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Multiple beams

Snecho

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LOL

When I build my cone of 8 beams I will have them all intersecting at about a foot away or where ever I need ( it's all adjustable ) and then I can use 8 small mirrors to reflect the small circle of beams back through the center of my rig which has open air for this purpose, all 8 beams in a tight little circle/cluster and with the right concave mirror that circle could be pretty tight...........more of a + and x overlapped where all the bars come together which means each laser would be rotated so the bars point to center.......I really want to do c-lens correction on 8 x ndb7A75's and use them in my cone of beams set up and with the right concave mirror have a nifty little circle/cluster of searing blue glory............and if the divergence of my bundle from my concave mirror is not tight enough then I will lens that to infinity point.

Note: With a concave mirror it will need to be centered and all the beams will need to be rotated so that they are all in line to center, like pedals of a flower or spokes of a wagon wheel and each beam center will need to be the same height and same .......well it all needs to be symmetrical.......with a concave mirror you would intersect the beams just after they all cross over and are expanding again........but with 8 individual mirrors there's room for slop and you can intersect the cone in or out, just align each corrected beam to the finish line/distant point from the mirror point.

With the concave it's the ring dia. to cone length that has to match the concave mirror so the position of the mirror and cone length would be adjusted to get a tight cluster/beam out.



View attachment 69021
...and that's how the Death Star was built!

:ROFLMAO:
 



Ramsey_innovations

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LOL

When I build my cone of 8 beams I will have them all intersecting at about a foot away or where ever I need ( it's all adjustable ) and then I can use 8 small mirrors to reflect the small circle of beams back through the center of my rig which has open air for this purpose, all 8 beams in a tight little circle/cluster and with the right concave mirror that circle could be pretty tight...........more of a + and x overlapped where all the bars come together which means each laser would be rotated so the bars point to center.......I really want to do c-lens correction on 8 x ndb7A75's and use them in my cone of beams set up and with the right concave mirror have a nifty little circle/cluster of searing blue glory............and if the divergence of my bundle from my concave mirror is not tight enough then I will lens that to infinity point.

Note: With a concave mirror it will need to be centered and all the beams will need to be rotated so that they are all in line to center, like pedals of a flower or spokes of a wagon wheel and each beam center will need to be the same height and same .......well it all needs to be symmetrical.......with a concave mirror you would intersect the beams just after they all cross over and are expanding again........but with 8 individual mirrors there's room for slop and you can intersect the cone in or out, just align each corrected beam to the finish line/distant point from the mirror point.

With the concave it's the ring dia. to cone length that has to match the concave mirror so the position of the mirror and cone length would be adjusted to get a tight cluster/beam out.



View attachment 69021
This a very interesting concept, I really like it! I was recently thinking of doing something similar myself. Can we refer to it as the umbrella configuration since it kind of has that look to it?
 

diachi

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LOL

When I build my cone of 8 beams I will have them all intersecting at about a foot away or where ever I need ( it's all adjustable ) and then I can use 8 small mirrors to reflect the small circle of beams back through the center of my rig which has open air for this purpose, all 8 beams in a tight little circle/cluster and with the right concave mirror that circle could be pretty tight...........more of a + and x overlapped where all the bars come together which means each laser would be rotated so the bars point to center.......I really want to do c-lens correction on 8 x ndb7A75's and use them in my cone of beams set up and with the right concave mirror have a nifty little circle/cluster of searing blue glory............and if the divergence of my bundle from my concave mirror is not tight enough then I will lens that to infinity point.

Note: With a concave mirror it will need to be centered and all the beams will need to be rotated so that they are all in line to center, like pedals of a flower or spokes of a wagon wheel and each beam center will need to be the same height and same .......well it all needs to be symmetrical.......with a concave mirror you would intersect the beams just after they all cross over and are expanding again........but with 8 individual mirrors there's room for slop and you can intersect the cone in or out, just align each corrected beam to the finish line/distant point from the mirror point.

With the concave it's the ring dia. to cone length that has to match the concave mirror so the position of the mirror and cone length would be adjusted to get a tight cluster/beam out.



View attachment 69021
Keep in mind a spherical reflector has a focal length, and as such will adjust the focus of the beams you're reflecting off of it. Need to compensate for that.
 

RedCowboy

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Yea I did this long ago with 650nm red in a cone and using pretty long FL lenses from a scope with pretty good results but 650's do have good divergence and I understand what you're saying....... the ring of beams should be as small as possible to start and the length of the cone as long as possible....or I could start with eight little fs mirrors......maybe from the m-140 arrays in a small ring adjuster I will have to make with screw adjustment blocks.

------------

I love the look of many beams in symmetrical patterns and it's worth it just for that but whats really fun is getting something adjusted then bumping the whole dam thing and knocking the lenses around in the modules, it's something we don't notice with a single beam HH but there's slack in the threads between our modules and lens barrels, anyone just wiggle your lens side to side and see.......... so a tip is lock down your focus if building a multi beam, I bought a bunch of those cheap modules from china and drilled out the heads to use as locks.....so glad the lens barrels have the screwdriver slots on their face.

SANY4862.JPG
 
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Ramsey_innovations

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Redcowboy....
there's slack in the threads between our modules and lens barrels, anyone just wiggle your lens side to side and see.......... so a tip is lock down your focus if building a multi beam, I bought a bunch of those cheap modules from china and drilled out the heads to use as locks.....
The sloppy threads of the M9x0.5 barrels have frustrated me for years! I usually wrap 2-3 layers of Teflon tape around them (not ideal but it helps). On my latest build i decided to drill out the thumb adjuster nut that's usually on the tip of the lens barrel. There's only a few threads in one of those but it's enough to act as a lock ring that can be threaded over the barrel and tightened against the module body. This way it also leaves enough threads of the barrel exposed to be able have either a thumb adjuster on the tip (so you don't need to use a screwdriver on the barrel tip for adjustments) or in my case an adapter for a beam expander. I put an o-ring over the lock ring to get a better grip on it...see pic

 
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Cyparagon

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Zoom in on your converging point and draw the rays again. I think you'll find you've made several mistakes.
 

RedCowboy

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Zoom in on your converging point and draw the rays again. I think you'll find you've made several mistakes.
Or I may use a ring of small mirrors such as those from an M-140 array adjusted to reflect either before or after crossover.

---edit---
I understand the concave mirror will de-focus the beams over distance, probably not going to use a concave mirror......really my hinged mirrors don't have to be all that small if I'm going to move them as a unit to adjust my cone, I understand alignment of each emitter to each mirror will have to be dimensionally stable in order to have the beams converge over the useful range and my hinges will need to be quite rigid and free of slack........this is still a concept in progress and on old one which IINM we have gone over before, what I am thinking about is possible but not as simple as it may seem, that said I am thinking the hinged ring of mirrors connected by linkage to a fine thread adjustment screw center located would be a fun proof of concept build.


counsD.jpeg

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RedCowboy

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The sloppy threads of the M9x0.5 barrels have frustrated me for years! I usually wrap 2-3 layers of Teflon tape around them (not ideal but it helps). On my latest build i decided to drill out the thumb adjuster nut that's usually on the tip of the lens barrel. There's only a few threads in one of those but it's enough to act as a lock ring that can be threaded over the barrel and tightened against the module body. This way it also leaves enough threads of the barrel exposed to be able have either a thumb adjuster on the tip (so you don't need to use a screwdriver on the barrel tip for adjustments) or in my case an adapter for a beam expander. I put an o-ring over the lock ring to get a better grip on it...see pic
I found my image, here's an easy way to hold infinity focus ( or whatever you want ) of your primary lens when using the Sanwu 3XBE and M9x0.5 adapter
I push my 12mm module into my heat sink and use the set screw to set the depth so the Sanwu adapter bottoms out against the heat sink holding my infinity focus of the primary lens.

1590977905009.png
 

Ramsey_innovations

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I found my image, here's an easy way to hold infinity focus ( or whatever you want ) of your primary lens when using the Sanwu 3XBE and M9x0.5 adapter
I push my 12mm module into my heat sink and use the set screw to set the depth so the Sanwu adapter bottoms out against the heat sink holding my infinity focus of the primary lens.

View attachment 69041
That's a great idea, thank you for sharing that! Unfortunately, for that pistol build I'm using a 20mm module without any additional heatsink, so that wouldn't work. But, for future builds using a 12mm module I'll have to remember that. Thanks again!
 

RedCowboy

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I just slapped this together and I still need to do the final alignment, I used drilled out module ends as lens locks to hold my infinity focus and I can slide the lens around in the thread slack nicely with these chrome/nickel coated locks, a tiny adjustment side to side at the lens makes a big difference in far field alignment.

Later I will set some optics in front of my ring of beams to bring them all together at a small point, but I mostly built this just to see the ring of beams in the night air........will have to do a smaller build with 520-525nm beams sometime as this looks really neat, these are M-140's @ 1.6a driven in series using an LM338 and a dozen 18650 cells.

When the 31,34, ect arrays come down in price I want to converge several...... should look ridiculous.

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RedCowboy

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These used diodes have been fun, you can pick up these old projectors really cheap if you look for a bargain ( 2 out of 4 played good ) and if you want to power up the KE array before you harvest, the diodes are in series, 3 strings of 8, there's little test points on the ribbon marked K1, K2, K3 and A1 A2 A3 for cathode and anode, cathode is negative and anode positive, limit your current to 1.6a - 1.7a and it will draw about 37-38v each string, it's best to use a separate regulator for each string which is what the projector did to avoid one string drawing more than another due to diode inconsistencies.

----edit----

Has anyone ever re-drilled the factory lens plate for M9x0.5 ? I think the factory KE setup is pretty crude/loose and would likely fly with even a bunch of 3E lenses or the least expensive single element of longer FL I can make use of.

SANY4975.JPG


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RedCowboy

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Just lazing around with these inexpensive diodes, everyone feel free to post any multi beam builds or pics you have. :)
I think a better way to do this will be to drill pin holes in an aluminum plate and use indium foil to pull heat off the diode backs, that way they all mount flat, then drill and tap a lens plate threaded for M9x0.5 and the ring of beams can be reduced via. telescopic reduction if desired.........yes a knife edge set up is still the industry standard for bundling beams but for asthetics in a handheld a ring of 488's or 505's would sure look neat all running out appearing to end together in the far field.

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