As you can see this led has been dedomed inproperly
Ugly blue
The phospor is clearly damaged. Dont worry though this is just a lattice bright xpe fake i tested on.
Get a led cob of your choice and cut a small square of phosper off of it. These cobs are cheap and plentiful. I only had cool white so the resulting color of my led is cool white.
The square of phospor is glued on with sillicone type 1. You may also need to stack the phospor.
The fix is done. Its pretty ugly but would probally look better if i had cleaned off the remaining phosper on the led and used a better led cob.
Also im using cree 100w warm white lights 2700k
I don’t think you could fix a failed dedome like that, it might have “fixed” the beam a little but once the phosphor has come off the emitter its basically to throw away.
More testing needed but i think with better phosper i could “fix” it
Worth a try.