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ArcticMyst Security by Avery

Expander lens alignment

Joined
Sep 19, 2010
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Could anyone offer me some tips on aligning an expander lens on a 50mW green pointer? I bought a cheepo laser on amazon.com to rip apart just to familiarize myself with laser anatomy. I took the expander lens(extremely tiny lens glued on right above the diode) off that was glued on with what appeared to be clear silicone rvt? I have it all back together but this little lens is giving me all kinds of problems trying to get it to align properly. I noticed when I took it apart that the lens was nowhere close to being centered exactly.
 





Joined
Oct 26, 2007
Messages
5,438
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Here's a diagram of the DPSS green.

The diode in the green is an infrared laser, pumping out lots of dangerous, invisible infrared laser light that your eyes don't even realize is "bright." It's extremely dangerous, and you should have goggles which block infrared before you even attempt to realign the lens.

However, I don't think you're realigning the lens in front of the diode, rather you're aligning the collimation lens in the front. There's still quite a bit of IR there, but not to the extent of inside the DPSS. Centering it? Well, first make sure it's as clean as possible, and then you'll probably need some tweezers and some trial and error to get it just right. Then use some silicon glue to keep it in place. Try to keep it as flat as possible too.
 
Joined
Sep 19, 2010
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After looking at the diagram you posted it is def the expander lens that I'm trying to get right. Directly under the lens I can see the little square thing that looks like a crystal or something. The lens is about the diameter of a BB. It is a tiny little lens with what looks like 2 concave surfaces inside the lens.
 
Joined
Oct 26, 2007
Messages
5,438
Points
83
Yeah, that's not going to be fun to align. I've got an old opened module and getting that centered will probably require you to attach the lens to the center of some other round plug that you can lower into the chamber to get it centered, and then glue it all up. If you can pop it out, maybe you can unscrew the outer casing for more control.

I'd actually suggest you just buy a new module, and leave this one for experimentation or something else. They're not too expensive, especially if you buy them from O-like or some other Chinese parts company. Sometimes the host is the best part of the lasers you can buy and you can reuse it for some other purpose, or a higher powered module.
 




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