TECHNICAL NOTEOptimize Structured LCDBacklight Components-Accurately and QuicklyWith TracePro'Opto-Mechanical Design Software's Textured RepTileTMOptimization UtilityTracePro's Textured RepTile Optimization Utility helps users optimize structured Liquid Crystal Display(LCD)back-light components including Brightness Enhancement Films(BEFs),Turning Films,and extraction features in light-guides.With a TracePro model of the LCD,the utility generates and optimizes a Textured RepTile surface property foruniformity or flux.While useful for optimizing structured backlight components,this tool can also be used to opti-mize any Textured RepTile in TracePro.The utility requires the most recent release of TracePro Expert 4.1.The setup files and instructions for installation ofthe Textured Reptile Optimization Utility may be downloaded:http://www.lambdares.com/technical_support/tracepro/early_access/.Liquid Crystal Displays(LCDs)There are many types of LCDs differing in performance characteristics-brightness,color,viewing angle and contrast.Optical,electrical and mechanical engineers have an extensive toolbox of component and film alternatives when designingthe LCD panel,its front surface films,and its backlight.BacklightCourtesy of 3M CorporationPredictive modeling of LCDs and LCD components with TracePro opto-mechanical design software enables adherence toperformance,consistency and cost,without the cost and time associated with iterative hardware prototyping-including thevery high costs of batch processing thin films,polymers,and semiconductor materials.Predictive Modeling of LCDsTraceProTracePro is a comprehensive,versatile software tool for modeling the propagation of light in opto-mechanical systems.Models are created by importing design files from a lens design program or a CAD program or by directly creating thesolid geometry in TracePro.Optical and mechanical properties are applied to materials and surfaces.Source rays propagateLambdaResearchTraceP'Page 1www.lambdares.comTECHNICAL NOTEOptimize Structured LCD Backlight Componentsthrough the model with portions of the flux of each ray allocated for absorption,specular reflection and transmission,phosphorescence,and scattering.From the model,analyze:Light distributions in illumination systemsLumens exiting,absorbing,and incident at the component and system levelsStray light,scattered light,and aperture diffractionThroughput,loss,or system transmittanceFlux or power absorbed by surfaces and bulk mediaPolarization effectsBirefringence effectsCIE plots and Candela distributionsOptical efficiency,luminance and radiance metricsFluorescence effects of phosphors in white light LEDsModeling LCD ComponentsLCD PanelsAn LCD panel consists of a liquid crystal sandwiched between two polarizers.By varying the voltage applied to the liquidcrystal in combination with the polarizers,varying shades of grey pixels are created.With the addition of a color filter,eachred,green and blue subpixel is individually controlled,allowing varying amounts of red,green,and blue.In addition to the spectral throughput characteristics of filters,TracePro has the ability to accurately model the polarizationextinction ratio,the absorbance,and the temperature dependence for the breadth of polarizers used in LCDs including iodineand organic dye stained polyvinyl alcohol(PVA),chemically altered PVA and wire grid.■Gid5 ource■Apply PropertiesMPPL_04Moxtek wire grid polarizer databasepolarization statePage2TECHNICAL NOTEOptimize Structured LCD Backlight ComponentsTracePro's Polarization Maps map the polarization ellipse for the incident flux on to any selected surface in the model.Polarization Map for Incident FluxObject 1 Surface 1nen of PolObject 1 Surface 01.0005.0.482.1.17)05.0.482.1.170.950.900.850.75口口0.600.550.500.450.400.150.100.050.050.000.00Polarization map:linear at 45 degreesPolarization map:circular polarizationFront Surface FilmsFront surface films may be applied to an LCD panel to enhance its performance-anti-glare coatings that scatter light and anti-reflective films that reduce reflections improve the readability under brightly lit conditions-and privacy films that control thedirection of light make images visible only from direct viewing angles.TracePro has the ability to accurately model films by either specifying the thin film stack layer prescription or specifying thereflection,transmission,absorption for each wavelength,incident angle,polarization,and temperature.Thin Film Stack Editor0.0912CoatingMgF20.125Coating0.0769CoatingSUBSTRATETableThin Film Stack Editor:3 layer anti-reflection coatingPage 3