Laser Gatling - getting 8 CORRECTED parallel beams from NUBM08 block

[RedCowboy]

40mm is the shortest FL and they are 53.00 each. Hmm

The problem is our beams divergence, are you talking about KE four 6X corrected beams from nubm44's with G2 primaries ? I see you said 2 sets of four......you might as well KE all eight as the bars will grow way past the height of 8 stacked ribbons in short order, by 30 feet eight might look square.

For the nubm44 with a G2 and a 6X pair I get about 6mm wide bar at the exit that tapes down to 5mm at about 7 feet then opens back up to 7mm wide at 15 feet, then by 35 feet its a bar about 15mm wide and by 75 feet it's about 35mm +wide.

What really helps is adding a beam expander to the corrected beam, I was told that using a 2nd concave cyl back to back when setting the 6X pair could tighten it up quite a bit but it's been raining here all week and I have not tested.

 

[Light superglue]

Yes at the moment I am talking about KE of 8 corrected beams from this 08 block. After making the tank turret I know that correcting beams ex G-2 after KE will be almost impossible, they can only be focused somewhere at a point.
https://laserpointerforums.com/thre...ubm44-in-lasertack-micro-module.100661/page-5

If this does not work out with 08 I have NUBM44 block from v1 to try with putting G-2 over each of the diodes. Have also a couple of v2 PJs but do not want to dismantle them yet.
KE will also be needed in order to squeeze the beams into any kind of BE later.

 

[RedCowboy]

I see what you want to do, if your 44 block has well aligned diodes it could work, but you don't really have any way to compensate if not, to knife edge on a single plane your sources will need to be properly aligned to your KE mirrors on plane ( level ) and usually this means they have adjustability built in or the individual modules and lenses can be moved to align your beams to the knife edging mirrors ( on plane ) yes the mirrors adjust but the height/plane needs to be the same for each set of 4 so the mirrors can knife edge and be aligned over the distance you want to use the beam, otherwise you may start together but deviate from there as well as diverging.

Now if they are not really knife edging but rather moveable as 8 units to bundle your beams then you could do something with that having your 8 beams all converge at your max range and if you can start with those 8 mirrors as close together as possible you will have a cluster that becomes more homogeneous as the spots diverge and overlap on the way to converge. But to get the power of 8 into the tightest beam/spot you will need adjustability at both ends or good luck with the blocks factory alignment.

But they are after all highly divergent MM beams, so the best expectations if done with full adjustability vs. one ended may not be that far off the mark, it will be interesting to see.

 

[Cyparagon]

It seems to me that after Alaskan had left the forum not many people interested in experimenting with high power are staying here...

https://en.wikipedia.org/wiki/Post_hoc_ergo_propter_hoc

 

[Light superglue]

Finaly I managed to combine all 8 beams into 1. This setup has a lot of custom made parts and Al plates to keep the frame made of 6 Thorlabs bars solid, 2 assembled Lasertack micro KE modules, 3 Optlaser mirrors for vertical shift and direction and Waveplate-PBS combo at the end.

Later I will post more pics or open another thread about it but swiftly look how tight the combined beam now is!!!
It is 5x5mm at the PBS issue and makes 20x20 mm spot on the wall at 5m away. So bad divergence was expected due to NUBM08 block with ball-lenses and also because ALL mirrors, PBS and cylindricals I have temporarily glued with adhesive tape here, not with proper glue.
Current from BST400W driver you can see is 1.99A, I did not try more yet, this thing makes a lot of light already!

 

[Alaskan]

Nice, although I don't fully understand what is going on with everything ye, but I guess you have 4 x 4 going into the PBS cube? I'd love to see a beam shot in the dark at a great distance to see if the beams really look like one beam, or if you can see it is composed of four beams on the output. Divergence can be dealt with

 

[Light superglue]

With this block I see no reason for long distance because all G-balls produce different collimation and some of the beams seem to be focused at 0.5 m and then diverge, so the faster diverging beams will always hide the well collimated ones inside of the pack.

In contrary to make a burner with 5-10m range I just need to add a focusing expander that`s it.


I have been planning to do this since many years, the long story short:

1. KE both up and down rows horizontally to make 2 square groups (left and right) well separated for PBSing at the end. You cannot PBS 2 beams if they are very close. Result on pic. 1
2. KE all vertically to reduce the gap to 4mm (this because if these were NUBM44 with collimation to infinity and not focused like these 08 with G-balls, the beams should be squares with hight 4mm and not lines like these). Result on pic. 2
3. PBS left and right groups at the end. Result on pic. 3