Pixel problems can affect computers, televisions, and other electronic devices that use digital imaging. Malfunctioning pixels are typically the result of the liquid crystal display (LCD) screen not functioning properly. This can obscure the image on the screen, or make for an annoying nuisance that makes it difficult to read on-screen text. There are many specific types of pixel problems, such as dead pixels, stuck pixels, and partial sub-pixel defects.
In digital imaging, the term pixel refers to a single point in a raster image. It is commonly referred to as a single point in an original digital image. Intensities of pixels usually vary, allowing for the presentation of a wide variety of colors.
Some pixel problems are the result of manufacturing mistakes. Partial sub-pixel defects are a type of pixel problem that usually emerges in production. For example, the RGB film layer in the screen may have been poorly cut or measured. In some cases, this can mean that the entire film layer needs to be replaced in order to resolve the problem.
Two of the most common types of pixel problems are dead pixels and stuck pixels. Many people often confuse the two. A dead pixel, however, typically means that there is a problem with one or more of the three sub-pixels that form a pixel. This can be caused by a manufacturing error or because the computer is not supplying enough power to the screen.
A stuck pixel is usually found on LCD monitors, and is sometimes called a disappearing pixel. For example, on a simple black screen, the stuck pixel distinguishes itself by still having a color. Oppositely, when the screen is illuminated, the dead pixel may be without color. The common causes for a stuck pixel are similar to those of the dead pixel, meaning there is usually either a problem with the computer power supply, or the LCD itself is damaged, likely in the manufacturing process.
There are some common solutions to fix pixel problems. For example, many people rub the screen with a cloth where the defective pixel is located, in an attempt to make it function properly. Others use a heat source, such as a cigarette lighter, to re-energize the screen — however, this method is generally not recommended.
There is also special pixel-fixing software that can be used. These programs generally operate by rapidly turning pixels on and off, with the aim of possibly re-energizing them. Sometimes, simply waiting for the pixel to function again is another strategy. It is generally advised to consult an expert before attempting to 'resurrect' a problematic pixel.