Nichia 144A series, an output test of a 6500K 70 CRI sample. Nov 7th: added a test of a 5700K R9050 version of the 144A

Here’s a dedomed (and wrecked) 144A next to a dedomed (sliced) 219C, and it appears indeed 4 219-size dies.

I updated the OP with a new test of a Nichia 144A 5700K 90 CRI led.

Strange phosphor coating on that 90+ CRI version!

@ Djozz: Try to bring up the current to at least 10% below the rated current.
All Nichias CRI90+ especially the Ra9050 and 9080 have thicker phospor layers. Seems they need more photons to energized correctly. The 6V needs a minimum 1,4A while the 12V needs a minimum 0,7A. The spectral testing by Maukka confirmed this too.
They also need heavy diffuser or hybrid reflector/collimator or faceted colour mixing TIR optics for narrow beam applications. Otherwise you’ll get the sunny side up for breakfast.


Multi die LED always comes with problem eh?
With XHP50 and XHP70 we got a donut, now 144A give us a spiegelei. Perfect combo for a breakfast! :person_facepalming:

What happend? It died?

It did, at 7.4A . I wrote it in post #4 but I should add it to the OP as well. So I used the dead led to remove the dome in a crude way to have a look at the die size.

Ah, ok. It would be interesting to see how de-doming changes the beam and tint of the high-cri versions.

I’m highly sure it will lower the CRI significantly and change the tint to cool white since the phosphors would likely to stuck to the silicone dome. Unless we can carefully separate the phosphor from the silicone dome. Or….make a clean slice and leave only thin silicone over it. Will try it later or…. ehm….Djozz? :wink:

Yes, I can do a shave on one of them, but do not expect miracles, the light intensity and throw increase will not be as spectacular as a full dedome, and on top of that, the ‘photon recycling’ process works better with cool white leds that remain a strong blue component after passing the phosfor layer.

Damaging the phosfor layer will of course be bad for tint and CRI.
However, if the phosfor layer stays intact, dedoming does not decrease CRI enormously, a good dedome will shift the tint to warmer, but from what I have found, a nice CRI led will never get a bad tint upon dedoming.

Yes, I know all of this. I am interested in the effects it has on this specific led. For example does photon recycling reduce the yellow spot effect? Does the light quality change in unexpected ways (the dome has extra phosphor in it?).

Thanks for your efforts ;).

From the picture, it seems the phosphors isn’t mixed in the silicone dome. Slicing won’t remove the phosphors
sm305 Ra9050 vs sm653 Ra7000

As PM-ed as well, I checked at 1400mA (and so did clemence), the ‘spiegelei’ problem (funny that you know the dutch word for egg sunny side up :smiley: ) is not current related, so it must be uneven phosfor deposition during production. It is seen in several 6V high CRI 144A sample leds that clemence has received, but not the 12V ones. Clemence is checking with Nichia about it.

Hopefully this is only sample defect. So far only the AME (6V) has the egg yolk problem. It’s not cool to import hundreds of egg yolks all the way from Japan, we have plenty down the local market already.
Of course I know what is spiegelei (spee-hae-leey) :laughing: , dutchmen were in my country for 350 years. Many words in Bahasa language derived from Dutch too. I’m also 12,5% Dutch (according to Mendel’s theory).

HAHAHA, you guys are killing me.

That sm305 Ra9050 Spiegelei looks tasty though!

It’s the sm575 Ra9050 beamshot Chouster, will test the sm305 later. I don’t really remember what it was like.
Now you made me realize the macro pic of the sm305 indeed makes me hungry

Yup, it’s the macro pic and that tasty looking spiegelei color of that sexy looking Nichia sm305 Ra9050… :slight_smile: Also the X pattern appears to be hidden better with that thicker phosphor layer…

Shpee gull eye :slight_smile: (German pronunciation)

GOOD NEWS: The new batch of 6V 144A don’t have the spiegelei problem/donut/”X” artifact














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Testing the Red


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And lastly: An Emitter Porn for you

Cool, no more egg yolk. :+1: