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ArcticMyst Security by Avery

Free 405 nm pointer from Wish

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Hi!

I got a free 405 nm "<5mw" laser pointer from Wish (chinese store thing) which I suspect is a lot more than 5mw. Are there anyway to guestimate the ballpark figure on how powerful this thing is?

In a dark room, the beam is a little more visible than my 532nm 10mw laser. If I focus the beam through a magnifying glass, I can make burn marks in wood, but not light a match. It seems to have slightly more burning power than the 532nm 10 mw without IR filter through the same magnifying glass.

It uses 2x AAA batteries.

Would this be enough to guestimate the power of this laser? At least some sort of ballpark figure?
 





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Not really. Though many of these come in at 40 mW to as much as 80 mW for ones that are a larger than a pen. If you had a link to the laser, I could give you better information.
 
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Oh, those are very low in power. Maybe 20 mW to 30 mW maximum. I've never had one that really burned anything. I never bothered to put a focusing lens on any of them as others here have done. Didn't seem to be worth the time or effort.
 
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Yeah, I don't expect it to be high power or anything, and I didn't really spend time with a specific focusing lens, I simply pointed the beam through a cheap magnifying glass and noticed it was able to create burn marks in wood. So I'll assume 30 mw is a "safe" ballpark figure for this. It was free, so I don't expect much from it. The beam isn't really good, spreads quite a bit, like from 1/4" to 1" on a distance of 6 feet. It's just a bit crazy that they advertise it as a "safe" <5mw laser, when it's a bit stronger than that and could pose a risk. I can imagine laser-ignorant people buying this and treating it as a toy thinking it's too low power to cause any injury......
 

GSS

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My one the same pointer puts out 77mw that Pman made focusable. Which I don't think is out of the norm? Iv'e seen a little more from them.
It will light black tip matches when focused tight.
I'm not sure if the lenses are set up like the 532's were you can break the glue on the front set focus lens. If you can make it focusable they are alot of fun:)
Pman did put out a how to focus thread a few years back..
 
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I metered my little 405nm pen and it wasn't near 77 mW. My 301 and 303 are in that range. Nice little burner you got there, Peter.
 
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Well, removed the cap on it and it's actually focusable. The focusing ring isn't even glued in, was just hidden by the front cap. It was badly focused from factory, but has a much better beam now. Still dont think it can light matches, but makes burn marks in wood
 
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Yeah, those single mode 405nm diodes can be focused to a very small spot. That makes the energy density of the beam quite high, regardless of the power.
 
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I have to say it's a pretty good deal for free (plus shipping, but was only $3-4). But if you want a quality laser you should of course look for something better. :)
 

GSS

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I metered my little 405nm pen and it wasn't near 77 mW. My 301 and 303 are in that range. Nice little burner you got there, Peter.
I didn't see this till now..I'm sure the other "Pete":beer: sent me a better output one.
Still bring it out on occasion as believe it or not it was my first match burner:) I think?
Skauber, if you follow Pmans way of focusing them with the front cap or anyway you might do, it's a whole lot of fun.
What my first 532 did to me as far as excitement for seeing the beam, these 405's did with some match burning.
 
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Hi, Peter. Yeah, I'm sure Pman gave you an exceptional one. I have had many of these over the years and mine just don't meter that high. I used to like popping balloons and lighting wood up, but never really got into lighting matches. I got some white tipped matches to use as an example of high energy density beams, but that is pretty much it. :)
 
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---- from china w/ free $hip= ===405 pens for 3$usd--most are > 60 mW.. so 4$usd is not really a super deal imo..
 
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I went back and checked. I have one 405nm pen laser left and it metered at 45 mW. I have other wavelengths as well, but they are all over the place in power output. I don't believe I ever got one of the 405nm that was as high as 70 mW, or even 60 mW. I kept the one that was the highest I got.
 




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