Philips 15056 user manual What is polarization ?, How does a TFT LCD Panel work?

Page 38

FAQs (Frequently Asked Questions)

LCD cell is assembled into a 'module' by adding the backlight, driver electronics and frame.

Q:What is polarization ?

A:Polarization is basically directing light to shine in one direction. Light is electromagnetic waves. Electric and magnetic fields oscillate in a direction perpendicular to the propagation of the light beam. The direction of these fields is called the 'polarization direction'. Normal or non-polarized light has fields in several directions; polarized light has a field in only one direction.

Q:What differentiates passive matrix LCDs from active matrix LCDs?

A:An LCD is made with either a passive matrix or an active matrix display grid. An active matrix has a transistor located at each pixel intersection, requiring less current to control the luminance of a pixel. For this reason, the current in an active matrix display can be switched on and off more frequently, improving the screen refresh time (your mouse pointer will appear to move more smoothly across the screen, for example). The passive matrix LCD has a grid of conductors with pixels located at each intersection in the grid.

Q:How does a TFT LCD Panel work?

A:On each column and row of the TFT LCD panel, a data source drive and a gate drive are attached, respectively. The TFT drain of each cell is connected to the electrode. The molecular arrangement of liquid crystal elements differ according to whether it is impressed with voltage or not. It varies the direction of polarized light and the amount of light by letting it through different arrays of liquid crystal elements. When two polarized filters are arranged vertically on a polarized light pole, the light that passes through the upper polarized panel is turned 90 degrees along with the spiral structure of the liquid crystal molecules and goes through the polarized filter at the bottom. When impressed with voltage, liquid crystal molecules are arranged vertically from the original spiral structure and the direction of the light is not turned through 90 degrees. In this case, light that comes through the top polarized panel may not go through the polarized panel at the bottom.

Q:What are the advantages of TFT LCD compared with CRT?

A:In a CRT monitor, a gun shoots electrons and general light by colliding polarized electrons on fluorescent glass. Therefore, CRT monitors basically operate with an analog RGB signal. A TFT LCD monitor is a device that displays an input image by operating a liquid crystal panel. The TFT has a fundamentally different structure than a CRT: Each cell has an active matrix structure and independent active elements. A TFT LCD has two glass panels and the space between them is filled with liquid crystal. When each cell is connected with electrodes and impressed with voltage, the molecular structure of the liquid crystal is altered and controls the amount of inlet

file:///D/My%20Documents/dfu/A5_new/ENGLISH/150S6/safety/saf_faq.htm (6 of 8)2005-06-07 4:49:55 PM

Image 38
Contents Philips LCD Monitor Electronic User’s Manual Safety and Troubleshooting Information Safety precautions and maintenanceService About This Guide Notational DescriptionsReturn to TOP Lead-free Product Product FeaturesTechnical Specifications Scanning Resolution & Preset Modes User definable modesAutomatic Power Saving Physical SpecificationsPin Assignment Pin AssignmentProduct Views Physical FunctionPage Installing Your LCD Monitor Front View Product DescriptionRear View Optimizing PerformanceMore about FPsetup04.exe Description of the On Screen Display OSD TreeOn-Screen Display Return to TOP Customer Care & Warranty Glossary Contrast SUB Gamma IPS In Plane Switching Pixel TFTthin film transistor Hub Vertical refresh rate Page Download and Print Printing instructions Return to TOP FAQs Frequently Asked Questions General FAQsWhat if I get lost when I am making monitor adjustments? What is the Auto function?What does the Refresh Rate mean for LCD? Screen AdjustmentsHow should I clean the LCD surface? Will the LCD screen be resistant to scratches?How do LCDs compare to CRTs in terms of radiation? What is the FPadjust program on the CD-ROM?Compatibility with other Peripherals Can I connect my LCD monitor to any PC, workstation or Mac?What is a Liquid Crystal Display? What is USB Universal Serial Bus?What is a USB hub ? LCD Panel TechnologyWhat are the advantages of TFT LCD compared with CRT? What is polarization ?How does a TFT LCD Panel work? Ergonomics, Ecology and Safety Standards Why is there no flicker on an LCD Monitor?What is the CE mark? Does the LCD monitor conform to general safety standards?Troubleshooting Common ProblemsImaging Problems Green, red, blue, dark, and white dots remains TCO 99 Information WeeeMercury Environmental RequirementsCadmium CFCs freonsCongratulations TCO03 InformationLead ErgonomicsEcology Recycling Information for CustomersEmissions Waste Electrical and Electronic Equipment-WEEE CE Declaration of ConformityEnergy Star Declaration Federal Communications Commission FCC Notice U.S. OnlyCommission Federale de la Communication FCC Declaration EN 55022 Compliance Czech Republic Only Vcci Notice Japan OnlyPolish Center for Testing and Certification Notice MIC Notice South Korea OnlyNorth Europe Nordic Countries Information VarningBsmi Notice Taiwan Only Ergonomie Hinweis nur DeutschlandEnd-of-Life Disposal Information for UK onlyHow to connect a plug Information for Users in the U. S Information for Users outside the U.SPhilips SmartControl SmartManage Features and BenefitsIntroduction Click Philips SmartControl tab SmartManage SmartManage Return to TOP Philips Pixel Defect Policy Philips Flat Panel Monitors Pixel Defect PolicyProximity of Pixel Defects Black DOT Defects Acceptable Level Page Accessory Pack Connecting to Your PCConnecting to Your PC Connecting to Your PC Return to TOP Base Unfold and Fold the Base Unfold the BaseRemove the Base Condition Return to TOP Page For Windows For Windows MeFor Windows XP Dialog box Your Philips F1rst Choice Warranty Just a click away Just a phone call away Page Your Guarantee in Central and Eastern Europe Just a click away Just a phone call away Your International Guarantee Page Your Philips F1rst Choice WarrantyCanada/USA Before Requesting Service To GET Warranty Service in Canada Just a phone call away F1rst Choice Contact Information Czech Republic BelarusBulgaria CroatiaLatvia EstoniaHungary LithuaniaPoland SlovakiaSlovenia RussiaArgentina UkraineAntilles BrasilParaguay ColombiaMexico PeruCanada UruguayVenezuela AustraliaChina NEW ZealandBangladesh Hong KongIndia IndonesiaPakistan KoreaMalaysia PhilippinesThailand SingaporeTaiwan MoroccoSouth Africa Dubai