Cybernet offers a 1-year warranty for defective pixels that meet the following criteria: 5 bright sub-pixels, 7 dark sub-pixels, or a combination of 7. This is because a pixel usually is not dead, and may be fixable. The following information is recommended for advanced users only. It is provided as a courtesy, and no warranty for any of the below methods is expressed or implied. The following information is from Wikipedia and wikiHow
Defective pixels are pixels on an LCD screen not performing as expected; the pixel is failing to reproduce light levels correctly. ISO 13406-2 distinguishes between three different types of defective pixels:
- Hot pixels (always on)
- Dead pixels (always off)
- Stuck pixels (one or more sub-pixels are always on or always off)
A permanently lit (white) pixel is called a hot pixel. Hot pixels are usually best seen against a dark background. A dead pixel is a defective pixel that remains unlit. Dead pixels are usually best seen against a white background. A stuck pixel will usually be most visible against a black background, where it will appear red, green, blue, cyan, magenta, or yellow. The most common stuck pixel will be red, green, or blue. Each pixel on an LCD monitor is composed of three sub pixels, one red, one green, and one blue, which produce the visible color of the pixel by their relative brightness. A stuck pixel results from one or more of these sub-pixels being permanently turned on or off. Stuck pixels are not guaranteed to be correctable, and can remain faulty for the life of the monitor. A stuck pixel might be fixed with software methods (see resources below). Stuck pixels are often incorrectly referred to as dead pixels, which have a similar appearance. In a dead pixel, all three sub-pixels are permanently off, producing a permanently black pixel. Dead pixels can result from similar anomalies as stuck pixels, but may also occur from a non-functioning transistor resulting in complete lack of power to the pixel or. Dead pixels are much less likely to correct themselves over time, and typically cannot be repaired through any of several popular methods.
The most popular method for repairing a stuck pixel is to try running pixel fixing software. Stuck pixels can often be re-energized by rapidly turning them on and off. If this fails, try applying pressure to the pixel. First turn off the monitor, then get a damp cloth so the screen doesn't get scratched. Take a ballpoint pen, small screwdriver, or some other sort of instrument with a focused but relatively dull point. A very good tool would be a PDA stylus. Fold the washcloth to ensure it is not accidentally punctured, and apply pressure through it to exactly where the stuck pixel is. Try not to put pressure anywhere else, as this may make more stuck pixels. While applying pressure, turn on the monitor. Remove pressure and the stuck pixel should be gone.
(This works as the liquid in the liquid crystal has not spread into each little pixel. This liquid is used with the back light on the monitor, allowing different amounts of light through, which creates the different colors.)
A similar method is to tap the stuck pixel. Make sure the LCD monitor is on, and display a black image. Any background that allows the pixel to be clearly seen is perfect. Be sure the monitor is on, as the LCD back light needs to be illuminating the panel. Find a marker with a rounded cap or a pencil eraser as a tapping tool. Use this tool to gently tap where the stuck pixel is. Tap lightly at first, just enough to see a quick white glow under the point of contact. If there was no white glow, use just slightly more pressure. Start tapping gently. Increase the pressure on the taps gradually for 5-10 taps until the pixel rights itself. Display a white image to verify that more damage has not been caused and the pixel has been fixed. If the pressure and tapping methods don't work directly on the stuck pixel, start moving outward around it. If the pixel flickers while doing this then focus the pressure and tapping techniques at this point instead. Please note that pressure methods do not work on a Touch-enabled i-One-series All-in-One PC.
Many people report success with these techniques but these instructions won't work in every case. It may take a few attempts to ensure the stuck pixel is being pressed exactly. These instructions will fix stuck pixels, not dead ones. Do not attempt to open the monitor as it will void the warranty. Do not allow any electrical equipment to become wet or it may break. Some people claim that touching the screen can cause more pixels to become stuck, though this has not been proven. Be prepared to suffer a complete loss; the glass may crack when tapping or putting pressure on an LCD assembly.
Links and other resources -
- An animated gif that may fix dead pixels is available for download from this article (deadpixel.gif)
- UDPixel 2.2 - A free windows application which help you to locate and fix 1 or more stuck pixels.
- DPT (Dead Pixel Tester) - A Windows application to help locate and identify dead/stuck pixels. Also has a pixel exerciser built in to possibly get lazy pixels working again.
- Dead Pixels Test (web-based)http://www.gdargaud.net/Hack/DeadPixels.html#LCD
