> People who have myopia or astigmatism also may experience halation (from the word “halo”). Halation occurs when light spreads past a certain boundary, creating a foggy or blurry appearance. In other words, white letters can appear to bleed into a black background, making it more difficult to read, especially if the print is fine.
https://www.allaboutvision.com/digital-eye-strain/is-dark-mo...
