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Energy Saved, Sleep Lost: The Unintended Consequences of LED Lighting

166 points by Kroeler 8y ago

nchammas 8y ago
My town recently replaced the dull, orange-ish street lights in my neighborhood with very bright, white LEDs. The street is now very well-lit, but I share the author's concerns and experience with this kind of light creating an environment that's not conducive to sleep, or to unwinding in general. When I look at the new street lights I feel like they were taken out of a hospital operating room. Another thing I noticed when the new lights first went in was that the birds started chirping at all hours of the night. I don't know if they were always doing that and I only noticed after the new street lights were installed, but it makes sense that the light would have a similar impact on animals as it does on humans. I wonder if anyone else noticed this when the lights in their neighborhood were upgraded to these harsh, white LEDs.
- wavefunction 8y ago
  Amber lights are conducive to sleep since blue wavelength light messes with circadian rhythms so they might be useful on stretches of roadway that feature long-haul driving and late-night traffic like larger thorough fares but I think they have a very deleterious effect on animals and plants. One of the things I love about the suburban neighborhood I live in is how dark it is at night (relatively speaking, not like being in a true night-time darkness in the wilderness).
- agumonkey 8y ago
  There are companies making non flat non white LED lamps these days. They try to emulate the feel and color of filament bulbs but with LED films for power savings. I don't know if they improve things though.
  - graeme 8y ago
    They don’t necessarily have the same spectrum. Not an expert, but my conclusion from the little I looked into this is that lighting is hard. And decision makers don’t seem to consider externalities.
    - zaarn 8y ago
      The Sodium Lamps normally used in Street Lighting have a very very narrow colorband (their color index is basically 0, if you look at something under sodium light, it's colorless other than the sodium yellow). LEDs can be more easily adjusted and can have a wider color band plus you can use multiple modules and change color as needed (blue light in early evening when rush traffic is on and then going into narrowband sodium yellow for the night). It's a question of power delivery and PCB complexity that limits what you can do (controlling a high powered 50W LED isn't trivial)
- dannyw 8y ago
  It literally costs pennies to fix by using a film to get amber light.
  - toomuchtodo 8y ago
    Is the circuitry to change LED colors significantly more expensive? That would future proof any light temperature issues.
    - johnvanommen 8y ago
      Yes. There's an interesting Wired article, about how teams at Philips struggled to come up with the optimum filter. IIRC, at some point they were using some type of gel to 'tint' the LED light to resemble an incandescent bulb. Of course, nearly all of this has probably flown out the window, because the bulbs are so cheap now. (The Wired article was from over a decade ago.)
      - Black-Plaid 8y ago
        That was the article about the Switch bulbs if I remember correctly. I think the company went out of business. I have a couple of them and they work and look good, but are really heavy and I can't use them in certain applications that were only ever meant to hold up really light incandescents.
    - fnordfnordfnord 8y ago
      It's not circuitry, it's the phosphors used to convert the light from blue to a mix of colors resulting in some form of white.
      - deleted 8y ago
        [deleted]
  - ams6110 8y ago
    You can't change blue light to another color with a filter. The amber light has to be in the spectrum emitted by the lights to begin with. The filter just isolates it.
- fencepost 8y ago
  One of the streets I drive on regularly is the dividing line between two towns, and it actually has the new LED bulbs on one side and the older bulbs on the other. Even without the one malfunctioning LED assembly that's strobing, the difference is pretty jarring and rather disturbing. I'd much rather have the older bulbs back, or at least something closer to them in appearance. I'm not the only one to notice the difference either - I generally have my phone mounted to my driver's-side vent and on with a map, and when I'm driving on the "old bulb" side of the street with the new bulbs shining from behind on the phone, it's much brighter - presumably its light sensor is perceiving the LEDs as being much closer to daylight.
- el_benhameen 8y ago
  I live in a neighborhood where many people leave 5-6000K security lights on all night. It boggles my mind. Any possible health effects aside, I just find non-natural light in that spectrum to be really unpleasant to look at. The temperature of the security and street lights really kills an otherwise pleasant neighborhood vibe at night.
jonex 8y ago
I think she has a good point about how too much blue light might not be very good for us. There has been interesting research in this are. It's true that traditional street lights (sodium vapor lamps[1]) are warmer, but they also provide more limited light spectrum (only one frequency of yellow) for this reason they are mainly used where the price and power efficiency outweighs the limited visibilty. So it's not strange that given the option to get better color rendering at a good price, LED technology using full spectrum light has been prefferd. However, there's nothing stopping us from using LED lights with warmer spectrum, and that argument is probably good to raise. With the higher control of the spectrum that LED gives us compared to the previous street lights we might even be able to create a good compromise using warmer but still wider spectrum lights. [1] https://en.wikipedia.org/wiki/Sodium-vapor_lamp https://en.wikipedia.org/wiki/Sodium-vapor_lamp
- graeme 8y ago
  Do any LEDs match the spectrum of those sodium vapor lamp? The ones I looked at had a higher blue profile even if the output colour matched the yellow.
  - asteli 8y ago
    In fact, yes. The illumination spectrum of sodium vapor lamps is very specific -- they emit almost all of their light around 589nm (amber) [1]. You could easily replace the light from a sodium vapor lamp with an LED lamp outfitted with LEDs manufactured to emit that particular frequency of light. The LEDs themselves are not particularly expensive either. Linked a digikey page with a potential part you could use.[2] 1:https://commons.wikimedia.org/wiki/File:Low-pressure_sodium_lamp_spectrum.svg https://commons.wikimedia.org/wiki/File:Low-pressure_sodium_... 2:https://www.digikey.com/products/en?keywords=XPEBAM-L1-0000-00601CT-ND https://www.digikey.com/products/en?keywords=XPEBAM-L1-0000-...
- floatrock 8y ago
  My house's front door faces a street lamp, and ever since the town replaced it with a white LED, it's terribly blinding to walk by in the evening. I wish my door came with flux or nightshift. That being said, I wonder how much of this is marketing the wrong product. When I see towns or cities advertising the shift, they use phrases like "more natural lighting" (yes, cool white is closer to daylight) and "brighter" (a messy concept when including colors, but I think they mean perceived brightness which again goes back to cool daylight temperature). Those sound like Good Things for a city (which I imagine is why they're buying these things), but really we're being marketed the wrong things. I don't want "more natural" daylight lighting at night, because it's night and I want to sleep. It may make drivers slightly more alert, but it comes at the cost of polluting everyone else's house (like my front door). So the people being marketed these lights hear things that sound good and sound like they make our communities safe, but really these are features we don't actually want for nighttime lighting... we need to realize we need different solutions for this problem.
news_to_me 8y ago
The youtube channel Technology Connections has a couple of interesting articles about LED (and sodium-vapor lamp) bulbs in street lighting: https://www.youtube.com/watch?v=wIC-iGDTU40 https://www.youtube.com/watch?v=wIC-iGDTU40 (Actually, most if his videos are pretty interesting to explore, especially the ones about early TV)
jaggederest 8y ago
Maybe I'm more radical, but I wonder why we need such constant, brilliant illumination anyway? I know I'm an outlier but I often don't turn lights on, or only turn on task lighting, and at night outdoors I usually use moonlight when and where I can, or a dimmable flashlight if that's not sufficient.
- dannyw 8y ago
  If you drive, the lack of street illumination makes it harder (even with your lights on, of course). And driving high beam is not a solution because that’ll blind incoming drivers
  - jaggederest 8y ago
    I am used to driving in rural areas that don't have street lamps, so I'm probably not the one to consult on that kind of thing, but I don't find that streetlamps do a tremendous amount.
    - copperx 8y ago
      That's not a problem if you have good eyesight. But some people can't see well in the dark because common eye conditions such as nearsightedness.
      - jaggederest 8y ago
        I'm severely nearsighted so I'm not sure you're hitting the mark here :D
  - ajdlinux 8y ago
    If you walk, the lack of street illumination can make it difficult or impossible to navigate the area at night.
- st26 8y ago
  Somewhere along the line more light became (in the minds of the public) linearly associated with greater wealth, security, and prosperity. It's cheap now but the perception remains.
eggie 8y ago
After realizing the effect that blue light had on my sleep I went on a crusade to eliminate it from my life after sundown. I used red LED bike lights for room illumination until I found a series of alternatives. The cheap, remote-controllable 5 meter multicolor LED strips are an amazing solution to evening lighting. It is also possible to get "warmer" LED bulbs. These are often marketed as looking like antiquated filament bulbs. But the best solution is pure red light. I also removed every single blue-LED backlit computing device from my life. I've made sure to use OLED phones since they were first available. I finally have an OLED laptop, and thankfully, as they are no longer being made! The change in laptop screen really is the most transformative thing for me, as I often need to work in the evenings. I set all the backgrounds in the OS to black, and use browser plugins to set the background of the web to black as well. I have never slept better since blue LEDs came into my life. People really need to take this issue seriously. There is evidence that blue light's disruption of circadian rhythms and suppression of melatonin production is related to cancer and other health risks. Blue should be reserved for the color of the sky, which is where our bodies evolved to recognize it directly as the input to our circadian rhythms. I am pleased by the wave of "night light" filters for phones. This is a sign that people are catching on. They use the filters and feel able to get to sleep. We need to go further. OLED everywhere and deep night mode for all.
- TheSpiceIsLife 8y ago
  Have you come across Philips ChooseScene / SceneSwitch they’re and LED bulb the switches between 2700K and 4500K when switched off and back on.
  - copperx 8y ago
    I have one next to me and it goes below 2000k (1800k I think) in the third setting. Really cool to use as a night reading light.
    - TheSpiceIsLife 8y ago
      Yeah I just saw the current model have three settings, will have to get some.
agumonkey 8y ago
Are there cities trying to have zero lights at night ? Sometimes I wonder how it feels to have no light at all. There's a calming aspect to this, my mind really feels that 'no sun = no activity'. But also a little bit of fear too, unless everybody is already home.
- johnvanommen 8y ago
  I used to commute a lot from San Diego to Portland, and the blackness of Portland was jarring. San Diego has way more lights, but it also lacks cloud cover, so the light looks different.
jlarocco 8y ago
It's strange how the switch to LED lights feels rushed and often not thought through all the way. Last winter, several intersections around my city had problems with snow accumulating and blocking the stop lights, because the new LED bulbs don't generate enough heat to melt the snow that accumulates. I guess hindsight is always 20/20, but it's surprising the people paid to make those decisions didn't think of it beforehand.
- rconti 8y ago
  The snow-melting effects of incandescents seems like something that was always there and "just worked" and, therefore, required no though. I'm not sure "the people paid to make those decisions" think it through any more than any of us can take the time to consider every possible consequence of every decision we make every day. And us tech folk already could be accused of overanalyzing many things, while still missing a ton..
  - TheSpiceIsLife 8y ago
    When you’re making purchasing decisions on a large scale one of the requirements you need to be clear on is: Does the new acquisition suit the environment it will be operating in. These requirements ought be stated in the contract of sale. If the supplier makes claims that it does, and it turns out it doesn’t then they are in breach of the contract and can be tasked with making good. Of course, sometimes we get these things wrong.
    - rconti 8y ago
      Agreed. But these decisions are being made by (and I must admit here I know nothing about the subject matter at hand, this is just speculation) almost certainly tens of thousands of municipalities across the country, independently. From small towns to big cities. From huge, organized departments that attend traffic signaling conferences, to folks who treat this component of their job as almost an afterthought. And we're only noticing the towns that screwed up, not the one that wisely chose NOT to implement LEDs for these reasons. Or the ones that made the calculated choice that, based on snowfall patters in their region, energy savings, savings on maintenance costs, vs the higher purchase price of the LEDs, that the LEDs were probably the right choice.
TheSpiceIsLife 8y ago
Does no one produce and high intensity 2700K LED light for street illumination purposes? It seems like this would be an obvious and easy solution.
- scythe 8y ago
  The whole point of the LED was that the white color provides better vision at lower luminosity. If you make it yellow, there's no advantage over sodium vapor lamps which are already very efficient.
  - ScottBurson 8y ago
    They would still have a much broader spectrum. Sodium vapor lights are very unnatural [0] — I certainly wouldn't describe them as "cozy" and "more human", as the author does. Plus, the low-pressure ones are difficult to distinguish from a yellow traffic light. [0] https://en.wikipedia.org/wiki/Sodium-vapor_lamp https://en.wikipedia.org/wiki/Sodium-vapor_lamp
    - DenisM 8y ago
      I concur - I own a couple of 2300k LED lights and the light the give off is very cozy, nothing like the streetlamp.
  - TheSpiceIsLife 8y ago
    I see, thanks.
- p1mrx 8y ago
  My HOA is currently researching LED lights for our parking structures. These are the best high-intensity not-blue (3000K) candidates we've found so far: http://www.westgatemfg.com/lighting/led-outdoor-lighting/led-wall-packs.html http://www.westgatemfg.com/lighting/led-outdoor-lighting/led... The same company also makes streetlight-style LEDs, but they're all 5000K, so that's not very promising.
- antoineMoPa 8y ago
Aloha 8y ago
I'm not sure the light profile of LED streetlights are sufficiently different enough from Mercury Vapor lighting for anyone to really notice a difference - both have significant emissions in the blue spectrum, and we used MV lighting for 40 years.
- pilsetnieks 8y ago
  Are mercury vapor lamps actually widely used now, or for the past decades? I thought the most common lighting type before LEDs were sodium lamps which are most definitely not blue.
  - Aloha 8y ago
    Mercury Vapor was widely used from the early 50's to the mid-70's/early 80's
deleted 8y ago
[deleted]
vichu 8y ago
I highly suggest installing f.lux[1] on your computer and using a similar app on your phone like Twilight[2]. They've done absolute wonders for my sleep schedule and I actually feel noticeably sleepier as the night goes on when using them. And occasionally when I do turn them off (when working late at night), I feel more awake and alert which was an unexpected plus for when I'm under crunch but an unwanted side effect when I'm trying to get a good night's rest. [1] https://justgetflux.com/ https://justgetflux.com/ [2] https://play.google.com/store/apps/details?id=com.urbandroid.lux https://play.google.com/store/apps/details?id=com.urbandroid...
- severine 8y ago
  Or the free alternatives f.lux inspired, Redshift[1] (for desktop) and Red Moon[2] (for Android): [1] http://jonls.dk/redshift/ http://jonls.dk/redshift/ [2] https://f-droid.org/en/packages/com.jmstudios.redmoon/ https://f-droid.org/en/packages/com.jmstudios.redmoon/
  - 19690401 8y ago
    Unfortunately twilight gets much redder than these, and hence is much more helpful to (my) sleep.
    - severine 8y ago
      > twilight gets much redder than these Any reference to that? I've used Twilight before, and didn't notice that when moving to Red Moon. Did you mean the default settings? You have sliders for colour temperature, intensity and dim levels: https://raw.githubusercontent.com/LibreShift/red-moon/master/app/src/main/play/en-US/listing/phoneScreenshots/1.png https://raw.githubusercontent.com/LibreShift/red-moon/master... You can create different profiles as well, plus limit brightness. I just tested a very very red filter (lower colour temp, higher intensity level).
- redisman 8y ago
  On iOS 11 just long press on the brightness control to get a flux-like feature
njarboe 8y ago
The US has banned[1] the (previously) standard low temperature (~2500k) incandescent light bulbs that have a black body radiation profile. Lots of low frequency. I really prefer these at night and could not find replacements. Eventually someone suggested that the key words are "rugged service". That and "incandescent light bulb" will get you many options on amazon, ebay, etc. Not sure if I need to stock up on these or if they will continue to be available into the future. [1] https://en.wikipedia.org/wiki/Phase-out_of_incandescent_light_bulbs#United_States https://en.wikipedia.org/wiki/Phase-out_of_incandescent_ligh...
- mchahn 8y ago
  > The US has banned[1] the (previously) standard low temperature (~2500k) incandescent light bulbs Not true. They established minimum efficiency rules. Old 60W bulbs can meet the rules but 100W cannot. You can still buy 60W incandescent bulbs everywhere. https://www.homedepot.com/b/Lighting-Light-Bulbs-Incandescent-Light-Bulbs/N-5yc1vZbmgl https://www.homedepot.com/b/Lighting-Light-Bulbs-Incandescen...
  - ams6110 8y ago
    Those 60 watt bulbs are about a dollar a bulb or more. Before the new rules, you used to be able to buy them for about a fourth of that cost.
    - mchahn 8y ago
      > you used to be able to buy them for about a fourth of that cost. The skeptic in me assumes they are taking advantage of the misconception and luring in people wanting incandescent bulbs before they run out.
      - DiabloD3 8y ago
        The skeptic in you would be pleased to know those "post-ban" bulbs fail much faster, and live about a quarter of the time. As much as I tried to avoid all of these new ugly light bulbs (never met a florescent that looked right, and it took me a long time to find an acceptable LED), I eventually just got rid of all incandescents and got CREE warm whites.
graeme 8y ago
Has anyone tried the Health-e screen covers mentioned? I’m wondering how effective they are and how easy they are to use. I currently use reduce white point and color filters at night.
DogOnTheWeb 8y ago
I would love to see a night-mode solution for televisions, either via an HDMI pass-through device or a film if necessary. Do any products exist for that use case?
- adrianmonk 8y ago
  Many TVs have a light sensor and will dim the display in a dark room. It saves energy and probably makes the brightness more appropriate to the surroundings. (It doesn't adjust the color temperature as far as I know, just the brightness.) I'd check your settings. On my Samsung, it's under System -> Eco Solution -> Eco Sensor ("Automatically optimizes TV screen brightness in response to the room lighting.")
null000 8y ago
I'm concerned by the fact that this response to blue LEDs, while founded on reasonable sounding theory theory, doesn't seem to have much high quality, real-world data AFAIK (e.g. insomnia in houses with blue LEDs vs not, comparisons between people using the glasses mentioned vs not, average bedtimes of people correlated with tv usage, any studies looking for causal links in day to day life, etc). Such studies might exist, but I don't think I've seen or heard them referenced, just mentions of how blue light decreases measured meletonin or what not in clinical settings. Mostly I just hear anecdotes from people who have fully bought into the line that this is a serious problem that requires time and money thrown at it about how awesome their life is now that they've gone out of their way to reduce blue light exposure, opening them right up to the placebo effect. I'm double concerned since the answer for this seems to be "buy more stuff" and "blindly assume blue == bad without followup research or verification". This is one of those situations where it's pretty easy for companies to swoop in and offer at-best ineffective and at-worst actively harmful products to solve a problem that might or might not exist.
- gniv 8y ago
  Especially since one of the recommended solutions is buying $79 glasses which don't seem to be much better than the ones that Home Depot sells for a fraction of the price.
  - corv 8y ago
    The cheap ones are just as good.
    - wastedhours 8y ago
      In fact, I've found the cheap ones are better - I got a pair for £20 off of Amazon and found them to work better for me than the £79 pair of Gunnars I had.
- st26 8y ago
  Given we already know it disrupts melatonin (as well as noctural wildlife), this feels like one of those cases where the burden of proof is on the proponents, before we roll out millions or billions of dollars of LED streetlights around the country. You know who really stands to benefit the most? The companies that get to sell us blue equipment, and then next sell us replacement blue-filtered equipment when we prove night time blue light is a problem. The cities that have already installed 5000K or 6500K (aka "daylight") lamps will be the natural experiments.
sunjain 8y ago
I am surprised there is not much noise over this. In my city, they recently replaced street lights with the LED ones. These were so bright and piercing, I complained to the city, and they replaced ones near my house to lower intensity one. Still the other one's not the nearest to my house are still so bright, it is very unpleasant, even though they are at a distance. No one in my neighborhood seems to be bothered by these? In my opinion these pose serious risk to health, not just ours but to birds, animals and plants. Even when driving on roads, where these lights are on, they just hit you like a sunlight.
- jonstewart 8y ago
  Washington, DC is starting to switch to LEDs for streetlights. They're whiter than the old sodium bulbs, but the District uses 3000K lights for main streets and 2700K for residential streets. The LEDs are directed towards the ground at a 45° angle--the globe diffuses the light, but they produce much less light pollution and they'll save a ton of power, time, and money.
  - smolder 8y ago
    Nice to know not every municipality is too dumb to research color temp before buying into a conversion.
smolder 8y ago
The entire problem they're talking about is high color temperature, not LEDs. No need to spread FUD with titles & writing like this - I have lit my home with pleasing warm white LEDs for years and they've paid for themselves in energy savings.
anotherevan 8y ago
I always found it ironic that the controls on my CPAP machine have bright blue back-lighting - and no obvious way to adjust it. It would light up the whole bedroom if I didn't put an old hand towel over it. OTOH, our clock-radio has a nice, warm and dim orange display.
- copperx 8y ago
  My ResMed turns all of its lights off about 5 seconds after you turn it on. I thank its designers every day.
remir 8y ago
I bought some anti blue-light glasses on Amazon and they really do make a difference. 30 minutes after I put them on, I start yawning. If I took them off the effect is jarring.
- mkbkn 8y ago
  Could you share the link please? I see many options but not sure which ones are right and which ones are knock-offs.
  - remir 8y ago
    I got this pair from Uvex: https://www.amazon.ca/gp/product/B000USRG90/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1 https://www.amazon.ca/gp/product/B000USRG90/ref=oh_aui_detai... What I like about them is they cover my entire field of view. They're not really fashionable, but I only wear them inside anyway.
perilunar 8y ago
Shout out to the International Dark Sky Association. They've been talking about the problems of LED lighting for years. http://darksky.org/?s=LED+lighting http://darksky.org/?s=LED+lighting
- smolder 8y ago
  But there's no problem with LEDs, there's a problem with high color temperatures. Please stop conflating the two.
saidajigumi 8y ago
Almost separately from the circadian-rhythm concerns from the article, a major design peeve of mine are random products that have unnecessarily blinding blue LEDs. Worst example I know of: an otherwise competently executed automatic HDMI switch with several incredibly bright blue LEDs, always on. So bright as to be able to read and see all objects in the same room. So when you might dim the lights to watch something? The switch is still blinding blue, usually right at the viewers! I mitigated this by disassembling the switch and installing some 3-stop ND (neutral density) lighting gel to dim these stupid LEDs to acceptable levels. This product at least afforded a good-looking solution -- many can't be disassembled to fix the problem. See also: Dyson rechargeable vacuum cleaners. Maybe it's time for an LED shaming tumblr...
- MrBuddyCasino 8y ago
  LEDs just got more and more efficient. Even driving them with tiny currents produces bright light nowadays. I suspect once the efficiency increases stop, manufacturers will adapt and their engineers settle on limiting resistor values that are actually appropriate.
  - jacobolus 8y ago
    Blue LEDs are basically inappropriate for any purpose where they might be on at night. Making them dimmer doesn't fix the basic problem. Use an orange or red light instead.
    - mohaine 8y ago
      As a Red/Green color blind person I LOVE blue leds. They have mostly replaced the stupid Red/Green off/on indicator that I can't tell the difference between. Now if only stop lights changed to "blue means go" we would live in a sane world. Picking two colors to mean opposite things (in life and death situations) that 5% of men can't tell the difference between is just a bit silly.
      - perilunar 8y ago
sxates 8y ago
Something I've realized recently is how over lit our homes can be. Like most homes, mine have always had a bunch of lights I didn't really choose with simple on/off switches. But I'm remodeling my house now and have been testing different led lights and smart lighting systems, and in the process have discovered how much better the lights are when they're dimmed! Setting aside the blue light issue for a moment, I wonder how much a simple reduction in lumens would be helpful. Just putting our lights on a smart dimmer solution (noon home for the curious) has made a big difference. I rarely turn the dimmers above 50% and it's plenty of light with a lot less glare and using even less electricity than having leds on standard switches. With the remodeled part of the house the lights will all be LED, but 2700k and every one of them will be on a dimmer switch.
mark-r 8y ago
My 1985 Volkswagen Golf had a blue LED for the high-beam indicator. I've always wondered how they were able to afford those long before conventional wisdom said they were cheap enough.
stephenr 8y ago
I must be missing something here. Every hardware store we go to here (Thailand) has LED lights (in all forms - flood lights, 'tubes', screw-in globes, even the flexible strip-lighting for hidden lighting) in at least two and usually three 'temperatures'. From most to least 'blue', they are "Daylight", "Cool White" and "Warm White". No price difference. So, is this whole article basically just a rant because nobody this guy knows ever buys "warm white" bulbs?
- smolder 8y ago
  Yes, most people don't even know what color temperature is, because they don't change light bulbs - someone else does it.
JaggerFoo 8y ago
Try living in Sweden, where people have been dealing with sleep and light for a very very long time. LED lighting is a pussy compared to the Sun
zaarn 8y ago
The complain is really less about Blue LEDs and more about high temperature white LEDs (5000K and upwards). Those really fuck up the circadian rythm. A warm or natural white LED is much less harmful (3500K and under and 4000K respectively) and you can mix both. Only a few days ago I found a very interesting LED module that would mix both and use the natural white for full light intensity and mix over to the warm LED when you dim it via PWM or DC going as low as 2000K. Myself, I built a LED RGBW controller and I use the Red and Blue channels to change the color temperature of the strip itself. The strips can be had for very cheap on chinese websites, individual LED modules with WS2812 pins cost less than a dozen cent. High powered LEDs of various temperature don't cost that much either. It's not a hard problem and definitely solvable.
stupidcar 8y ago
"We can’t easily call for our cities to go back to a less intense light. The switch has already been made, and cash-strapped cities need the savings." Yes we can, and we should. Where does this learned helplessness come from? Cities are always cash-strapped. "It'll cost extra," should not be some trump card to shut down discussion of doing something that is provably better for the populace. There should standards devised for the idea color temperature and brightness of street lighting, and government should be required to stick to them.
audunw 8y ago
"Because red, green and blue LEDs are required to make white LED light" Just to nitpick a bit: you only need blue LEDs to make white LED lights. Most modern white LEDs use a phosphor coating (the yellow you see in the LED chip) to get white light out of the blue LED.
jaclaz 8y ago
Maybe I am barking up a completely wrong tree, but this seems to me more than anything else a shameless ad for the "healthe" filters and "Truedark" sleephacking glasses.

166 points by Kroeler 8y ago

My town recently replaced the dull, orange-ish street lights in my neighborhood with very bright, white LEDs. The street is now very well-lit, but I share the author's concerns and experience with this kind of light creating an environment that's not conducive to sleep, or to unwinding in general. When I look at the new street lights I feel like they were taken out of a hospital operating room. Another thing I noticed when the new lights first went in was that the birds started chirping at all hours of the night. I don't know if they were always doing that and I only noticed after the new street lights were installed, but it makes sense that the light would have a similar impact on animals as it does on humans. I wonder if anyone else noticed this when the lights in their neighborhood were upgraded to these harsh, white LEDs.

wavefunction 8y ago
Amber lights are conducive to sleep since blue wavelength light messes with circadian rhythms so they might be useful on stretches of roadway that feature long-haul driving and late-night traffic like larger thorough fares but I think they have a very deleterious effect on animals and plants. One of the things I love about the suburban neighborhood I live in is how dark it is at night (relatively speaking, not like being in a true night-time darkness in the wilderness).
agumonkey 8y ago
There are companies making non flat non white LED lamps these days. They try to emulate the feel and color of filament bulbs but with LED films for power savings. I don't know if they improve things though.
- graeme 8y ago
  They don’t necessarily have the same spectrum. Not an expert, but my conclusion from the little I looked into this is that lighting is hard. And decision makers don’t seem to consider externalities.
  - zaarn 8y ago
    The Sodium Lamps normally used in Street Lighting have a very very narrow colorband (their color index is basically 0, if you look at something under sodium light, it's colorless other than the sodium yellow). LEDs can be more easily adjusted and can have a wider color band plus you can use multiple modules and change color as needed (blue light in early evening when rush traffic is on and then going into narrowband sodium yellow for the night). It's a question of power delivery and PCB complexity that limits what you can do (controlling a high powered 50W LED isn't trivial)
dannyw 8y ago
It literally costs pennies to fix by using a film to get amber light.
- toomuchtodo 8y ago
  Is the circuitry to change LED colors significantly more expensive? That would future proof any light temperature issues.
  - johnvanommen 8y ago
    Yes. There's an interesting Wired article, about how teams at Philips struggled to come up with the optimum filter. IIRC, at some point they were using some type of gel to 'tint' the LED light to resemble an incandescent bulb. Of course, nearly all of this has probably flown out the window, because the bulbs are so cheap now. (The Wired article was from over a decade ago.)
    - Black-Plaid 8y ago
      That was the article about the Switch bulbs if I remember correctly. I think the company went out of business. I have a couple of them and they work and look good, but are really heavy and I can't use them in certain applications that were only ever meant to hold up really light incandescents.
  - fnordfnordfnord 8y ago
    It's not circuitry, it's the phosphors used to convert the light from blue to a mix of colors resulting in some form of white.
    - deleted 8y ago
      [deleted]
- ams6110 8y ago
  You can't change blue light to another color with a filter. The amber light has to be in the spectrum emitted by the lights to begin with. The filter just isolates it.
fencepost 8y ago
One of the streets I drive on regularly is the dividing line between two towns, and it actually has the new LED bulbs on one side and the older bulbs on the other. Even without the one malfunctioning LED assembly that's strobing, the difference is pretty jarring and rather disturbing. I'd much rather have the older bulbs back, or at least something closer to them in appearance. I'm not the only one to notice the difference either - I generally have my phone mounted to my driver's-side vent and on with a map, and when I'm driving on the "old bulb" side of the street with the new bulbs shining from behind on the phone, it's much brighter - presumably its light sensor is perceiving the LEDs as being much closer to daylight.
el_benhameen 8y ago
I live in a neighborhood where many people leave 5-6000K security lights on all night. It boggles my mind. Any possible health effects aside, I just find non-natural light in that spectrum to be really unpleasant to look at. The temperature of the security and street lights really kills an otherwise pleasant neighborhood vibe at night.

jonex 8y ago

I think she has a good point about how too much blue light might not be very good for us. There has been interesting research in this are. It's true that traditional street lights (sodium vapor lamps[1]) are warmer, but they also provide more limited light spectrum (only one frequency of yellow) for this reason they are mainly used where the price and power efficiency outweighs the limited visibilty. So it's not strange that given the option to get better color rendering at a good price, LED technology using full spectrum light has been prefferd. However, there's nothing stopping us from using LED lights with warmer spectrum, and that argument is probably good to raise. With the higher control of the spectrum that LED gives us compared to the previous street lights we might even be able to create a good compromise using warmer but still wider spectrum lights. [1] https://en.wikipedia.org/wiki/Sodium-vapor_lamp https://en.wikipedia.org/wiki/Sodium-vapor_lamp

graeme 8y ago
Do any LEDs match the spectrum of those sodium vapor lamp? The ones I looked at had a higher blue profile even if the output colour matched the yellow.
- asteli 8y ago
  In fact, yes. The illumination spectrum of sodium vapor lamps is very specific -- they emit almost all of their light around 589nm (amber) [1]. You could easily replace the light from a sodium vapor lamp with an LED lamp outfitted with LEDs manufactured to emit that particular frequency of light. The LEDs themselves are not particularly expensive either. Linked a digikey page with a potential part you could use.[2] 1:https://commons.wikimedia.org/wiki/File:Low-pressure_sodium_lamp_spectrum.svg https://commons.wikimedia.org/wiki/File:Low-pressure_sodium_... 2:https://www.digikey.com/products/en?keywords=XPEBAM-L1-0000-00601CT-ND https://www.digikey.com/products/en?keywords=XPEBAM-L1-0000-...
floatrock 8y ago
My house's front door faces a street lamp, and ever since the town replaced it with a white LED, it's terribly blinding to walk by in the evening. I wish my door came with flux or nightshift. That being said, I wonder how much of this is marketing the wrong product. When I see towns or cities advertising the shift, they use phrases like "more natural lighting" (yes, cool white is closer to daylight) and "brighter" (a messy concept when including colors, but I think they mean perceived brightness which again goes back to cool daylight temperature). Those sound like Good Things for a city (which I imagine is why they're buying these things), but really we're being marketed the wrong things. I don't want "more natural" daylight lighting at night, because it's night and I want to sleep. It may make drivers slightly more alert, but it comes at the cost of polluting everyone else's house (like my front door). So the people being marketed these lights hear things that sound good and sound like they make our communities safe, but really these are features we don't actually want for nighttime lighting... we need to realize we need different solutions for this problem.

news_to_me 8y ago

The youtube channel Technology Connections has a couple of interesting articles about LED (and sodium-vapor lamp) bulbs in street lighting: https://www.youtube.com/watch?v=wIC-iGDTU40 https://www.youtube.com/watch?v=wIC-iGDTU40 (Actually, most if his videos are pretty interesting to explore, especially the ones about early TV)

jaggederest 8y ago

Maybe I'm more radical, but I wonder why we need such constant, brilliant illumination anyway? I know I'm an outlier but I often don't turn lights on, or only turn on task lighting, and at night outdoors I usually use moonlight when and where I can, or a dimmable flashlight if that's not sufficient.

dannyw 8y ago
If you drive, the lack of street illumination makes it harder (even with your lights on, of course). And driving high beam is not a solution because that’ll blind incoming drivers
- jaggederest 8y ago
  I am used to driving in rural areas that don't have street lamps, so I'm probably not the one to consult on that kind of thing, but I don't find that streetlamps do a tremendous amount.
  - copperx 8y ago
    That's not a problem if you have good eyesight. But some people can't see well in the dark because common eye conditions such as nearsightedness.
    - jaggederest 8y ago
      I'm severely nearsighted so I'm not sure you're hitting the mark here :D
- ajdlinux 8y ago
  If you walk, the lack of street illumination can make it difficult or impossible to navigate the area at night.
st26 8y ago
Somewhere along the line more light became (in the minds of the public) linearly associated with greater wealth, security, and prosperity. It's cheap now but the perception remains.

eggie 8y ago

After realizing the effect that blue light had on my sleep I went on a crusade to eliminate it from my life after sundown. I used red LED bike lights for room illumination until I found a series of alternatives. The cheap, remote-controllable 5 meter multicolor LED strips are an amazing solution to evening lighting. It is also possible to get "warmer" LED bulbs. These are often marketed as looking like antiquated filament bulbs. But the best solution is pure red light. I also removed every single blue-LED backlit computing device from my life. I've made sure to use OLED phones since they were first available. I finally have an OLED laptop, and thankfully, as they are no longer being made! The change in laptop screen really is the most transformative thing for me, as I often need to work in the evenings. I set all the backgrounds in the OS to black, and use browser plugins to set the background of the web to black as well. I have never slept better since blue LEDs came into my life. People really need to take this issue seriously. There is evidence that blue light's disruption of circadian rhythms and suppression of melatonin production is related to cancer and other health risks. Blue should be reserved for the color of the sky, which is where our bodies evolved to recognize it directly as the input to our circadian rhythms. I am pleased by the wave of "night light" filters for phones. This is a sign that people are catching on. They use the filters and feel able to get to sleep. We need to go further. OLED everywhere and deep night mode for all.

TheSpiceIsLife 8y ago
Have you come across Philips ChooseScene / SceneSwitch they’re and LED bulb the switches between 2700K and 4500K when switched off and back on.
- copperx 8y ago
  I have one next to me and it goes below 2000k (1800k I think) in the third setting. Really cool to use as a night reading light.
  - TheSpiceIsLife 8y ago
    Yeah I just saw the current model have three settings, will have to get some.

agumonkey 8y ago

Are there cities trying to have zero lights at night ? Sometimes I wonder how it feels to have no light at all. There's a calming aspect to this, my mind really feels that 'no sun = no activity'. But also a little bit of fear too, unless everybody is already home.

johnvanommen 8y ago
I used to commute a lot from San Diego to Portland, and the blackness of Portland was jarring. San Diego has way more lights, but it also lacks cloud cover, so the light looks different.

jlarocco 8y ago

It's strange how the switch to LED lights feels rushed and often not thought through all the way. Last winter, several intersections around my city had problems with snow accumulating and blocking the stop lights, because the new LED bulbs don't generate enough heat to melt the snow that accumulates. I guess hindsight is always 20/20, but it's surprising the people paid to make those decisions didn't think of it beforehand.

rconti 8y ago
The snow-melting effects of incandescents seems like something that was always there and "just worked" and, therefore, required no though. I'm not sure "the people paid to make those decisions" think it through any more than any of us can take the time to consider every possible consequence of every decision we make every day. And us tech folk already could be accused of overanalyzing many things, while still missing a ton..
- TheSpiceIsLife 8y ago
  When you’re making purchasing decisions on a large scale one of the requirements you need to be clear on is: Does the new acquisition suit the environment it will be operating in. These requirements ought be stated in the contract of sale. If the supplier makes claims that it does, and it turns out it doesn’t then they are in breach of the contract and can be tasked with making good. Of course, sometimes we get these things wrong.
  - rconti 8y ago
    Agreed. But these decisions are being made by (and I must admit here I know nothing about the subject matter at hand, this is just speculation) almost certainly tens of thousands of municipalities across the country, independently. From small towns to big cities. From huge, organized departments that attend traffic signaling conferences, to folks who treat this component of their job as almost an afterthought. And we're only noticing the towns that screwed up, not the one that wisely chose NOT to implement LEDs for these reasons. Or the ones that made the calculated choice that, based on snowfall patters in their region, energy savings, savings on maintenance costs, vs the higher purchase price of the LEDs, that the LEDs were probably the right choice.

TheSpiceIsLife 8y ago

Does no one produce and high intensity 2700K LED light for street illumination purposes? It seems like this would be an obvious and easy solution.

scythe 8y ago
The whole point of the LED was that the white color provides better vision at lower luminosity. If you make it yellow, there's no advantage over sodium vapor lamps which are already very efficient.
- ScottBurson 8y ago
  They would still have a much broader spectrum. Sodium vapor lights are very unnatural [0] — I certainly wouldn't describe them as "cozy" and "more human", as the author does. Plus, the low-pressure ones are difficult to distinguish from a yellow traffic light. [0] https://en.wikipedia.org/wiki/Sodium-vapor_lamp https://en.wikipedia.org/wiki/Sodium-vapor_lamp
  - DenisM 8y ago
    I concur - I own a couple of 2300k LED lights and the light the give off is very cozy, nothing like the streetlamp.
- TheSpiceIsLife 8y ago
  I see, thanks.
p1mrx 8y ago
My HOA is currently researching LED lights for our parking structures. These are the best high-intensity not-blue (3000K) candidates we've found so far: http://www.westgatemfg.com/lighting/led-outdoor-lighting/led-wall-packs.html http://www.westgatemfg.com/lighting/led-outdoor-lighting/led... The same company also makes streetlight-style LEDs, but they're all 5000K, so that's not very promising.
antoineMoPa 8y ago

Aloha 8y ago

I'm not sure the light profile of LED streetlights are sufficiently different enough from Mercury Vapor lighting for anyone to really notice a difference - both have significant emissions in the blue spectrum, and we used MV lighting for 40 years.

pilsetnieks 8y ago
Are mercury vapor lamps actually widely used now, or for the past decades? I thought the most common lighting type before LEDs were sodium lamps which are most definitely not blue.
- Aloha 8y ago
  Mercury Vapor was widely used from the early 50's to the mid-70's/early 80's

deleted 8y ago

[deleted]

vichu 8y ago

I highly suggest installing f.lux[1] on your computer and using a similar app on your phone like Twilight[2]. They've done absolute wonders for my sleep schedule and I actually feel noticeably sleepier as the night goes on when using them. And occasionally when I do turn them off (when working late at night), I feel more awake and alert which was an unexpected plus for when I'm under crunch but an unwanted side effect when I'm trying to get a good night's rest. [1] https://justgetflux.com/ https://justgetflux.com/ [2] https://play.google.com/store/apps/details?id=com.urbandroid.lux https://play.google.com/store/apps/details?id=com.urbandroid...

severine 8y ago
Or the free alternatives f.lux inspired, Redshift[1] (for desktop) and Red Moon[2] (for Android): [1] http://jonls.dk/redshift/ http://jonls.dk/redshift/ [2] https://f-droid.org/en/packages/com.jmstudios.redmoon/ https://f-droid.org/en/packages/com.jmstudios.redmoon/
- 19690401 8y ago
  Unfortunately twilight gets much redder than these, and hence is much more helpful to (my) sleep.
  - severine 8y ago
    > twilight gets much redder than these Any reference to that? I've used Twilight before, and didn't notice that when moving to Red Moon. Did you mean the default settings? You have sliders for colour temperature, intensity and dim levels: https://raw.githubusercontent.com/LibreShift/red-moon/master/app/src/main/play/en-US/listing/phoneScreenshots/1.png https://raw.githubusercontent.com/LibreShift/red-moon/master... You can create different profiles as well, plus limit brightness. I just tested a very very red filter (lower colour temp, higher intensity level).
redisman 8y ago
On iOS 11 just long press on the brightness control to get a flux-like feature

njarboe 8y ago

The US has banned[1] the (previously) standard low temperature (~2500k) incandescent light bulbs that have a black body radiation profile. Lots of low frequency. I really prefer these at night and could not find replacements. Eventually someone suggested that the key words are "rugged service". That and "incandescent light bulb" will get you many options on amazon, ebay, etc. Not sure if I need to stock up on these or if they will continue to be available into the future. [1] https://en.wikipedia.org/wiki/Phase-out_of_incandescent_light_bulbs#United_States https://en.wikipedia.org/wiki/Phase-out_of_incandescent_ligh...

mchahn 8y ago
> The US has banned[1] the (previously) standard low temperature (~2500k) incandescent light bulbs Not true. They established minimum efficiency rules. Old 60W bulbs can meet the rules but 100W cannot. You can still buy 60W incandescent bulbs everywhere. https://www.homedepot.com/b/Lighting-Light-Bulbs-Incandescent-Light-Bulbs/N-5yc1vZbmgl https://www.homedepot.com/b/Lighting-Light-Bulbs-Incandescen...
- ams6110 8y ago
  Those 60 watt bulbs are about a dollar a bulb or more. Before the new rules, you used to be able to buy them for about a fourth of that cost.
  - mchahn 8y ago
    > you used to be able to buy them for about a fourth of that cost. The skeptic in me assumes they are taking advantage of the misconception and luring in people wanting incandescent bulbs before they run out.
    - DiabloD3 8y ago
      The skeptic in you would be pleased to know those "post-ban" bulbs fail much faster, and live about a quarter of the time. As much as I tried to avoid all of these new ugly light bulbs (never met a florescent that looked right, and it took me a long time to find an acceptable LED), I eventually just got rid of all incandescents and got CREE warm whites.

graeme 8y ago

Has anyone tried the Health-e screen covers mentioned? I’m wondering how effective they are and how easy they are to use. I currently use reduce white point and color filters at night.

DogOnTheWeb 8y ago

I would love to see a night-mode solution for televisions, either via an HDMI pass-through device or a film if necessary. Do any products exist for that use case?

adrianmonk 8y ago
Many TVs have a light sensor and will dim the display in a dark room. It saves energy and probably makes the brightness more appropriate to the surroundings. (It doesn't adjust the color temperature as far as I know, just the brightness.) I'd check your settings. On my Samsung, it's under System -> Eco Solution -> Eco Sensor ("Automatically optimizes TV screen brightness in response to the room lighting.")

null000 8y ago

I'm concerned by the fact that this response to blue LEDs, while founded on reasonable sounding theory theory, doesn't seem to have much high quality, real-world data AFAIK (e.g. insomnia in houses with blue LEDs vs not, comparisons between people using the glasses mentioned vs not, average bedtimes of people correlated with tv usage, any studies looking for causal links in day to day life, etc). Such studies might exist, but I don't think I've seen or heard them referenced, just mentions of how blue light decreases measured meletonin or what not in clinical settings. Mostly I just hear anecdotes from people who have fully bought into the line that this is a serious problem that requires time and money thrown at it about how awesome their life is now that they've gone out of their way to reduce blue light exposure, opening them right up to the placebo effect. I'm double concerned since the answer for this seems to be "buy more stuff" and "blindly assume blue == bad without followup research or verification". This is one of those situations where it's pretty easy for companies to swoop in and offer at-best ineffective and at-worst actively harmful products to solve a problem that might or might not exist.

gniv 8y ago
Especially since one of the recommended solutions is buying $79 glasses which don't seem to be much better than the ones that Home Depot sells for a fraction of the price.
- corv 8y ago
  The cheap ones are just as good.
  - wastedhours 8y ago
    In fact, I've found the cheap ones are better - I got a pair for £20 off of Amazon and found them to work better for me than the £79 pair of Gunnars I had.
st26 8y ago
Given we already know it disrupts melatonin (as well as noctural wildlife), this feels like one of those cases where the burden of proof is on the proponents, before we roll out millions or billions of dollars of LED streetlights around the country. You know who really stands to benefit the most? The companies that get to sell us blue equipment, and then next sell us replacement blue-filtered equipment when we prove night time blue light is a problem. The cities that have already installed 5000K or 6500K (aka "daylight") lamps will be the natural experiments.

sunjain 8y ago

I am surprised there is not much noise over this. In my city, they recently replaced street lights with the LED ones. These were so bright and piercing, I complained to the city, and they replaced ones near my house to lower intensity one. Still the other one's not the nearest to my house are still so bright, it is very unpleasant, even though they are at a distance. No one in my neighborhood seems to be bothered by these? In my opinion these pose serious risk to health, not just ours but to birds, animals and plants. Even when driving on roads, where these lights are on, they just hit you like a sunlight.

jonstewart 8y ago
Washington, DC is starting to switch to LEDs for streetlights. They're whiter than the old sodium bulbs, but the District uses 3000K lights for main streets and 2700K for residential streets. The LEDs are directed towards the ground at a 45° angle--the globe diffuses the light, but they produce much less light pollution and they'll save a ton of power, time, and money.
- smolder 8y ago
  Nice to know not every municipality is too dumb to research color temp before buying into a conversion.

smolder 8y ago

The entire problem they're talking about is high color temperature, not LEDs. No need to spread FUD with titles & writing like this - I have lit my home with pleasing warm white LEDs for years and they've paid for themselves in energy savings.

anotherevan 8y ago

I always found it ironic that the controls on my CPAP machine have bright blue back-lighting - and no obvious way to adjust it. It would light up the whole bedroom if I didn't put an old hand towel over it. OTOH, our clock-radio has a nice, warm and dim orange display.

copperx 8y ago
My ResMed turns all of its lights off about 5 seconds after you turn it on. I thank its designers every day.

remir 8y ago

I bought some anti blue-light glasses on Amazon and they really do make a difference. 30 minutes after I put them on, I start yawning. If I took them off the effect is jarring.

mkbkn 8y ago
Could you share the link please? I see many options but not sure which ones are right and which ones are knock-offs.
- remir 8y ago
  I got this pair from Uvex: https://www.amazon.ca/gp/product/B000USRG90/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1 https://www.amazon.ca/gp/product/B000USRG90/ref=oh_aui_detai... What I like about them is they cover my entire field of view. They're not really fashionable, but I only wear them inside anyway.

perilunar 8y ago

Shout out to the International Dark Sky Association. They've been talking about the problems of LED lighting for years. http://darksky.org/?s=LED+lighting http://darksky.org/?s=LED+lighting

smolder 8y ago
But there's no problem with LEDs, there's a problem with high color temperatures. Please stop conflating the two.

saidajigumi 8y ago

Almost separately from the circadian-rhythm concerns from the article, a major design peeve of mine are random products that have unnecessarily blinding blue LEDs. Worst example I know of: an otherwise competently executed automatic HDMI switch with several incredibly bright blue LEDs, always on. So bright as to be able to read and see all objects in the same room. So when you might dim the lights to watch something? The switch is still blinding blue, usually right at the viewers! I mitigated this by disassembling the switch and installing some 3-stop ND (neutral density) lighting gel to dim these stupid LEDs to acceptable levels. This product at least afforded a good-looking solution -- many can't be disassembled to fix the problem. See also: Dyson rechargeable vacuum cleaners. Maybe it's time for an LED shaming tumblr...

MrBuddyCasino 8y ago
LEDs just got more and more efficient. Even driving them with tiny currents produces bright light nowadays. I suspect once the efficiency increases stop, manufacturers will adapt and their engineers settle on limiting resistor values that are actually appropriate.
- jacobolus 8y ago
  Blue LEDs are basically inappropriate for any purpose where they might be on at night. Making them dimmer doesn't fix the basic problem. Use an orange or red light instead.
  - mohaine 8y ago
    As a Red/Green color blind person I LOVE blue leds. They have mostly replaced the stupid Red/Green off/on indicator that I can't tell the difference between. Now if only stop lights changed to "blue means go" we would live in a sane world. Picking two colors to mean opposite things (in life and death situations) that 5% of men can't tell the difference between is just a bit silly.
    - perilunar 8y ago

sxates 8y ago

Something I've realized recently is how over lit our homes can be. Like most homes, mine have always had a bunch of lights I didn't really choose with simple on/off switches. But I'm remodeling my house now and have been testing different led lights and smart lighting systems, and in the process have discovered how much better the lights are when they're dimmed! Setting aside the blue light issue for a moment, I wonder how much a simple reduction in lumens would be helpful. Just putting our lights on a smart dimmer solution (noon home for the curious) has made a big difference. I rarely turn the dimmers above 50% and it's plenty of light with a lot less glare and using even less electricity than having leds on standard switches. With the remodeled part of the house the lights will all be LED, but 2700k and every one of them will be on a dimmer switch.

mark-r 8y ago

My 1985 Volkswagen Golf had a blue LED for the high-beam indicator. I've always wondered how they were able to afford those long before conventional wisdom said they were cheap enough.

stephenr 8y ago

I must be missing something here. Every hardware store we go to here (Thailand) has LED lights (in all forms - flood lights, 'tubes', screw-in globes, even the flexible strip-lighting for hidden lighting) in at least two and usually three 'temperatures'. From most to least 'blue', they are "Daylight", "Cool White" and "Warm White". No price difference. So, is this whole article basically just a rant because nobody this guy knows ever buys "warm white" bulbs?

smolder 8y ago
Yes, most people don't even know what color temperature is, because they don't change light bulbs - someone else does it.

JaggerFoo 8y ago

Try living in Sweden, where people have been dealing with sleep and light for a very very long time. LED lighting is a pussy compared to the Sun

zaarn 8y ago

The complain is really less about Blue LEDs and more about high temperature white LEDs (5000K and upwards). Those really fuck up the circadian rythm. A warm or natural white LED is much less harmful (3500K and under and 4000K respectively) and you can mix both. Only a few days ago I found a very interesting LED module that would mix both and use the natural white for full light intensity and mix over to the warm LED when you dim it via PWM or DC going as low as 2000K. Myself, I built a LED RGBW controller and I use the Red and Blue channels to change the color temperature of the strip itself. The strips can be had for very cheap on chinese websites, individual LED modules with WS2812 pins cost less than a dozen cent. High powered LEDs of various temperature don't cost that much either. It's not a hard problem and definitely solvable.

stupidcar 8y ago

"We can’t easily call for our cities to go back to a less intense light. The switch has already been made, and cash-strapped cities need the savings." Yes we can, and we should. Where does this learned helplessness come from? Cities are always cash-strapped. "It'll cost extra," should not be some trump card to shut down discussion of doing something that is provably better for the populace. There should standards devised for the idea color temperature and brightness of street lighting, and government should be required to stick to them.

audunw 8y ago

"Because red, green and blue LEDs are required to make white LED light" Just to nitpick a bit: you only need blue LEDs to make white LED lights. Most modern white LEDs use a phosphor coating (the yellow you see in the LED chip) to get white light out of the blue LED.

jaclaz 8y ago

Maybe I am barking up a completely wrong tree, but this seems to me more than anything else a shameless ad for the "healthe" filters and "Truedark" sleephacking glasses.