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No. The article is light on details, but: > A simple device that makes LED lights flicker at a very high frequency that is imperceptible to the human eye > s
by amluto 3y ago
No.
The article is light on details, but:
> A simple device that makes LED lights flicker at a very high frequency that is imperceptible to the human eye
> shutter, which needs to be lightweight and agile enough to blink about 150 times per second.
Subjecting an entire city to 150 Hz flicker is not even remotely acceptable. IMO this needs to comply with IEEE 1789.
- op00to 3y agoWhy not?
- amluto 3y agoBecause of the rather well documented effects on health and visual performance.
- djbusby 3y agoWhen a bright light is extra annoying to light sensitive eyes it's because the lamp is actually blinking at a high frequency.
- TeMPOraL 3y agoBecause people can see the flicker. It becomes apparent with object moving quickly across your visual field (including waving your hand left-right). It creates big issues with photography and video recording.
- gnulinux 3y agoBecause cities are made for people to live in.
- mumblemumble 3y agoEven flicker that isn't perceptible to humans is still associated with increases in all sorts of things including eyestrain, headaches, anxiety, migraines, and seizures. 150Hz is well below the human perceptual threshold but still within the range that can cause problems.
- op00to 3y agoThank you!
- mortify 3y agoFlicker at certain frequencies isn't noticeable to humans in isolation. Add in other types of flicker (lights at other refresh rates, monitors, TV's, etc) and you can see the interference between them.
- djmips 3y agoAlso - it feels like it's not 'simple'. And I doubt it will ever be implemented.
- cjensen 3y agoWhy do you think 150Hz is unacceptable? People used to watch 50Hz TV, and weren't bothered too much. And San Jose used to use 60Hz flickering streetlights (sodium? not sure) to reduce light pollution for Lick Observatory.
- mumblemumble 3y agoIEEE 1789 lays a lot of that out. In a nutshell, LEDs are harsher.
- sleepybrett 3y agobecause tvs used phosphors it isnt really on/off 50hz just a slight light dip.
- mortehu 3y agoIf you look at high speed footage of a CRT monitor, you'll see that only a few scan lines are lit at a time. https://www.youtube.com/watch?v=3BJU2drrtCM&t=150s https://www.youtube.com/watch?v=3BJU2drrtCM&t=150s
- sleepybrett 3y agobecause of the high framerate you are seeing increased apparent contrast between actively lit and fading phostphors.
- amluto 3y agoPre-LED stadium lights do indeed flicker pretty egregiously, but, when correctly installed, they would be balanced between all three phases, so at least the average illumination was roughly constant. I don’t know why TVs weren’t headache-inducing. Certainly old CRT computer screens were extremely unpleasant to look at at lower refresh rates.
- deleted 3y ago[deleted]