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NUBM38 75W MDP chip focused at 5m distance

Light superglue

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Not sure if anyone is still interested in powerful lasers in the current political situation, but I have more pictures today.

Here I have purchased NUBM38 which is smaller than NUBM31 and it also produces a smaller spot on the wall while its 75W power is not much less than 95W.

If the beam is passed through the same 5.1x beam expander which I have made for NUBM31 the spot at 5m is clearly less than 10x10mm (pictures done at 0.5A current).
And here all the expanded beams fit into the big PCX lens.
The spot of 38 without expander was 40x30mm.
 

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CurtisOliver

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Nice to see you light superglue :)
I'm quite interested to know if the power density is actually better despite the 20W decrease. That's a pretty good spot size for a focused multi-mode array. One thing for sure, that must be devastatingly bright.
 

gazer101

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I find it oddly satisfying to look at well focused laser arrays
 

Light superglue

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Gazer:
Spot pics are made through OD6 googles.

Curtis:
Yes, I checked it focused at 20cm to cut stainless steel (at 3A current) - it cuts but not as fast as 31T, so it looks that power is important (even if not as good focused) to heat adjacent areas of the heat conducting metal.
I have also tried NUBM35 - it had worse parallelity of beams (spot was 5x4cm without expander) and did not cut trough SS as fast as 38.
But at 5m with expander the spot looked as tight as from NUBM38.
Now I am trying to find the right driver, the dedicated driver from ebay/taobao (booster from 12V) died after less than a minute of work, it looks that the capacitor E5 has burned.
 

Light superglue

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Here I took off the gang lens of NUBM35 (which is constructionally similar to NUBM38 but was a little cheaper and less precise in orientation of the beams) and also removed the metal cup where the gang lens was atached to. Unfortunately it was also holding the glass window, so all emitters are open now. This also gives more space to play with different lenses.

First I attached the gang lens to an Al round holder similar to what I used with PLPM 4L gang lens here:

in the same slip positioner but the result was not good either - I could not find a better position to concentrate beams compared to what was there originally.

Then I replaced the gang lens with 4 cylindrical PCV lenses from smallest sets which can be found from techhood on ebay and the output were 2 horizontal lines on the wall at 5m. But they were pretty far away from each other I think because the centers of the lenses were not corresponding to the centers of the beams (8mm separation vs 6mm separation).

Now looking again for thinner cylindricals. I found a shop in ali which has same size (and more) cylindrical lenses as Thor is selling but they are uncoated and cheaper. But this shop is very slow in responding to my messages...we will see...
 

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aaronnoraa

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Here I took off the gang lens of NUBM35 (which is constructionally similar to NUBM38 but was a little cheaper and less precise in orientation of the beams) and also removed the metal cup where the gang lens was atached to. Unfortunately it was also holding the glass window, so all emitters are open now.
Yikes, since it's 445nm I'm guessing that glass cover was providing a hermetic seal? If so and they're now open, that array is going to degrade FAST. Sorry to hear that..
 

Light superglue

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I think it depends how ofen they are used. I have NUBM05/6/8 with ball lenses removed in 2016 an they are still fine.
Of course I only had them on maybe 10 minutes in all the years...
 




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