Just for the record, as you're reading this, keep in mind that I have laser safety goggles which cover all the wavelengths which this laser uses (1064nm, and 532nm, and 808nm to cover DPSS too), and I'm wearing them.

This laser was originally used to find fingerprints. It might be a model YQL-102, though thats from seeing something which looked right on a for sale website. The operator would wander around with it and a pair of goggles which filtered out the laser's light (532 nm), looking for the fingerprints floresceing in the laser's light (they floresse at a lower wavelength).

Then it got surplussed and eventually, I ended up with it. Hopefully I'll be able to make some holograms with it. It is allegedly capable of doing 15 millijoules per pulse.

Unfortunately, there's a problem. There is a loose optic somewhere. It rattles, when shaken just wrong, and when the optic shifts, the beam will fail to come out of the laser.

I've carefully poked all the optics in the YAG half of the laser. The all seem firmly attached. So, it must be in the frequency doubler half. I haven't been able to find it there yet, but I also haven't gotten up the courage to open the ominous gray cylinder. I was hoping that the components were a bit further apart, like in the YAG half.

The second problem is that the beam quality sucks. There is a big blob in the middle of the beam.

(That picture was taken by holding a pair of safety goggles in front of the thumb nailer. (I have two pairs of goggles.)).

2004.11.21

Time passes... I've taken the gray cylinder containing the frequency doubling crystal out. The crystal is, shall we say, eaten up... There are multiple burns on both sides of the crystal. They can just be seen in the image.

Another interesting event was that the lens I was using to inspect the beam in the picture above was also eaten. The laser incinerated the optical cement between the elements. It also put some interesting bite marks on my alen wrench.

Anyway, I moved the crystal off to one side so the beam goes through a less gnawed on part of the crystal.

So now, the current project is to redo the triggering circuitry to get single pulses out of it. That would be the breadboard sitting on top of the power supply...