What Is It... thread for unidentified laser optic goodies

[krazer]

I will take a look through my stockpiles and see if I have an 80MHz q-switch driver good for 10W. $500 is way to much, that is almost the new cost for a suitable driver.

Also- I was never able to confirm that the q-switch in my avia was actually 80MHz, do you have access to a network analyzer to check the frequency of yours? It is possible that it is designed for 41MHz operation. If it is a 41MHz then you will probably need about 15-20W of RF power.

For the diode pumps, the normal 806nm fap should be fine. At the end of the day you should just sweep the temperature of the diode and see what gives best performance. It is also possible that the laser is designed to be pumped slightly away from 808nm, because this causes the pump to be absorbed over a longer length through the gain crystal which reduces the thermal lensing.

You probably won't get very far with coherent, because the first thing they will ask you for is your serial number which was on the outside of the laser. The manual wouldn't help you much anyway, the only useful information in it would have been the output specifications which you can easily measure once you have it running.

 

[Alaskan]

I can get access to a network analyzer and sweep the AOM, I used to own one, but sold it last year, one of these days I will get another one. I still don't know if this is UV or what, I've seen that crystal oven for sale on ebay in the past and the seller said it had a 20 mm long LBO in it for UV, the one he had probably came out of an Avia laser too, he thought so anyway.

Here's a video my wife was kind enough to make for me, a cut and banged up bent piece of surplus, but beautiful inside. The liquid cooling input and outputs damaged, fibers into the case cut, but otherwise appears undamaged. Will see how the crystals work later.

Coherent Avia Laser. UV or 532 nm ? Still trying to find which Avia model this is.

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[paul1598419]

It's a shame whoever salvaged this decided to cut the fiber optic cables. You won't be able to use any of them now. There must be a service manual for this thing. I don't believe that the only manual for this has nothing on the specifics of how it works or the schematics for the power supply and drivers. They seemed to have made too many of them to not have a comprehensive manual on it. I guess you will have to do what I have done when i get something new that doesn't work properly and search for a proper manual on it. I have always had good luck, though it has taken weeks at times to find the right one. Good luck, Chris.

 

[Alaskan]

I don't know I need a manual so much, but it would be nice. I've asked for the help of another laser professional to see what they think it is, UV or? In the mean time, it has more problems now, my wife was taking photo's and I think she hit a lens with the llid, she didn't hear it or notice it fall off:

This one:

Crest fallen:

I can probably fix it, the lens is undamaged, but this doesn't make things easier for me.

 

[diachi]

I don't know I need a manual so much, but it would be nice. I've asked for the help of another laser professional to see what they think it is, UV or? In the mean time, it has more problems now, my wife was taking photo's and I think she hit a lens with the llid, she didn't hear it or notice it fall off:

This one:



Crest fallen:



I can probably fix it, the lens is undamaged, but this doesn't make things easier for me.

That's unfortunate, hopefully not part of the cavity ... this laser won't be all that fun to align, seeing as none of the optics are really adjustable by normal definitions of the word.

 

[Alaskan]

She separated it from the electrical plating on the bottom, can go back but I am not sure if I can get it going again now, might have toasted the whole project for all I know yet. I won't ask such of her again, I trusted her, she has never been careless.. Lid goes back on and put away until I come home.

 

[paul1598419]

Wow, Chris. I'm sorry to hear this. It never occurred to me as you posted the photos, but every time you allow someone who has no knowledge of these assemblies, you take that chance. I'm sure you will be better off trying to do this yourself when you get back and can deal with it in person.

 

[Alaskan]

I thought don't touch anything inside was a good enough instruction, but she can't deal with that lid. My bad. Been married three years now, she is always very careful, mindful and responsible, that is what surprised me this time. No one is perfect, I might have done it myself.

Edit: Looking at this further, the piece is not a lens, but a mirror, and the way the foil ripped I can closely match it back together, this should not be a project killer. If it is just one optic, no problem, everything else is aligned. For all I know at this point, I might end up using the parts for something else anyway, but if it is a green DPSS, I will try to get it working.

 

[Alaskan]

Hey guys, can anyone help with this? what are some of the reasons to use an etalon? Are these just used to lock the wavelength of a YAG etc? I found an unusual 3 inch diameter 1064 nm etalon, any idea why one would be made that large?

 

[paul1598419]

Hey guys, can anyone help with this? what are some of the reasons to use an etalon? Are these just used to lock the wavelength of a YAG etc? I found an unusual 3 inch diameter 1064 nm etalon, any idea why one would be made that large?

Typically they are uses with laser media using external mirrors. It needn't be for pulsed operation. In holography they are used to increase the coherence length of the laser being used. I would think the size is related to the power, or rather energy in the case of a pulsed Nd:YAG, but may also be just for ease of alignment as the angle needs to be precise.