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In Japan there is quite a fad about LCD blue light filtering and how they might help reduce eyestrain, etc. The web site of a major computer accessory manufacturer has an English-language press release on iPad blue light filter with a nice graph showing how blue wavelength gets reduced, and has this claim:

Blue light is a color that is also found within natural light. However, its wavelength is extremely close to ultra-violet rays, which are harmful to the eyes and body, and it also has a high amount of energy. Hence, it is said that blue light is able to pass the cornea and crystalline lens of the eye without being absorbed, and can end up reaching the retina, which can cause it to deteriorate. There also concerns that exposure to blue light for long periods of time can have a detrimental effect on the eyes.

Is there any scientific evidence to suggest that "exposure to blue light for long periods of time can have a detrimental effect", specifically at the levels emitted by a typical LCD panel?

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Whoa! If the dozen watts of blue light from a monitor hurts your eyes, imagine what the SKY must do! I'm staying inside next to my monitor where it is safe. – Oddthinking Jan 11 '13 at 10:53
I'm very worried by the idea that light might reach my retina and damage it. I think I should ware a blindfold so that can't happen. ;-) – matt_black Jan 11 '13 at 17:20
Related non-duplicate question about blue LEDs and macular degeneration – Adam Wuerl Jan 18 '13 at 16:44
In more Japan blue light news I present blue light eyedrops (Japanese - Google translated). – Ken Y-N Jun 10 '13 at 1:44
possible duplicate of Do LED lights of any colour actually damage your eyes? – vartec Sep 9 '13 at 15:04

3 Answers 3

There is no evidence that sitting at a computer screen has any effect on the development of age-related macular degeneration or any other retinal problems except for eye straining referring to Dr. Stephen Rose. Patients at risk for age-related macular degeneration who are frequent users of LED computer monitors need to protect their eyes from harmful blue-violet light using blue-blocking lenses.

Comments below are from a roundtable paper from a lens maker called Crizal.

It is unclear what long term effect this increased exposure to short-wavelength light will have on us; but it is certainly cause for further study and for taking some steps to reduce needlessly high exposures to short wavelength light.

In addition, the proliferation of digital screens in use today has caused an increase in our exposure to blue wavelengths. The impact of this increase is potentially concerning, though further studies are warranted.

Blue light has some degree on the circardian rhythm which plays a important role in natural sleep-wake cycles. Research here and here shows that artificial light from computer monitors suppresses the natural release of melatonin during night and reducing the blue content of light at night will reduce (but not eliminate) the effect on the circadian system. However, more research evidence is needed to prove that screens are causing health problems referring to Dr. Richard Hansler.

Melatonin is a natural hormone manufactured from tryptophan by the pineal gland in the brain which plays an important role in the sleep cycle. Melatonin production and release in the brain is related to the time of day since its levels tend to rise in the evening and fall in the morning. Light at night blocks its production.

Melatonin supplements may help some people with certain sleep disorders, including jet lag, sleep problems related to shift work, and delayed sleep phase disorder (one in which people go to bed but can’t fall asleep until hours later), and insomnia. Melatonin supplements appear to be safe when used short-term; less is known about long-term safety.

Research shows that decreases in melatonin production in human and animals are known to be caused by environmental lighting, especially short-wavelength lighting (between 470 and 525 nm). Research by NASA shows neither bright nor dim 555 nm light at night could improve performance to the same extent as blue light. Melatonin effects on sleep patterns and alertness are reported here, here and here.

Effects of light

  1. Research shows electronic devices such as tablets, smartphones, and other devices with self-luminous electronic displays emit light at short wavelengths such as blue to produce white light, close to the peak sensitivity of melatonin suppression and this leads to reduction of sleep duration and disruption of sleep.

  2. Light applied at specific times of day can be used to shift the timing of the biological circadian clock and reduce misalignment.

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This question is about eye damage, not sleep disruption. – Oddthinking Nov 9 at 4:07
@Oddthinking-Changes done ! – pericles316 Nov 9 at 7:13

Ultraviolet (UV) Radiation and Your Eyes:
The Effects of Blue Light on Ocular Health:

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Whilst this may theoretically answer the question, it would be preferable to include the essential parts of the answer here, and provide the links for reference. – Jamiec May 21 '14 at 11:55

I think this is a great thread to discuss about whether blue light causes damage to eyes and skins. I also have the same scruple about damage from blue light emitting from LED monitors of computer, tablets, smartphones, etc. because i am working at an internet company and have to sit in front of the computer nearly 12 hrs per day. So i am quite concerned about the negative effect of blue light. i am even considering exchanging my job here.

One day, i happen to know a survey which claimed to have a proof on how blue light does harm to eyes. The below picture shows the truth.

blue light harm to eyes

In addition, this is an explain from Wikipedia ( It said that HEV light whose wave length is from 400 -500 nm will bring great harm to our eyes. Just as was said, HEV light has been implicated as a cause of age-related macular degeneration.

Personally, i think long period exposure to computer, iPhone and iPad, eye strain becomes more and more serious for me. One of my workmate even has eye disease and can't help outflowing tears after a day's work.

After a lot of search, i found several tips to protect our eyes from the blue light harm. Hope i am of help.

  1. Eat for good vision, at the same time, quit smoking. Studies have shown that nutrients such as omega-3 fatty acids, lutein, zinc, and vitamins C and E may help ward off age-related vision problems such as macular degeneration and cataracts. Regularly eating these foods can help lead to good eye health:

    Green, leafy vegetables such as spinach, kale, and collards Salmon, tuna, and other oily fish Eggs, nuts, beans, and other non-meat protein sources Oranges and other citrus fruits or juices

  2. Wear sunglasses for good vision. Use safety eyewear at Home, at Work, and While Playing Sports It is said that some specially designed sunglasses like Compute Eyewear has the ability to filter blue light. Also, some Apps like Bluelight Filter is claimed to filter blue light emitting from LED screens.

    Taime Computer Eyewear what i am wearing now,you can also have a try if needed.

  3. Look away from the computer, smartphones, Tablets, kindle, iPod,etc. every 40-50 minutes. You can download an app to remind you the time to free eyes from computer. EyeFoo is an example to make timed period to relax your eyes.

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Hi, can you elaborate how that picture proves that UV light is bad for your eyes? Also do you have a source for that? Furthermore I feel that the tips at the end of your answer really aren't part of the answer. – drat May 21 '14 at 8:34
The link to Wikipedia specifically says "This has not been shown to occur in humans, only inconclusively in some rodent and primate studies." I can't find a good source for "proof", all the ones I saw say "may cause damage" or similar. – Geobits May 21 '14 at 16:56
This is not "a great thread to discuss" anything. The purpose of this site is not to have a discussion. Please read Welcome to new users – RedGrittyBrick May 21 '14 at 19:24

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