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ArcticMyst Security by Avery

Going to make a 1.4W-2W 650nm array

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So I'm going to make an array of 7 650nm laser diodes for a bit of fun.  Total power out will be between 1.4 to 2.1 W depending on which diodes I use.  I'll use a copper disc with bored holes to fit the heads from the 7 axiz modules.  Will be a good heatsink which will be coupled to the body which will be some kind of aluminium tubing or perhaps torch host.

Of course its unlikely that the beams will all be exactly parallel, but it should be interesting none the less. It have the holes bored parallel, but none the less it would be difficult to have everything totally parallel.  I figure a few 18650 Li-ion as power source.  Driver wise I haven't made up my mind yet - suggestions? Current requirements will be anywhere from 2-3Amp.  :eek:

From a distance the net effect on the eye observing will be about equivalent to a beam with power of ~1.4-2W.

What about one of these for a host? http://www.dealextreme.com/details.dx/sku.12325

Edit:  Maybe use a telescope system to 'un-expand' the 7 beams into a tighter focus.  A couple of AR converging lenses should to the trick.....Either condensers or aspheric type AR coated lenses. Magnification of x10 will be about right as the input 'beam' is 25mm diameter.
 

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I'm not sure I get the point - this is entirely just for sh*ts and giggles? I think it would be more useful to combine them in a way that you'd actually get a concentrated beam in the end instead of a few dots

like this ;D
3121P9293255.JPG
 
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Nice picture, a little hard to see what going on there at first glance.   I can't think of any good/compact way of combining more than two beams of the same wavelength so this is just for a bit of fun.  Mainly.

Actually, I think I can see whats happening.  Staggered arrays with spatially offset turning mirrors and then a final telescope/converging lens system. Looks like use is being made of thin film polarisers and half-wave plates to rotate the polarisation. I'm slightly surprised it produces an output beam that looks that good. What are the characteristics of those two lenses? Are they aspherics? The collecting lens takes in parallel ray 'bundles' from a source at 'infinity' and focuses them to a point and then demagnifies the beam with the final lens, effectively squeezing the separate beams together.

Looks like the two banks have orthogonal polarisations and are being combined in a rather large polarising beam splitter cube.

I may be able to use a similar telescope system to decrease the separation between my beams....but I would need precise control over each lasers pointing direction which I won't have with the solid copper heats sink arrangement.  Worth a try though...
 
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Damn, that's an awesome picture MarioMaster! Do you have any more info on what's going on there? Apart from a ton of red diodes being combined in to the one beam, I think that's pretty clear :)
 
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Nice, M.M.H.L.D. (Multimini highpower laser diode !!) Curious.. what is the output in mW? what kind of diodes are they? How powerful is the focused beam?

more pictures please :)
 
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LikeitBright said:
So I'm going to make an array of 7 650nm laser diodes for a bit of fun.  Total power out will be between 1.4 to 2.1 W depending on which diodes I use.  I'll use a copper disc with bored holes to fit the heads from the 7 axiz modules.  Will be a good heatsink which will be coupled to the body which will be some kind of aluminium tubing or perhaps torch host.

Of course its unlikely that the beams will all be exactly parallel, but it should be interesting none the less. It have the holes bored parallel, but none the less it would be difficult to have everything totally parallel.  I figure a few 18650 Li-ion as power source.  Driver wise I haven't made up my mind yet - suggestions? Current requirements will be anywhere from 2-3Amp.  :eek:

From a distance the net effect on the eye observing will be about equivalent to a beam with power of ~1.4-2W.

I'd seriously be using a TEC with your proposed project... you are going to need cooling on top of your copper heat sink!! It is going to get HOT !! :eek: :eek: :eek:

What about one of these for a host?

Edit:  Maybe use a telescope system to 'un-expand' the 7 beams into a tighter focus.  A couple of AR converging lenses should to the trick.....Either condensers or aspheric type AR coated lenses.  Magnification of x10 will be about right as the input 'beam' is 25mm diameter.
 
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Well the copper slug will be excellent and spreading the heat and the body of the host will be thermally connected and considerably massive so I anticipate several minutes run time before it gets a bit warm.

I count 24 LD in that photo.  It we assume 300mW each then thats 7.2W total output.  Factor in numerous optical losses and maybe its something like 5-6W output depending on the optical coatings being used.
 
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No way all those diodes are running at 300mW. I haven't seen a red diode safely run at 300mW before, you'd need a duty cycle. And in a setup like that, no duty cycle would be preferable.

Realistically, they'd be running at 200mW max. 4.8 watts. Optical losses, probably more like 4 watts.
 
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I think that laser rig in that picture was a bunch of lasers spaced next to each other, not "combined" into a single intense beam since that just doesn't work.
 
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Well, depends how you define 'combined'. They wouldn't be combined, with like a beam splitter or anything. They are just all beams next to each other.

But, once you focus it all down, you wouldn't be able to distinguish one beam from the other, so it would effectively be the one beam, just with a larger beam diameter :) Like in the pic :)
 
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Yes, the beams are like a bunch of straws bundled together. The telescope simply demagnifies the bundle further 'squeezing' the bundle together. Beam quality is likely pretty poor. You could do a bit of spatial filtering with a pinhole but you would loose most of your light.
 
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seems like you know your stuff ;)

I believe the unit uses 200mW red diodes and has an output of around 4 watts, the beams are all bundled together and then the large two groups of beams pass through a polarized beamsplitter cube and then the resulting beam is then shrunk with a set of collimating lenses
 
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MarioMaster said:
I believe the unit uses 200mW red diodes and has an output of around 4 watts,

Murudai said:
Realistically, they'd be running at 200mW max. 4.8 watts. Optical losses, probably more like 4 watts.

[smiley=happy.gif]
 
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Yeah, 300mW/diode is optimistic but I only suggested that as an upper limit because I know if I was building a system like that I would use the most powerful 650nm diode I could get my hands on.  300mW is currently where its at afaik.

I have a couple of physics degrees. ;)
 




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