Psion Teklogix 190V6 user manual Why is there no flicker on an LCD Monitor?

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FAQs (Frequently Asked Questions)

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?

A:Unlike a CRT, an LCD monitor does not have key parts that generate Electro Magnetic Interference, especially magnetic fields. Also, since an LCD display utilizes relatively low power, its power supply is extremely quiet.

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Contents Philips LCD Monitor Electronic User’s Manual Safety precautions and maintenance Safety and Troubleshooting InformationService Notational Descriptions About This GuideReturn to TOP Lead-free Product Product FeaturesTechnical Specifications 190V6Scanning Automatic Power Saving Resolution & Preset ModesPin Assignment Physical SpecificationsPhysical Function Product ViewsTilt Front View Product Description Installing Your LCD MonitorOptimizing Performance ResolutionOSD Tree Description of the On Screen DisplayOn-Screen Display Return to TOP Customer Care & Warranty Glossary Contrast SUB Gamma Nit Refresh rate TFTthin film transistor Device Vertical refresh rate Download and Print Installing FPadjust Program Page General FAQs FAQs Frequently Asked QuestionsWhat is the Auto function? What if I get lost when I am making monitor adjustments?Screen Adjustments Can I connect my LCD monitor to any PC, workstation or Mac? What is USB Universal Serial Bus?Compatibility with other Peripherals How do LCDs compare to CRTs in terms of radiation?What are the advantages of TFT LCD compared with CRT? What is a USB hub ?What is a Liquid Crystal Display? LCD Panel TechnologyWhy is there no flicker on an LCD Monitor? Does the LCD monitor conform to general safety standards? Ergonomics, Ecology and Safety StandardsWhat is the CE mark? Common Problems TroubleshootingImaging Problems Return to TOP Weee TCO 99 InformationCFCs freons Environmental RequirementsCadmium MercuryTCO03 Information Ecology Recycling Information for CustomersCE Declaration of Conformity Waste Electrical and Electronic Equipment-WEEEFederal Communications Commission FCC Notice U.S. Only Energy Star DeclarationCommission Federale de la Communication FCC Declaration Vcci Notice Japan Only EN 55022 Compliance Czech Republic OnlyMIC Notice South Korea Only Polish Center for Testing and Certification NoticeVarning North Europe Nordic Countries InformationErgonomie Hinweis nur Deutschland Bsmi Notice Taiwan OnlyInformation for UK only End-of-Life DisposalHow to connect a plug Information for Users outside the U.S Information for Users in the U. SPhilips Flat Panel Monitors Pixel Defect Policy Philips Pixel Defect PolicyProximity of Pixel Defects Bright DOT Defects Acceptable Level Connecting to Your PC Accessory PackPlug in the cables into connectors Return to TOP Unfold and Fold the Base Unfold the Base BaseRemove the Base Condition Return to TOP For Windows Your LCD MonitorFor Windows XP For Windows MeReturn to TOP 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 Limited Warranty Computer Monitor Before Requesting Service Just a phone call away Page F1rst Choice Contact Information Croatia BelarusBulgaria Czech RepublicLithuania EstoniaHungary LatviaRussia SlovakiaSlovenia PolandBrasil UkraineAntilles ArgentinaPeru ColombiaMexico ParaguayAustralia UruguayVenezuela CanadaHong Kong NEW ZealandBangladesh ChinaIndonesia IndiaPhilippines KoreaMalaysia PakistanMorocco SingaporeTaiwan ThailandDubai South Africa