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FrozenGate by Avery

Grow your own crystals!

I have also successfully frequency doubled with a home-grown KDP crystal with a titanium-sapphire pulsed laser (800mW).

Here is a blog I made about growing the crystal and getting the setup to work:
 
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Hmm. Fascinating work isle. However, you mention that 500mW is the least power necessary to see frequency doubling... how do you explain 5mW green lasers then? They are clearly powered by less than 200mW of 808nm light, which itself is probably dropped slightly by the fact that they are simply pumping vanadate?
 
Nice necropost, this was an interesting thread

Your 500mW 1064 likely didn't have enough juice to double to green since you don't have any kind of cavity mirrors or coatings on the crystal. The guy in the original page was using a pulsed Nd:YAG which probably had pulse powers in the KW range.
 
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I have also successfully frequency doubled with a home-grown KDP crystal with a titanium-sapphire pulsed laser (800mW).

Here is a blog I made about growing the crystal and getting the setup to work:

Very interesting...

btw... awesome dream journal...
It's too rare for people to have such in-depth dreams they are able to recall.
I *think* I remember most of my dreams (or at least I remember 3-4 each night)
 
I know this is a rather old thread, but it's really interesting to read.

Would you be able to double to other light colors as well, like put in 808 nm and get 404 nm out?

I think it's awesome you can grow your own DPSS laser components... :p
 
DPSS doesn't worked that way. :)
You need 1064nm wavelength to get 532nm green.
 
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Not all crystals work at all wavelengths. KTP, for example, isn't good below 500nm, so for doubling to 473nm you need something else. KTP would work well for doubling to green, yellow or red though. IIRC KDP shares many characteristics with KTP.
 
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Le Quack:
If you look at my webpage, you will notice that I doubled with a Ti-Sapph laser, which is a pulsed 795nm laser. Therefore, you should be able to grow your own KDP crystal and double it in a 808nm laser if you have a powerful enough laser.

Wolfman 29:

The best reference for you to look at is reference 9 in my full report.

Electro-optic, linear, and nonlinear
optical properties of KDP and its
isomorphs
D. Eimerl

This paper discusses the theoretical limits of frequency doubling with different types of KDP-like crystals. He shows the limit for type 1 frequency doubling for KDP at 1064nm to be an input power around 500mW (Figure 30). Different isomorphs have lower treshholds and type 2 frequency doubling also has lower threshholds.

If you read Wikipedia about Green Laser Pointers, you will find them say that the green laser pointers have a pump laser at 808nm between 100-300mW. The threshhold for this case and type 1 frequency doubling is 300mW and type 2 frequency doubling is 40mW. They could also be using KDP*, a purer form of KDP, which can also decrease that threshhold.

Hope that helps.
 
And a (for once :p) welcomed necro post at that...I would LOVE to try this. this only cost a bit... I have little money, but I think I could spare 10$. I am super busy this week though, so it won't happen until next week, if i decide to try it.


Now, to grow YAG is the next challenge :p
^not happening. Look it up, its not something we will ever be able to do without some expensive lab equipment!
 


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