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FrozenGate by Avery

Why can't 980nm be frequency-doubled?

S

Sta

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Jan 27, 2014
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Excuse my idiocy!

I'm just wondering why 980nm isn't easily frequency doubled into 490nm like 1064nm is into 532nm. Is there not a proper crystal to do it?
 





If I remember correctly, it's because the efficiency of the doubling crystal (KTP) drops to uselessness after 500nm. I read that somewhere around here.
 
Sta said:
Excuse my idiocy!

I'm just wondering why 980nm isn't easily frequency doubled into 490nm like 1064nm is into 532nm. Is there not a proper crystal to do it?
Click to expand...

It can but the crystals and coatings required don't come cheep.

My protera produces 488nm by the direct inner cavity doubling of 976nm through a KNBO3 crystal
KNBO3 can also work at doubling 980 to 490 In fact IIRC a member here on the forum has done it. I'll give him a pm and see if he would like to chime in.
 
Last edited by a moderator:
It can be done with BiBO, but direct SHG
from a diode is problematic. There only a
few modules around that do it. There are
wavelengths close to that that are more
commonly done using vanadate. LBO and BBO
will also work, but they must be inside a
sealed chamber because they absorb
atmospheric moisture.
 
You can do it, but you don't see them around because its not producing any wavelength that anybody wants. Plus as I understand it you need to perform some diode correction.

It's actually not as bad as you'd think. I can probably get a functional module for ~500-700 bucks.
 
ZRaffleticket said:
You can do it, but you don't see them around because its not producing any wavelength that anybody wants. Plus as I understand it you need to perform some diode correction.

It's actually not as bad as you'd think. I can probably get a functional module for ~500-700 bucks.
Click to expand...

For not a whole lot more than that, you can get a 490nm single mode diode.
 
rhd said:
For not a whole lot more than that, you can get a 490nm single mode diode.
Click to expand...

uh...where? Unless you are referring to the 488 diodes, which are several thousand $, not several hundred.
 
crazyspaz said:
uh...where? Unless you are referring to the 488 diodes, which are several thousand $, not several hundred.
Click to expand...

I am.

And they're not "several thousand", they're a little bit over one thousand.

And that's "not a whole lot more" than $700.

;)
 
rhd said:
I am.

And they're not "several thousand", they're a little bit over one thousand.

And that's "not a whole lot more" than $700.

;)
Click to expand...

Eh? I can only assume you are referring to the Osram diodes, but those aren't for sale anywhere.
 
Now i wasn't aware of this diode development. Ah well, I can't afford it either way. Maybe when the price goes down. A lot. College is expensive :(
 
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