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2%Nd:YVO4 Laser crystal

H

High_Octane

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o_DEATH_ANG3L_o

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I would assume with correct alignment you might get 532 green. But don't quote me on that though. Maybe someone else here would have better insight.
 
L

likewhat

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You wont be getting anything to the blue of 808 without a frequency doubling mechanism of some kind.

The crystal will absorb the 808 light and become excited, then it will flourese at several different colors to the red of 808. if you put mirrors on both sides of it to make a cavity you could make a 1064 nm laser, if you stuck a frequency doubling crystal in it at the right angle you might get some green out too.
 

philguy

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Well, it appears it is already coated so that it would work as a 1064-generator. Which would hypothetically mean, all you'd need is "just a KTP"*, and you're all set for green lasing. Still, as one of andy's posting showed me recently, I have no idea about the complexities of green lasers, so I wouldn't give a penny about my own talking.

But to quote him here, "even if you fail, it is a great lerning experience".

Although, the seller's homepage sure looks interesting...(www.snochina.com for all those too lazy to get it), as they have a waterproof greenie (50-200mW) and a blue pointer (5-20mW), which appears to either be a scam, or a cool novelty, but sure no prices on the website (which kinda sucks). Also I'm afraid that with the blue one, the beam comes out the wrong end.





* "just a green KTP" = and a huge amount of patience, a high frustration theshold, and tons of luck to maybe get a mediocre laser
 
H

High_Octane

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Is there anyone that makes a module to hold and adjust 2 crystals?

How many crystals are in this pic? or does the KTP just look like this?


I would like to get the Nd:YVO4 and the KTiOPO3 for my 1000mw 808nm laser diode. However if there is no easy way to mount and adjust the crystals, it may be pointless.

One last question...
Will a TO-5 diode fit into a 9mm or 5.6mm diameter housing? If not who sells such a housing?

Thanks
 

Benm

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A TO-5 case will fit into a 9mm hole, but not snugly. It's a transistor casing originally, with quite some tolerance to its actual diameter - 7.5 to 8.5 mm or so.

Would be easy enough to fit in with thermally conductive glue, but getting it out is another story ;)
 
H

High_Octane

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Benm said:
A TO-5 case will fit into a 9mm hole, but not snugly. It's a transistor casing originally, with quite some tolerance to its actual diameter - 7.5 to 8.5 mm or so.

Would be easy enough to fit in with thermally conductive glue, but getting it out is another story ;)
Thanks Benm, I feel better knowing that my LD housing will in fact work with this diode.
Even if I do have to modify it a bit, We shall see how much when it arrives.
 
H

High_Octane

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Well I modified my AixiZ module to fit the LD "the LD was much larger". Snatched my Night Vision camera from outside, applied 2.2 volts and NOTHING??? The LD isn't working!!!!
I put an LED in the circuit, and when I connect a feed wire to the LD the LED goes out almost like the LD is shorted rather than pulling a load?

Is it possible the LD has a short?
 
L

likewhat

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You could be hooking it up wrong somehow? Or since it is jammed into a hole that it is not designed to fit into I could imagine a scenario where the pins where touching the housing somehow.

Do you have DVOM that you can measure it with to see if it is broken or not. You should be able to determine which is the right way to hook it up and also if it is somehow shorted.
 
H

High_Octane

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likewhat said:
You could be hooking it up wrong somehow? Or since it is jammed into a hole that it is not designed to fit into I could imagine a scenario where the pins where touching the housing somehow.

Do you have DVOM that you can measure it with to see if it is broken or not. You should be able to determine which is the right way to hook it up and also if it is somehow shorted.
I drilled out the AixiZ module, and it fits but not real tight, The pins on the diode are covered as to not short.
The polarity is as follows
.---> Ground
Positive<--------- . . ------> Nothing connected
When checking the positive and negative pins on the diode with my Meter set to Diode it reads .016 no matter which way I connect the polarity.

when checking the pins using Ohms "20k setting" it reads 0.16

So is it fried? I hope not it cost me about $75.00 :'(
 
L

likewhat

Guest
It sounds like it is shorted. A diode should only read in one direction, because in the other direction current does not flow so it would appear open. If you read the same in both directions then it is broken somehow. As a sanity check test another one and see if it acts the same or not.

When powering on laser diodes it is important to slowly turn on the current, transients is usually what kills them. That is probably why that one guy from here always talks about putting a capacitor across the diode, that way it will protect it from fast transients.
 
H

High_Octane

Guest
I was afraid you where going to say that. I only have the one, at $75.00 each I can't afford any more.
I do have a capacitor in my Power Supply circuit. I was hoping that I was under powering it, as the specs show a much higher amperage than the 250ma=/- that my PS is putting out.

Thanks for your help.
 




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