From the Guidelines
Excessive use of small screens can negatively impact visual acuity over time, and to protect your vision, it is essential to follow the 20-20-20 rule and maintain proper viewing habits. The impact of excess usage of small screens on visual acuity is a concern, especially in children, as their visual systems are still developing 1. Some key points to consider:
- Limit continuous screen time to 20-30 minutes followed by a 20-second break looking at something 20 feet away (the 20-20-20 rule) to reduce eye strain.
- Maintain proper viewing distance (about arm's length for phones and tablets), ensure adequate lighting, and adjust screen brightness to match your environment.
- Consider using blue light filters or specialized glasses if you spend many hours on screens daily, and have regular eye examinations to monitor your visual health.
- Proper blinking (which often decreases during screen use) and using artificial tears for dry eyes can also help maintain comfort and visual acuity. According to a recent study published in 2023, recognition visual acuity testing is preferred for assessment of visual acuity to detect amblyopia, and visual acuity testing should be performed monocularly and with best refractive correction in place 1. Additionally, vision rehabilitation can provide supportive services for children with visual impairment, including assessment of visual performance and recommendations for devices, training, and accommodations 1. It is crucial to prioritize visual health and take preventive measures to minimize the risks associated with excessive small screen use, especially in children, to ensure optimal visual acuity and overall eye health.
From the Research
Impact of Excess Usage of Small Screen on Visual Acuity
- The relationship between digital screen time and myopia has been investigated in several studies, with mixed results 2, 3.
- A systematic review of 15 studies found that seven studies reported an association between screen time and myopia, but the results were not consistent 2.
- Another systematic review of 14 studies found that smartphone overuse was not significantly associated with myopia, poor vision, or blurred vision, but longer smartphone use may increase the likelihood of ocular symptoms, especially in children 3.
- A study on the effect of different screen brightness and devices on online visual acuity test found that the impact of screen brightness and device on visual acuity results was clinically insignificant 4.
- Ocular and visual discomfort associated with smartphones, tablets, and computers have been reported, including headaches, eyestrain, dry eyes, and sore eyes, but the available literature does not conclusively link these symptoms with changes in binocular vision, blinking, or ocular surface 5.
- Excess usage of small screens has been linked to various health harms, including greater obesity/adiposity, higher depressive symptoms, and poorer quality of life, but the evidence for threshold effects is weak 6.
- Regulating use time and restricting prolonged use of smartphones may prevent ocular and visual symptoms, especially in children 3.