When your screen has cracked, it is extremely vulnerable. A result of this vulnerability can be that the OLED, the part that makes the screen whole, also gets damaged. Causing black and/or blue and purple spots to show on the screen. If an individual pixel has been damaged, it will stay turned off and appear black.
Tap the Display & Text Size. Look at the bottom of your screen and find the option labeled Reduce White Point. If the setting is turned on (the slider is green), turn it off by tapping the slider to the right of the option. The brightness level of your screen should then return to normal.
Your iPhone screen can be black due to two settings – Dark Mode or Color Invert. To make the screen normal, go to iPhone Settings > Display & Brightness and choose Light. Also, turn off the switch for Automatic.
Try Turning Off Auto-Brightness To turn off Auto-Brightness, open Settings and tap Accessibility -> Display & Text Size and turn off the switch next to Auto-Brightness. Keep in mind that turning off Auto-Brightness can make your iPhone's battery drain faster.
Click and hold on the slider next to "Display sleep" and drag it to the right to increase the amount of time before the display goes to sleep. You can set it anywhere from 1 minute to 3 hours or "Never.
A basic power-saving plan will, by default, immediately dim the laptop's screen in order to save power when your computer is running on battery. Your screen going dim could be as simple as that -- the power cord connecting the laptop to the wall isn't connected properly, and the computer is running on battery.
Some televisions have a Light Sensor function, which causes the picture to change brighter or darker based on the lighting conditions in the room. It may be possible to enhance picture brightness by turning off the Light Sensor or Automatic Brightness Control (depending on your TV model).
Why Your iPhone Keeps Dimming. Most of the time, your iPhone keeps dimming because Auto-Brightness is turned on. Auto-Brightness is a feature that automatically adjusts the brightness of your iPhone screen depending on the lighting conditions around you.
Make Sure Zoom Isn't On If you recently used the Zoom feature in Settings -> Accessibility -> Zoom and left it on accidentally, it may be the reason why your iPhone screen is too dark! Using the Zoom setting, you can actually make the iPhone display darker than you're able to with the Brightness slider.
Apple says its iOS devices use an ambient light sensor to automatically adjust brightness levels based on the light conditions in your surroundings. You can see this in action if you keep your eyes on the brightness slider, which will move according to those light conditions.
Open Settings and tap Display & Brightness. Drag the slider under Brightness to the right to increase the brightness of your iPhone. If your iPhone is still too dark, it's time to look at a new setting that Apple introduced with iOS 10: Reduce White Point.
1. Turn off auto-brightness: If your brightness levels keep fluctuating all the time, then you might want to ensure that auto-brightness is off if you haven't already. This can be done through Settings > Accessibility > Display & Text Size > Auto-Brightness.