Home LCD Dead Pixels Choosing LCD Monitors LCD Care Dead Pixel Articles Resources Directory Site Map LCD Dead Pixels: LCD, Liquid Crystal Display or Liquid Crystal on Silicon, has been around for some time. This technology can be commonly found in popular HDTVs, computer or laptop monitors and Sony's new PSP. But the downside to LCD screens is the dreaded "dead pixel" or "hot pixel" phenomenon. Dead pixels or "hot pixels" are defined as "a pixel on an LCD monitor that remains unlit, or black, when it should be activated and displaying a color. [ Read More ] CHOOSING LCD MONITORS When shopping around for an LCD monitor, its features, more than it's appearance, should be your primary concern. Do not be taken in by how good the LCD panel looks. To ensure that the LCD screen is worth buying, you should evaluate these following features carefully: Dead pixels Prolonged or poor use may cause an LCD panel to have "dead pixels" or "hot pixels". A dead pixel is a pixel on an LCD monitor that remains unlit, or black, when it should be activated and displaying a color. A dead pixel occurs when the transistor that activates the amount of light that shows through all three subpixels malfunctions and results in a permanently black pixel. Dead pixels are rare and largely go unnoticed by the user. Ensure that the monitor you are buying does not contain any of these irritating defects. Screen size Like conventional CRTs, the LCD is also measured in terms of its diagonal screen size. For smaller 15" LCDs, you'll typically see 1024x768, for 17" or 18" it is often 1280x1040, while ultra high end models may go as high as 1600x1200. Viewing angle The problem with the LCD film is that this color can only be accurately represented when viewed straight on. But some LCD monitors have wide viewing angles, thereby enabling you to see what's on the screen even if don't view it directly in front of you. However, some people find narrow view angles in notebook computers useful, since they prevent other sitting close to you to see what's on your screen. A theoretical viewing angle of 180 degrees would mean that it is fully visible from any angle in front of the screen. A higher viewing angle is preferred over a lower angle unless you happen to want some security with your screen. Above 120 degree is considered good. Contrast ratio All LCD screens do not emit light on their own but get their brightness from backlighting behind the actual LCD films. A dark screen doesn't mean the backlight isn't working because this light has the tendency to wash out the colors and provide a close approximation on most colors. The contrast ratio is measure of how many brightness levels the LCD can have. Generally, a contrast ratio of over 250:1 is considered good. The higher the contrast ratio of the screen, the better the color representation is by the monitor. When comparing monitors, try to find two models of similar size from the same manufacturer with different contrast ratios. The screen with the higher contrast ratio should have better color.