(1129) TFTLCD液晶显示器显示原理

CMO/IDTechConfidentialTFTLCD液晶顯示器顯示原理Shih-haoOu/歐士豪開發三部開發二課#56869CMO/IDTechConfidential‧TFT-LCDPanel的構造‧TFT-LCD顯示器產品特性與規格‧TFT-LCD驅動原理簡介OutlineCMO/IDTechConfidentialTFT-LCDPanel的構造CMO/IDTechConfidentialTFT-LCD結構示意圖ScanLine掃描線DataLine訊號線電腦圖像顯示TFT-LCDPanel的構造CMO/IDTechConfidentialPCB燈管TFTPolarizer偏光板CFPolarizer偏光板ScanLine掃描線DataLine訊號線液晶TFT-LCDPanel的構造CMO/IDTechConfidentialLightCCFLLampreflectorProtector(diffuser)PrismIPrismIIDiffuserLightGuidePlateReflectionPlateTFT-LCDPanel的構造‧BacklightOpticalConfiguration：CMO/IDTechConfidential‧TNModule穿透率：PCBCCFL(coldcathodefluorescenttube)TFTPolarizer偏光板CFPolarizer元件穿透率Polarizer39.00%TFT-LCD開口率61.00%CF33.00%Total7.85%TFT-LCDPanel的構造CMO/IDTechConfidentialTFT-LCD顯示器產品特性與規格CMO/IDTechConfidential解析度(Resolution)水平(Horizontal)垂直(Vertical)比例VGA6404804:3SVGA8006004:3XGA10247684:3WXGA128080016:9SXGA128010245:4SXGA+140010504:3UXGA160012004:3在同一尺寸下，解析度越高，畫質就越細膩尺寸顏色深度解析度對比亮度反應時間廣視角省電重量NB10.4~17vvvMonitor15~20vvvvvTV20vvvvvTFT-LCD顯示器產品特性與規格‧產品特性：CMO/IDTechConfidentialRedGreenBlueWhiteGrayScale0816243240485663Forcolordepth6bits,Thereare26x26x26=262,144colorsForcolordepth8bitsThereare28x28x28=16,777,216colorsTFT-LCD顯示器產品特性與規格‧顏色深度：CMO/IDTechConfidential0.00.10.20.33804805806807800.00.20.40.60.81.03804805806807800.00.10.10.20.20.30.33804805806807800.00.10.10.20.20.33804805806807800.00.10.10.20.20.30.3380480580680780BacklightColorFilterBfilteredGfilteredRfiltered610nm545nm435nm490nmTFT-LCD顯示器產品特性與規格‧Color：CMO/IDTechConfidentialContrastRatio(CR/對比):CR=L255/L0L255:Luminanceofgraylevel255(最大亮度/nits)L0:Luminanceofgraylevel0(最小亮度/nits)Photometer(TOPCONBM-5A)FieldofView=2º500mmLCDModuleLCDPanelCenteroftheScreenLightShieldRoomTFT-LCD顯示器產品特性與規格‧對比與亮度：CMO/IDTechConfidentialTr0TrTf0TfsignalLuminancetimetime100%90%10%0%risefallForNormallyWhiteResponseTime(TR,TF):TR+TFTFT-LCD顯示器產品特性與規格‧反應時間：CMO/IDTechConfidentialPolarizer穿透軸2046810TFT-LCD顯示器產品特性與規格‧Viewingangleprobleminsingle-domainVA：CMO/IDTechConfidential•WideViewFilm：由FujiFilm獨家開發•分子排列結構與TN-LCD暗態時相同•「負的雙折射效應」(nx=nynz)可與液晶的「正的雙折射效應」(nx=nynz)互相抵消資料來源：FujiFilm’sWebsiteTFT-LCD顯示器產品特性與規格‧廣視角技術─TN+film：CMO/IDTechConfidential。VA：不加電壓時垂直排列。Multi-Domain的目的：產生視覺上平均的效果資料來源：FUJITSUSci.Tech.J.,35,2(Dec.1999)TFT-LCD顯示器產品特性與規格‧廣視角技術─MVA：CMO/IDTechConfidential利用突起物暗示液晶倒向利用ITOSlit改變電場分佈TFT-LCD顯示器產品特性與規格‧MVA─產生domain的方法：CMO/IDTechConfidentialTFT-LCD驅動原理簡介CMO/IDTechConfidential液晶分子可改變光的極化狀態TFT-LCD驅動原理簡介‧光的偏極化：CMO/IDTechConfidentialTakethe90oTNastheexampleDatafrom：SHARP’swebsiteTFT-LCD驅動原理簡介‧TheOperationPrinciplesofLCD：CMO/IDTechConfidential以90度TN為例資料來源：SHARP’swebsite不管是顯示電極的電壓高，或是Common電極的電壓高，所表現出來的灰階是一樣的，不過液晶分子的轉向卻是完全相反的。TFT-LCD驅動原理簡介CMO/IDTechConfidentialVoltageTransmittance(%)小大電壓越高，穿透的光越少電壓越低，穿透的光越多TFT-LCD驅動原理簡介CMO/IDTechConfidentialDrivingsignal:30Hz,squarewave5v3vTFT-LCD驅動原理簡介‧V-TCurve：CMO/IDTechConfidentialXDarkstate(Off):LCperpendiculartosubstrate.Brightstate(On):LCliesdownandparalleltosubstrate.2046810TFT-LCD驅動原理簡介‧V-TCurve：CMO/IDTechConfidentialV-TcurveofZCM50570%20%40%60%80%100%012345voltagetransmittanceGamma2.20%20%40%60%80%100%0163248grayscaletransmittanceTheengineersinPDcouldonlydeterminethevoltageofgrayscale0,16,32,48,63for6bitsand0,32,64,…,255,etc.for8bits.TheothersaredeterminedbythedatadriverIC.TFT-LCD驅動原理簡介‧Gammavoltage：CMO/IDTechConfidentialV-TcurveofZCM50570%20%40%60%80%100%-5-4-3-2-1012345oddframeevenframe16.67mstime避免DC殘留，造成imagesticking液晶須以AC訊號驅動TFT-LCD驅動原理簡介‧ACDriving：CMO/IDTechConfidentialV-TcurveofZCM50570%20%40%60%80%100%02468pixelvoltagetime16.67msWrongVcomAppliedvoltageshifts所謂的Flicker現象，就是當看液晶顯示器畫面上時，畫面會有閃爍的感覺。這是因為顯示的畫面灰階在每次更新畫面時，會有些微的變動，讓人眼感受到畫面在閃爍。最容易發生在使用FrameInversion的極性變換方式。TFT-LCD驅動原理簡介‧Flicker：CMO/IDTechConfidentialTFT-LCD驅動原理簡介‧TFT-LCD信號寫入原理：CMO/IDTechConfidentialDatalineGatelineITOTFTCstongateDatalineGatelineITOTFTCstoncommonToimprovetheretentioncharacteristicsofthesignalchargeTFT-LCD驅動原理簡介‧StorageCapacitor：CMO/IDTechConfidentialTFT-LCD驅動原理簡介CstITO電極區能夠控制液晶分子排列的區域BM遮進來的區域金屬不透光區A.R.(ApertureRate)=61%(for100μm*300μmpixel)‧Cstoncommon：CMO/IDTechConfidentialVoltage(FeedThrough)=(Vg2-Vg1)*Cgd/Cgd+Clc+CsTFT-LCD驅動原理簡介‧Csoncommon：Common電壓固定不動，造成FeedThrough電壓影響顯示電極的主因只有GateDriver經由Cgd寄生電容所引起的電壓變化。CMO/IDTechConfidential先開啟第一列，其餘關閉。充電第一列至之前設定之所需電壓。TFT玻璃電極DataLineScanLineONOFFOFFOFFOFFTFT-LCD驅動原理簡介CMO/IDTechConfidential接著關閉第一列，電壓已經固定，所以顯示顏色也已固定。開啟第二列，其餘仍保持關閉。充電第二列至預設電壓。依此類推，可完成整個畫面之顯像。ONOFFOFFOFFOFFTFT-LCD驅動原理簡介CMO/IDTechConfidentialPixelDotorSub-pixelDatalineScanlinettTFT-LCD驅動原理簡介‧TFTLCDisplay：CMO/IDTechConfidential++++++++++++++++Frameinversion-----------------Lowerpower-Sensitivetoflickerduetolackofspatialaveraging-Sensitivetohorizontalandverticalcross-talk-V(common)電極可連接在一起.TFT-LCD驅動原理簡介‧LCpolaritycontrol(1/5)：CMO/IDTechConfidential++++----++++----Rowinversion----++++----++++-Higherpower-Reducedflicker-Lowerverticalcross-talk-Sensitivetohorizontalcorsstalk-V(common)電極可連接在一起.TFT-LCD驅動原理簡介‧LCpolaritycontrol(2/5)：CMO/IDTechConfidential+-+-+-+-+-+-+-+-Columninversion-+-+-+-+-+-+-+-+-Lowerpower-Reducedflicker-Lowerhorizontalcross-talk