CREE - Dome removal

[BPH]

I am building some custom lights and plan on using the Cree chip.
Several people have commented on the dome falling off and this would not be a good thing to happen at the wrong time. So, why not just remove the dome? I imagine that is blocks some light anyway and if inside a sealed (waterproof) light housing, why would one need the dome?
So, the questing is, can anyone see a reason not to remove the dome in this situation?
Thanks,
BPH

 

[carbine15]

the dome protects all those little wires from breaking if you drop the light or sneeze on it?

 

[MatajumotorS]

i had removed the dome - not good

the beam was dimmer more artifacts etc. then i removed the metal ring, then more light was captured by reflector, but even more artifacts and big posibility to damage the thin wire from die.
I think it is not good idea to remove the dome ...

maby later some pics.

 

[fineday]

I know some of my friends on the forum have tried to remove the dome, but as MatajumotorS said, the LED without dome gets dimmer very quickly, and soon it deads.
But if you put something else to protect the exposed core after removing the original dome, seems it would work probably.
After all, I think to remove the build-in reflector is much more useful. I've read some threads, it is the build-in reflector that causes the bright ring or dark ring in the facula.

 

[cqbdude]

Mine came off by itself....I just pushed it back in....

The beam is never the same again after that...

 

[carbine15]

try a glue of sime kind. like a silicone adheisive that's clear. That'll glue it back and there's a chance that it'll be clear enough that it might not have artifacts. I'd say let it dry completely before firing it up though.

 

[soffiler]

The dome and the silicone beneath it are there for some very good reasons:

- to protect the die from the environment, which in a manufacturing situation may include wave-soldering

- to aid in light extraction; the intimate contact between the silicone and the die acts like a TIR optic

- to a large degree it controls and shapes the light output pattern

- compliant silicone allows for differing thermal expansion of the various materials without building up mechanical stresses

 

[BPH]

soffiler,
Thanks for the info. It just happens I called Cree an hour ago, and they said exactly the same thing. I didn't know that there was silicone under the dome, but it makes perfect sense that there is (like the Seoul and Lux LEDs).

The Cree engineer said if you put excessive force on the dome and break the seal with the silicone, you could have some problems. He also said that the Cree chip won in a competition with Lux and others for the new Boeing 787 wing tip lights due to much better reaction to thermal shock.
-BPH [font=&quot][/font]

 

[65535]

Cool Info BPH!

 

[MatajumotorS]

pictures