DFrameN0F+D+D-D正極性驅動波形水平脈波垂直驅動波形液晶畫素電壓波形ABABF-D+D-DF-D-D+D-DFrameN0F-D+DAPTAddressingImprovementAddressing000FF0正極性驅動波形採用補償驅動週期VerticalCrosstalk的抑制(三)1HF-D-D-DFrameN0F+D+D-D水平脈波垂直驅動波形液晶畫素電壓波形FrameNF+DAPTAddressingIAPTAddressingOFFON-(F-D)+DF+D-(F+D)0F+D+2DF-DF+D0+2DF-DF+D0F-D-D-D+D-(F-D)+DF+D-(F+D)OFFON-F一條水平掃描線的掃描週期分割成兩部份，一半的掃描時間是採用正極性的驅動訊號，另一半的時間是採用負極性的驅動訊號。HorizontalCrosstalkofSTNLCDs垂直驅動訊號LLine水平掃描波形液晶畫素波形(a)(b)(c)(d)ABABLHorizontalCrosstalk的抑制垂直驅動訊號LLine水平掃描波形液晶畫素波形(a)(b)(c)(d)傳統驅動方式水平掃描補償波形補償之液晶畫素波形(e)(f)£GVLABFrameResponseofSTNLCDs慢速液晶快速液晶+20V-20V16.6ms液晶畫素電壓光線穿透率WBActiveAddressingforSTNLCDs圖框週期Δtk=HF1(t)F2(t)F3(t)F4(t)F5(t)ON+1ON+1ON+1OFF-1OFF-1LCDs矩陣ΔtkG1(t)G1(t)=(+F1(t)-F2(t)+F3(t)-F4(t)+F5(t))/√5ActiveAddressing驅動電壓NiiijjtFIctG1tGtFtUjiijNmmmjjiitAINNtGtANNtFNNFOFF12112121Nc1IfVoff=2V,N=240rows,Then:F=0.730X2V=1.460V|G|=0.954X2V=21.909V•OutputRangeofSegmentDriverisabout44V.•CommonDriverofCommonDriverisabout3V.SegmentVoltageofActiveAddressing不同的元素相異數目D所對應的垂直驅動電壓位階N01234567892-10+1－－－－－－－3-1-1/3+1/3+1－－－－－－4-1-1/20+1/2+1－－－－－5-1-3/5-1/5+1/5+3/5+1－－－－6-1-4/6-2/60+2