If your eyes feel gritty, dry, or tired by mid-afternoon, your lighting is likely the culprit. The American Optometric Association defines digital eye strain (computer vision syndrome) as a group of eye- and vision-related problems resulting from prolonged screen use — and lighting is one of its largest, most fixable drivers.

Match screen brightness to the room

Your monitor should be roughly as bright as your surrounding workspace. A screen that's far brighter than the room forces the iris to constantly adjust, fatiguing the focusing muscles. A screen far dimmer than a bright room causes squinting. Test by holding a white document next to the screen — they should look similarly bright.

Eliminate glare, don't add brightness

Position your screen perpendicular to windows, and place task lighting to the side — never directly behind you (which casts screen glare) or behind the monitor (which creates harsh contrast). Use blinds or a sheer curtain to soften direct sun. If you still see the light source reflected in your screen, reposition before reaching for a brighter bulb.

Choose the right color temperature

Cool, blue-enriched light (5000–6500K) supports daytime alertness; warm light (2700–3000K) in the evening reduces circadian disruption. Avoid a single harsh overhead — layer ambient, task, and screen light so no source dominates.

Follow the 20-20-20 rule

Every 20 minutes, look at something 20 feet away for 20 seconds. This relaxes the focusing muscle and restores blink rate, which drops by up to 60% during screen use and is the leading cause of dry-eye symptoms.

When to seek more

Persistent headaches, blurred vision, or eye discomfort that doesn't resolve with breaks and lighting changes may signal a need for a computer-specific eyewear prescription. A small refractive mismatch at reading distance can cause strain that no lighting fix will address.