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ArcticMyst Security by Avery

What colour at Class I will let me see the whole beam?

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Oct 29, 2010
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Thinking it was just "Hollywood" at first, I've found that lasers which can be seen by the naked eye are actually real. However, I am after a Class I version, something completely safe yet visible. Oh, and in red.

Nay you say, it cannot be done. This is disappointing, directed to green instead. But I read that green requires safety goggles, even at low power, is there a Class I green laser?

Also, what of the other varieties like violet and blue, do they come in a combination of low power Class I and visible to the naked eye… there must be a way.


Thanks.
 





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Aug 27, 2010
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Getting a visible red beam even in the dangerously high power levels is very difficult, red light is both significantly less sensitive in our visual spectrum and far less effected by Rayleigh Scattering which helps make the lower wavelengths much more visible.

A truly <5mW green pointer (ie. NOT the one listed as 5mW on eBay or Chinese sites) is very visible in low light and almost entirely eye safe, a quick reflection or glance wont really harm much as long as you don't stare into it. I suggest one from AtlasNova (abeland1 on ebay) with "APC". These will not exceed 5mW and are very safe for recreational use without needing glasses.

Of course you should always try to use them responsibly, never point them at someone intentionally, don't look directly into them. Always treat a laser of any power as if it were a loaded gun and you'll build proper safe handling habits for any power level.
 
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Oct 29, 2010
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Thanks, but what of the other colours? i take it they are just too powerful? With a <5mW laser what happens if you look at it for say two seconds?

What about the ones used in clubs? They reflect in all directions, how are they safe? I really would like a red one you know, is there no way to get one of strength but filtered safe?

Thanks.
 
Joined
Sep 20, 2008
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You can get a red <5mW laser at the Dollar Store...
The beam will be visible if you have particulate in the
air...
A green <5mW laser (the same power) will look brighter
to you... since 532nm is close to the most sensitive
wavelength the human eye detects...
One problem is that you will never know or should you
trust the output of a laser without actually testing with
an LPM...

I've recieved 5mW lasers that were tested at 50mW...
10 times more that was stated by the seller...
At a true output of 50mW you will need to use Laser Saftey
Goggles...

Jerry
 
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So is there such a thing as a Class I green laser? Totally safe, yet visible in normal air? You say <5mW, but I read that visible lasers start at Class II and they're dangerous. So its Class II or nothing then? If thats the case then can I go the red route?

I found one on Amazon UK that says its a 1mW but pretends to a 5mW and that it has a visible beam, what are your thoughts: http://www.amazon.co.uk/Pointer-Bri...8C/ref=sr_1_15?ie=UTF8&qid=1288322227&sr=8-15

Oh and as I'm in the UK were only allowed up to Class II, so I read on Wikipedia, but I see higher for sale on Amazon?!

Thanks.
 
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horhay

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Apr 8, 2010
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anything with a decently visible beam will be dangerous to your eyes without safety goggles, unless theres smoke/fog/etc to make it pop. green is the best for visibility vs. safety though. still a class I-IIIa green will barely be visible in darkness without particulates... there is no "magic" technology to make it brighter without causing damage.

i believe that eye damage occurs at 25mW/second. so, a 5mW laser would damage your eyes in 5 seconds. the blink reflex is about 1/10th of a second, so you've got that on your side.
 
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Nov 17, 2009
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5mW is Class IIIa. 1mW is Class II. Class II is really, honestly, minimally dangerous.

Atlasnova Green Laser Pointer with Feedback

Even at 5mW (Class IIIa), permanent eye damage is unlikely. You'd probably be fine with a 1mW Class II green from Atlasnova. I actually have one, it's very well built.
 
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Oct 23, 2009
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Even a red laser you can buy at a grocery store checkout line can be dangerous if you have preexisting eye conditions. There is no such thing as a "perfectly safe" laser. a 1 mW laser can still harm the retina of someone with retinopathy. (most common cause of which is diabetes) There are other eye conditions that could cause extra vulnerability. but they are not common. A former co-worker of mine lost a piece of vision a long time ago to a normal grocery store laser pointer. He is diabetic.

So you are aware, 5 mW red and 5 mW green are identical in how bad they are for your eyesight. Your retina doesn't care about the color. At least as far as damage goes anyways. Green will ALWAYS look brighter then red at the same power levels. So 1mW green looks much MUCH brighter then 1 mW red. However both have identical eye risks. Technically a 1 mW red and 1 mW green are identical in brightness and that's what matters for damage. However the way our vision works, is it peaks at green. Also as green light scatters better, you can have a more visible beam. A 5mW green is reasonably safe, and at night you can usually see the beam if you are standing behind it.

You won't be seeing the beam of ANY portable laser in broad daylight. Not even with a 1.5 watt class IV laser. At night time, the higher the mW the easier it is to see the beam and the farther off to the side you can be and still clearly see it. However if you get one of the 5mW APC greens that Aryntha linked to above, you will get the best beam while still being relatively safe. Still treat it like a loaded gun. After all, you don't know always if someone around you might have such an eye condition. It only takes a momentary lapse for someone to get hurt.
 
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My application is to embed it into a counter in a shop, the counter allows staff to pass from staff area and onto the shop floor but the idea of a barrier like a piece of rope or a gate seemed too cumbersome. So I thought that a red laser beaming across the two counters (at about hit height, of around half a metre) would be a great idea as its clearly there to stop people while allowing those authorised to just walk through. I would also need it to be non corrosive so that standing in the way of the beam even for say two minutes would not burn anything.

What do you think about that; health implications, type of laser... The lighting conditions would be moody but clear and of course indoors.

Thanks.
 
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Laser beams are good for many things. Acting as a barrier is simply not one of them.

Get a sign:

89923VS.gif
 
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Right well lets not get into replies like that, I'm still hunting for a solution. What about other laser types like gas ones?
 
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Feb 5, 2008
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There is a line between bada$$ and totally stupid. Thin one, but there is one.

"Only employees are allowed to pass through laser" How does that sound ? I'd say, the bad side of that line.

Simply get a sign. People tend to mind their own business anyway. If somebody really wants past that point, laser won't stop then anyhow.
 
Joined
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Now that we know what you want to do... a Laser of sufficient
power to be clearly seen in the daylight at a level above ground
in mid air would require you to enlarge the Beam Diameter to
around 1"-2" with optics and you will need a high powered class
IV Laser to accomplish that... or come close to it...

You could use Line Generating Optics to shine a RED Laser beam
at the Ground across the opening and have the Laser Flash to
attract attention... with a sign on the ground neat the Laser Line
stating.... EMPLOYEES ONLY

This forums spent.

BTW.... what did you mean by that....:thinking:


Jerry
 
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Thanks but I don't want to use a Class IV laser or optics as this increases risk. I'm looking for a line and I think the Atlasnova Green Laser Pointer with Feedback will get me that. The conditions will be indoors, ground floor, but it does not matter as lighting conditions are mostly artificial when far enough inside the shop.

I thought about making the laser thicker, but I woul be better with say three bars. The visibility thing I think now is licked, perhaps its just an issue now of whether the lasers would burn people after a certain amount of exposure - something I think a 5mW Laser will not do.

*I meant my time here was done, with comments like I was getting it was time for the off*
 
Joined
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Messages
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Thanks but I don't want to use a Class IV laser or optics as this increases risk. I'm looking for a line and I think the Atlasnova Green Laser Pointer with Feedback will get me that. The conditions will be indoors, ground floor, but it does not matter as lighting conditions are mostly artificial when far enough inside the shop.

I thought about making the laser thicker, but I woul be better with say three bars. The visibility thing I think now is licked, perhaps its just an issue now of whether the lasers would burn people after a certain amount of exposure - something I think a 5mW Laser will not do.

*I meant my time here was done, with comments like I was getting it was time for the off*
You do not understand. There is no laser that will fit your decription and needs.

You obviously never had a laser before.

Please go ahead and buy the forementioned 5mW green laser pointer. Then let us know how the magical visible laser ray appears in your store.

Or do we save you the trouble and say it's not going to be visible unless it's pitch black darkness and you know exactly where the beam is at?
 




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