In addition to adjusting the screen brightness on the OnePlus smartphone manually, we can also enable the adaptive display brightness.
Here, the OnePlus device automatically regulates the brightness and adapts to the given lighting conditions of the environment.

This setting is especially recommended because the screen, or rather its brightness, is one of the biggest battery consumers and thus battery capacity can be saved.

Note: If the automatic or adaptive brightness is enabled, we can readjust the screen brightness at any time by means of the slider. This is done either in the display settings as also in the quick settings of the status bar.

Android 10 | OxygenOS 10.0
Adaptive brightness -  Open the  Settings
Adaptive brightness -  Tap on  Display
Adaptive brightness -  Enable or disable  Adaptive brightness
  1. Open the Settings
  2. Tap on Display
  3. Enable or disable Adaptive brightness

OnePlus Instructions