One unfortunate experience that is quite common to smartphone and PC uses is the issue of dead pixels. Each pixel of your LCD screen is made up of three subpixels (red, green and blue), which appear white when turned on and black when turned off. A dead pixel occurs when these three subpixels remain off when you turn them on. This is harder to fix than stuck pixels, which are generated when two or more of the subpixels remain on while the rest are off.
Whether your display has stuck pixels or dead pixels, you can still fix it. The following methods are by no means guaranteed to fix your screen, but they are worth a try at least. In any case, the following tips will educate you on how to fix a dead pixel, whether you need to or not.
HOW TO FIX A DEAD PIXEL IN WINDOWS
PixelHealer is a free application from Aurelitec that is designed to fix pixel problems. On Windows, this is the first app you should try, as it is compatible with many versions of Windows. Once you download the app, it will present you with colored box window and a settings menu. Either click and drag or use the position and size options to place the color box over the area containing the dead pixels. Click on Start Flashing, and try not to look directly at the box, especially if you are sensitive to flashing lights. The window will then start flashing multiple colors very quickly. Leave it on for 30 minutes, then check the pixel again. Basically, you are trying to shock the pixel back to life, forcing a proper response that will have it acting like it should. If this does not work, you can try the iOS fix below, which also works on Windows.
HOW TO FIX A DEAD PIXEL ON IOS
HOW TO FIX A DEAD PIXEL ON ANDROID
First, download the app Dead Pixel Detect and Fix (DPDF). This free app is available for Android 2.3 and later, and it features an interface that is both self-explanatory and easy to navigate. This app lets you cycle through various colors to locate and fix a potentially dead pixel or stuck pixel using an extended series of flashing screens.
FIXING A DEAD PIXEL WITH THE PRESSURE METHOD
If none of the above methods have worked for you, you can try the pressure method. You must be careful, however, as this may cause further problems for your device.
First, locate the problematic area of you screen. Then find a tool with a blunt, narrow edge, preferably the cap of a pen or a corner of a pencil eraser. Now, wrap your tool in a damp, scratch-free cloth. Turn off your screen, then begin to apply pressure to the troublesome area for 5 to 10 seconds, using the wrapped tip. Do this several times. When you finish, try to locate the area filled with dead pixels.
If none of the above methods work, it may be time to replace your display. In the meantime, you now know how to fix a dead pixel, in case the problem comes up again.