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

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FAQs (Frequently Asked Questions)

A:A Liquid Crystal Display (LCD) is an optical device that is commonly used to display ASCII characters and images on digital items such as watches, calculators, portable game consoles, etc. LCD is the technology used for displays in notebooks and other small computers. Like light-emitting diode and gas-plasma technologies, LCD allows displays to be much thinner than cathode ray tube (CRT) technology. LCD consumes much less power than LED and gas-displays because it works on the principle of blocking light rather than emitting it.

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: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

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Contents Philips LCD Monitor Electronic User’s Manual Safety and Troubleshooting Information Safety precautions and maintenanceInstallation Locations Page FAQs Frequently Asked Questions General FAQsWhat does the Refresh Rate mean for LCD? What if I get lost when I am making monitor adjustments?What is the Auto function? Will the LCD screen be resistant to scratches?QCan I change the color setting of my monitor? Screen AdjustmentsHow should I clean the LCD surface? What is the FPadjust program on the CD-ROM?Can I connect my LCD monitor to any PC, workstation or Mac? Compatibility with other PeripheralsHow do LCDs compare to CRTs in terms of radiation? Are Philips LCD monitors Plug-and-Play?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 the CE mark? Ergonomics, Ecology and Safety StandardsWhy is there no flicker on an LCD Monitor? Does the LCD monitor conform to general safety standards?Page Troubleshooting Common ProblemsImaging Problems Return to TOP CE Declaration of Conformity Energy Star DeclarationFederal Communications Commission FCC Notice U.S. Only OFFFCC Declaration of Conformity Commission Federale de la Communication FCC DeclarationEN 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 For customers in Canada and U.S.AInformation for UK only EarthedWaste Electrical and Electronic Equipment-WEEE China RoHS Information for Users in the U. S Information for Users outside the U.SAbout This Guide Notational DescriptionsReturn to TOP SmartImage Lite Product Features190X7 IntroductionSmartResponse How to enable SmartImage LiteWhy Need it? There are six modes to be selectedWhere will it be effective? Technical SpecificationsHow to use it? Lead-free ProductScanning Resolution & Preset Modes Factory preset modesAutomatic Power Saving Physical SpecificationsPin Signal Assignment Pin AssignmentProduct Views Physical FunctionTilt Philips Pixel Defect Policy Philips Flat Panel Monitors Pixel Defect PolicyProximity of Pixel Defects Black DOT Defects Acceptable Level Perfect Panel Warranty Introduction SmartManage Features and BenefitsPhilips SmartControl Click Philips SmartControl tab SmartManage SmartManage Return to TOP Installing Your LCD Monitor Front View Product DescriptionVolume Rear ViewMore about FPsetup4.3.exe Optimizing PerformanceReturn to TOP Accessory Pack Connecting to Your PCCable management Return to TOP Your LCD Monitor For WindowsFor Windows Me For Windows XPFor Windows Vista Description of the On Screen Display OSD TreePage Page Page Return to TOP Customer Care & Warranty Your Philips F1rst Choice Warranty Just a click away Just a phone call away Your Guarantee in Central and Eastern Europe Just a click away Just a phone call away Your International Guarantee Limited Warranty Computer Monitor Before Requesting Service Just a phone call away F1rst Choice Contact Information Bulgaria BelarusAstline Czech RepublicEstonia Bosnia & HerzegovinaCroatia HungarySerbia & Montenegro Macedonia LithuaniaRomania SlovakiaRussia SloveniaPoland TurkeyBrasil AntillesArgentina ChilePeru MexicoParaguay UruguayAustralia VenezuelaCanada NEW ZealandHong Kong BangladeshChina IndiaKorea IndonesiaMalaysia Singapore PakistanPhilippines TaiwanSouth Africa ThailandMorocco DubaiGlossary Contrast SUB Gamma IPS In Plane Switching Pixel SmartTouch controls USB or Universal Serial Bus Download and Print Installing FPadjust Program