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Flat-Panel Blur - Begone!
by chris

How could an LCD display possibly be blurry or out of focus?
The popularity of flat screen monitors continues to grow. These desktop versions of laptop LCDs use less power than a CRT (Cathode Ray Tube) display of the same size, and provide high-contrast brilliant color images all in a slim, high-tech package. Just as features and styles vary from vendor to vendor, the appearance and quality of the displays will also differ. But if you have a new flat screen display that does not appear to be as sharp and clear as the CRT it replaced, take a moment to check the basic settings. For the best possible video display, you will have to check both your computer's display settings and the flat panel display settings.

Make sure the computer's display settings are set to the maximum resolution the flat panel screen supports. The maximum resolution of the flat panel display is called the "Native Mode" of the display and will provide the clearest, sharpest possible match between the physical configuration of the LCD panel and your video card's signal.

Native mode
Early LCD displays had a single group of one red, green, and blue dots or pixels physically in the display that could be addressed by the display adapter in the computer. If a flat screen display had 1024 groups of RGB elements across the display and 768 elements from top to bottom, then the native resolution of the display is 1024x768. When you set the video display for any resolution other than 1024x768, the number of elements being displayed does not match the number of elements physically available in the screen. This results in a jagged or blocky appearing image on your screen. A CRT has several groups of RGB elements that are used to display a single pixel from the display adapter even at higher resolutions. Because more groups are used in the CRT display, the resulting image will appear much sharper. Flat panel displays no longer use just one group of RGB elements in the display for each pixel, meaning that they do a much better job of displaying your work - even at resolutions other than the optimal "native mode" of the display. Every flat panel screen has an optimal resolution where the image will appear the sharpest; refer to your documentation for this resolution, then adjust your display properties to this setting.

If the video display adapter properties are already set to the optimal mode for the display, and the image still appears blurry or out of focus, then the problem is most likely that the flat panel display is out of adjustment. While you could manually alter the display width, height, horizontal and vertical position of the image, most displays have an automatic adjustment feature.

Flat panel display adjustments
Like CRT displays, a flat screen monitor will have several adjustments that you can make using the buttons or On-Screen-Display (OSD). While many of the displays now auto-configure to your video signal when powered on or when the settings change, not all of the displays will. You should be aware that this feature is not tied to any one manufacturer, price range, or screen size. But even if a display does not auto-configure automatically, most will have this feature available in the On-Screen-Display menus where you can manually start the process. The auto-configure feature should adjust the display width and height out to the physical edges of the display. There is no wasted space on an LCD display unlike a CRT that uses a shadow mask or where the picture tube extends behind the plastic bezel of the screen. "Auto Adjust" may also change your backlight brightness, display contrast, and color correction from the available display settings supported.

While it does not directly affect the sharpness, flicker can be annoying in your display. Refresh rates of 60 Hertz and less are the most common reason for flicker. Whether you have a choice in adjusting this may be a limitation of the display adapter, the flat panel monitor, or both. Some flat panel monitors only operate at a 60Hz refresh rate, however most new displays can support 70, 72, or 75Hz refresh rates. But it is your video adapter that must produce the signal for the monitor, and this is what must be adjusted to the higher refresh rate to benefit. In Windows, enter Display properties from the control panel or by right-clicking on the desktop and selecting "properties," click on the "properties" tab then click on "advanced." Examine the monitor settings for refresh rate, although this should have been tied to the Plug-And-Play capabilities when the monitor was detected. You can try adjusting the refresh rate manually to see if this reduces flicker, although you may have to repeat the Auto-Adjust process if you make changes.

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