Bright diffuse LEDs

Anyone know a good reliable source (I’m in the US) for bright, diffuse, inexpensive LEDs? Tayda has “superbright” and “ultrabright” ones but they’re water clear lenses and project mostly in one direction, so if they’re adequately bright off axis then they’re blinding on axis. On the other hand their diffuse LEDs require more current than I’d like, e.g. the green A-1553 I think needs about 470R series resistance with 5 V for a good brightness, and that comes in at about 6 mA. Several of those add up fast.

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If you have a suitably bright LED that otherwise suits your purposes, perhaps an adequate solution would be to use a home-made diffuser. Perhaps a small patch of bubblewrap or a dab of clear epoxy. Even art-quality tissue paper could be effective.

Edit: test your solution for safety. It isn’t a good design if your diffuser melts, emits toxic fumes, or burns the house down.

PS: And besides, I live on a different continent. You can’t prove I made you do it.

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Have you tried just rubbing one with sandpaper until it looks opaque-ish…?

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I haven’t, but they’re rounded so getting a good uniform sanding wouldn’t be that easy.

I did think of putting them behind the PCB with translucent areas but not sure that look would be what I want.

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I gotta say, I’m a big fan of that approach. You can then play around with having the labels backlit and I think it looks quite nice.

That said, I really like these diffused 3mm LED’s I get from AliExpress and they come in 5mm too, I think. I’ll add a link later.

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I have played around with sanding LED’s with marginal success. It seems that even when sanded down the clear/white type still tend to be pretty eye piercing.

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It’s probably too much of a hack for you, but I just use hot glue or tape to diffuse the light. But I also can’t stand too bright of lights.

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The so called fog LEDs listed here look to be diffused and, if the numbers are to be believed (which they aren’t), brighter than the regular ones though much less bright than the “white” ones.

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The 3mm flat top ones I like are these:

And this appears to be the equivalent 5mm ones:

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For my Turing Machine build, I just sanded the Tayda LEDs flat and flush mounted them. They look pretty good this way, but using those that Christian posted would probably look better, and also less work.

I do want to update the rest of the LEDs in my case to look like this, now.

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Can’t see myself switching to flat top at the moment. Same vendor does have round ones though.

You’re a more ambitious person than I. Or you were the subject of some strange conditioning as a child.

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I got some green and some red ones.

On the left the AliExpress green LED, on the right the Tayda A-1553. Of course the photos don’t accurately reproduce how they look in reality but you can get an idea:

The AE is diffused and is brighter than the Tayda but not blindingly so on-axis — but only because while the series resistance on the Tayda is 2k, on the AE it’s 60k. (Power supply is 12 V.)

Forward voltages are 2k for the Tayda and 2.2k for the AE. So current, with the above resistances, is 5 mA for Tayda and 0.2 mA for AE.

I’d say to make the brightness roughly comparable to the Tayda with 2k, the AE needs about 160k.

The AE is also greener than the Tayda. I never thought the Tayda looked un-green before, but next to the AE, it definitely looks a lot more yellow.

One drawback is the leads are shorter on the AE. The Tayda’s leads are just long enough that you can solder one next to a 1/4" closed jack and it’ll reach through a hole in the front panel. The AE LEDs would need to have their leads extended to do that.

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I use the clear Tayda ones, not the green tinted, so they may be different. I have some of those flat top ones linked above on the way. I will post my comparison once I have them.

As noted above the clear Tayda LEDs throw the light mainly forward, on axis, so to get what I’d consider a decent brightness off axis you have to make the current high enough that they’re blindingly bright on axis. There’s less difference on and off axis with these diffused LEDs (though they’re still a good deal brighter on axis).

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Here are some resistances for (very) roughly similar brightnesses (to my eye) from the standard Tayda LEDs and the ones from AliExpress:

LED vendor type color SKU V R
Tayda diffused green A-1553 5 470
" " " " 12 2.2k
" " red A-1554 5 3.3k
" " " " 12 15k
AliExpress YuanQi AI fog green - 5 39k
" " " - 12 150k
" " red - 5 6.8k
" " " - 12 22k

I used the AE LEDs on my clock module. The supply is 5 V, I used 6.8k for the red and 39k for the green, and I think that looks good.

Extending the legs to reach the jacks PCB is a pain, though, and I’m considering building a module that would use 11 of them. Ugh. I’ve found what look like similar LEDs but with longer legs from a Hong Kong vendor on eBay:

I have these on the way.

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Make sure you keep one hand in your pocket when working with such high voltages. :stuck_out_tongue:

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Oh sure, spot the typos four months later, when I can’t edit them any more.

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This looks great. Normal bright LEDs hurt my head.

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Don’t think of them as “bright” (at high current). Think of them as “low current” (at reasonable brightness).

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I got the eBay LEDs today. The images below only vaguely resemble how it looks to my eye, but…

With equal resistances, to me the red is close to the same brightness as the AliExpress “fog” LED. The green is about the same on axis and significantly dimmer off axis. I think going from 150k to 120k (with 12 V) gives a pretty good result, a little brighter straight on and a little dimmer to the side. The leads definitely are long enough to span from panel to jacks board.


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