Experiment and tell us.
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ArcticMyst Security by Avery
Beam Expanders ---
- Thread starter Hemlock_Mike
- Start date
Experiment and tell us.
- Joined
- Feb 2, 2012
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doesnt seem to work with a air rifle sight 
may need a more powerful laser!! :eg:
may need a more powerful laser!! :eg:If you have possibility to remove focusing lens from your laser you should deffinitely do this. DPSS module output right after expanding lens has at least 20-25% higher power than after focusing lens! If you use 50-70mm focal length high quality lens with AR coatings it will be 15-25% better than original lens and over 30-40% better than cheap telescope which you attached to the focusing lens exit. You should place it right after expanding lens in a correct distance. What are the issues with stock lense?
1. Non coated glass transmits 90% of power, AR-coated 99%
2. Crappy 5mm diameter 20mm focal length lens heavily obstructs beam of the laser, and creating artifacts
3. With beam expander attached after focusing lens you have 3 optical elements after expanding lens. With stock lens removed and high quality lens installed you have ONE high efficiency optical element acting as beam expander.
4. This setup gives excellent beam specs, higher power and no spherical aberrations/beam artifacts
5. When focusing laser beam at close distance for burning, the power difference increases becouse the further the focusing lens is moving away from the expanding lens, the higher the obstruction becomes. Bigger HQ lens has no obstruction.
When I buy that lens and bring it home I'll make some photos for you.
I don't have my own LPM but I measured power of my laser at the physics college, it's a pity that I haven't got a camera with me. It loses over 120mW at the crappy factory installed focusing lens!
1. Non coated glass transmits 90% of power, AR-coated 99%
2. Crappy 5mm diameter 20mm focal length lens heavily obstructs beam of the laser, and creating artifacts
3. With beam expander attached after focusing lens you have 3 optical elements after expanding lens. With stock lens removed and high quality lens installed you have ONE high efficiency optical element acting as beam expander.
4. This setup gives excellent beam specs, higher power and no spherical aberrations/beam artifacts
5. When focusing laser beam at close distance for burning, the power difference increases becouse the further the focusing lens is moving away from the expanding lens, the higher the obstruction becomes. Bigger HQ lens has no obstruction.
When I buy that lens and bring it home I'll make some photos for you.
I don't have my own LPM but I measured power of my laser at the physics college, it's a pity that I haven't got a camera with me. It loses over 120mW at the crappy factory installed focusing lens!
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- Joined
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I would enjoy seeing this! :thanks:
lol! i have an old 60mm refractor (about 3 ft long LOL) i connected my 400mw greenie to, and i send a fairly bright 3 inch diameter beam into the sky
i think my neighbors are afraid of me...
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laserpointersafety.com
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Blade, why the love for laserpointersafety? They seem like nazis who would get rid of anything that allows most of us on the forum to have lasers or build them as a hobby.
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