A weird black dot is probably one of the most frustrating things you can run into when buying a new screen. This, dear readers, is a dead pixel. Why it happens and what you can do about it.
What causes dead pixels?
Before proceeding to fix dead pixels, it is important to understand how pixels work in a monitor. The basic technology that drives the monitor is the liquid crystal display or LCD for short.
How two polarizing filters work to sandwich a layer of liquid crystal is the name given to a type of liquid that may also reflect the properties of the crystal. Behind this sandwich is a backlight that provides a source of light that you can see with your monitor. As that light passes through the sandwich, each layer is converted using electrons to produce either light, no light, or some inclination between the two. At the individual level, these are called electrodes and are the building blocks of the LCD monitor.
If you want to extract color from your LCD you add. one more Three layers of filters – usually red, green and blue. Again, by adjusting the number of electrons going into each color of the filter, you can increase or decrease the color and intensity, thus giving you a specific RGB value that your eyes interpret as color. Therefore, each pixel is made up of three different electrodes, one for each color.
When you have a problem with a pixel, the main reason is that one or more electrodes of that pixel are getting damaged in some way.
Types of pixel defects: stuck, hot, and dead
Okay, so you know how pixels work and you have a dead one – but, do you really have a dead pixel? There are various pixel issues you may encounter. If you’re lucky, you’re not working with Dead Pixel.
For example, one of the most common defects is a “stuck pixel”. Thankfully, there are some things you can do to help fix stuck pixels.
Another drawback is the “hot pixel”, which is a pixel that is always bright. This is because the electrodes behind it allow all light to pass through, regardless of what is on the screen. Conversely, a fault is called a dark spot, where light does not pass, although the fault is slightly lower.
After all, we have the dead pixel, and this is the real killer because it means that the electrodes behind the pixel have completely failed.
Can you fix dead pixels?
Unfortunately, as a user, you have no direct way to fix a dead pixel because it is a manufacturing error or transportation issue 99% of the time. At the moment, the only option you have is to look at the warranty that comes with your screen and see if the dead pixels are covered.
Ultimately, this may vary depending on the manufacturer and the class of your screen. For example, Class I monitors do not allow any dead pixels, so the manufacturer will replace them with the perfect one.
Class III monitors, on the other hand, allow 15 dead pixels and three clusters of trapped pixels. If your dead pixel issue is not serious enough, it will not be covered by your manufacturer’s warranty.
Interestingly, sometimes manufacturers take these bad screens and sell them on a large scale at low prices. This is a great way to recycle products for use where dead or stuck pixels won’t cause as much of a problem, as in industrial processes or server rooms where graphical quality isn’t essential.