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ArcticMyst Security by Avery
beam visibility with expander ?
- Thread starter BKarim
- Start date
what a beam expander does, it decreases the divergence of the laser, which means that it will hold a "beam" for a longer distance without it opening up as much. but it also expands the diameter of the beam, so you have a much less concentration of light on a wider beam. it doesn't add power to the laser, so the beam will actually look dimmer than the original one.
and as for "does the line look longer?"
--when i shine my 532 100mW laser into the sky (at night lol) the beam goes as far as i can see, this is of course me viewing it directly from behind. but about 300 feet away from it, when its pointing straight up, its hard to see a beam at all. I live in AZ desert so there is rarely any fog here so that will also affect the visibility of the beam. i did however, take my laser when i went camping in the White mountains here in Arizona and i could clearly see it from >300 feet while my friend was pointing it directly upwards. but there was no moon at all that night and my guess slight fog was in the air.
so if you have a beam expander and a powerful enough laser, preferably green because you get the most visibility per power then you should be able to see a "longer" beam from far away
and as for "does the line look longer?"
--when i shine my 532 100mW laser into the sky (at night lol) the beam goes as far as i can see, this is of course me viewing it directly from behind. but about 300 feet away from it, when its pointing straight up, its hard to see a beam at all. I live in AZ desert so there is rarely any fog here so that will also affect the visibility of the beam. i did however, take my laser when i went camping in the White mountains here in Arizona and i could clearly see it from >300 feet while my friend was pointing it directly upwards. but there was no moon at all that night and my guess slight fog was in the air.
so if you have a beam expander and a powerful enough laser, preferably green because you get the most visibility per power then you should be able to see a "longer" beam from far away
- Joined
- Sep 16, 2007
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It will be visible much farther (depending on expansion) but the apparent "length" of the beam will remain much the same. Unless your laser had terrible divergence to begin with, the beam will not be too noticeably "thinner" when pointing into the night sky. The spot will be visible at greater distances, obviously.
Up close, as you stated, the beam will not be as intense due to the lower power density at aperture.
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