Display Tools

Why use a white screen?

A full white screen can reveal all sorts of display-related issues and defects that are otherwise hard to see: dust and smudges on the panel, uneven brightness, backlight problems, and off-color or discolored patches. It is particularly useful for judging uniformity and color accuracy, because there is nothing else on screen to distract you.

Any inconsistency stands out against a uniform white background, which is exactly what makes these defects easy to spot. Keep in mind that not every monitor shows all of these issues, and their severity varies from panel to panel — a faint imperfection you can only see on a blank white screen is usually nothing to worry about.

What is image retention and burn-in?

Image retention and burn-in are related display issues that can affect certain types of screens, particularly those that use technologies like OLED or plasma. These issues involve the persistence of static images or patterns on the screen even after the content has changed. They differ, however, in permanence and severity:

Image retention, also known as "image persistence", is the temporary one: a faint ghost of previously displayed content stays visible on the screen for a short while. It usually fades on its own as the screen shows new content, or after the display has been off for a bit. The effect is most common in older technologies like plasma, but it can also happen on OLED under the right conditions.
It is generally milder and shorter-lived than burn-in, and it is caused by leaving static content — logos, icons, taskbars — on screen too long without variation. Modern OLED panels fight it with measures like pixel-shifting and automatic screen dimming.

Burn-in is the permanent one, and far more serious. It happens when static images or patterns sit on the screen for so long that the pixels behind them age unevenly and degrade. Those pixels then hold on to the image no matter what is displayed, leaving visible, permanent ghosting.
It is mostly an OLED problem, because there the organic compounds emit light directly and wear out with use. Leave a static logo on an OLED screen for months and the pixels drawing that logo age faster than their neighbors — from then on you can see its outline over any other content. The gray screen above is the easiest way to check: an even gray field makes uneven wear obvious.

What is monitor backlight bleeding?

Monitor backlight bleeding is a visual imperfection that occurs in LCD (liquid crystal display) monitors, where light from the monitor's backlight source escapes through the edges or corners of the screen, leading to uneven and unintended patches of brightness on the display. This phenomenon is most noticeable when displaying dark content or scenes, as the leaked light can cause certain areas of the screen to appear brighter than intended. Backlight bleeding is a side effect of how LCD panels are built, and its severity varies with panel quality and manufacturing tolerances — which is why two monitors of the same model can bleed differently. Use the black screen above to check for it.

What is a dead, hot or stuck pixel?

A dead pixel is a single pixel on the screen that stays unresponsive and does not display any color or light. It appears as a tiny black dot, surrounded by properly functioning pixels. Dead pixels are a common issue in LCD (liquid crystal display) screens, including computer monitors, TVs, and other devices that use similar display technology.

They usually come from manufacturing defects or other problems during production of the LCD panel. Not every stuck-looking pixel is truly dead, though, so it helps to know the difference between the three common defects:

A hot pixel is always lit with a bright color, typically white, no matter what is on screen. Easiest to spot on the black screen.
A stuck pixel stays one specific color (often red, green, or blue) and does not change with the rest of the picture. Easiest to spot on the white screen.
A dead pixel stays completely black and emits no light at all, leaving a small black dot on the screen. Easiest to spot on the white screen, or on any of the colored ones.

People try a few tricks to revive stuck or dead pixels, such as gently massaging the spot or running software that cycles through colors rapidly to stimulate the pixel back to life. These sometimes help with stuck pixels, but a genuinely dead one rarely comes back. If a dead pixel bothers you and your monitor is still under warranty, contact the manufacturer about a repair or replacement — most have a published policy on how many dead pixels a panel is allowed to have.