"LED Filaments" are a more direct example of phosphor-coated blue.
Most everyone has seen these now, in "Edison Bulbs" or elsewhere.
US Streetlights Are Turning Purple
51–60 of 122 posts
Re: US Streetlights Are Turning Purple
#52Earlier quoted context omitted.
No, sodium vapor lights offer great performance in terms of contrast and visibility. Especially in bad weather conditions.
Yes but that's the point: sodium vapour offers worse peripheral vision, so it could make some situations riskier.
no way, once something is into your periferal vision while in a moving car it's too late, and fact does not matter....unless it's moving realy realy fast, and then it's still too late
so the real equation will involve all sorts of other inputs, like the coulor temp, and amount of direct vs reflected light, background light conditions, weather, and indivual perception of any given driver.
*green light is the worst, as our eyes have the greatest sensitivity to it, and out night vision adaptation is to the black and white(muted coulor)
light that is natural.
current regulations are ancient, but there is no reason that a non opiniated solution cant be figured out and implimented
Re: US Streetlights Are Turning Purple
#53> And yet some streetlights have suddenly turned a jarring shade of purple. It is hard to determine the exact cause without dissecting one of the defective lights, but scientists have a hypothesis: bright purple light suggests the phosphor layer around the lights has been “delaminated”—peeled off—exposing the blue LED light underneath, Brgoch says. What an annoying/bad article. "Here are our guesses of this when we c…
I’m not sure if someone has dissected them to see what’s wrong and published the results. Deductive reasoning points to a failure of the phosphor layer in a specific type of led.
Someone did, it's accurate to state this is published work
Re: US Streetlights Are Turning Purple
#54My LCD TV did the same thing with a few of the backlight LEDs. Makes a big purplish splotch on the screen. Replaced the backlight strips and took the lens off of one of them and was surprised how small the LED is -- tiny yellow 1.5mm squares.
Re: US Streetlights Are Turning Purple
#55Earlier quoted context omitted.
Yes but that's the point: sodium vapour offers worse peripheral vision, so it could make some situations riskier.
no way, once something is into your periferal vision while in a moving car it's too late, and fact does not matter....unless it's moving realy realy fast, and then it's still too late so the real equation will involve all sorts of other inputs, like the coulor temp, and amount of direct vs reflected light, background light conditions, weather, and indivual perception of any given driver. *green light is the worst, as…
> once something is into your periferal vision while in a moving car it's too late, and fact does not matter.
When you're looking up in your rear view mirror, your view of the road ahead is from your peripheral vision. It most definitely does matter.
Re: US Streetlights Are Turning Purple
#56“ producing light that is comparable or better in quality.” They don’t support this claim about led’s, and many groups are concerned about harsh cool light interrupting circadian rhythms. They’re also hideous.
It depends strongly on implementation. LEDs can produce white light at any color temperature and CRIs ranging from terrible to great. Quality LEDs are quite nice indeed (when they're not turning purple). Most LED streetlights replaced sodium vapor lights, though, which produce the sickliest, most horrible orange color known to humanity. Just about any LED is an improvement over those.
> Quality LEDs are quite nice indeed
This is true but irrelevant when cost reduction is the motivating factor for switching to LED lighting, because that motivation will extend to the upfront purchase cost of the lamps and they will buy whatever is cheapest.
Re: US Streetlights Are Turning Purple
#57It’s interesting how many people assume these purple lights are some kind of new design choice. But really, it’s just a side effect of the phosphor layer breaking down in the LEDs. Makes you appreciate how tricky it is to balance cost, lifespan, and quality when you’re manufacturing millions of these for cities.
Design choices must include failure modes. IMHO, utterly stupid to only consider happy path.
Re: US Streetlights Are Turning Purple
#58I've never seen a LED streetlight turn people where I live. Sounds like bad light design and the LED is perhaps getting too hot. Though that said, just go and replace them as they would have had to for sodium vapour lamps they had before? And this time replace them with something that runs them at a lower temperature, especially if the environment during a summer could be hot from external temperature.
All of the purple lights I've seen have been of the same design, and they seem to be in towns that are (at least to some degree) cash-strapped. The manufacturer better be replacing these under warranty.
There aren't any of them in my town, though I've seen one LED streetlight so far that went out. The main streets have lights with a slight yellow tint, and the side streets are neutral white, which I find much more pleasing than the purplish mercury arcs they replaced.
Re: US Streetlights Are Turning Purple
#59Earlier quoted context omitted.
FWIW I do wear sunglasses for long highway drives at night. Without them halogen headlights in my side mirrors give me a migraine after a while.
FYI you can get auto-dimming side mirrors (same mechanism as for rear-view mirrors). I presume it’s a pain to install them after-market, but it can be done and maybe worth it for you if brights bother you enough to wear sunglasses.
When I had some window tinting done on a car, they tinted the side mirrors at no extra charge with excess film.
At first, I didn’t like it, but quickly grew to quite like it. (It’s pretty much only annoying for seeing the curb while parallel parking at night.)
Re: US Streetlights Are Turning Purple
#60This is happening everywhere where I live (Vancouver)