LH351D 90CRI Spectrum Tests

HDS has adopted the LH351d 5000k as its next High CRI offering.

It produces 300 lumens in an HDS
the sw45k produces 200 lumens in an HDS

so the LH351d is 50% brighter than the sw45k
equivalent to one hop on the HDS dial.

the LH351d is a 9050 LED with tint above the BBL
the sw45k is a 9080 (more red), with tint below the BBL

The Samsung LED still has better cri and r9 than the natural light coming in my office today:

Two measurements taken in Texas, today at 2:45PM, overcast day. First is indoors with no artificial light, only ambient light from window - the next measurement is when I step outside.

like of your anDroid ColorMeter app :+1:

good time for a dogfart :person_facepalming:

can you also show the ColorMeter data screen for the LH351d 5000k please?

Here is the Sofirn sourced 2700K LH351D

Very similar to the DigiKey one I tested but with a better price.

1Amp with Frosted TIR:

Would be interesting measure after slicing for know if DUV and CCT decrease at very low current.Cheers

Here it is sliced in a Sofirn C01S AAA small TIR on the “100 lumen” setting. Not exactly apples to apples but you can see lower DUV but not much change in CCT. I cant explain why that is, maybe LED tint variation but probably just the optic doing strange things. It’s not really meant for such a large die. There is also a little ambient light in room.

I emailed Digikey the other day to ask about some color bins, I didn’t ask for a lot because I doubted they would reply, I got the reply today :

SPHWHTL3DA0GF4WPN6 (2700K) : 798 pcs F2 W7 N2
SPHWHTL3DA0GF4UPP6 (3500K) : 759 pcs F2 U7 Q2
SPHWHTL3DA0GF4TPQ6 (4000K) : 481 pcs F2 T6 Q2

Not sure how this info is valuable though because we don’t know if the bin you tested last year were the same.

The 2700k and 3500k were always the best ones so I’m not too surprised by this.

We have seen T6 be above bbl from other vendors so it seems like these squares if meaningful generally tend to be at the very top of the square/bin

Side note; CONGRATS on getting one of these mega distributors to answer this. Didn’t think it was possible.

If I can muster up the energy I’ll test my Convoy sourced 5700K 351D tonight or tomorrow. Don’t think we have seen one of these in the “wild” yet. I think these were from some stadium lighting so I suspect mega green but we’ll see…

Thanks for all your testing contactcr. :+1:
My favorite is the 3500k UPP6 from digikey sliced.

Yeah, plus with 4000K and up the middle of the quadrangles is raised above the BBL, probably to merge with daylight tint (~ 0.0030 duv), on the other hand, integrated duv should be slightly lower than measured at the spot (but maybe not that much with the frosted TIR you used).

I was doubtful they would bother to check for me yes, I got no reply for ~10 days so I though they ignored me.


Simon wrote the bins he got and it’s Q2 (5700K) and R2 (5000K) so the lower duv bins. I have some 5000K coming (not interested in 5700K) so I’ll see how they test. By the way I measured my FC11 and it’s actually worse than yours :
5170K (Duv 0.0086)
(Ra) = 87.6 [ R9 = 30.8 ]

It’s quite strange, not 90 Ra and low R9.

Convoy Sourced LH351D 5700K 90CRI (bin: V2Q2S1)

Frosted TIR, same as before. The results are about what I expected. I purchased these mostly for two reasons: slicing and tint mixing. For both purposes they should be acceptable.

1 Amp

2 Amp

Thanks for getting those tests done! No surprises there but at least some Lee filters could help with the slight green tint.

I’ve got some incoming to see what slicing will do. Hopefully it’ll produce similar results to sliced 5000k dogfarts.


Have you got a chance to grab KD’s 5700K emitters?

Nope, I can grab one though. Any other stuff at KD I should be getting?

Actualy no. I was just curious how are their 5700K compared to the one you have. I had one installed in Novatac and it looks great. Not so “green and yellow”...

That’s why am puzzled.

Here’s the Convoy 5700K sliced in Wurkkos FC11 (shallow light OP reflector, plain lens, on high):

Good for a day time use light since your eyes are adjusted to >5000K ambient above BBL light already.

Not bad at all.

If anyone is curious what these look like under a TIR with all the phosphor removed:

450nm and 25000K CCT (if that is even a thing, I guess it is technically.)

Is this the color we saw on the first power LEDs? We all had those Ledlensers and fakes on our keychains. Stable fluorophores had yet to be found I guess. I remember, when I was in microscopy, fluorochroms had really little photon staticstics like 60000 for this green substance whose name I forgot. You could watch them fading. Or is this a completely different story?

No it’s distinctly solid blue. More like a fake UV or “blacklight” I guess but very “visible”

UltraTac A7P w/ no phosphor LHD and Sofirn C01R