Do you still remember the "screen saver" on Windows? When you don't operate the computer for a period of time, you'll see colorful lines changing continuously, 3D pipes extending endlessly, or wandering through a vast maze.

These various animations are not "boring" designs—they really served a practical purpose back then, just as their name suggests: to protect the screen. But most people misunderstand this: it doesn't protect the screen surface from physical scratches, but prevents "screen burn-in".

screen

What is Screen Burn-in?

Essentially, screen burn-in is a phenomenon of "image retention". When a screen displays a static image for a long time, different areas of pixel dots emit light for varying durations, leaving a residual image.

screen burn-in

Burn-in Principle: Uneven Fluorescence Color

In the era when screen savers were prevalent, screens were mainly CRT (Cathode Ray Tube) monitors, which were essentially fluorescent screens coated with phosphor. Their light-emitting principle is that electron beams bombard the phosphor on the screen to make it glow.

However, this mechanism had a problem—"screen burn-in". If the electron beam irradiates the same pixel for too long, the energy will be burned into the phosphor, leaving a permanent faint residual image. It's like a piece of paper: if you always fold it at the same place, a permanent crease will eventually form.

Screen Sver's Role

The solution back then was simple: keep the content displayed on the screen moving, which could largely avoid screen burn-in. That's the significance of screen saver programs. By refreshing constantly changing images and random colors, screen savers prevent excessive wear of fluorescent substances in a single area, just like letting different parts of the screen take turns to "rest", thereby extending its lifespan.

In fact, screen saver programs themselves were a compromise—a necessary software-based fix for the imperfections of the technology at that time. With the development of display technology, CRT monitors have long been obsolete, and the practical function of screen savers has become a thing of the past.

Screen Burn-in Still Exists

Most people's memories of Windows screen savers date back more than a decade, and it seems no one uses them anymore. But the problem of screen burn-in hasn't disappeared.

Today, with the large-scale application of OLED screens, the issue of screen burn-in has returned to public attention. The reason lies in the characteristics of OLED screens.

Pixel "Half-Life"

Each pixel on an OLED screen is an independently glowing organic light-emitting diode, which can be imagined as a whole panel of light bulbs. Since the usage time and brightness of each bulb vary every time the screen is used, the "aging" degree of bulbs in different areas differs after long-term use.

OLED

Areas where bulbs are on for a long time will age faster and become dimmer than surrounding pixels. When the screen displays other images, these pixels with varying aging degrees form residual images. Additionally, the three color pixels (red, green, and blue) may age at different rates, with blue pixels aging the fastest. This causes color balance distortion in frequently lit parts of the screen, resulting in discoloration, which appears to the naked eye as residual images on the screen.

screen

For example, screen burn-in on OLED phone screens—you can faintly see the icon of a certain app no matter where you switch.

Independent glowing pixels allow OLED screens to restore details more accurately, but no matter how excellent the display technology is, it has its shortcomings, and "screen burn-in" is precisely an unavoidable pain point of OLED technology.

How to Avoid Screen Burn-in?

For screens, "screen burn-in" is an irreversible process. Once it occurs, the only repair method is to replace the screen. However, this problem is not unsolvable.

screen burn-in

Technical Intervention: Built-in "Smart Manager"

The areas most prone to screen burn-in are those that often display the same content, such as virtual horizontal lines and the time in the status bar.

The solution is to incorporate an anti-burn-in algorithm into the screen system. Through subtle pixel shifts, these areas are fine-tuned to prevent certain pixels from being in a high-brightness state for a long time, thereby delaying "screen burn-in".

For example, a certain brand of OLED phone screen uses the method of shifting the Home button pixels at specific times to avoid display retention caused by the constant lighting of the button. Usually, this pixel shift is so subtle that it is completely below the threshold of the user's visual perception and does not affect any normal viewing.

Screen Selection: LCD is Naturally Immune to Burn-in

The essence of screen burn-in is uneven pixel aging, and the structure of LCD is completely different.

LCD screens do not emit light themselves; they are provided with light sources by a white backlight panel behind them. The liquid crystal in each pixel deflects as needed to block part of the white light and project the remaining color light.

The liquid crystal layer acts like a blind, controlling the amount of backlight passing through by opening and closing to form images. Whether displaying static or dynamic images, the backlight module always emits light continuously at the same intensity, and the liquid crystal molecules themselves will not fatigue due to displaying static images. In this case, the problem of local screen burn-in naturally does not exist.

For example, iMGS LCD screens, based on the non-self-illuminating display principle, hardly experience screen burn-in.

These two methods correspond to different anti-burn-in ideas: one is algorithm optimization at the software level, and the other is a selection scheme at the hardware level. In commercial usage scenarios, if there is a need to display static images for a long time—such as digital signage, information boards, menu boards, etc.—LCD screens and their derivative technology Mini-LED can eliminate the root cause of screen burn-in in principle.

Products

Featured products

Contact us

What Does "Screen Saver" Actually Protect?