In my eye clinic, patients come to see me almost every day because of eye fatigue, and most of them have one thing in common: they use electronics for long periods of time. I remember one time, a high school student, whom we called Xiao Li, brought his mother to my office. Xiao Li complained that his eyesight had deteriorated significantly in recent months, and he often felt dry and tired when studying at night. His mother was very worried because Xiao Li was in a critical period of his studies.
In the course of talking to them, I learned that Xiao Li needs to use his computer and mobile phone to process study materials for at least six hours a day. He tried turning on the device's "eye protection mode" in hopes of relieving the eye discomfort, but the effect didn't seem to be obvious. It got me thinking, does "eye care mode" really work, or do we need more outdoor activities to combat the damage that electronics do to our eyes?
The scientific principles and effect evaluation of the eye protection mode
How Night Light mode works
Night Light mode, which usually refers to a setting on the screen of an electronic device, is designed to reduce the amount of blue light emitted by the screen. Blue light is the shorter wavelength of light in the spectrum with higher energy, and excessive exposure to blue light is thought to increase eye strain and interfere with sleep cycles. The Night Light mode reduces the output of blue light by adjusting the color temperature of the screen so that the emitted light is biased towards the yellow spectrum.
Evaluation of existing studies
Effect on reducing eye strain
Studies have shown that eye protection mode can reduce eye strain to a certain extent. For example, a study of computer users who spent long periods of time on found that users who turned on eye protection mode reported less eye discomfort after long hours of work.
Effect on improving sleep quality
Blue light has a significant effect on the body's biological clock. Excessive exposure to blue light at night may suppress the secretion of melatonin, a hormone associated with regulating sleep cycles. Studies have shown that using eye protection mode or using a blue light filter app at night can improve sleep quality, especially in the hours before using electronic devices.
Effectiveness of long-term vision protection
Although the direct benefits of reducing blue light have been recognized, there is currently no consensus on whether eye protection patterns provide long-term vision protection. Some studies suggest that reducing blue light exposure can reduce pressure on the eyes, which may help slow vision loss. However, more long-term research is needed to support this.
The association between electronics use and eye health
First, staring at a screen for long periods of time can lead to eye strain. It's not just a feeling of exhaustion, it's an actual overuse of the eye muscles. The eyes need to change focus from time to time to maintain flexibility, and looking at a screen at the same distance for long periods of time weakens this ability. That's why, after a long period of using electronics, you may experience dry, painful, or blurred eyes.
Let's look at a specific example. Once, a 30-year-old programmer came to my clinic because he was working overtime for several days in a row and was using his computer for more than 12 hours to meet his deadline. He complained that his eyes were not only red and swollen, but he also felt a sharp burning sensation. After examination, he was diagnosed with dry eyes and eye fatigue. We advised him to take regular breaks, look out for 20 seconds every 20 minutes, and set a limit of 8 hours a day. Over time, his symptoms improved significantly.
In addition, long-term exposure to a screen may also accelerate the progression of myopia. This is especially evident in children and adolescents, as their eyes are still developing and are more susceptible. Statistics show that the rate of myopia among adolescents due to prolonged use of electronic devices has increased significantly over the past decade.
Finally, the potential impact of blue light emitted by screens on eye health should not be overlooked. While blue light itself is part of the visible spectrum, excessive exposure to blue light is thought to increase the risk of eye damage and may interfere with sleep patterns.
Practical advice for daily eye care
Adopt the 20-20-20 rule:
For every 20 minutes of use of the device, give your eyes a break and look 20 feet (about 6 meters) away for 20 seconds. This helps to reduce tension and fatigue in the eye muscles.
Adjust screen brightness and contrast reasonably:
Adjust the brightness of the screen according to the light of the surrounding environment, avoid the screen being too bright or too dark, and reduce irritation to the eyes. At the same time, make sure that the screen color and contrast are comfortable and not too bright or harsh.
Using the Eye Care Tool:
Consider installing eye protection software on your computer or phone, such as an app that adjusts the color temperature of the screen, to reduce the radiation of blue light. Although scientific evidence varies on the effectiveness of eye protection patterns, a moderate reduction in blue light exposure can help reduce eye strain.
Maintain proper screen distance and position:
The best viewing distance for a computer screen is about 50-70 cm, and the top of the screen should be slightly below eye level. Devices such as mobile phones or tablets should be kept at a distance of about 30-40 cm between the eyes and the screen.
Frequent blinking and use of artificial tears:
When using electronics, we blink less, resulting in dry eyes. Blinking your eyes often can help secrete tears and keep your eyes moist. Artificial tears can be used appropriately to relieve dry eyes if needed.
Increase outdoor activities:
Get involved in the outdoors as much as possible, especially in natural light. Natural light helps regulate our biological clock, while outdoor activities can also promote farsightedness and prevent the progression of myopia.
Through these hands-on steps, we can not only enjoy the convenience brought by technology, but also effectively protect our eyesight and enjoy a healthy lifestyle.