Eye Strain

Burning eyes, headaches, blurry vision at the end of the day… Eye strain is one of the most common disorders among screen users. Understanding its real mechanisms is the first step toward effective relief.

Woman experiencing eye strain in front of a laptop

What is eye strain?

Eye strain, clinically known as asthenopia, refers to a set of ocular and peri-ocular symptoms occurring after prolonged visual effort. It is also known as Computer Vision Syndrome (CVS) — recognized by the American Optometric Association as one of the most widespread occupational disorders.

It is not a disease, but a functional warning signal: your eyes and the muscles that control them are being pushed beyond their natural capacity on a continuous basis.

Characteristic symptoms

  • Accommodative asthenopia: difficulty maintaining focus, transient blurred vision
  • Intermittent diplopia: brief double vision after sustained visual effort
  • Frontal or orbital headaches: pain localized around the eyes or forehead
  • Photophobia: increased sensitivity to light
  • Functional dry eye: eyes that sting, burn, or redden
  • Reflex tearing: excessive tear production in response to irritation
  • Transient near-work myopia: difficulty seeing at distance after a long screen session
  • Neck and back tension: often associated with poor posture compensated by visual effort

The real causes of eye strain

1. Accommodation effort and near vision

Accommodation is the mechanism by which the eye's lens changes its curvature to focus at different distances. This process is controlled by the ciliary muscles, which remain continuously contracted during near vision.

In front of a screen, these muscles stay contracted for hours on end. Like any muscle under prolonged static effort, they fatigue — a phenomenon known as accommodative spasm. The result: blurred vision, difficulty switching between near and far distances, and a persistent feeling of ocular heaviness.

Adjusting your screen distance, posture, and lighting can significantly relieve this tension. See our complete desk ergonomics guide for screen work for practical, step-by-step recommendations.

Man working intensely on a screen in an office

2. Reduced blinking

Blinking is a vital reflex for the eye: it spreads the tear film across the cornea, removes impurities, and maintains the hydration of the ocular surface. Under normal conditions, we blink 15 to 20 times per minute.

In front of a screen, visual concentration reduces this rate to 5 to 7 blinks per minute — a drop of over 60%. The tear film evaporates faster than it is renewed, exposing the cornea to ambient air. The result: functional dry eye that worsens all other eye strain symptoms and can, over time, become chronic.

Woman rubbing her eyes late at night in front of a laptop

3. Glare and peripheral light

The human eye is designed to function in balanced lighting environments. In front of a screen, it is subjected to high contrast between the bright screen surface and the darker surrounding environment, forcing the eye to constantly adapt.

Add to this screen reflections (windows, overhead lights), uncontrolled peripheral light, and imperceptible flickering (refresh rate). These parasitic stimuli force the oculomotor muscles into constant micro-adjustments, generating additional muscular fatigue and increased light sensitivity (photophobia).

Man squinting at his laptop screen in a bright open office

4. Dry ambient air

Office environments — air conditioning in summer, heating in winter — often maintain humidity levels below 40%, well under the optimal 40–60% range for ocular comfort. This dry air accelerates tear film evaporation, independently of blinking frequency.

Combined with reduced blinking, it creates a cumulative effect that significantly worsens dry eye and irritation. Contact lens wearers are particularly vulnerable to this environmental factor.

Woman experiencing dry eyes in front of a screen with air conditioning

Important: blue light does not cause eye strain

Contrary to a very widespread misconception, blue light emitted by screens is not a cause of eye strain. Scientific studies, including those from the American Academy of Ophthalmology, are clear on this point: asthenopia symptoms are linked to the mechanisms described above (accommodation, blinking, glare, dryness) — not to the wavelength of light.

However, high-energy blue light is associated with other well-documented health concerns: disruption of the circadian rhythm and melatonin production (impact on sleep quality), long-term retinal oxidative stress, and excessive nervous system stimulation in the evening.

This is why Gunnar integrates its filtration technologies (Amber and Amber Max tints) to address these blue light-related health concerns — as a complement to its technologies specifically designed to reduce eye strain.

Learn more about blue light and its health effects ›

Gunnar technology: an answer to every cause

Gunnar Optiks has developed optical technology specifically designed to reduce eye strain for screen users, addressing point by point the real mechanisms of visual fatigue.

Gunnar focus — addressing accommodation effort

Virtually all Gunnar frames incorporate a +0.2 diopter focus. This slight positive correction allows the ciliary muscles to partially relax during near vision, reducing accommodation effort and delaying the onset of muscular spasm. Imperceptible in daily use, this patented focus technology is the most directly effective answer to screen-related eye strain.

Gunnar also offers magnifying versions from +0.50 to +3.00 for presbyopic users, as well as a few no-focus (0.00) models for those who already wear prescription blue light blocking glasses.

Wrap frame design — addressing dryness and insufficient blinking

Some Gunnar frames feature a wrap-around design that creates a slight air chamber around the eyes. This reduces airflow directly on the ocular surface, limiting tear film evaporation. Eyes stay hydrated longer, significantly reducing sensations of dryness, stinging, and redness — even in air-conditioned or heated environments.

Amber tints — addressing glare and contrast

Gunnar tints (Clear, Amber, Amber Max) are not only blue light filters: they also act on contrast and glare. The Amber tint, the brand's signature, increases on-screen image contrast and reduces peripheral light scattering, thereby decreasing constant oculomotor micro-adjustments and associated photophobia.

Clear — 35% filtration, discreet protection, ideal in bright environments
Amber — signature tint, best balance of contrast, protection and daily comfort
Amber Max — 98% filtration, maximum protection for intensive use or evening sessions

Lens coatings — reducing reflections and parasitic light

Gunnar lenses feature anti-reflective coatings specifically optimized for screens, reducing ambient light reflections on the back surface of the lens. Less parasitic light means less adaptive effort for the eye, and a sharper, more stable image on screen.

Whatever your style, there's a Gunnar frame designed to relieve your eyes — explore our eye strain glasses for women and eye fatigue glasses for men.

Discover the best eye fatigue glasses designed to protect your eyes during long screen sessions.

Glasses for screen work