Need help with crystal alignment on a focalprice greenie

I bought this from focalprice and it was fine when I got it but after a while I noticed that the beam would fade when held a certain way. It has progressed to a point where it requires a good shake to get it green.

I took it apart to see if I could find a way to secure the crystal. The innards look different from the other dropped greenie in the other post.

I was wondering if anyone could give me an idea on how to fix this laser.

Or would it be better just to use it as a host for something else?

Thanks!

Have you checked to see if the LD is secure? If the retaining nut for the diode is loose it can allow it to rotate or come away from its position. If the threads were not glued, every time you open the battery cap, it could have turned it slightly. Another thing may be that the crystal has a burn on it, if this happened, everytime you shake or hit it, it may briefly find a good spot and generte the green.


Try a little tension on the board and rotate it. If it moves, than this is most likely the issue. It looks as if the optics are in place...

Also be carefull with the IR, there appears to be no filter.

It seems the diode is pressure fit and glued in place even the driver board is glued to the brass tube there is no play at all. I tried wigglng just the exposed optics in the 3rd picture and it was not moving either.

I have a laser that looks like that from FP. Is yours the "50mW" (bullshit) model? There's one visible difference and that's that spring that seems to be over the focussing lens on the diode, mine doesn't have. Did yours also not come with a lanyard? ...Lying bastards...

Mine had a similar problem, but i would twist the head part to make it work or not work accordingly. I don't think the problem is with the crystal alignment, i think it's a poor electrical connection or something... not sure. I fixed it by stretching the spring on the diode and stuffing some aluminium foil into the positive contact on the tailcap. Good luck!

It's definitely an alignment issue since I can see the red glow of the IR diode when it's not lighting green. The spring in front is there to ensure contact with the body of the host for the electrical connection. In my laser there is a gap between the front cap and lens assembly so the spring is needed to bridge the gap.

Ohhh...kay then. Hmm...

Well, i'm far from an expert, but to me it doesn't look like there's a problem if everything's still stuck down, and my laser had a problem similar to what you described that was due to the loose connection. You could also try making the connection better between the button on the host and the button on the driver. That was erratic for me.

On the other hand, when my crystal assembly came loose I took it out to try out the pump diode (experimentally) and i could see a slight red glow too. It gave me a headache (although i think that was placebo). I then tried aligning it by eye and sticking it back to the residue glue on the surface of the pump diode and the crystal assembly and i got almost as much green back. You could try pulling the assembly off and then sticking it back on but my feeling is it would make it better rather than worse.

If you do take that course of action, don't use superglue to stick them back together. I tried, now nothing's working right.

Be careful with that dim red glow.. that's at least 200mW of IR laser radiation. If it entered your eye and gave you a headache, it could have easily done retinal damage.

ElektroFreak said:

Be careful with that dim red glow.. that's at least 200mW of IR laser radiation. If it entered your eye and gave you a headache, it could have easily done retinal damage.

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This. And I would also use a camera as your "eyes" so you can see the ir.

wolfhunter9154 said:

This. And I would also use a camera as your "eyes" so you can see the ir.

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I second this. (+1)