Philips 190S9 user manual What are the advantages of TFT LCD compared with CRT?

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FAQs (Frequently Asked Questions)

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 lighting to display images. A TFT LCD has several advantages over a CRT, since it can be very thin and no flickering occurs because it does not use the scanning method.

Q:Why is vertical frequency of 60Hz optimal for an LCD monitor?

A:Unlike a CDT monitor, the TFT LCD panel has a fixed resolution. For example, an XGA monitor has 1024x3 (R, G, B) x 768 pixels and a higher resolution may not be available without additional software processing. The panel is designed to optimize the display for a 65MHz dot clock, one of the standards for XGA displays. Since the vertical/horizontal frequency for this dot clock is 60Hz/48kHz, the optimum frequency for this monitor is 60Hz.

Q:What kind of wide-angle technology is available? How does it work?

A:The TFT LCD panel is an element that controls/displays the inlet of a backlight using the dual- refraction of a liquid crystal. Using the property that the projection of inlet light refracts toward the major axis of the liquid element, it controls the direction of inlet light and displays it. Since the refraction ratio of inlet light on liquid crystal varies with the inlet angle of the light, the viewing angle of a TFT is much narrower than that of a CDT. Usually, the viewing angle refers to the point where the contrast ration is 10. Many ways to widen the viewing angle are currently being developed and the most common approach is to use a wide viewing angle film, which widens the viewing angle by varying the refraction ratio. IPS (In Plane Switching) or MVA (Multi Vertical Aligned) is also used to give a wider viewing angle.

Q:Why is there no flicker on an LCD Monitor?

A:Technically speaking, LCDs do flicker, but the cause of the phenomenon is different from that of a CRT monitor -- and it has no impact of the ease of viewing. Flickering in an LCD monitor relates to usually undetectable luminance caused by the difference between positive and negative voltage. On the other hand, CRT flickering that can irritate the human eye occurs when the on/off action of the fluorescent object becomes visible. Since the reaction speed of liquid crystal in an LCD panel is much slower, this troublesome form of flickering is not present in an LCD display.

Q:Why is an LCD monitor virtually low of Electro Magnetic Interference?

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Contents Philips LCD Monitor Electronic User’s Manual Safety precautions and maintenance Safety and Troubleshooting InformationMaintenance OperationReturn to TOP ServiceGeneral FAQs FAQs Frequently Asked QuestionsWhat is the Auto function? What if I get lost when I am making monitor adjustments?What does the Refresh Rate mean for LCD? Will the LCD screen be resistant to scratches?How should I clean the LCD surface? QCan I change the color setting of my monitor?Can the Philips LCD Monitor be mounted on the wall? Compatibility with other Peripherals Screen AdjustmentsWhat is a USB hub ? What is a Liquid Crystal Display?LCD Panel Technology What are the advantages of TFT LCD compared with CRT? Why is there no flicker on an LCD Monitor?Ergonomics, Ecology and Safety Standards What is the CE mark?Does the LCD monitor conform to general safety standards? Page Troubleshooting Vertical flicker appears Page TCO03 Information Regulatory InformationWaste Electrical and Electronic Equipment-WEEE Recycling Information for CustomersEnergy Star Declaration CE Declaration of ConformityFCC Declaration of Conformity Federal Communications Commission FCC Notice U.S. OnlyEN 55022 Compliance Czech Republic Only Commission Federale de la Communication FCC DeclarationMIC Notice South Korea Only Polish Center for Testing and Certification NoticeVarning North Europe Nordic Countries InformationBsmi Notice Taiwan Only Ergonomie Hinweis nur DeutschlandEnd-of-Life Disposal For customers in Canada and U.S.A Information for UK onlyChina RoHS Return to TOP Other Related Information Information for Users in the U. SInformation for Users outside the U.S About This Manual About This GuideNotational Descriptions Return to TOP Why do I need it? What is it?How to enable SmartImage? Product Information Your LCD monitor SmartImageSmartContrast SmartSharpness SmartSaturateLead-free Product Technical SpecificationsVideo Resolution & Preset ModesFactory preset modes Automatic Power SavingPin Assignment Physical SpecificationsProduct Views Assignment Pin NoTilt Physical FunctionPhilips Flat Panel Monitors Pixel Defect Policy Philips Pixel Defect PolicyProximity of Pixel Defects 190S9 Bright DOT Defects Acceptable LevelReturn to TOP Introduction SmartManage Features and BenefitsPhilips SmartControl Installer Install Shield WelcomeInstaller Install Shield Legal Installer Install Shield Program Files Installer Installation Process Page Page First launch -Wizard Start to useDisplay in Digital Start with Standard pane Adjust menuColor menu Help Menu Optional MenuPlug Ins Menu PIP Example for on line register Theft Deterrence PIN SmartManage Return to TOP Front View Product Description Installing Your LCD MonitorMenu AutoOptimizing Performance Rear ViewResolution Connecting to Your PC Accessory PackReturn to TOP Base Condition Detach the BaseReturn to TOP Page Your LCD Monitor Getting StartedFor Windows Me For Windows Vista Description of the On Screen Display On-Screen DisplayOSD Tree Resolution notification North America Canada USA Customer Care & WarrantyThank you for purchasing this Philips monitor Your Philips F1rst Choice WarrantyJust a click away Just a phone call away F1rst Choice Contact Information Just a click away Your Guarantee in Central and Eastern EuropePhilips Service and Consumer Information Centers Belarus Consumer Information CentersBulgaria Czech RepublicEstonia HungaryLatvia Romania LithuaniaSerbia & Montenegro SlovakiaTurkey RussiaUkraine AntillesChile BrasilColombia MexicoUruguay PeruVenezuela CanadaNEW Zealand AustraliaBangladesh ChinaIndia Hong KongKorea IndonesiaMalaysia PakistanSingapore PhilippinesTaiwan ThailandMorocco South AfricaDubai Your International Guarantee Your Philips F1rst Choice WarrantyUSA Limited Warranty Computer MonitorClick here to access the Warranty Registration Card Before Requesting Service To GET Warranty Service in Canada Just a phone call away Active matrix GlossaryAmorphous silicon a-Si Aspect ratioBrightness Color temperatureCCFLcold cathode fluorescent light ChromaticityContrast ratio Digital Visual Interface DVIEnergy Star Computers Program Gamma IPS In Plane SwitchingGrayscale HueLiquid crystal LCD liquid crystal displayLuminance NitRefresh rate PolarizerSmartContrast SmartControlSmartManage Lite TFTthin film transistorTrueVision Hub USB or Universal Serial BusDevice Vertical refresh rateReturn to TOP Download and Print Installing Your LCD monitor driverDownload instructions Printing instructionsReturn to TOP