Blue LEDs: A health hazard?

Blue LED fan in PSUCould a common component used in consumer electronics lead to eyestrain, headaches, disturbed sleep, and even increase the risk of cancer? It sounds alarmist, but in fact the first three of these claims are accepted as fact by experts in relevant fields – the last, the risk of cancer, is unproven.

So what's the deadly component? The blue LED. Yes, those bright blue sparks of light on mobile phones, PCs, toasters, TVs, monitors, air purifiers, medical equipment, electric toothbrushes, and thousands of other products.

Now, don't throw away your electric toothbrush just yet – blue LEDs won't definitely make you ill. But used in the wrong way in poorly-designed products, or used at the wrong time, they can. It may sound unbelievable, but read on.

Nakamura's dream

We see blue LEDs everywhere these days. Product designers tend to use blue LEDs instead of red, green or other colors. There's a reason for that.

Developing the blue LED was very difficult. The first usable blue LEDs were created by Japanese scientist Shuji Nakamura, who followed research leads that others had dismissed as dead ends. Nakamura essentially crafted a new technique for making LEDs, instead of simply extending the processes already used for red and green LEDs. So early blue LEDs required an untried, and very expensive, manufacturing process.

This meant that when they began to appear in products, about seven years ago, they had real kudos. “Every product designer wanted the blue LED,” recalls industrial designer Brandon Eash of Design Continuum, “suddenly there's this brand new color, and it's kind of cool and high-tech looking.”

However, as blue LED makers gained experience, prices fell. An LED arms race resulted. In a battle for consumer attention, product makers adorned their products with more and more of the intense blue highlights.

Consumers get the blues

“From about four years ago, we began to see this gratuitous use of blue LEDs,” said Eash, speaking in a telephone interview from the industrial design house's US headquarters in Boston last year. “Then some complaints from customers started surfacing, saying 'well, these blue LEDs seem very intense'”

An online search will turn up hundreds of complaints from people who are so annoyed by bright LEDs on products that they cover them up or even snip their wires.

“Doesn't matter where you put it, it's like a needle sticking in your eye,” says Steve Nelson, a US-based travel industry worker who was so irritated by a powerful blue LED on a new USB hub that he eventually slapped paint over it one evening. “The damn thing wasn't even right in front of me. So you'd have thought I could just ignore it, but no, even in my peripheral vision it was too bright.”

Are they moaning about nothing?

What's all the fuss about blue LEDs? Surely a light is just a light, no matter what the color. How can there be a difference between blue and red, green, or amber?

In fact, blue light causes greater eyestrain and fatigue than other colors. It is harder for the eye to focus and causes greater glare and dazzle effects. It can also interfere with our internal body clocks, disrupting sleep patterns. Some researchers believe that even very low levels of blue light during sleep might weaken the immune system and have serious negative implications for health.

And because of Nakamura's innovation, blue LEDs really are different from old fashioned LEDs. They are much brighter.

Serendipitous luminance

The process used to make most blue LEDs “lends itself to incorporating quantum wells into the structure”, according to Barney O'Meara, of Canadian LED manufacturer, the Fox Group. “These quantum wells, together with the incorporation of indium in the epitaxy, are features [that help make] high brightness LEDs.”

Whatever the scientific explanation, the effects are obvious. Blue LEDs are literally 20 times brighter than traditional red or green LEDs. Seeing a gap in the marketplace, the Fox Group actually went back to the older LED technology and worked out a new process to manufacture more eye-friendly low intensity blue LEDs.

Other researchers headed in the opposite direction and figured out how to bring the world super-bright red and green LEDs. Despite that, bright blue LEDs continue to cause far more complaints.

Our eyes and our brains have a variety of problems with blue light, but there's no single cause for them. These problems are simply side effects of the ways in which evolution has adapted us to fit the natural environment of our planet.

Blue appears brighter at night

Firstly, blue light appears much brighter to us at night, or indoors where ambient light is low – an effect known as the Purkinje shift. This is because the rods – the sensitive monochromatic rod light detectors which our retinas rely on more at night – are most sensitive to greenish-blue light. (Some hypothesize that animals evolved the rods in underwater and jungle environments, hence the bias to blue or green – later we developed separate full color vision on top of that system, but the sensitive rods remained).

A practical example of the Purkinje Shift: a cool blue power LED on a TV might catch your eye and even attract you to buy it in a well-lit store. But after you take it home, the same LED appears distractingly bright when you watch the TV in a darkened room.

And blue is brighter in peripheral vision

The Purkinje shift also noticeably brightens blue or green lights in our peripheral vision under medium to low light conditions, because there are comparatively more rods towards the edge of the retina – hence complaints that blue LEDs are distracting even when they're not the focus of attention.

“Glaring LEDs on displays that you need to see at night... that's poor design,” says Brandon Eash. Remarkably though, it is a mistake that manufacturers continue to make.

Blue does not help you see clearly

We tend to associate blue with coolness, accuracy and clarity. But paradoxically, our eyes cannot focus blue sharply. We actually see a distracting halo around bright blue lights.

“It's well recognized that blue light is not as sharply focused on the retina as the longer wavelengths. It tends to be focused in front of the retina, so it's a little out of focus,” explains Dr. David Sliney, a US Army expert on the physiological effects of LEDs, lasers, and other bright light sources.

The various wavelengths of light focus differently because they refract at slightly different angles as they pass through the lens of the eye – an effect known as chromatic aberration.

For similar reasons, blue scatters more widely inside the eyeball, says Dr. Sliney, who answered questions by phone last year from his office at the US Army Center for Health Promotion and Preventive Medicine in Maryland

We're half blind in blue

The modern human eye evolved to see fine detail primarily with green or red light. In fact, because we are poor at distinguishing sharp detail in blue, our eyes don't really try. The most sensitive spot on the retina, the fovea centralis, has no blue light-detecting cones. That's right: we're all color blind in the most sensitive part of our eyes.

In addition, the central area of the retina, the macula, actually filters out some blue light in an effort to sharpen our vision. Snipers and marksmen sometimes improve on nature by wearing yellow-tinted 'shooters glasses', which block the distracting blue light.

“You throw away a little bit of color information in order to have a sharper view of things,” explains Dr. Sliney.

Blue glare interferes with vision

The twin effects of fuzzy focus and blue scatter both make intense blue light from a point source, like an LED, spread out across the retina, obscuring a much wider part of our visual field.

Although our retinas simply don't handle blue very well, nobody told the rest of the eye that. If blue is the strongest color available and we want to see fine detail, then we strain our eye muscles and squint trying to pull the blue into shaper focus. Try to do this for too long and you'll probably develop a nauseating headache. This won't happen in a normally lit scene, because the other colors provide the sharp detail we naturally desire.

A dazzling pain in the eye

By the way, the physical pain some people feel from high intensity discharge (HID) car headlights and particularly intense blue LEDs seems to be a combination of these focus and scatter effects, together with a third. We have a particularly strong aversion reaction to bright blue light sources, including bluish-white light. “Pupilary reflex is down in the blue [part of the spectrum]. The strongest signal to the muscles in the iris to close down comes from the blue,” says Dr. Sliney.

Intense blue light can cause long-term photochemical damage to the retina. Now, nobody is claiming that you're likely to suffer this kind of injury from a normal blue LED (unless you stare fixedly at it from a few millimetres for an hour). However, it is theorized that this may be the evolutionary driving force behind the immediate feeling of pain we get from bright light with a very strong blue component.

Our body's instinctive reaction is to reduce blue light entering the eye by closing down the pupil. This means that blue light spoils night vision. After a brief flash of blue, you can't see other colors so well for a while.

Blue light, sleep disorders, and cancer

The chain of cause and effect which might link blue light to serious conditions like cancer is a long one, and far from proven. Blue light's effects on circadian rhythms and sleep, however, are quite firmly established. Putting blue LEDs on a radio alarm clock isn't a great idea.

sleeping with blue lightLight centered in the blue part of the spectrum is known to suppress levels of melatonin in the body. Melatonin, sometimes referred to as the 'sleep' hormone, plays a key role in regulating the sleep cycle.

In summary, when melatonin levels in your body are high, you sleep; when they are low, you wake up. Blue light appears to be a kind of natural alarm clock, which wakes animals as the sky becomes blue after sunrise. Only a fairly narrow band of frequencies centered around 'pure' blue has this strong impact on melatonin.

Even very low levels of blue light, such as are emitted by a single bright blue LED, are enough to suppress melatonin levels. It's perhaps important to understand that the blue light receptors in the retina which affect melatonin levels are independent of our visual system. In other words we don't 'see' with them.

“The air-con unit has a blue power LED. You wouldn't believe how bright it is when the lights are off in the bedroom. I could actually read a book with it,” says Richard, a 30-year-old engineer from Austin, Texas (he asked that his family name not be published).

“I don't know how much the light was stopping me sleeping, but I slowly realized I didn't like it. Maybe I was really sleeping badly [because of the blue LED]. Could be it just bothered me some other way – though I don't think the noise was different than my old air conditioner. But I did feel more tired than usually, had trouble getting awake some mornings. After a week, I slapped duct tape over it [the LED]. I recall my sleeping was back to normal right away.”

While this article focuses on the health effects of blue light during sleeping hours. Pre-bedtime use of some other light sources with a strong blue component, such as high intensity lamps and PC monitors, has also been blamed for causing sleep disturbances, again by stimulating blue light receptors that trigger melatonin production.

The reason that blue LEDs are now seen as a potential hazard to sleep is that they are finding their way into bedrooms, on air ionizers, battery chargers, PC cases and many other popular gadgets. On some poorly designed products they are far brighter than they need to be, and they stay on all the time. Unlike traditional incandescent light sources which emit a broad spectrum with relatively little blue content, blue LEDs put out an intense, single wavelength blue. 

Blue LEDs couldn't really cause cancer? Could they?

Blue light at night reduces our bodies' melatonin levels, which can disturb sleep – this is generally accepted. What is far less certain [PDF] is a link between low levels of melatonin, a weakened immune system, and cancer.

Melatonin has been shown to slow or stop tumor growth in animal and test tube studies. However, in humans, the evidence is much less clear cut. Surveys showing that night shift workers are particularly prone to colo-rectal and breast cancer appear to be the strongest circumstantial evidence [PDF]  for this theory.

According to this line of reasoning, night workers suffer suppression of melatonin because they are often exposed to blue light - from daylight and other sources - during sleeping hours, and low melatonin levels make them more prone to cancer. Of course, one could suggest many other fairly plausible reasons why shift workers might be more prone to cancer, such as bad diet, poor medical care, or stress. However, the animal experiments do seem to add weight to the hypothesis that posits a melatonin-cancer link.

Manufacturers wake up

Following complaints, product designers began to wake up to the user discomfort issues with blue LEDs several years ago. PC peripherals maker Logitech said last year that it was redesigning some products to deal with the problem – although at least one of the company's newer speaker systems still attracts complaints online.

At the lower end of the price scale there's been little change. Less design-conscious manufacturers in developing countries like China appear to be unaware that users might have a problem with all those lovely cheap blue LEDs. Products like PC cases continue to show up with intense blue spotlights on the front.

“There are a lot of products out there that aren't designed intelligently at all. It strictly comes from the manufacturing floor,” commented industrial designer, Brandon Eash in an interview last year, “I think they'll continue to place LEDs wherever they see fit, without much attention.”

Practical advice

If you're bothered by a bright LED on a product, what can you do? There are several obvious solutions: covering with tape is the most common, and shouldn't affect your warranty.

Some users protect the product case with masking tape and them paint the LED housing with a black marker pen or correction fluid. One or two layers should be enough to reduce brightness considerably. This works best for LEDs which have a transparent plastic housing around or above them. It's more difficult for tiny surface mounted LEDs.

To make the light from an LED a bit less intense, you may be able to roughen the surface of the transparent housing with fine sandpaper. Unlike incandescent lights, LEDs project almost all of their light output forward, so diffusing the light helps if the LED is right in front of your eyes.

For recessed or internal LEDs it may be necessary to remove the product's case to access the whole LED housing. If you're going to that extreme, disconnecting the LED or connecting a resistor in series with it is a possibility.

This kind of end-user enhancement will certainly void your warranty, unfortunately, and could be dangerous with high voltage products. Opening power supplies is unwise unless you genuinely know what you are doing.

The long term solution for those who don't like excessively bright LEDs, according to professional designer, Eash: “You should go with another brand. Make the designers pay for their poor design decision.”


Blue is so 2004

I want to see more purple and white LEDs on stuff

White LED's can be as bright

White LED's can be as bright as blue... Purple is nice though. They make all different kinds of colors, but blue and white are definitely the brightest.

If you're wondering why

If you're wondering why White can be as bright as blue, thats because most white LED's are blue ones coated in a yellow phosphor to make them appear white. The others are a combination of red, green, and blue.

Purple is a combination of

Purple is a combination of blue and red. So you would have both a red and a blue led working together to make that purple.

The purple LEDs really

The purple LEDs really bother me. I have especially noticed it recently with the abundance of LED Christmas lights people are using outdoors. The blue LEDs are very fuzzy and out of focus on their own. It causes me a lot of eye strain. The purple LEDs are simply a mix of a blue and a red light being emitted together... so what I see is a red light with a blue halo, the red being perfectly in focus and the blue being very blurry. I thought it was so strange when I first started noticing it a few years ago. Even the green ones are fuzzy, because they are a mix of yellow and blue. I see a yellow light with a blue halo, but it blends better than the purple ones do, so they at least appear mostly green to me. For this reason, I will never buy LEDs. I seem to notice it a whole lot more than other people I know, so for a long time I thought something was wrong with me. Now I understand it to be chromatic abberation, and a normal occurrence. Blue lit store signs are a particular bother to me, as they are very difficult to read. The letters all seem to blur together, and no amount of squinting brings them in focus.

Actually, purple is a

Actually, purple is a combination of red and blue when using pigments (paint). When combining light sources, red and blue produce magenta when using LED's. It's the difference between a color additive and color subtractive system. Purple is hard to obtain with a 3 color, RGB primary system, as is gold and silver and orange.

Another reason why

Another reason why Windows-PC users are dafter than average...

I use 2 different laptops at work (an Acer and a top-spec Asus), both of which are full of blue LEDs burning my eyes after extended use - especially when working in dimly lit conditions. On the Asus I went as far as to put some tape over the LED's, making the computer look silly but at least providing some more comfort.

At home I use my macbook. No boyish shiny lights on that one - Apple tend to get things right when thinking of the user actually using their product, instead of piling flashing lights with a silly backstory on the thing.

So no, no pink, purple, green, blue and whatnot coloured LEDs - NO LED's, please. They provide no useful information, they are a leftover from old times now worshipped in all their shades and colours by those among us who are easily impressed. Yes, it is a LED. Yes, it is blue. Yes, it flashes, and yes it shines VERY bright... Bravo...

Blue LED health impact is part of a wider problem

I've been fortunate enough to work with some of the pioneers of research into architectural and environmental lighting, although I would not class myself as an expert and I am no longer involved in this field. While you have presented the health impact of lighting in a more sensationalistic way than I would like, I think there's no longer any doubt that it is a real problem. It is only the degree which remains to be determined.

Indeed, the issue is somewhat wider than you have outlined here. With regard to the melatonin supression effect, I know that researchers working in the field are concerned about any light source which emits strongly in the blue during what I might call our natural sleeping hours. This includes white lights, particularly white LEDs. This also includes activities such as watching a TV or computer screen late at night.

There is still a lot we don't know, but I believe we will see manufacturers forced to attach warning labels to 'blue risk' products within a decade. A timed reduction in the brightness of blue emitted by LCD screens is one simple solution that could - and I believe should - be implemented easily in software.

Any light source is a health

Any light source is a health hazard, not only to the eyes but our overall general health. We can not escape it...we cannot see without it. What are we going to do? Always remember to best protect yourself use the old principal, TDS, otherwise live life and enjoy yourself.

Blue/white LED lighting

In addition white and blue LEDs start to enter several lighting applications, for examples portable head lamps. If you uses many hours that light you start to be feel dizzy.

Blue movies

Hey, my Olevia TV's blue light just got covered up with paper and scot tape. I knew I wasn't the only person to be driven crazy by this. What were they thinking!?

Design Flaws

I have a laptop that has three blue LEDs positioned right below the display, so that they're shining directly into my eyes as I use the laptop (there's another three on the top of the case reporting the same 'status' conditions, but they're only visible to me with the case closed).

I had to stick a piece of tape across the openings to mute the brightness down to where I wasn't getting washout from the LEDs and being unable to see the screen clearly. Fortunately, the indicators on the top of the lower part of the case (shift lock, numlock, etc.) go through a frosted plate with the stencils on it, so they're much less bright than the three display-panel LEDs.

I would have expected that, with the positioning and brightness of the LEDs, there would have been some way for the user to adjust their brightness, but that was something the ODM apparently didn't consider.

Blue LEDs cause cancer? Is

Blue LEDs cause cancer? Is there anything left that doesn't?

Blue LEDs cause cancer?

Life causes cancer. I mean every thing wears us down even if its good or bad. What you eat the, air your breath, the car you drive. everything in your life. You just got to accept that and enjoy the time you have

someday they will figure out

someday they will figure out that the actual cause of cancer isnt anything theyve tested yet, but something mundane like deodorant or soap.

Or maybe cancer is inherited

Or maybe cancer is inherited in lab rats?

I firmly believe human

I firmly believe human psychology has the greatest impact on health. For it may be the sole underlying cause of all diseases. I speak with an immense background in biology and have heavily invested my time/money to research human psyche and neurological cognition-with physical evidence, only to reach a fact: human mind, thought, inner pressure or whatever underlying metaphysical nature drives human in essence, may be the root cause of most major health problems. Please read aforementioned keeping criticism to yourselves, however that said, I would greatly appreciate a logical philosophical argument as well.

I have come to the same

I have come to the same conclusions, codified logically thru reading about string theory, quantum physics,etc., and it all boils down to intent on vibrational particles. Earnest Holmes broke it down to the great subjective waiting for intent and that we
are "made in God's image" because we do create, hence illness is a result of mind albiet there are always exceptions.

Swedish research causes cancer.

That's the conclusion I've come up with..

All the years of Finnish media screaming into our eyes that:

Swedish Research indicates that causes cancer!

May that be "living without water" or "water" or "healthy food" or "not-so-healthy food" etc.. The only common denominator in these studies seems to be that they are all Swedish.. :)

Re: someday they will figure out

Why don't you quit washing and using deodorant for a while, and let us know how that goes.

Actually deodorant has

Actually deodorant has already been shown to cause cancer... And many soaps contain sodiom laureth sulfate or propelene glycol... which also have been proven to cause cancer!
Sorry to bust your bubble... Go natural my friend!

Propelene glycol (aka

Propelene glycol (aka Antifreeze) can cause cancer when you EAT IT. You don't eat your deodorant do you? Just because a substance causes cancer when it is ingested does not mean that just touching it (or rubbung it on your skin) is going to cause cancer too. Better do your research next time and stop drinking the bong water.

PROPYLENE glycol is an inert

PROPYLENE glycol is an inert substance that passes through the body without any negative physiological reactions (short, or long term). it is found in cough syrup, and the like. ETHYLENE glycol is the active component in antifreeze, and yes it is highly toxic. but ingestion of ethylene glycol is so toxic (in large or repeated doses), you'd likely die before the formation of any malignancies.

They reckon sex with more

They reckon sex with more then 1 partner causes cancer.This is because the bacteria of that person causes a cell to go haywire in you.

Blue LEDs cause cancer? Maybe, but not directly

If you read the whole article, you'll see that there's pretty strong evidence that strong blue light disrupts sleeping and the body clock chemical, malatonin, and that MIGHT make cancer more likely

Blue cheese?

Blue cheese?

I've totally beaten this

I've totally beaten this entire problem by simply not leaving anything on in my room after I go to bed aside from a clockradio (lightless aside from a dim orange backlight), and a fan. I never did like ionizers etc, and my computer's both downstairs where I don't have to hear or see it, and its green power light doesn't work, anyways.


I admit I thought this story was going to be like something in the National Enquirer, with a title like that, you know, BLUE LED ALIENS ATE MY GAMEBOY!!. But now I'm in two minds about it.

Can I suggest to the writer that you put more links to the scientific research that you have included? I had to look it up on Google, what I can find checks out with what you said here, but you should show a mountain of evidence for this

Wii causes CANCER! This article PROVES IT

The Nintendo Wii has a bright blue LED SO WII WILL GIVE YOU CANCER!!!!! OMFGLOL!!! PS3 FTW!!

... stfu

Just becouse the Wii has blue lights it doenst mean it will instantly cause cancer... you are just doing this to promote sony... byetheway, it could be just me but... doesn't the PS2 has a blue light to??

actually the PS3 has 3 LED's

actually the PS3 has 3 LED's Red, green, and blue....ya know to show the blu-ray drive is on.....yeah =(

Nobody ever called you dumb,

Nobody ever called you dumb, did they?

OMGOMG!! I just noticed that

OMGOMG!! I just noticed that the sky is ACTUALLY blue!! and bright too!! boohoo!! Now excuse me while I climb onto my bed and die of cancer.

Some Advice

It always helps to read the article that you are making fun of. If you did that, you'd know that they're talking about the effects of blue light during the night, not during the day.

closing your curtains is

closing your curtains is cheaper than chemo


First of all, I notice that all the links on this page are blue... are you trying to give us cancer or headaches?

More seriously, for cancer... I'm no biologist, but just LIVING is a source of cancer. When your DNA replicates, it is prone to mutation. When you are hit by a gamma ray.

What is even more funny: walking around during the day is a source of cancer, because of UV rays... So what should you do, work during day and die of cancer, or work during night and die of cancer? Maybe we should stop breathing, as I'm pretty sure there is an impressive of cancer agents floating in the air.

Conclusion, there is only one solution: confinement in a sterilized and regulated environment with vitamin pills (to avoid impurities)... c'mon, gimme a beak. I wouldn't want to spoil it, but you're all gonna die one day...

Re: Blue

That's the spirit! Well, I suppose you're LED's or not, we're all going to die, whether of natural causes or of cancer.

I have this same problem.

I just bought really nice alarm clock with Jumbo blue leds and I couldn't get to sleep at all with it on. It lit up my whole room. Will green leds also do this.

alarm clock leds

After more than 25 years of bedside clocks, the only colour I like is red.

The best clock I had was one of the earliest. As well as having 2 inch high red leds, it had a light sensor which dimmed the thing automatically at night - so much to that tricking the thing by covering the sensor with lights on made it completely unreadable - but it was still perfectly readable in the dark.

About 3 years ago I started a policy of covering _every_ light source in my bedroom. It made a noticeable difference to quality of snoozing (I suffer from Obstructive Sleep Apnea, so sleep quality is fairly critical for me). The green LED clock radio is still in there, but it's got an eyemask over it. Most other things with displays have cardboard-and-duct-tape flip covers, everything else is just covered with a blob of blutack (duct tapes and other covers don't block enough light)

Yes I could have just started wearing an eyemask - in fact I tried that, but found it and the CPAP mask for Apnea treatment are incompatible - and that I can't stand things touching my eyelids (would wake up most morning with it ripped off at some point in the night)

I could go on about the level of light pollution we put up with at night, but I won't except to say that sensible external lighting would reduce it and energy consumption markedly.

Focus - the Blue LED lights look like they are closer

My problem is that the Blue LED lights look like they are closer than the rest of the object. I was following a police motorcycle on the highway and had to close one eye because it was making me dizzy.

DAMN oO doOm in automobile motion necessity


no joke!

If the lights on the back of a POLICE OFFICER's bike are enough to make one dizzy,

(which can lead to car accidents!!! and other things)

Then this is something that seriously would need to be taken notice of and alleviated as soon as possible!!
For our police to be has harmless (when unprovoked) and as efficient as possible.

and such

re: life is cancer

It may be true that so many things in our lives might cause cancer and that we are going to eventually die someday. The point is though, to at least be able to avoid some of it, besides avoiding the headaches etc while we are alive.


What ingredient in deodorant causes cancer?

I just installed a 50 LED

I just installed a 50 LED Lamp in my bedroom (almost bright enough to use as a primary light source), SUCKA!

LEDS are Coming, and eventually you won't be able to BUY a Incandescent light bulb anymore.

All hail our New Quantum Well Powered Light Emmiting Diode overlords, who also BTW come in Pink and several shades of Ultra-Violet as well. (not popular colors, thank goodness)

Cheap Diffusor

get yourself a hot glue gun and use a really opaque glue stick. Put a little dob over the light and viola, diffusion. No need to open a case, and you can even cover recessed lights and fully exposed lights.

Plus the hotglue peels off almost anything making it a low risk at voiding a warrantee.

Blue LED makes reading easier (for me)

Thanks for the article. It's given me something to think about. Another point of view though, is that the strong reaction of the eye to blue light, causing the pupil to contract, actually makes vision clearer for some people, like myself, because it reduces their astigmatism. (At least I think this is the explanation. It might also be to do with a smaller range of wavelengths reducing chromatic aberration...) The end effect is that with a strong blue light I can read without my glasses, and with a strong white light, I can't. I haven't been doing this for long, but I haven't noticed any headaches or eyestrain. Yet. Given the comments in the article, I will probably discontinue the practice, or at least pay more attention to side-effects such as sleep disturbances, headaches, eye-strain etc.

I'll also have another look at the "shooter's glasses" idea, although preliminary investigation didn't really show any improvements from red monochromatic light.

Why does everyone think that

Why does everyone think that everything in this world leads to cancer ? just because there are people who say this ? i don't believe them.

Once you get a cancer after

Once you get a cancer after a whole life of being a "health nut" you will believe some things that you have no idea about right now , so don't be judgemental, but open minded.

White LED = blue + ...

A white LED is a blue LED with an orange phosphor in front of it. Some of the blue light comes through the phosphor unchanged, so you get RGB vision. But this means that, unlike other white light, a white LED contains an intense peak of pure blue. Right where the melatonin receptors will pick it up.

If the blue -> melatonin -> health connection proves true, then we'd better think about white vs. white light sources. A white LED light could actually be worse for you than a white fluorescent or incandescent that appeared to be the same shade of color.

Thanks for this article; it seems to be worth thinking about.

(The blue LEDs on my laptop have had Sharpie ink over them since I got it. It's ugly, but they're too distracting otherwise - especially when they blink!)


While using my bike at

While using my bike at night, I often see other cyclists with increasingly powerful bluish white headlights and I squarely hate it. I wondered why it had this effect while I barely notice incandescent lamp headlights.
Your explanation makes a lot of sense.

So let me get this straight,

So let me get this straight, Xepol: Grab a glue stick and play the viola and the light won't bother you as much?

By Xepol (not verified) - Sun, 06/17/2007 - 16:08.

get yourself a hot glue gun and use a really opaque glue stick. Put a little dob over the light and viola, diffusion.

you are all freaks! get on

you are all freaks! get on with your life. not only will you all die but i am sure you will all be holding an LED in your cold BLUE hands. (hahahahaaha, get it?)

Well I am not surprised to

Well I am not surprised to hear about this, as the matter of fact I am getting more convinced that we are surrounded with unsuspected risks (other than blue LED) that have an important contribution to our health. I guess this is the risk I assume because it's hard to keep track of everything that it's toxic or that affects my body. So far my medical exams have shown me that I have a weak immune system and I prefer to do things by the book by taking vitamins.

I just read a new study that

I just read a new study that overlayed a global map of breast cancer rates with the amount of light emitted at night and bingo, there was a significant correlation. They suspect it is because of the decrease in melatonin. Now if I could only find the link to this article.

I'm blinded

Ugh.. the blue of this website is blinding me.. and giving me cancer from my monitor!

Interesting that Blue isn't a primary color we can focus on.. that can explain why I hate cheap LED flashlights. (blue LEDs covered with yellow phosper) :)

everything has risks don't

everything has risks don't worry too much!

Blue Fluorescent Displays area as bad as Blue LEDS

When I go to bed at night, I have to cover all lights and displays except my old red LED alarm clock. I can still see those blue lights and displays with my eyes closed!

Interestingly, I purchased a

Interestingly, I purchased a super sized bright red LED alarm clock and I noticed it with closed eyelids. Eyelids are more passive to red light but less to blue because hemoglobin absorbs a lot of the blue light. If even if the blue LED's are dim, the whole room is brightly lit according to your rod cells.

Blue LEDs" A health hazard?

The 470 nm Blue LED's do in fact suppress melatonin and affect your Circadian Rhythm, but the "other side of the story" is that they are quite popular for use in preventing "S.A.D.," or Seasonal Affect Disorders.
SAD basically is a group of symptoms registering in folks when they don't get enough light to stimulate Serotonin, which Blue light does well. This means that light boxes using blue led's are popular to relieve the symptoms of SAD; depression, lethargy, lack of focus, etc.
Any light while you're sleeping is detrimental to melatonin levels, and can disrupt your sleeping patterns. Some people go to the extreme of wearing "blue blocker" sunglass like shooters wear, in order to keep blue wavelengths from suppressing melatonin and increasing serotonin.
Melatonin supplements are popular to take at bedtime anyway, and turning the dang lights off definitely promotes getting sleepy!
Spending two minutes under 10,000 LUX light sources designed to either simulate the sun or specifically target the 470 nm or Blue portion of the color spectrum undoubtedly has an effect on Circadian rhythms, but not enough research has been done on the long term effects of "mega-dosing" with pure 470nm LED's. Of course, people anxious to make a buck with "SAD Light Boxes" promote them, while no studies have actually been done that declare a certain "dose" as safe.
Here's a few words on the subject:

LED Backlit Displays

I wonder if the new Mac LED backlit displays are harmful to the eyes? It's something you would be starring at for a large amount of time.

Does the blue or white light get diffused through the screen?


Is there a kind or color of light that will promote the production on melatonin? Or in any case, revert or nulify the effects of blue light??

A little leak will sink a

A little leak will sink a great ship. A little neglect may breed great mischief. 张家界旅游

I've had a clear plastic

I've had a clear plastic drink holder that lights up brightly with a blue LED next to my computer for about 2 weeks. Ever since I put it there, I've been having terrible eye pains and headaches. I finally realized this must be what is causing it. I'm going to see if my sleep is better with it off tonight. I can't believe I didn't realize what was causing this problem...The fact that it's worse on you when it's in your peripheral makes sense to me. The light is always to the right of my computer screen.

Do you guys realize that

Do you guys realize that more and more LAPTOPS/LCD screens are being built with White LEDs backlighting, which still emits stronger in the blue spectrum than other types of back lighting for screens?!

Yes, but LED is oh-so-good for back lighting screens because it "contains no mercury at all". Well, it contains no mercury, but it wrecks havoc on your hormone levels obviously and disrupts your sleep, etc.

So, basically, those netbooks (mini-laptops) such as the Acer Aspire One and the Asus EEE PC should be avoided because they use white LED as backlight, which, even though isn't blue LED, still emits very powerfully in the blue spectrum of things. (see WIKIPEDIA; the article "LED", under "Disadvantages", look at "Blue Hazard". Yup, the blue hazard ALSO comes from WHITE LED.

And yup - most manufacturers of screens/laptops are now replacing cold cathodes with LED light, because LED is more environmentally friendly, containing "no mercury". In the future, most laptops will be with LED back lighting! Its power friendly too! Yeaa! But, oh, wait.. It disrupts your sleep and other stuff..

Call me naive but to me it

Call me naive but to me it seems like much ado about nothing, especially as it pertains to LED backlights in LCD monitors. I, for one, am glad that monitor & laptop makers are gradually replacing mercury-laden CCFL bulbs with more energy-efficient, environmentally friendly LED backlights, which provide longer lifecycles and better color reproduction & contrast. Make no mistake, mercury is far more toxic and dangerous to human health than a little blue light (of course, the mercury would normally never be released, but let's be honest - no one really disposes of these devices properly).

But not only that, all you probably need to do is make sure that you don't use your displays at full-brightness. I use my Acer Aspire One at mid-level brightness and it works wonderfully - the higher brightness levels irritate my eyes anyhow.

If you're really concerned/paranoid, you could even adjust your computer's or monitor's color settings towards a more yellowish tint/hue (that would cut down on the amount of blue light emitted).

It does NOT help the eyes if

It does NOT help the eyes if you configure the light intensity to dim down or, or by changing colors on an LED backlit screen. Your post has these 2 flaws:

1) You say that reducing the light intensity helps - many people experience the opposite on LED laptops. By setting DOWN the light intensity, some LED screens go into a fast on/off sequence, causing a sub flickering, which people report causes headaches, eye-problems. Try googling it: "LED flicker"

2) Changing the color settings towards yellow?! I don't think even changing the color settings to red or green would help, as the light emitted from the LED stays constant - it emits the same amount of high light in the blue spectrum no matter what colors there are on the screen, because when you change the colors on your screen, you only change the LCD (Liquid Crystals) that form the image/color. (Well MAYBE if you use really dark colors like black then the black liquid crystals will absorb more of the LED light coming from behind, thus maybe less blue radiation.. But I doubt it.)

Say NO to LED people!

Consider that the

Consider that the backlight's light emission is indeed "filtered" by the LCDs in front of it (that's why each pixel has a distinct color). So a yellow-colored pixel is effectively emitting ~zero blue light.

The vast majority of independent reviews, going back to the mid-07 LED-backlit Macbook Pro (one of the first consumer computers to use LED lighting), as well as anecdotal consumer commentary and reviews posted on the web, overwhelmingly favour LEDs (versus CCFLs) in terms of comfort, brightness, color reproduction/accuracy, and contrast. And this doesn't even consider that LEDs last longer, can consume less power (not all do as of yet, but some, like the newest Lenovo and EIZO monitors, post impressive savings), and don't contain highly toxic elements like mercury.

Technology is definitely moving towards LED-based solutions versus fluorescent lighting, whose usage in commercial and residential environments has been more frequently associated with headaches/eyestrain and/or other subjective sensory/comfort reactions (versus incandescent or LED technology). Dell has recently announced that it will move all of its laptops to LED technology and hopes to move its desktop monitors as well afterwards.

A Blue Christmas

My city has just installed Christmas decorations throughout the streets... and every single tree - there are hundreds of them - is wrapped in flashing blue LEDs. It's a nightmare - or would be if anyone could get to sleep.

But despite this, I'm not concerned with long-term cancer, I'm concerned with instant migraine. Bright primary colors are recognized as a migraine trigger: what research has been done into these nasty LEDs?

blue Christmas lights in the city

Do u live in Rochester Hills, MI. HA HA... I saw them, they are so pretty!

Any threat from normal LEDS?

It mentions in the article that intense blue light can cause long term photochemical damage... but not to worry about normal LEDS unless you stare at them, but wouldn't this apply to ones say on your monitor or speakers in your periphery? If you were watching a movie the LED would be sitting on relatively the same point on your retina and would that cause any damage? I'm thinking more long term than sudden damage because I'm not talking about the blinding types, but ones still bright enough to light the room when its dark. Would love an answer because I'm getting paranoid hehe :P Love the color of them though.. would be a shame for them to be risky!!

Blue light hazard

Read it again more carefully...

    ...nobody is claiming that you're likely to suffer this kind of injury from a normal blue LED (unless you stare fixedly at it from a few millimetres for an hour)

But I wonder if anyone really knows how much damage blue light causes over long periods of time. It looks like the research on this question is still in progress.

All we know for certain is that people who live to be 100 can still have reasonable vision, but they probably have some deterioration, for many different reasons. And maybe those reasons include blue light photochemical damage.

You should compare the light you get from an LED with the light you'd get from an everyday environment like a blue sky.

this is valid. you're

this is valid. you're dealing with wavelengths and subatomic particles that are unnatural. btw, blue sky is different than blue led.

because of the retina/cone thing, flashing blue lights do confuse depth perception at night. they are quite dangerous... police should reduce the brightness and flashing for normal use since it can blind people and confuse a person's depth perception.

blue lights

im a volunteer firefighter, and i have blue led lights all over my car. they're bright yes, but i'd much rather have bright lights, than people hitting me because i'm not seen.

power indicators

yer, this blue leds are very annoying, especially it they are power indicators on monitors or screens. you can not get rid of them!

guess what? you can turn them off on some of these gadgets from the setup menu!

is it foolish or what to make a blue led power indicator even if you know it disturbs people?

this is all incorrect

this is all incorrect

very good article, i wish

very good article, i wish blue lights weren't so popular. i have to cover all the blue lights in my flat as my boyfriend collapses when he sees them. if we are out and about and a police car comes past flashing its lights he cant look at them without getting very disorientated and almost falling over. he still doesn't know why this happens, if anyone has any ideas id love to hear them. not sure if its photo sensitive epilepsy as he doesnt get seizures.


First, this article claims that blue LEDs have only been around for 7 years. Well, I had a clock radio when I was 10 years old and the display was blue LED. I am in my 40's now. I believe my father also had a Casio Calculator that was also blue LED back then.

Second, my current computer boasts 7 lovely 120mm bluelit LED fans and I think it's wonderful. I've had them for close to a year and I do not suffer from any of the symptoms described in this article.

I think this article should focus more on the fact that certain people react differently to different light and they are those who will even suffer seizures from strobe or quick flashing lights rather than posting propaganda on how blue LEDs cause illness. What a bunch of crap.

Vacuum fluorescent displays

I had a clock radio when I was 10 years old and the display was blue LED. I am in my 40's now. I believe my father also had a Casio Calculator that was also blue LED back then.

Those were blue-green VFDs, not LEDs.

Blue LEDs were not available until the 1990s. Lab prototypes of Blue LEDs based on older technology were demonstrated in the 1970s but they were too dim, unreliable and inefficient. The research projects were canceled.

I would like to suggest a website for you. It could be useful when you only have a vague idea about something, but you are still determined to give the whole world the gift of your knowledge.

LED´s are dangerous.

People, LED´s are very dangerous!

For me everythink starts in 2007. When we start changing the halogen spots by LED´s spots. In my bedroom I installed even blue leds. In other rooms we installed white led spots. Very bright models. (78leds on 1 spot) I was even so crazy of leds that I installed mood panels with leds. ( an example of a mood panel). At the summer of 2008 I saw a few circles in my eye. But it was really dificult to see them. At least 2 times I saw them. In decembre 2009 I boughted me an EEE pc. In January 2009 I got sick. It was like my immunity was broken. Headdicks every day. A cold from January until May. When I started taking Vitamine C. In april 2009 these circles where back. Until that moment I didn´t thoughted that it cloud be the resuld of the LED´s spots. A while later we installed a new version of the LED spot. Very bright. One of these LED spots shine in to my eye. Normaly my eyes would close and your eyes would immediately turn away. But it didn´t. I even open my eyes more to make the leds sharper.(I had no control over it.)It was like my pupil was froozen. The day after it the eye damages was very clear. I went direct to the doctor but he didn´t believe me. It was the resuld of my high blood pressure. It was immpossible to gett eye damages of LED´s.

I already did my EEE away. The LED spots are removed in almost every room and the mood panels are shuttdown. I still got a mobile phone with LED backlight. Does somebody know of it is dangerous to look at a screen with led backlight?

Future: More of these spots ´ll be found in homes. It is even worst. Since Septembre 2009 the EU ´ll forbid bulb higher than 75watt.. The first step to forbid the bulb, halogen spots and TL-lamps. They forcing people to use LED spots and Oleds.

The LED spots have an EU Label of safety. (CE)

I´m afraid from every led, I cover every led in the room. I life from day to day and hope that I don´t gett anymore eye damage. The result of the European Institution that didn´t make there home work. I was pro EU and today very anti.

This site was really great and hopely they ´ll invest more in research.

Alios, your comment is

Alios, your comment is extremely far fetched. Most of what your saying does not make any sense or sounds like a farce. I think the only way for me to take the chance of not seeing what you say as being suspicious is to review your punctuation, spelling, and grammar before typing.

Hail to the blue led

I smoke and get cancer, my neighbour is twice as old, smokes, and no cancer. So I gave her a blue led....die, you bastard!!!!

What's next, put AC on the led, so you only get 50% chance on cancer?

Did anyone care about cover the led, besides the one with the glue?

Do you really have to be american to change the world to your person, instead of the person adapt to the enviroment?

Personally, I have my computer in my bedroom, on, with a blue led wich tell me it's on. With a bluetoothstick in in, guess what? A blue led in it. And, a mouse, wich give a blue light from the blue led in it. And I don't care about it, when time, I will sleep. When I wake up, it's still dark, but my dear comuter lights cover some darkness so I will not fall and die from falling. Get a life, get a led :)

is this the most current

is this the most current post on this site?
is it maintained at all? looks good though

thats a shame, my favorite

thats a shame, my favorite led color is possibly harmful to my health..

What seems to be lacking in

What seems to be lacking in this discussion is a real understanding (I don't understand it!) as to how much and what kind of light emission emanates from an LED backlit screen once it has passed through the LCDs. I don't think anyone can assume anything about this. It takes a dedicated study, and I don't know of any.

Many people with LED backlit notebooks have complained of extreme eyestrain and headaches, which may or may not come from the rapid flickering of the LED which provides gradations of illumination.

I had a discussion with a scientist who studies the retina, and she didn't know the answer, but felt that concerm about this was justified until the matter is settled.

Solution for bright, annoying LEDs

A simple solution is offered by LEDdim blocks the light from both alpha-neumeric LED displays such as clock radios, dvd player displays and cable boxes while they also offer "dot" LEDdims for all of those single LED indicators telling you the power is on or off, that something is connected, has power, etc. The LEDdim solution is cheap, improves everything this article points out as a problem and as no impact on expensive electronics warrantys or function.

blue led

always i wonder why the manufacturers are using only blue leds for various indicators in laptops..most of the customers are cover this s&^%ts by masking tapes.. really these are givig eye strain.

maybe blue (or

maybe blue (or purple/violet) is more dangerous than other colors, because it has a higher frequency? it's the closest to UV (ultraviolet) in the visible spectrum, as UV is just a little higher in frequency compared to violet/purple light (which is slightly higher than blue). As you go down the spectrum, the frequency decreases, so it's less dangerous. Check out wikipedia's entry on electromagnetic spectrum and notice all the colors:

Shoot, i play guitar and my

Shoot, i play guitar and my pedalboard is covered in blue LED's!!! hahah oh well

Really? I love the blue glow

Really? I love the blue glow of the LEDs, I find it really soothing and it helps me sleep.

Blue light causes what??

Then get rid of the stars too.You idiots !

Blue or green, I don't

Blue or green, I don't care.... Red isn't so bad, the eye doesn't seem to pick up the reflected glow so much (that's why they use it in airplane cockpits, and used to use it in cars), but about 10% of males are red / green color blind, so using red is now "discrimination". Personally, I could get rid of 95% of the lights on electronics, appliances, cars, etc (as well as all of the silly beeps, buzzers, and other pointless noises) and be perfectly happy.

I see blue just fine...

I see blue just fine...

Lack of blue light is dangerous as well...

Blue light at the right time of day, usually early morning, can be quite effective at treating depression and actually seems to -improve- the quality of sleep. Seasonal affective disorder might be a result of not enough blue light. The body (apart from the eyes themselves) seems to be most sensitive to blue light. I seem to recall that the sweet spot in the spectrum is pretty close to the 470 nm emission peak of one common type of blue LED.

Perhaps the key is getting the right amount of blue light at the right time in the sleep/wake cycle, rather than declaring blue light to be "bad" or "good". Different people might have different optimal levels at different times in their life as well. Blue light appears to be not that different than many (most?) other naturally occurring influences on health.

Just something to think about, especially if you tend to be depressed and it seems worse in the fall and winter.


I hate those blue shit!! It

I hate those blue shit!! It really disorients me, gives lots of headache, and my eyes hurt...

Someone should research what those shit do to us!!

LED street signs

There is a popular move to LED bill boards along our city streets. They are popular on schools, churches, and businesses. Blue and white are popular colors and according to my city planning dept. they receive so many applications for large digital LED signs new bylaws have to be written for them. I was invited to participate in this process on behalf of my community association and read about the 'blue light hazard'. If bright blue and white LED light is distracting and unsettling, affecting some people more than others, (children?) We need to address this phenomenon and prohibit them from being shone in our faces as we walk, cycle or drive through our cities.

This person is absolutely

This person is absolutely right. We can not allow this to happen if they cause damage to us, especially the children. We have to watch out for what the masses are exposed to everyday.

I wonder...?

I hereby subject myself as a real life guinea pig.

Blue LEDs, let's see... speakers, external HDD, mouse, keyboard, and some ten sources of white and blue light on PC case, which isn't down on the floor either. Some three years now, often leaving my PC on for the night as well (although I dim the LEDs). Still waiting on any of the symptoms. In fact I like the colors, and therefore it makes me happy... and has an indirect positive effect on many things.

As good news for some of the people, SOME manufacturers are taking notice of this - not blues in particular but all LEDs. At least on several NEC display models you can adjust the "power LED" (blue in this case) brightness through a settings menu, or turn it off completely. On Mionix Naos 5000 mouse you can select the leds' color from 24 choices, select which parts are lit, or turn it off completely (stays lit after you power down the PC unless turned off).

Color Rendering Index

Color temperature is only one way to measure light quality. Color Rendering Index is just as important. A poor Color Rendering Index (CRI) is the reason CCFLs and some white LEDs don't feel "right". A CRI of 100 means that everything illuminated by the light looks its natural color.

A lower CRI means that things have an unnatural hue. For example, CCFLs shift colors towards a sickly green. Sometimes the shift in color is even more obvious in photographs.

Natural light has a CRI of 100 most of the time, and incandescents score about 98.

blue led in belkin F8z121 charger harmful to eyes.

For eight months now, I have this belkin f8z121 ipod charger. Its blue led is way too bright. I cant focus my eye on other things near the blue led. Lately, i noticed I cannot read small text anymore. Credit card application fine print is so easy for me to read before, now I cant read the fine prints without the need to wear 1.00 grade reading glasses. This blue led should be recalled from all consumer products. Is someone else using belkin f8z121 ipod charger? If you are and is now having difficulty reading, we should come together and voice the damage it cause to our eye. We need injury lawyer.

Easy fix for too-bright LEDs of all colors, most sizes

You may want to check out a product called "LED dim" (do a web search and you should find their site). It's a really simple, inexpensive product that helps you reduce the effects of LEDs as much as you need to by covering them, while still letting you see that the light is on if you need to - no rewiring required, they blend right in to most tech, and you can remove them any time you like without damaging your stuff. You can also layer them to increase the effects. They've been incredibly helpful for me in reducing light-induced migraines and improving sleep (but I can still see the numbers on my alarm clock!).

Blue is fine others bother me.

I have very bright blue LED's in my dome-lights in my car and it doesn't bother me at all. I can even read stuff with no problem. I find that it is red and yellow LEDs that really bother me and give me a headache.

LED Lighting and Sleep Deprivation Effects / Eye Effects

Okay so there seems to be a problem with blue LED lighting in particular and especially at night. When I sleep at night, I close my eyes. Doesn't that solve the problem? If your lighting is too bright at night and effects sleep, get rid of it or cover it up. Isn't it that simple? Am I missing something here? Staring directly into any light source including the sun is dangerous. Don't do it. If you have LED lighting in your home, make sure it comes with covers on things like pot lights because then it makes it impossible for someone with a bad habit to stare into a particular area of the LED on purpose(or by accident)which is like focusing light onto the eye like a magnifying glass. I'm not an expert though. I'm just using common sense. Am I wrong? Please let me know. I intend on installing white LED's throughout my newer home, just in the planning stages. It's the only light that is bright, yet the most energy efficient, doesn't give off UV radiation(like CCFLs), works perfectly at cold temperatures, isn't a fire hazard, doesn't flicker or buzz causing eye strain and unneccessary noise and isn't made of toxic metals(like mercury our new craze for CCFLs...compact fluorescents) and the list goes on. To me it still looks like LED's are a big winner unless I'm wrong and even ambient non direct white lighting from the ceiling of one's home can be dangerous? I think this article just tells me to avoid blue ones but white LEDs are still the way to go for my home lighting, not?


There is more mercury in one amalgam tooth filling than in a houseload of CFLs. It helps to get things in proportion and compare risks in a more even-handed way. Remove your amalgam fillings before criticising CFLs?!

T5 tubes though are about twice as efficient as "white" LEDs or CFLs, don't flicker, don't buzz and will last as long as a good LED; i.e., 20,000 or even 50,000 hours. Also the lifetime of some T5s is guaranteed by the producer as being up to 50,000 hours of use, whereas the best deal I can get on an LED is a one year guarantee, on a product which they claim will last 25 years in normal domestic use. This doesn't seem too good.

I seem to notice if any lamps are "off-colour" and have a trace too much of one colour. Most of the time, the most pleasing colours to me are "daylight" triphosphor fluorescent tubes (colour temperature 6000 K) in rooms used in the daytime, or halogen (3200 K) or very good triphosphor tubes (I think Osram have the edge) in rooms used at night.

I'm planning to use a mixture of T5 and CFLs in my new house, but not the excessively warm white CFLs sold in the UK, which are now a somewhat sickly yellow (2500 K). Probably a white chosen to match a hot halogen lamp (3200 K or a bit more). I'll choose lampholders and shades to ensure that LEDs can replace the CFLs as soon as the efficiency improves a bit more and after hopefully these health concerns are overcome.

Hope this helps.

shades for LED's

Lightdims are patent pending specially designed removable stickers that act like sunglasses for irritating LED’s on your electronics. Lightdims Dim unwanted LED glare or flare when ambient light in your room is turned down or off. LightDims are easy to use by simply peeling off a Dim sticker and applying it to your electronics, keeping them functional while dimming annoying LED’s to a comfortable level. Lightdims simple yet elegant design does not draw unwanted attention to itself allowing your electronics to remain as clean and professional looking as the day you bought it. Just peel and stick.

Only $5.49 for over 100

LEDs replacing incandescent

LEDs replacing incandescent light, what!? These people slapping LEDs on everything and forcing them on consumers have obviously never heard of nystagmus (involuntary back-and-forth eye movements). If you get headaches or eyestrain looking at LEDs, see them jumping around, or see them sort of jump off of their spots and follow your gaze as you look away from them, I really recommend getting checked for it.

Does anyone know if the effects of blue light would be more or less severe in someone with an underdeveloped macula? I'm hoping less... Either way, I can't focus on it worth crap, and if this article and the comments are correct, it'll only get worse. Yaaay.

Easy fix

I've been building computers for many years, and all the new cases have these police grade bright BLUE!! LEDs in them. I've been scrapping out old computers and when I scrap one out, I make sure to salvage the plain old green/red or green/amber LEDs from them along with the wires. When I get a new case or do a build for someone, I almost always just swap in the regular brightness green/amber or green/red ones. Makes the machine much more pleasant to live with, especially if it's in a bedroom or dorm room. My Lian-Li case has the green/amber LEDs from an old computer long gone, and it's much nicer to look at it and see the little green/amber LEDs as opposed to the high intensity ones it came with. (Also nice not having the blue spot on the opposite side of the room!)

But blue light makes me sleep BETTER actually

Blue LEDs are pretty. To me, White LEDs are too bright. green LEDs are too commonly used and I don't like the shade of green they put out. Yelllow isn't bright enough. Red... well its just scary to see a prick of red in the middle of the night. Too creepy. I'v taped over eery single red LED in the house. almost. But I enjo=y the pretty glow of lue LEDs. As a matter of fact, for a long time, a night light i had was a blue LED. The TV in my parent's bedroom has a bright blue LED, but its right in your face so when I slept ther when my mom wanted me to, I covered it. But Before I had my new laptop, my computer had so many blue LEDs. I only taped over one, because the blinking as sort of distracting as I stared at the wall often to fall asleeep. What people should really use is color hanging LEDs. Those are very, very pretty. I remember seeing an ad in a SkyMall magazine for this giant cube of color changing LEDs and I wanted it so badly. Those ones are the only thing i'd replace for blue LEDs. Blue ones are better than the others to me Wither wa, I can't sleep properly. It' 5 AM as I am typing this. There are no more blue LEDs in my room. But all I am saying is that this theory that blue LEDs affet sleeping patterns, doesn't cmpletely apply to me, however I do get that it is a little bit bright to be shining directly into your face. I just love that cerulean glow, as cerulean has been my favorite color for a very long time.



Blue Light

Not to discredit the potential dangers of prolonged exposure to high levels of blue light, but we have been exposed to low levels of blue light at night for all of eternity by the moon and stars. So if that little blue LED in your home is causing you to lose sleep, by all means, block it out. But it's not going to kill you.

You are right - we must follow our evolution

...that harmonized us to live within certain parameters. The blueish-violet LIGHT (not blue-red color mix) at 460nm supress hard the release of melatonin (sleep hormon) because of a mysterious special cell most sensitive at 481nm blue (wiki on "Ganglion cell (non-rod non-cone) photoreceptors"). Our body is optimized for life with certain ancient-life parameters. Tweak it and our biochemical Eden is lost at some degree... blueish color corrections on computer may be good to keep the sleep out...but cost nothing to add a brown-paper color profile sometime before sleep... I always associated Blue-violet with an awesome aroused/sharp state of mind... I´m just feeling the pieces add up.

For some the blue is a godsend

All the red-green-amber lights are largely lost upon me unless I get really close or use my peripheral vision. The blue LED's are the only color that I distinguish unambiguously, so a control panel that relies on distinguishing the other colors, is of little practical use. The same applies to maps with little boxes showing different colors for the different kinds of terrain. The irony is, that I went to this site because the blue LED Christmas lights really DO bother me, but the less intense ones used on electronics panels don't.


How far away do you have to be for them not to affect you? my dad has this stupid thing for his iphone, which is in his study, which is below and to the left of my room. its probobly about 10 metres away from my window. i did put something over it but he found it and now apparently i've broken it. he says he'll have to get another one, so hopfully it wonr have a stupid purple light in it.

does anyone know how close you have to be for a light to start effecting you?

blue led headlamp

eye damaged by looking directly at headlight (crivit,Lidl) for only 15 seconds
I am 62 years old do not know yet if it will recover