Luminus SFT40 test

[QReciprocity42]

@koef3

I already thought about this and also imagined some sort of semi automated desk-sized small production line for very own custom made LEDs (with 3D printing and less expensive CNC this is not as unrealistic as it seems)

But the main problem is to get the raw phosphor mixture and the proper silicone/epoxy coating, which is needed here. Salvaging 12 LEDs for just one emitter is way too expensive.

This would be a sick project!

@DesertSnake

I looked at the prices for phosphors and was horrified, thousands of dollars for few gramms

And so you came up with a great idea, if the blue peak is approximately the same from different manufacturers, then this method can work, but need thinner equipment and a cleaner place to make the modification efficiently. I would send you this diode, no problem at all, but now parcels have become very expensive, I usually send something abroad in a large pile to one of friends and then he sends it to other places

I like this idea because many high CRI LEDs (like the Moonleds previously tested) are limited in performance by the underlying blue die. But as you both pointed out, sourcing the phosphor in a cost-effective way is a limiting factor. Please keep the diode–I do not have the appropriate equipment to perform measurements, but thank you for offering!

I have recently been messing with UV resin as an optical adhesive, specifically using them to re-dome dedomed or sliced LEDs. So far the resin seems to be stable under the flux density and temperature of an operating LED (no yellowing after a month), the main weakness is that the resin can detach during reflow, due to thermal stress. I think LEDSupply used to sell “LED Seal” which is a silicone sealant designed for this type of stuff; if one were to perform these modifications on a large scale, the adhesive won’t be the limiting factor, but the phosphor.

I’ve accidentally de-phosphored 2 519As, and detached the entire die on another one, while trying to pry off the resin. But the nice thing is that the entire phosphor comes off intact with the glass layer, and I could try to transplant the phosphor on a high-performance die to see what happens. I’ve got a 50.2 but it would take 4 519A dies to cover; I do have a random collection of 3535 LEDs but they are fairly outdated.

I tried to build a PC green LED by using green glow powder as the phosphor, but the powder is quickly overloaded by the flux density, going dim then angry blue. The resin seemed fine.