How Does The Blue Light Damage Our Eyes?
Learn, why excess blue light is not good for our eye and health. Learn new things like circadian rhythm of the body. Also, know how to protect our eyes from blue lights.
All of us know that light is something through which we see the objects around us. Without light, no human can visualize anything. Light is one of the most precious gift of your god.
Light is usually useful for us but not always. Sometimes, light becomes harmful for us and not only harm our eye but the whole body. Blue and ultraviolet ray is such light. Before going on blue light first you need to understand what light is.
What is light?
Light can easily be defined as a type of radiation that is visible. There are other radiations like lights too like radioactive radiation but they are not visible like the light. Although, light is also not visible but makes things visible. But, we feel its visibility unlike other rays such as gamma radiation, radioactive radiation, etc.
White light and seven colors
White light is formed when seven colors of light(red, orange, yellow, green, blue, indigo, violet) mix together. These all seven lights are visible radiations that have some wavelength and energy. Red color has the largest wavelength and lowest energy and violet has the lowest wavelength and highest energy.
Blue light and its source
Blue light is a light or radiation which has a wavelength of around 400 to 450 nanometres. The main source of blue light is the sun. Sun emits white light which contains blue light. We receive a massive amount of blue light from sun than any other sources. Artificial sources of blue light are LED bulbs, CFL, mobile screen, tablet screen, desktop screen, etc.
Why blue light of mobile and tablets harms the most?
The blue light coming from the sun has a very minor effect on the eye. But, mobile and desktop screens have a great effect on the eyes. This is because of its closer proximity to our eye and the prolonged use of it. We usually focused on the mobile screen too much due to which all its blue light strikes our retina and causes to damage it.
Harmful effects of blue light on the human body
1. Circadian Rhythm
Our body works in a rhythm called the circadian rhythm. This is also known as sleep-wake cycle. Our body is designed in such a way that it automatically get to know when to sleep without any clock. But, the blue light of the mobile screen affects this system or rhythm. The body knows that blue light comes only from the sun. When you use mobile at night time, blue light from it gives a signal to your body that it is not night and sun is still shining in the sky. Therefore the production of melatonin in the body is blocked. Melatonin is a hormone that makes us feel sleepy. Its blockage prevents you from sleeping for around 1 to 2 hours.
2. Slow Vision loss
Blue light has a low wavelength but has high energy. Blue light easily reaches the retina of your eye. The retina is the back part of the eye where the image is formed. It contains light-sensitive cells which help us in vision. Too much-focused exposure to blue light of electronic device’s screen can damage the light-sensitive cells of the retina gradually. This gradual damage will result in permanent vision loss at your later age.
Cataract patient should avoid blue light more
Cataract patients are needed to take extra precautions for their eyes. If you are a patient of cataract, you should avoid using blue light sources as it can deepen your cataract. Cataract is caused due to UV rays exposure. Blue light rays lie so near to the UV rays. That’s why blue light should be avoided.
Uses of Blue Light
Not always, blue light is harmful. Some low-energy blue light rays are good for the human body.
In researches, it is found that some blue light boosts our alertness and cognitive function. It also elevates our mood and relaxes us.
Blue light is useful when you planned to study the whole night. As told earlier, blue light blocks the production of melatonin hormone which is necessary for sleeping.
Blue light is also used in light therapy to treat the seasonal affective disorder. It is a type of disorder which occurs due to change in seasons.
Blue light during the daytime helps in maintaining circadian rhythm. It prevents us from sleeping during the daytime.
How to protect our eyes from blue light?
There are several ways through which you can lower the harmful effects of blue light:
Keep a healthy distance from mobile and computer screens. A small distance of some inches would be good as these screens do not emit much blue light.
Try to use a blue light filter of your mobile and desktop if your handset provides this feature. This feature removes out almost all blue light and your screen turns slightly red or less white.
If your desktop and mobile do not have this feature and you need to study and work with them for long hours, then, consider buying a sunglass or lens which are capable of reflecting and blocking the blue light.
Conclusion
Blue light is harmful as well as useful. But, prolonged and focused exposure to blue light can damage the cells of the eye. Blue light from the sun helps in the development of the Child and boosts alertness. Maintained exposure to blue light helps in maintaining circadian rhythm or sleep-wake cycle of the body.
