Interesting Lab YAG laser (Disassembly)

[Mattronium]

At SELEM I bought this 1987 YAG laser from Alex. I don't think he tested it at all, so really nothing was known about it.

It has hose connectors for water cooling and indicates that it should not be run without water flowing. One place selling an almost identical laser lists it as 600mW @ 1320nm.

So naturally, after I powered it up and nothing happened, I opened up the laser. You can see in the first attached picture. I was surprised to see that the pumping source in an 500W halogen incandescent lamp. I didn't know you could pump a YAG this way. The water cooling only cools the YAG rod.

I believe that this laser is missing the HR mirror, though aside from that everything looks to be there (the reason it didn't run at first was because the interlock doesn't have the right pins shorted).

Just thought I'd share an interesting laser. I was quite surprised to find a halogen bulb in a laser.


EDIT: Upon further research it looks like it may be possible for me to use a aluminum FS mirror for the HR. As best as I can tell the OC is planer and from Sam's FAQ it seams it indicate that most lasers like this have a planer-planer mirror configuration. It looks like aluminum has a reflective of around 95% at 1.3 um range and since this is a CW laser I won't have to worry about ablating the mirror coating. I guess the question would be whether the laser could reach lasing threshold with the additional 5%+ losses?

 

[Alaskan]

Yow, I like the looks of that thing, very nice. I hope you get it running, if 1320 maybe make some 589 nm with it? If you can find the right crystal and the missing mirror.

 

[CurtisOliver]

Yes, quite a number of high power Nd:YAG's are pumped by flashlamp. Its nothing surprising at all. In fact, the first ever laser was a solid state (ruby) and was pumped by a flashlamp. You either side pump by flashlamps or side/end pump using 808 LD's.
I believe they are either krypton or xenon filled for YAG's.

 

[Mattronium]

Yes, quite a number of high power Nd:YAG's are pumped by flashlamp. Its nothing surprising at all. In fact, the first ever laser was a solid state (ruby) and was pumped by a flashlamp. You either side pump by flashlamps or side/end pump using 808 LD's.
I believe they are either krypton or xenon filled for YAG's.

That's the thing. It is NOT pump by either a flash lamp or a diode.

If you look at the last attached image you can see the pumping source. What looks to be a common incandescent halogen light bulb. Although I would say that this bulb has had quite a bit of use.

I didn't find very much information about Halogen pumped YAG lasers, though there are a few times that they are mentioned in Sam's FAQ:
https://www.repairfaq.org/sam/laserssl.htm#sslops
Another YAG that uses halogen lamp pumping: https://www.repairfaq.org/sam/laserpic/cviypics.htm

A quote from Sam's site "A very few commercial SS lasers have used common halogen lamps (and lots of cooling!) for pumping and even the Sun and chemical reactions which produce light have been used in the laboratory but these are extremely inefficient."

A post here: http://laserpointerforums.com/f44/technical-doubt-nd-yag-laser-pumped-halogen-55183.html

Yow, I like the looks of that thing, very nice. I hope you get it running, if 1320 maybe make some 589 nm with it? If you can find the right crystal and the missing mirror.

It sure would be nice to get it running simply from a historical perspective. Although I don't know how easy it will be to find the proper HR mirror for 1320nm. Assuming it is 1320nm at all! There really is almost no information on this that I can find. I highly doubt making 589nm would even be possible, even doubling it to 660nm might be impossible. Not that I would try it, just getting it working will be fine for me.

 

[CurtisOliver]

Well, it is still a flashlamp. Although it doesn't look too healthy. Does anyone know if the pump source is ok?
If it is indeed halogen then it is an odd one I admit.
Thanks for sharing with us.

 

[paul1598419]

That lamp looks like it has quite a bit of solarization. Seems to have had a hard life.

 

[Alaskan]

600 mw of CW sure doesn't impress, but if that's all you need, that's all you need. What is the rod diameter and length?

 

[Mattronium]

Without looking at it now, (packed it away for now), I would have to say it is about 2mm x 50mm. It is hard to say without opening up the cavity, which I probably should do sometime just to check the rod and make sure everything looks good.

 

[Alaskan]

That's about the size of a "SSY-1" rod which is Q-switched. I can understand why the CW power would be 600 mw, especially if pumped by a Halogen lamp. At that power level, you don't need an arc lamp, nor would you want to use one if a Halogen could be used to produce the power needed.

 

[Mattronium]

So I'm curious as to how much one of these lasers might be worth if working? (for considering how much $ it is worth to spend on repairs)
So my question to everybody is, What would you pay for a laser like this that is working? (assuming it is 1320nm and 600mW).

EDIT: So I opened the reflecting up and everything did indeed look good. Also, the YAG rod is actually closer to 35mm long.

 

[Seoul_lasers]

At SELEM I bought this 1987 YAG laser from Alex. I don't think he tested it at all, so really nothing was known about it.

It has hose connectors for water cooling and indicates that it should not be run without water flowing. One place selling an almost identical laser lists it as 600mW @ 1320nm.

So naturally, after I powered it up and nothing happened, I opened up the laser. You can see in the first attached picture. I was surprised to see that the pumping source in an 500W halogen incandescent lamp. I didn't know you could pump a YAG this way. The water cooling only cools the YAG rod.

I believe that this laser is missing the HR mirror, though aside from that everything looks to be there (the reason it didn't run at first was because the interlock doesn't have the right pins shorted).

Just thought I'd share an interesting laser. I was quite surprised to find a halogen bulb in a laser.


EDIT: Upon further research it looks like it may be possible for me to use a aluminum FS mirror for the HR. As best as I can tell the OC is planer and from Sam's FAQ it seams it indicate that most lasers like this have a planer-planer mirror configuration. It looks like aluminum has a reflective of around 95% at 1.3 um range and since this is a CW laser I won't have to worry about ablating the mirror coating. I guess the question would be whether the laser could reach lasing threshold with the additional 5%+ losses?

Actually, your eyes don't deceive you. The Yag 2 lasers from the 1980s are CW and do in fact use a special high temperature quartz lamp as the pumping source. We had 2 or 3 at Uvic that are now long gone.
So, yes that's indeed what it is.... btw, There are several retrofits that can be done to make this laser more efficient. :san: