> Current versions of LED streetlamps are absolutely awful.
Also they flicker too much -- a lot more than any other lighting source. It's utterly hateful and distracting, especially when you're driving or looking at a moving object.
They also fuck up dark adaptation, which makes people materially unsafe. I want the best possible night vision when I'm out alone at night -- to better be able to detect, avoid, or defend myself against any sort of miscreant that might be hiding to ambush me.
This is especially problematic because many of installations of outside lighting are done in order to provide better security, but if they're lights that dazzle and destroy dark adaptation -- this ends up being counterproductive.
I think if they're at the same frequency then they will appear to - the LED has a much sharper on/off curve than anything else. Certainly in one of the places I work they have new LED lights in the toilets and it's quite disconcerting as the strobing effect is noticeable.
The LED lighting in the streets in my town (Bournemouth, UK) doesn't exhibit this, but certainly is very 'blue' at first, and my mother (who lives there) didn't realise the effect of the blue light in terms of sleep; she used to leave her curtains open at night and wasn't sleeping well. Closing them has helped greatly in that respect.
Good fluorescent bulbs will have electronic ballasts (the driving circuit) that supply current to the bulb with a higher frequency (in the low kilohertz) than the time response of the bulb's phosphor. Thus, any sort of flicker gets low-pass filtered and doesn't appear in the output light.
Even with a subpar magnetic ballast that drives the bulb with line frequency, the phosphor never gets close to fully extinguishing -- so there is flicker, but the instantaneous light output never gets less than, say, half the maximum instantaneous light output. Look on page 3 of http://www.usailighting.com/stuff/contentmgr/files/1/e18f88d... for some instantaneous light vs time graphs for fluorescent bulbs.
LEDs have a much higher frequency response (in the tens of megahertz, easily) -- they respond quicker and more faithfully replicate their electrical drive signal as light output. You can see on page 4 of that report how violently jagged the LED's light/time plots can get.
If the manufacturer didn't want to include filter capacitors in the LED's driver because of cost/reliability concerns, well, I hope your eyes enjoy that signal because the LED, unlike the fluorescent bulb, isn't going to smooth it out.
It's certainly possible to do so and doing so would indeed avoid any sort of flicker -- but cost-cutting (good capacitors that will last the life of the LEDs are expensive) reigns supreme alas.
Also they flicker too much -- a lot more than any other lighting source. It's utterly hateful and distracting, especially when you're driving or looking at a moving object.
They also fuck up dark adaptation, which makes people materially unsafe. I want the best possible night vision when I'm out alone at night -- to better be able to detect, avoid, or defend myself against any sort of miscreant that might be hiding to ambush me.
This is especially problematic because many of installations of outside lighting are done in order to provide better security, but if they're lights that dazzle and destroy dark adaptation -- this ends up being counterproductive.