Before discussing the effects of computers, which have become an indispensable part of our lives, on our eyes, let’s briefly understand how vision occurs.

The process of vision requires light. Light reflected from objects passes through transparent and light-bending layers of the eye, reaching the layer at the back of the eye called the retina. It stimulates specialized light-sensitive nerve cells in the retina, initiating the process of vision. If we consider that objects in our surroundings are at different distances from our eyes, for clear vision, just like the lens of a camera, our eyes adjust by changing the refraction of light to ensure that the image continually falls on the retina. This adjustment made by our eyes when looking at nearby objects is called accommodation.

Looking at a computer is an action that, like reading a book, involves using near vision, and our eye muscles work actively. Spending long hours in front of a computer will not create a refractive error in our eyes, such as hypermetropia, myopia, or astigmatism, or exacerbate existing ones, but if we have an underlying refractive error, it can become apparent as a result of the excessive use of eye muscles by the computer. Eye muscles that contract to accommodate for a long time can cause discomfort around the eyes or, if they cannot contract effectively due to muscle fatigue, temporary double vision complaints may arise. Looking into the distance relaxes the eye muscles. When looking into the distance, the eye stops focusing, and the muscles relax. If we need to spend a long time in front of a computer, taking a 2-3 minute break to look out the window every half an hour will help relax our eye muscles and reduce eye fatigue complaints.

The most noticeable effect of spending a long time in front of a computer is actually on the quality of tears. A healthy person blinks their eyes an average of 25 times per minute. With the movement of the eyelids, tears spread over the surface of the eye. When using a computer, the number of blinks is between 5-10 times per minute. The eye surface may not be adequately moistened. Reflex tears can occur to relieve burning, stinging, redness, and dryness in the eyes. Conditions that accelerate the evaporation of tears can lead to an increase in complaints. Monitors that most commonly cause eye complaints are those with cathode ray tubes. Because they send the image with intermittent flickering, focus problems related to blurred vision, double vision, eye fatigue, and pain are more frequently observed in users of these monitors. In addition, cathode ray tube monitors send more heat to the face, causing the eyes to dry out more quickly. In hot environments, air conditioning, and low humidity conditions, tear evaporation is accelerated, making dry eye complaints more pronounced. Some individuals have structurally low oil content in their tear layer. The role of the oil layer is to slow down the evaporation of tears. Individuals with weak oil layers have low tear quality, and complaints of dry eyes can occur more quickly.

The screen characteristics of the computer used can also affect eye complaints. Monitors with cathode ray tubes are most likely to cause eye complaints. Since they send the image with intermittent flickering, focus problems related to blurred vision, double vision, eye fatigue, and pain are more frequently observed in users of these monitors. In addition, cathode ray tube monitors send more heat to the face, causing the eyes to dry out more quickly. In hot environments, air conditioning, and low humidity conditions, tear evaporation is accelerated, making dry eye complaints more pronounced. Some individuals have structurally low oil content in their tear layer. The role of the oil layer is to slow down the evaporation of tears. Individuals with weak oil layers have low tear quality, and complaints of dry eyes can occur more quickly. The common feature for all computer monitors is screen contrast and screen brightness. Changes in ambient light, changes in screen contrast, and high screen brightness cause the pupils to shrink, leading to complaints of eye pain, blurred vision, and focusing problems around the eyes.

To reduce eye complaints that may occur as a result of spending a long time in front of a computer, here are some things to pay attention to:

• Choose LCD monitors and position the screen directly in front of your eyes or slightly below eye level.
• Avoid excessively hot, air-conditioned, and dusty environments.
• Remember to blink frequently and/or use artificial tear drops for support.
• Take breaks to relax your eye muscles by occasionally looking out the window, preferably at least every half an hour.
• Adjust the screen contrast and brightness to a level that does not discomfort your eyes.
• Write with large and eye-friendly characters, and prefer working with light-colored characters on a dark background to protect your eye health.