Got a couple of 4000k 70.3 90cri from kaidomain off aliexpress
Installed one safely in a dive torch and its exactly like turning on a household light.
Then I had to transfer the other to a specific pcb and I’m pretty sure I roasted it and it popped during electrical testing.
Now to consider buying more leds and upgrading my soldering and lack-of-real-hotplate situation.
newly released Element Cree XEG
Did you center the die on the MCPCB? Why are there gaps in the copper around the solder pads?
I installed and measured XHP50.3 HD (sliced) 80 CRI 4500K and XHP50.3 HI 90 CRI 4500K from mouser.
I’ve been using a 3v 50.3 lately and thought I would try slicing the dome out of curiosity. Lowered the CCT from 5800 to 5000. The CRI went down (70 to 67) and the DUV went up (from 0.0021 to 0.0081).
It’s much less visually appealing now. More yellow/green. Oh well.
This is extremely surprising to me! Generally the green goes down when you slice, it doesn't quadruple! Got any pictures?
Indeed! I have a couple more on the way to retest. I’ll get picture this time around.
One thing I noticed while slicing the dome was the dome itself looked different than most emitter domes I’ve encountered. It almost had a refractive quality to it. Unfortunately it went flying across the shop into the abyss. Oh well. I’ll document it all with the next emitter I recieve.
I would absolutely love to see the pictures from your next test! Hopefully they will demonstrate the refractive quality you described.
The only negative dedome experience I've had was 3V XHP50.2, which turned green after dedome. It is not surprising to me because the phosphor pour is very different and extends way past the underlying blue chips, so any theory about dedoming a typical emitter (phosphor exactly over blue chip) goes out the window. Dicing it up (removing the excess phosphor past the blue chips) removed the green.
Your case surprises me because as far as I can tell, with the 3rd gen XHPs, the phosphor pour is exactly over the blue chips and does not extend beyond, so the phenomenon I described with the XHP50.2 should not be happening.
Green eggs and ham.
Maybe it would help if you remove the yellow phosphor around the die (‘slice and dice’). A minus green filter would help for sure but it also reduces the output. Glass lenses with green AR-coating are useful, too. Some 3V XHP50.2 really have a nasty green and swapping the led is also a good solution.