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Experience with 50W chinese YAG modules?

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Q-switch would definitely still be useful. Can't comment on the mirrors because I don't know the specs on them. Depends on what sort of cavity you want too. There's a couple of folk on here with experience in building/repairing high power YAG lasers, they'd be able to offer some tips.

FYI, your diagram has a small error.



Red: 1064nm
Orange: 1064nm+532nm
Green: 532nm

It's not a whole lot cheaper, at least not if you're buying new parts. You'd still be looking at >$1000 to build a 3W 532nm unit from scratch using new parts. Probably >$2000. You can bring the price down considerably by buying used/surplus parts from places like eBay if you have some patience.

It's cheaper just to buy a unit from a supplier in China until you start getting into higher powers or you need really good specs, SLM, small beam diameter, good divergence, low M2, that sort of thing.
Aha! You got a point there. Looking over yours, it makes perfect sense. Why would it reflect through the YAG if the mirror is transparent to 532nm... Derp.

... I was wondering about that, imagining losses of the green in the crystal.

Well, there we go.

I would logically be able to keep the LAM as it would be doing the same job as it is currently, but the rest of the mirrors would have no use... I would need one other mirror that is partially transparent for the output... However at that point, dependant on cost, it makes sense to buy the 'LAM' mirror too, then I keep the whole Z-fold assembly whole in case I wish to go back to it again.


Ideally, for what I am interested in doing, I would like a nice and small spot size (as small as possible with said wavelength) and a nice, workable beam.
I hold interest in passing the beam through lenses and voice coils to distort the shape where needed. (an X and Y cylindrical aspheric lens)

The whole idea of buying that YAG unit was to save the money and time, then it's just two mirrors and a Q-Switch I already have. Though I dare say I'm oversimplifying it somewhat.


Hmm, Well, there is hardly the amount of data I'd imagine I should have... buuuutttt...
https://www.ebay.co.uk/itm/20mm-106...271366&hash=item569197dff9:g:YNgAAOxyMZ5Rmdy6

https://www.ebay.co.uk/itm/20mm-106...548387&hash=item569197d692:g:YNgAAOxyMZ5Rmdy6

And some mounts that look quite suitable?

https://www.aliexpress.com/item/Hig...408f-4199-a2db-9dff8f950100&priceBeautifyAB=3
 
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paul1598419

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Are you trying to modulate your beam? I could be mistaken, but it sounded that way to me. What pulse repetition rate are you planning?
 

paul1598419

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Yeah, that confused me along with passing the beam through "voice coils" as I don't think modulation would work in this case. He may have some other reason for this.
 
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Figured he was going for Q-switching, not modulation? :thinking:
Voice coils are for a separate thing.

A voice coil is basically a really simple linear motor. If you apply current in one direction, it applies a linear force in one direction, and if you apply current in the other, a linear force in the other.

So, if you pre-load it with some springs, you can vary the current to get an incredibly accurate position. (on the order of microns, possibly sub-micron with the right set up) You usually are looking at a 'small stroke' (5-40mm max) and you place a high resolution encoder on the side of it, depending on application.

http://www.mdpi.com/micromachines/m...y/html/images/micromachines-07-00207-g001.png

Above is a good explanation to what I have written.

The company I work for distributes and manufactures a wide range of motion control products in the UK, amongst them, voice coils.

I've been contemplating the use of them for dynamic on the fly focusing and defocusing in two axis. (Pretty common use)

That said, I was looking through the Solid-State Laser Engineering book, and I noticed a nice application would be moving a lens in a telescope cavity to assist with a quick, stable on time, helping with the issue of thermal lensing. (Page 248)

EDIT:
FYI, your diagram has a small error.
Also fixed diagram for other's reference.
 
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paul1598419

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I have Koechner's book too, but it must be a different edition. It is an excellent reference for all solid state laser projects. It will be interesting to see if your application for these voice coils used to set the focus position of lenses works well in practice.
 
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I have Koechner's book too, but it must be a different edition. It is an excellent reference for all solid state laser projects. It will be interesting to see if your application for these voice coils used to set the focus position of lenses works well in practice.
Indeed, it's the 6th Edition (Indian release, they had tip-exed that part out though, haha)

Look through the index for 'Telescopic Resonator' If it's actually covered at all.

Hmm, well, I look forward to trying it out, but first I need a strong ol' laser.
 




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