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Comment by BurningFrog | Hacker News Reader

Since this is HN, I have to ask how it works.

Assuming you didn't install sensors in your eyelids, it's probably something processing the feed of the camera?

Yes, there was a very simple OpenCV-based blink detection program on my computer that I repurposed to control my bulbs with. When it detects a blink, it turns the bulb off for 200ms, which is long enough for me to not perceive any darkness.

Wouldn't power cycling your bulbs like that lower their longevity?

No. These things are designed to turn on and off hundreds of times per second to emulate dimming.

Or even tens of thousands of times per second, according to an Analog Devices article: "Don’t Want to Hear It? Avoid the Audio Band with PWM LED Dimming at Frequencies Above 20kHz" (https://www.analog.com/en/technical-articles/avoid-the-audio...).

The part that wears out from cycling often is the ballast of the bulb. I imagine these smart lights are in the bulb's ballast, so sending the "off" command isn't de-energizing the ballast of the lightbulbs.

If you were doing it on a smart light switch that was feeding 120V to the ballasts I do imagine it would impart some additional wear and tear to the bulbs. I'm not sure how much additional wear and tear it would be on an LED, I know the main thing that wears out on a florescent is the starting circuit which needs to bring the energy of the bulb enough to start the arc which wears out over time.

It's very odd to me that bulbs don't come in two parts: Ballast and LED. That way, we wouldn't have to keep buying and throwing away the perfectly good part when the other one broke.

Ballasts are only needed on fluorescent lamps (because they have negative resistance, so if you run one by itself without a current limiter, it'll consume more and more current until it explodes)

Ah, then I meant the AC/DC converter that supplies 12V to the LEDs.

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