If you are using an Ubuntu Linux laptop on battery power to read a long PDF or stare at a block of code, you will quickly encounter a highly aggressive power-saving feature. After just a few minutes of not touching the mouse, the screen will violently dim itself, forcing you to wiggle the trackpad to restore the brightness.
While this saves a small amount of battery life, the constant dimming and brightening is incredibly distracting and causes eye strain. Unlike Windows, which puts this setting front and center, Ubuntu hides the screen dimming toggle deep in the Power menu. You can safely disable this automated feature to keep your display at a constant brightness.
How to Safely Disable Ubuntu Automatic Screen Dimming
You must turn off the “Dim Screen” toggle in the central Power settings.
- Click on the system tray in the top-right corner of your Ubuntu screen (where the battery and Wi-Fi icons are).
- Click on Settings (the gear icon) to open the main control panel.
- In the left-hand navigation sidebar, click on Power.
- Look in the “Power Saving Options” section.
- You will see a toggle switch labeled Dim Screen. Click it to turn it Off.
- Directly below that, look at the Screen Blank setting. By default, it might be set to “5 minutes.” If you want the screen to stay on forever while you read, click this dropdown and change it to Never.
Your Ubuntu laptop will now respect your exact brightness slider choice. Even if you don’t touch the mouse for 30 minutes, the screen will remain perfectly bright, allowing you to read long documents without constant interruptions.