Playing with gang lens of PLPM4L MDP chip

[Light superglue]

This is to continue the old thread with proper name of the chip what was not on ebay 1 year ago when I got it from taobao and started playing: https://laserpointerforums.com/threads/osram-60w-multilaser-chip-with-24-beams-jlm450nm.106325/
Now its commercial name is PLPM4L.

In an attempt to make beams parallel from this MDP (Multi Dye Package) I took off the gang lens and installed it on a custom made 2´´ Al round into Thorlabs slip plate positioner allowing to shift 2mm along X and Y axes.
Then tried to find a good position shifting all ways (circular and along Z axis as well) but all I could get was separation of lines at the wall while all beams became not parallel any more.

This means that the gang lens is at optimum position and there is no use to remove it.

 

[Alfendalf]

Wow, this is incredible, you're doing great.

 

[Light superglue]

Now I did similar experiments with NUBM35 MDP chip.

But all pics are in the thread about NUBM38 (which is almost the same as NUBM35):

NUBM38 75W MDP chip focused at 5m distance

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...

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[aaronnoraa]

So I'm guessing that this has shown that the diodes themselves are mounted at angles to one another, not parallel, making it impossible to remedy for a bad array?

 

[Light superglue]

Yes, impossible for this array because there are no such small lenses to put over beams.
However maybe possible with bigger MDP like NUBM36. The problem is that optic shop in ali which is selling small lenses does not answer my questions...

 

[kecked]

You’ve got my interest in trying a knife edge of all rows. Are the beams precise in orientation to each other. Ie well spaced and parallel? Want to see if a single mirror on an angle could knife edge all the rows into four beams. Now it’s just two pbs cubes and one final knife edge to get a single beam.

 

[skijohn]

"beams precise in orientation to each other" I don't believe they are and that is the problem he's running into and unless the diode output of each diode could be adjusted independently I believe bring them all together will be very difficult if not nearly impossible without a lot of apparatus involved, like collimating lenses for each diode as well as independently adjustable mirrors for each diode to bring each collimated beams parallel to each other? No matter what approach is taken, it will require a significant amount of light manipulation to bring all the diodes output to one spot?

 

[Light superglue]

No, what I thought to try was to obtain lower divergence of the pack as a whole than it is now with the gang lens in place. Without any collimators, KE or such but by expanding each beam so it would touch the neibouring beam.
Just need long and very thin cylindricals with pretty long focal distances and such things are not sold anywhere.

 

[skijohn]

Large cylindricals at 90 degrees from each other was the idea I proposed in a different thread where someone was working with an MDP (Multi Dye Package)?

 

[Light superglue]

Maybe you have suggested it as well, I do not remember.
The only thing I can find now is that first time I have suggested it here (post 11) but no one seemed to be inspired.

NUBM31T 95W 455nm

Hi, Found this on ebay. https://www.ebay.com/itm/Nichia-NUBM31T-455nm-95W-High-Power-Multiple-Laser-Diode-Chip-Package/173962238656?hash=item2880f51ac0:g:~LsAAOSw3zldKEwU Ofcourse the price is a little problem. What do you think? Didn't looked in datasheet but imagine this in a host :eek:.(It...

laserpointerforums.com

The problem here was that small cylindricals are produced with short f, and big cylndicals with long f. So I do not know where to find small (thin) cylindricals with long f. One could try to cut them but precise cutting of glass is a very complicated and tricky thing. CDBeam has written about it in one thread not long ago.

 

[skijohn]

Yes, I suggested it here...

NUBM31T 95W 455nm

Q's are overpriced junk.... maybe NDB7875's inside.

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