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Anyone here collecting parts for, or working on a DPSS project?

Alaskan

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I'm wanting to compare notes with other hobbyists who are interested in DPSS technology, is anyone here planning, or working on a DPSS project? If you are, even if this thread is found much later, please add to it, I want to compare notes.

Chris
 



RedCowboy

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Been interested in diode pumped Nd:YAG but haven't built anything yet.
 

Alaskan

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Well, as I've been told before by experienced laser professionals in the past, it ain't as simple as some odd crystal found on ebay and shooting 1064 nm into it. I can hardly get any green at all using my 1064 nm 1.5 watt output pointer, without using the correct lens to properly focus into the material, the power density isn't high enough and that is only part of the problem.

I wish there was a YT video on SHG which gives a lot of practical optical advice for SHG, maybe there is, I will keep looking. The best I've found so far is one produced by Tech Ingredience. That said, there are lots of videos to be found about DPSS, good stuff, but I haven't found my DPSS SHG guru to follow yet.
 
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RedCowboy

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My 1st thought is maybe try pumping a smaller crystal and is your crystal mirrored on the ends, HR and OC mirrors ........well are you side pumping or end pumping.....I have taken apart the dpss 532nm lasers and put them back together and the alignment matters, I move the crystal set in the little fixture around until I get output, it can be picky and I suspect parts need to be within a range.

You should get some output even without mirrors shouldn't you ?

I'm sure there's plenty to learn and plenty to burn up while learning.

Have you read this yet ? I expect you have but here it is again. https://www.repairfaq.org/sam/lasercds.htm
 
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Gianakakis

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My 1st thought is maybe try pumping a smaller crystal and is your crystal mirrored on the ends, HR and OC mirrors ........well are you side pumping or end pumping.....I have taken apart the dpss 532nm lasers and put them back together and the alignment matters, I move the crystal set in the little fixture around until I get output, it can be picky and I suspect parts need to be within a range.

You should get some output even without mirrors shouldn't you ?

I'm sure there's plenty to learn and plenty to burn up while learning.

Have you read this yet ? I expect you have but here it is again. https://www.repairfaq.org/sam/lasercds.htm
Yea you will get output without the mirrors but they are pretty much needed for good results @Alaskan I suggest taking apart an eBay green pointer, getting the monolithic crystalline assembly out that contains the Nd:YaG and KTP pre-coated and then getting an 808nm diode with a g2 at least 300mw in power and focusing that into the crystal. Also as Red cowboy mentioned alignment is critical in getting good results, so If you don't get good results fiddle around with the rotation of the monolithic crystalline assembly.
 

Alaskan

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Thanks, that's it then, put the crystal in a cavity with mirrors. If I do not rotate the crystal to the correct angle I get nothing at all, so I have been rotating.
 

Alaskan

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Looking for 532 nm SHG cavities with mirrors, I have found some from YAG lasers which are separate from the YAG, but $$$.
 

ultimatekaiser

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Fun but expensive project. And yes they would be very expensive because they have to be absolutely rigid and precise.

You should get some output even without mirrors shouldn't you?
It depends on the gain of the medium involved. This is referred to as single pass gain, And generally the answer to it is no. But there are some instances where you definitely can get at least a little bit.

I do recognize that a YouTube video on this would be very helpful but unfortunately that involves so many topics that you would never be able to cover them all in a single video. There’s a lot of very complex physics involved. :)

If you’re making a Fabry Perot linear cavity, that would be fairly easy to start with, and aligning it would be not be too dissimilar to a helium neon laser with some extra components and rules.
 
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