Hello everyone it has been a long time since I posted my research but am now back.I am still looking at the BLUE LIGHT in relation to the health of human beings.

What’s blue light?

Sunlight contains blue or green light, which gets the shortest wavelength but highest energy in the visible light spectrum.

Where does it come from?

Blue light comes from sunlight, and some other man-made sources like LED lighting and flat screen TVs, display screens of computers,laptops,tablets etc.

Sun light is the main source, and the main exposure to it is when we going outdoors during daylight.

Digital devices like smart phones and computers emit an amount of blue light. Compared to sunlight, the amount emitted by digital devices is much small. But considering the time people spend on the computers, electronic notebooks, smart phones and other digital devices, this small amount becomes big amount due to the time spent on the electronic gadgets.

What Effects does it have?

Every coin has two sides. Blue light is not an exception. The positive effects as below:

  • It is very important for body’s natural circadian rhythm (regulating the wakefulness and sleep cycle). Exposure to blue light in daytime helps maintain a healthy circadian rhythm, while too much exposure in nights can cause sleepless in nights and fatigue in daytime.

  • Researches show that high-energy visible light boosts alertness, helps memory and cognitive function and elevates mood. In fact, blue light is used in light therapy to treat seasonal affected disorder (SAD). Appropriate exposure to it can do good for health.

The negative effects are:

  • Risk of aging related macular degeneration.

    The lens of the adult human eye blocks almost to 100% of the ultraviolet rays from sun. But with the aging process going on, the eye natural lens’s protection use deteriorate. According to scientific studies, blue light can pass through the cornea and lens to the retina, too much exposure to it can destroy the light-sensitive cells in the retina, and thus it may increase the risk of aging related to no vision in the center of the visual field.

  • Cause computer vision syndrome.

    The short-wavelength, high energy blue light is more easily without a specific aim.When people look at the computer display screen, smart phones, electric notebook and other digital devices, thy will emit a notable amount of blue light, and the unfocused light will diminish the contrasts and cause computer vision syndrome: digital eye strain, eye fatigue, dryness, blurred vision, etc.




In the next time round research I will look at possible solutions.

Original Post

 Hi Dorcas, 

 Great post, it's interesting that you looked at both the positive side and the negative side of blue light to compare them. Often, when people hear about blue screens nowadays they only think of the very negative things blue light can do in terms of altering sleep. There's tons of research about sleep deprivation and electronic devices. Here's a link that might help you: 


 As well, it would be interesting to see if the risks of blue light outweigh the benefits, or if there are more advantages than disadvantages. 

 Neat research! 

Hey Dorcas, 

I love how your research is very clear with the information and you were able to get your points across with a nice, sweet, short post. As Sophie mentioned, its great to see you looking into both sides of blue light because the stigma around the negativity is outweighing the positives such as its benefits to our sleep cycle. Perhaps you could look more into blue light within technology specifically. Meaning does it have to be within technology?, how many hours do you have to be on your device before the negative effects have an impact on you? Anyways as normal another great round of research on blue light and here are some links for the future. 



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