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ArcticMyst Security by Avery

Advice. Beam which is visable in a ROOM...

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Nov 20, 2009
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Hi all, could anyone give me advice on which laser I should buy if I want to be able to see the actual green beam inside my house...possibly with a light on? Not just visable 'in the dark outside pointing at stars'.

Say for instance, this laser - Newest 5mW 5 mW 532nm Green Beam Laser Pointer Pen on eBay (end time 11-Dec-09 13:38:41 GMT)

What's the odds of that laser (5 mW) being visable in a house. Hell, you're the experts, is that laser even any good in the first place, like power and distance? I know nothing about lasers, I used to have a red one years ago but beam was not visable. I now want a visable beam green laser but fear it will only barely show up when it's complete dark and no, I do not want to spend like $100 lol More like $20 haha.

EDIT: Also, is there such a laser where it is a SOLID beam and not a scattered beam like the rotating banner ad at the top of this page suggests?
 
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Mar 18, 2009
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With a green (532Nm) 100 mw laser, im shure you will be able to see it just fine.
I have a few E-bay laser's id be more then happy to dig out of the trash can... Op's !
 
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You mean you have lasers you're putting on eBay? You see, I don't really want one as powerful as 100mW as you have to wear safety goggles and stuff. A 1-5mW would probably be sufficient but that is why I'm trying to find out just how visable the beam really is as I have seen some good ones and some aweful ones.
 
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No, i doint sell lasers on E-bay, i did buy a few there.
At night i use a 20 mw for star pointing. 80mw work's good in the daytime.
O-like sell's both for a price that is nice.
But if you use over a 5-10mw laser indoors it is best to invest
in a pair of safety glasses.
 
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HIMNL9

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Basically, the visibility of the laser beam does not depend only from the power, but mainly from the particles suspended in the air and ofcourse, how much light there's around (in a clean room or in the void, you cannot see also a 100W beam, where instead in a foggy night you can see an 1mW beam very well :p)

A 5mW unit can be seen in a smoky / foggy ambient, but not in a clean one, especially at daylight ..... a 100mW unit can be seen also in a "clear" night (cause the air around you is really never "clean", if you're not in a white chamber), and can be seen also in a normal light room, usually also without smoke (not at full sun, anyway).

And, btw, both a 5mW and a 100mW units requires brain, more than goggles ;) ..... i mean, not just the fact that with a 100mW is better to wear goggles, also a 5mW unit can be dangerous, if misused or in the hands of peoples that don't know how to manage a laser (i wear them also with 5mW units, if i have to work aligning mirrors and prisms, with my head and eyes almost in the same line of the lasers and any possible reflections ..... or playing with prisms and "swarowsky" crystals :p ..... and instead, when i'm playing in safety conditions and with no reflecting surfaces around, don't use them also with high power units)
 
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I'm not trolling, I'm asking a simple question. A own a forum larger than this one so I'm not the sort of person who trolls. I'm just trying to get a clearer picture on how these things work. Also, I wasn't asking you if you were selling one, I was merely asking if you had any experience with a 1-5 one.

Thank you for your reply HIMNL9. I guess it's still impossible to create a laser beam which is visable in the sunlight no matter what the air is like. Maybe in the future.
 

STI24

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I bought a 5mw laser from eBay and the beam is visable in a dimly lit room or if the room is smoky with a light on you can faintly see the beam as well, and of course its clearly visable at night. I bought this one, 5mW 532nm Laser Pointer Pen
 
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The particles in the air is most definitely the primary factor. Sure, human eyes are more sensitive to green than red, but light in open air has never been something you can see. Light needs the larger particles in the air to be reflected enough back to a persons' eyes. Fog machines are great for this reason.

5,000 watts of 532nm laser light is still invisible in a vacuum.

I hope this helps.
 
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I mean that if you have even large amounts of light, with nothing for the beam to reflect from, it will still be invisible. Just another way to look at it is all..
 
D

Deleted member 8382

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if you own a forum larger than this one I'm sure you know what a FAQ is and what they are for. Go and read them and you wouldn't be making us loose our time with such a questions. I think they are answered more than 10 times if you read all the faqs.
 
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if you own a forum larger than this one I'm sure you know what a FAQ is and what they are for. Go and read them and you wouldn't be making us loose our time with such a questions. I think they are answered more than 10 times if you read all the faqs.

Then again, that's quite true..
 




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