Philips HWS8220Q user manual Why is there no flicker on an LCD Monitor?

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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?

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 220BW8 Safety precautions and maintenance Safety and Troubleshooting InformationDon’t Installation LocationsGeneral FAQs General FAQsWhat does the Refresh Rate mean for LCD? Can the Philips LCD Monitor be mounted on the wall? Screen AdjustmentsCan I connect my LCD monitor to any PC, workstation or Mac? Compatibility with other PeripheralsWhat are the advantages of TFT LCD compared with CRT? LCD Panel TechnologyWhy is there no flicker on an LCD Monitor? Ergonomics, Ecology and Safety Standards Common Problems TroubleshootingPress the Auto button Imaging ProblemsGreen, red, blue, dark, and white dots Energy 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 DeclarationPolish Center for Testing and Certification Notice Vcci Notice Japan OnlyMIC Notice South Korea Only North Europe Nordic Countries Information Ergonomie Hinweis nur Deutschland Bsmi Notice Taiwan OnlyInformation for UK only End-of-Life DisposalWaste Electrical and Electronic Equipment-WEEE Green & Yellow Earth EChina RoHS Information for Users outside the U.S Information for Users in the U. SAbout This Manual Return to TOP SmartImage Lite Selective Models Product FeaturesSmartResponse Selective Models Product Lead-free Product Technical SpecificationsAudio Selective Models Resolution & Preset ModesFreq kHz Resolution Automatic Power SavingPin Assignment Physical SpecificationsFront View Product Description Product ViewsTilt Swivel Height adjustment Philips Flat Panel Monitors Pixel Defect Policy Philips Pixel Defect PolicyProximity of Pixel Defects Model SmartManage Features and Benefits IntroductionPhilips SmartControl Page Page Return to TOP Page Rear View Connecting Front View Product DescriptionOptimizing Performance Connecting to Your PC Accessory PackCable management 4Connect to PC Return to TOP For Windows Your LCD MonitorFor Windows XP For Windows MeFor Windows Vista OSD Tree Description of the On Screen DisplayOnly available for Europe Model Only available for Nafta Model Only available for Asia Pacific Model Return to TOP Customer Care & Warranty Your Philips F1rst Choice Warranty Just a click away Just a phone call away F1rst Choice Contact Information Your Guarantee in Central and Eastern Europe Just a phone call away Consumer Information Centers Bosnia & Herzegovina Croatia Lithuania Latin America Chile Canada Bangladesh Indonesia Pakistan Middle East Your International Guarantee Page Limited Warranty Computer Monitor Before Requesting Service Just a phone call away Glossary SUB Digital Visual Interface DVI Gamma Nit Refresh rate SmartTouch controls USB or Universal Serial Bus Download and Print FPsetup4.3.exe Installing FPadjust Program
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