New "Custom 5050 Red 620nm LED"

Flashlight Modding and DIY Parts
1

I found this Custom Red 5050 LED on Kaidomain and just received a sample for testing.

Initially purchased some to test in the Convoy H1 headlamp, but they haven’t arrived yet, so I installed one in the Convoy L21B. Just waiting till dark to see what it’s like.

Started off with Convoy’s 5A driver which is actually running at 5.5A for 460 lumens, then decided I better try something lower in case it’s being overdriven. Installed a 12*7135 driver and started removing chips

4.2A - 520 lumens
3.8A - 515
3.5A - 506
2.8A - 440

Specsheet is rated 3A max. I started off at 5A since the review on Kaidomain says it handled 6.7A fine.

Looks like 3.5A is the sweet spot.

I’ll test range tonight, but this is quite a decent chip, since it doesn’t require a special driver like the Osram Red. Great for lighting up a larger area.

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2

Too bad they don't have 660nm version

3

How much of a lumen reduction would 660nm be? I’m sure a darker red would reduce performance significantly.

4

Not much that you'd be worried or notice (some of us)

Unlike 620nm, 660nm has some more weight in regards eyes healing and not to mention not detectable by some animals like 620nm is (as per several hunters feedback I got)

5

According to Osram Color Calculator, 10 times less :open_mouth: (I generated a 620nm and 660nm of 1W radiant power, got 216lm and 22.6lm)

6

Ouch!

7

Thanks for your input, I’ll just stick to 620-630nm if that’s the case.

8

This LED looks exactly like this old post

I have asked Kaidomain if theirs is Epileds, but their response was no. I reckon they just don’t want to tell me because its appearance is 100% identical. The only difference is that this has a forward voltage of 3-3.7v, whereas the Epileds is spec’d at 2.2-2.4v

9

Gents let's not jump to conclusions. I have 620nm XP-E2 and 660nm XP-E2 and I must say that Osram and Cree Color Calculator is not correct in this case.

I do not see any output drop as stated by Freeman!

What can be explained by these numbers is 730nm which is so dim that it's hard to use.

620nm and 660nm doesn't have such a big difference.

10

Actually I made a mistake, Osram Color Cacl generates a pure color LED from a dominant wavelength not peak, dominant is the color that appears to the eyes, for a red led the peak will be at a higher wavelength because the eyes sensitivity decrease as wavelength increases, anyway I generated sources with 620 and 660n peak this time and got 262 and 64lm, so about 75% reduction.

11

No difference at all to the eyes ?

It’s annoying because Cree use luminous flux for red and radiant flux for photo red so we can’t directly compare the numbers.

12

I will post photos of 620nm and 660nm next to each other next week when I get home, but believe me it's not that different as in your calculator for sure...

EDIT: just to speed up the resolution and Funtastic doubts, check Sofirm C01R posts and tests ....

13

I think I see the dome overthere! Even from XP-E2 I removed dome for better thorw…
Osram red is not bad, I just use 3.2V driver for them, stilll no died leds.

14

Visibility is highly increased at 620 nm, but it’s not a “deep red”. Looks a little orange to me, so I would not be interested. It all depends on the use case.