Laptop monitor screen display suddenly shows weird wrong colors: red instead of black, cyan instead of white

Question

Problem description:

My laptop screen suddenly started showing weird colors. What should be black is now red and what should be white is now cyan. However, most colors in between seem fine. Even colors very close to black, white or blue.

If you search for this problem, you'll find many YouTube videos or blog posts about this:

• https://www.hongkiat.com/blog/error-lcd-screen-turns-red-on-laptop/
• https://www.youtube.com/watch?v=HRFbWsbFqNg
• ...

Picture of what it looks like:

To test the colors a little more in detail, I created a HTML file which shows boxes of various colors. With my phone, I took a picture of the screen:

<style>
div {
    margin: 10px;
    width: 50px;
    height: 50px;
    border: 5px solid red;
    font: 32px monospace;
}
span {
    padding-left: 75px;
}
</style>
<div style="background-color: #000000"><span>#000000</span></div>
<div style="background-color: #ffffff"><span>#ffffff</span></div>
<div style="background-color: #ff0000"><span>#ff0000</span></div>
<div style="background-color: #00ff00"><span>#00ff00</span></div>
<div style="background-color: #0000ff"><span>#0000ff</span></div>
<div style="background-color: #0f0f0f"><span>#0f0f0f</span></div>
<div style="background-color: #f0f0f0"><span>#f0f0f0</span></div>

What didn't work:

• The colors are weird even during booting, so it doesn't seem to be an OS-related issue.
• If I connect an external monitor via HDMI, the colors are fine.
• I disconnected and reconnected the flat cable running from the mainboard to the LCD screen but the issue remains.

Answer 1

Assuming this is a hardware defect which cannot be repaired without replacing the mainboard or the LCD screen, and therefore not without significant financial investment: Color calibration can be used as a workaround.

Since the colors very close to the bad colors are displayed properly again, we will try to discard the bad color range. Increasing the minimum and decreasing the maximum values of all colors and therefore slightly reducing the color range, all colors now seem to be inside the color range which can be properly displayed by the screen.

Everything that should be black will now be very, very dark gray - and white will be very, very bright gray. These colors will be displayed properly.

I run Ubuntu Linux and was able to use xcalib to apply this workaround with:

xcalib -clear
xcalib -alter -brightness 2.0
xcalib -alter -contrast 97.0

(I'm sure, there are similar tools for Windows or MacOS, too.)

The change in brightness and contrast is not recognizable or visible to me. However, the workaround is successful and there are no weird wrong colors anymore: