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throwaway821909

I've noticed a couple of LED bulbs (one with warnings that it's non-dimmable) where the PWM (presumably) means that even when I'm not looking for it, I'll move my hand quickly to grab something and it looks like I'm in a 20fps computer game, fun novelty but it wears off. Fortunately there are plenty where I don't see this.

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The most jarring thing is seeing the flicker when you move your eyes. If you scan your vision past a flickering light, you'll have multiple discrete images of that light left on your retina.

Strobing can also be dangerous around rotating machinery, like a lathe, because at certain RPM the machine will appear to not be spinning.

I believe the solution is to use a buck converter with enough inductance to ensure that the current to the LED is not interrupted.

I get this effect when using a dimmed led headlamp in the rain. I can see the rain drop fall in discrete steps.

I've definitely noticed that with my bike light. You don't notice the flickering normally, but rain makes it looks like you're playing a video game at 3fps. (I think I measured the flicker and the PWM frequency was like 400Hz, which is not quite as bad as 3fps.)

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