MC-E without dome die size pictures, and beam shots.

[liveforphysics]

I ordered a bunch of MC-E's from Cutter. Now I'm playing

I removed the dome from one to reduce the appearent die size. You can see it is about ~75% shorter on each side, which would cut the surface area in half. This would make the intensity double (all things being equal), and would enable twice the candlepower when used with the same aspherical lens vs a MC-E with the dome.

To remove the dome, I simply applied gentle pressure at the base with a pair of wire nippers until the dome lifted off. Easy as pie.

I also threw in a crummy blurry picture of an MC-E sitting on a P7. I no longer like the P7 after playing with the MC-E. The flexibility of indivdual die control is much better than the P7 setup.

The intensity is so great, both your human eyes and the camera both over expose the beamshot with a 3" aspherical lens.

This is taken with the camera way underexposed so you can see that the removal of the dome still creates a clear projection of the dice. The image is kinda blurry from trying to hold the lens in one hand, and aim the camera with the other.

Im building some aquairum lighting, and the amount of light I get from 24 MC-E's is pretty impressive, but sadly I'm still not reaching even half the levels I had with my previous metal halide lighting.

 

[Gryloc]

Thanks for "opening up" one of your MC-E emitters in the name of science. :bow: :bow: :bow:. Saabluster plans on doing this as well. Well, I was hoping that removing the dome could reduce the apparent die size. I am glad to see that doing so does not destroy the emitter entirely like it does with some emitters (due to sheared bond wires). The apparent die size looks much smaller (I wonder how the dome-less MC-E compares to the small-ish apparent die size of the SSC P7), but I hope that there arn't too many ugly artifacts caused by the goo-ey silicone under the dome. I bet that could be cleaned up a little, just to make the soft silicone appear more uniform.

-Would you be able to compare the brightness of a MC-E with and without the dome? I measured about a 30% reduction in brightness of an XR-E after the dome was removed.

-Could you take a beam shot of an MC-E behind some sort of throwy reflector, and then show a beam shot with the dome-less MC-E behind the same reflector? It would be interesting to see how that would affect the beam size and also the concentration. The more intense beam may have its advantages, despite the possibility of a reduced lumen output. I wonder how the image size affects the appearance of donut shaps in the beam.

Thanks again, and good luck with your aquarium lighting. That would be a lovely, albeit painful, sight to see when completed! :duck:

-Tony

 

[Flashlight Aficionado]

Could you place a reflector over the domed and undomed MC-Es? Then do a comparison beamshot. Do NOT clean up the undomed LED. I also want to check for artifacts.

"If" the undomed MC-E was cleaned up, could we re-phosphor it, if some was removed accidentally?

:thanks: liveforphysics

 

[maxspeeds]

Interested to hear if anyone has successfully re-applied the dome to an MC-E?

 

[2xTrinity]

I accidentally sheared the domes off my Tri-MC-E 2C Mag recently. It was fun while it lasted. They're sitting in my "junk drawer" awaiting a future project.

One of the reasnos why those domes are used is that they aid in lumen extracting by through a process called index matching. While the apparent die image of the "sheared off" MC-Es is a lot more, overall output is less as a lot more lumens are lost due to internal-reflections along the no-longer-nice-and-smooth interface separating the LED from the outside world.

I'm toying with the idea of index-matching the MC-Es to some TIR optics using microscope immersion oil. In the process, I will lose the use of the convex lens inside the optic, so the beam profile will become more like a standard reflector with spot + spill rather than all spill. However, my theory is that this approach woudl offer the best of both worlds -- the improved lumen extraction of the stock dome, AND the smaller apparent die image inside the reflector.

 

[Sgt. LED]

I though of trying the oil between emitter and optic but I left it alone after trying to figure out how to keep it in there. I could not maintain a perfect seal during use. Leaks!

I hope you can have more success than me, I can see it being easier with the MC-E. I was using a Q3 and a Surefire TIR optic.