Answer:

Blue light is a type of visible light with short wavelengths, emitted from the sun, LED lights, and electronic devices such as phones, computers, and televisions. Blue light is divided into two groups: blue-violet light (380-450 nm) and blue-turquoise light (450-500 nm). Blue light from the sun is a natural source, while artificial blue light is emitted from digital device screens over long periods.

Compared to yellow or red light spectra, blue light has higher energy and can penetrate deeper into the eye. Continuous, long-term screen exposure can lead to excessive eye accommodation, causing eye strain, dry eyes, headaches, or sleep disturbances due to the inhibition of melatonin, a hormone that regulates the sleep-wake cycle.

Currently, there is no scientific evidence confirming that blue light from electronic devices at normal usage levels directly causes myopia in children. This refractive error is primarily linked to prolonged near vision, continuous use of electronic devices, insufficient outdoor activity, and genetic factors, rather than solely blue light.

Blue light blocking glasses feature a coating that helps filter or control some blue light entering the eyes. Blue cut lenses can block most blue light, while blue control lenses primarily filter blue-violet light. These glasses can help reduce glare and alleviate eye strain or discomfort when children are studying online or looking at screens for extended periods. Some children may also find it easier to sleep when limiting blue light exposure in the evening. These effects are mainly supportive, providing comfort when using electronic devices, and do not replace other eye protection measures.

If children continue to use phones or computers continuously for 2 hours or more, look at screens from too close a distance, or use them in low-light environments, the risk of eye strain and myopia progression still increases. Wearing glasses in these situations will not prevent myopia.

According to the American Academy of Ophthalmology (AAO), there are currently no recommendations for using special glasses to prevent eye conditions when using electronic devices.

Children wearing blue light blocking glasses help reduce glare and eye strain when looking at screens for a long time. *Illustrative photo: Hai Au*

If considering their use, parents should not let children wear blue light blocking glasses all day, especially if the child does not have refractive errors or a prescription from an eye specialist. Some poor-quality glasses can tint images, reduce clarity, or cause discomfort when worn for long periods.

To limit the risk of myopia, parents should control their child's electronic device usage time, remind them to maintain an appropriate distance from the screen, avoid using phones in the dark, and apply the 20-20-20 rule to rest their eyes.

Children also need to increase outdoor activities, get enough sleep, eat a nutritious diet, and limit electronic device use before bedtime. If signs such as squinting, sitting close to the television, frequent eye rubbing, or poor distance vision appear, parents should take their child for an eye exam for timely check-up.

Dr. Le Thanh Huyen

High-Tech Eye Unit

Tam Anh Cau Giay General Clinic