The Liquid Crystal Display [LCD] technology in a monitor uses a liquid crystal solution between two sheets of polarizing material, which align the crystals when an electric current is passed. Pixels are the vertical and horizontal dots that form the images displayed on an LCD monitor. Each pixel is further divided into three sub-pixels for red, green and blue light. A 1280 x1024 resolution LCD monitor typically has approximately 3.9 million sub-pixels.
Now, there are three different types of defective pixels.
1. Hot pixels: is a permanently lit (white) pixel. This type of defective pixel is best seen in dark background.
2. Dead Pixel: is the opposite of a Hot Pixel. This type remains unlit and is best seen In a white background.
3. Stuck Pixel: is usually visible against a black background. It will appear red, green, blue, cyan, magenta, or yellow although stuck red, green, or blue pixels are most common. As mentioned above, each pixel is composed of three subpixels, one red, one green, and one blue, which produce the visible color of the pixel by their relative brightness. A stuck pixel results from a manufacturing defect, which leaves one or more of these sub-pixels permanently turned on or off.
How to fix:
I found a couple of tools that you can use and might help you fix these stuck or defective pixels. One is from JScreen Fix which runs a java applet that helps fix stuck pixels and image persistence on LCD screens and reduces burn-in on plasma screens. It randomly turns on and off each pixel at up to 60 times a second to fix stuck pixels. Another is from Killdeadpixel that will try to fix the defective pixels by using this graphic.
The graphic will try to massage the dead pixel back alive again by getting it to change rapidly.
It has been reported to work many times.
But it doesn’t work for all dead pixels… Still it’s a good try.
If after 1 hour it doesn’t work, please use the full screen version below and try for about 12hours.
These tools may not always work, but before sending your LCD Monitor back to the manufacturer, you might want to give them a try.