Blue-light glasses: what they can (and cannot) do

Our screens emit a peak of blue-violet light between 400 and 455 nm. Blue-light lenses reflect or absorb part of that band and usually add an anti-glare coating, which is why many people find them more comfortable for long screen sessions.

What the filter does

• Filters up to 40% of blue-violet light (400–455 nm) — the faint violet reflection you see on the lens.
• Reduces glare from screens and overhead lighting thanks to the anti-reflective coating.
• Adds a very faint warm tint that most people stop noticing within minutes.

What it does not do

Digital eye strain mostly comes from focusing at one distance and blinking less. Blue-light lenses are not a medical treatment, so pair them with good habits:

• Follow the 20-20-20 rule: every 20 minutes, look at something 20 feet away for 20 seconds.
• Keep your screen an arm’s length away and slightly below eye level.
• Get an eye test every two years — uncorrected prescriptions cause most strain.