The pervasive presence of digital screens in daily life has led to a common set of symptoms known as Digital Eye Strain (DES). This condition describes the visual discomfort experienced after extended periods spent viewing computers, tablets, and smartphones. For individuals who require vision correction, deciding between wearing glasses or contact lenses can affect the severity of these symptoms. The choice involves comparing how each device interacts with the eye’s natural processes and mitigates the strain caused by sustained visual focus.
Understanding Digital Eye Strain
Digital Eye Strain arises because the eyes perform visual tasks that differ significantly from natural viewing conditions. A primary mechanism involves the reduced blink rate that occurs when concentrating on a screen, often dropping from 15 blinks per minute to 5 to 7. This reduction allows the tear film to evaporate more quickly, leading to dryness, irritation, and a gritty sensation.
The physical distance to a computer screen, typically 20 to 26 inches, places a sustained demand on the eye’s focusing system. This intermediate distance requires continuous effort from the ciliary muscle to maintain a clear image, a process called accommodation. This constant muscular effort can result in symptoms of fatigue, blurred vision, and difficulty shifting focus.
Specific Benefits of Glasses for Screen Use
Glasses offer distinct advantages for mitigating Digital Eye Strain through lens customization and physical protection. They allow for specialized lens treatments that address common sources of screen discomfort. An anti-reflective coating, for example, eliminates reflections from overhead lighting and the screen itself. This reduction in glare improves visual clarity and reduces light interference.
A primary benefit is the option for a dedicated computer prescription, often called computer glasses. These lenses are specifically calculated to provide clear focus at the intermediate distance of a computer screen (20 to 26 inches). Standard glasses are often optimized for different distances, forcing the eyes to work harder. Computer glasses reduce the continuous accommodation effort required, minimizing muscular fatigue.
The physical presence of the lenses also creates a barrier between the eye and the immediate environment. This shield can help deflect air currents from fans or vents that accelerate tear film evaporation. Spectacle lenses can also be treated with filters designed to reduce exposure to high-energy visible light wavelengths emitted by screens.
Contact Lens Challenges During Computer Work
Contact lenses present unique challenges during prolonged screen time by exacerbating ocular dryness. The lens material on the corneal surface interferes with the natural stability and distribution of the tear film. This interference makes the eye more susceptible to the effects of reduced blinking that occurs during focused computer work.
When the blink rate drops significantly, the contact lens begins to dry out, as it requires a layer of moisture to remain comfortable. The lack of fresh tear replenishment under the lens leads to increased friction against the eye surface. This results in discomfort, a foreign body sensation, and redness, often intensifying as the workday progresses.
The materials used in contact lenses affect the rate at which water evaporates from the lens surface. Lenses that retain less moisture quickly compound the dryness problem, especially in a low-humidity office environment. For those who already experience mild dry eye, wearing contacts while staring at a screen can amplify these symptoms.
General Strategies for Reducing Eye Discomfort
Regardless of whether glasses or contacts are chosen, several behavioral and environmental adjustments can reduce eye discomfort. The 20-20-20 rule encourages regular breaks from sustained focus. Every 20 minutes, shift your gaze to an object at least 20 feet away for a minimum of 20 seconds. This brief pause allows the eye’s focusing muscles to relax and reset.
Optimizing the workstation setup is a key non-prescription strategy to improve visual comfort. The computer screen should be positioned roughly an arm’s length away (about 25 inches), with the top of the screen at or slightly below eye level. This encourages a slight downward gaze, which minimizes the surface area of the eye exposed between blinks.
Environmental factors like glare and poor lighting must also be managed. Desk lighting should be positioned to avoid reflections on the screen, and screen brightness should match the surrounding light levels. Using lubricating eye drops, also known as artificial tears, can supplement the natural tear film to combat dryness and irritation during long periods of concentration.