Most people consider overhead and ambient lighting to be the biggest factor when it comes to light sensitivity. The light that computer and device screens emit can be just as troublesome. The way the screens are lit and how they perform when dimmed can affect how you feel.

Most of the screens we look at are either LCD or LED-lit LCD (which people call “LED screens”).

LCD Screens

LCD screens are backlight by a fluorescent bulb – and they have the same issues as any other sort of fluorescent light. Dimming LCD screens can helpful, since the less intense the light from a fluorescent is, the less intense the invisible flicker is. Screens that are too dark can cause eyestrain, so be sure you find a comfortable balance.

LED Screens

LED-lit LCDs are, unsurprisingly, lit by LEDs. LEDs can only be completely on or completely off. To simulate any brightness less than 100%, they must pulse on and off. Dimming these screens causes an invisible flicker that is otherwise not an issue with most LED screens. Just like with fluorescent lights, the flicker is undetectable to the human eye, but the brain can still pick it up and make you feel ill.

If you have an LED-lit LCD that bothers you try keeping the brightness at 100%. If that's uncomfortably bright, try adjusting your computer’s white balance to make the light warmer or use a program like f.lux, which automatically changes the white balance according to the time of day.

Whether your screens are LCD or LED, Indoor TheraSpecs help manage your screen-related symptoms.

Reference:

• Sun J. Pulse width modulation. In Vasca F & Iannelli L (Eds.), Dynamics and control of switched electronic systems. 2012. Springer-Verlag: London.