Philips 150V5 user manual FAQs Frequently Asked Questions

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FAQs (Frequently Asked Questions)

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 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.

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Contents Philips LCD Monitor Electronic User’s Manual Safety precautions and maintenance Installation LocationsReturn to TOP About This Guide Notational DescriptionsReturn to TOP Product Information Video User definable modes Physical Specifications Product Views Physical Function Front View Product Description Rear ViewOptimizing Performance On-Screen Display Description of the On Screen DisplayMaking adjustments in the OSD menu Auto Setup Making adjustments in the Management submenu On-Screen Display Making adjustments in the Clock/Phase submenu Use Making adjustments in the Color submenu On-Screen Display Making adjustments in the OSD submenu UseTo revert to factory settings, follow these steps Factory RecallSelecting your preferred language To exit and clear the OSD Menu Customer Care & Warranty Glossary Energy Star Computers Program Vertical refresh rate Download and Print Return to TOP FAQs Frequently Asked Questions General FAQsFAQs Frequently Asked Questions Screen Adjustments Compatibility with other PeripheralsLCD Panel Technology FAQs Frequently Asked Questions Ergonomics, Ecology and Safety Standards Common Problems Imaging ProblemsVertical flicker appears Troubleshooting CE Declaration of Conformity Energy Star DeclarationFederal Communications Commission FCC Notice U.S. Only Commission Federale de la Communication FCC DeclarationBsmi Notice Taiwan Only Ergonomie Hinweis nur DeutschlandEnd-of-Life Disposal For customers in Canada and U.S.AInformation for Users in the U. S Information for Users outside the U.SPhilips Pixel Defect Policy Philips Flat Panel Monitors Pixel Defect PolicyProximity of Pixel Defects Black DOT Defects Acceptable Level Accessory Pack Connecting to Your PCReturn to TOP Connecting to Your PC Getting Started For Windows XP Return to TOP Your International Guarantee International Guarantee