iPhone’s new “dark mode”; is it really better for your eyesight?

Daniel Hardiman-McCartney FCOptom, who is the College of Optometry’s  Clinical adviser, has been researching into Apple’s new dark mode for iOS 13. He notes that although this new dark mode may save battery life, despite tech folk law, it is unlikely to save you from digital eye strain.

He explains that claims that dark mode is better for your eye sight are controversial despite much media attention. Night mode may be useful by reducing the overall screen brightness and being optimised for use in low light environment, but there is little evidence available to say whether it is effective at reducing digital eye strain.

Daniel notes that the potentially damaging effects of white-background screens, are usually referring to the “blue light,” part of the light spectrum made of short, high-energy wavelengths. A study published in BMJ Ophthalmology noted that blue light could be a factor in eye tiredness, but lists a number of other factors that are also likely to contribute to digital eye strain. 

Despite people’s concerns, there is no evidence that screen use can damage our eyes. The benefits of using a screen over paper are that the size, brightness and contrast of the screen display can all be altered. However, some people find that looking at a screen for a long time is tiring. Using either a dark mode or night shift can be helpful when using a device at night. If you’re affected by eyestrain, then here are some extra pieces of advice from Daniel:

Here are some ways to look after your eyes while using your screen:

  • Apply the 20-20-20 rule – every 20 minutes look at something 20 feet away for 20 seconds. That will give your eye muscles a rest.
  • Try to blink regularly. Focusing on a screen may make you blink less, which may make your eyes dry and uncomfortable.
  • Position your device screen so that:
    • it is between 40 and 76 centimetres (16 to 30 inches) from your eyes
    • it is below the level of your eyes
    • there are no distracting reflections, e.g. from a light or window.
  • Use a text size that is easy to see.
  • Have regular sight tests.
  • Wear glasses if you have been prescribed them.
  • If you are affected by dry eye, consider using lubricating eye drops.