this post was submitted on 03 Aug 2023
1190 points (98.7% liked)
Technology
59588 readers
3077 users here now
This is a most excellent place for technology news and articles.
Our Rules
- Follow the lemmy.world rules.
- Only tech related content.
- Be excellent to each another!
- Mod approved content bots can post up to 10 articles per day.
- Threads asking for personal tech support may be deleted.
- Politics threads may be removed.
- No memes allowed as posts, OK to post as comments.
- Only approved bots from the list below, to ask if your bot can be added please contact us.
- Check for duplicates before posting, duplicates may be removed
Approved Bots
founded 1 year ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
Is there a brand that's better for LED? I get migraines and the stroking effect of LED bulbs can be a trigger.
LED christmas bulbs particularly bad. It felt like walking into a rave at the Christmas store.
Regular brand LED bulbs don't strobe at all, only the very cheap ones from AliExpress and the resellers of Chinese crapware (like Walmart) do. IKEA has some nice and cheap bulbs, for example.
Yeah, many of those christmas lights use pulse width modulation to control brightness and it is very noticeable. I hope that gets changed over for an analog voltage dimmer soon.
Also, cheap ones run directly on AC, so they flicker at 60 Hz (50 in Europe) because the current is only flowing for half the cycle.
How do high-end home LEDs get around this? Do they have a battery that caches the current between cycles?
When my wife and I bought our place, we renovated and made all lights LED. The overheads in the living room and kitchen are quite bright and steady, so they must avoid this somehow.
A bridge rectifier flips the negative current to positive, so instead of a sine wave you get a series of humps. Then a capacitor acts as a battery like you describe to smooth out the dip between humps.
There are half wave rectifiers and full wave rectifiers. The former only converts the positive AC to DC and shuts off for the negative half (causing flickering). The latter will convert both positive and negative halves to DC and don't flicker.
Well, LED lights are half-wave rectifiers that light up, so you wouldn’t add one. I don’t think I’ve ever heard of a half wave rectifier referred to as a bridge rectifier.
Ok, I get the gist. Thanks!
FULL BRIDGE RECTIFIER!!!11
I’ve never been disappointed with Philips. However, I have no doubt there are tons of exceptionally good quality products out there from various brands.
There are LEDs with CCD power converter. I got one 10 years ago and tested it with a 240 fps camera, no flicker at all. I will not recommend a brand because it's been years,but search for "ccd led bulb".
Also there's a number called CRI, indicating how well it represents colors. This also may contribute to your headaches. 85 or higher is good, 90 is great. Just don't trust these numbers on Amazon, the cheapest of cheap crap is marketed as " cri 90+" there.
Or scratch what I just said and find a small store that specializes in lighting and ask the clerk (or email them).
I honestly couldn't tell you. Its been so long since I purchased LEDs and the ones I bought were from the company I work for. They have worked well for me but I don't know if any brand is better than another.
I wonder if multi-element bulbs offset the phase of each element so the flickering cancels out.