Set screen brightness
You can change the brightness of your screen to save power or to make the screen more readable in bright light. You can also have the screen dim automatically when on battery power and have it turn off automatically when not in use.
Set the brightness
Click the icon at the very right of the menu bar and select System Settings.
Select Brightness and Lock.
Adjust the Brightness slider to a comfortable value.
Many laptop keyboards have special keys to adjust the brightness. These have a picture that looks like the sun and are located on the function keys at the top. Hold down the Fn key to use these keys.
Select Dim screen to save power to have the brightness automatically lowered when you're on battery power. The backlight of your screen can take a lot of power and significantly reduce how long your battery will last before it needs to be recharged.
The screen will automatically turn off after you haven't used it for a while. This only affects the display, and doesn't turn off your computer. You can adjust how long you have to be inactive with the Turn screen off when inactive for option.