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ArcticMyst Security by Avery

Need an inexpensive laser power meter.

Joined
Dec 27, 2011
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I checked the sticky of things that a noob needs, but didn't find anything - the one that was mentioned went to a dead link.

Anyone have any suggestions on an accurate, but budget meter?

FWIW, I own a good VOM, so I have that if it helps.

Tom Steele
 





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Nov 8, 2011
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How serious are you about lasers and how much do you spend on them? If you are serious about the laser hobby then next time you feel like dropping a few hundred bucks on your next laser purchase, instead invest in an LPM. Now you will know if your $200 laser you bought from *LaserMart* is actually up to spec!
I own quite a few lasers and just recently purchased the LaserBee A and I have to say it is one of my best investments in this hobby.
 

joeyss

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Just out of curoisty....couldn't we make a semi-decent one cheap by using a solar power thing with a digital muiltimeter? We'd just have to have someone with a lpm and lasers of the same power, but different wavelengths and just derive a formula for a approximation. You get the same voltage reading no matter how big the beam is proved it hits all of it.
 
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^No. It varies with wavelength, the specific cell you're using, the angle, the spread on the cell... too many variables. It would be impractical to map them all.
 
Joined
Dec 27, 2011
Messages
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How serious are you about lasers and how much do you spend on them? If you are serious about the laser hobby then next time you feel like dropping a few hundred bucks on your next laser purchase, instead invest in an LPM. Now you will know if your $200 laser you bought from *LaserMart* is actually up to spec!
I own quite a few lasers and just recently purchased the LaserBee A and I have to say it is one of my best investments in this hobby.

I'm not that serious right now. My reasoning is that it seems like a lot of lasers are sold as <5mw to get around the law when in reality they are much hotter than that. I'd just like to know what I'm actually dealing with and know whether I have a casual pointer or something I need eye protection for when I am using it.

I know 5mw is the official limit at which you are supposed to use goggles, but is that the typical belief here on the forum?

TIA,

Tom Steele
 
Joined
Dec 11, 2011
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5mW is the limit set that "you would blink before it does damage to you", but it is often misunderstood as "5mW cannot hurt your eyes" which is not true. Specifically, wavelengths that your eyes are not as sensitive to, like 405nm and 680nm, would not cause you to blink as quickly as a 532nm beam, but do just as much damage.

I can't say what the typical belief is, but I can say better safe than sorry, and most pens that are marked as 5mW that are 405nm are ususally more than 30mW. If the beam has any chance of reflecting back towards you off a surface that isn't VERY dark and matte to that wavelength, chances are you should have goggles on unless it is a 532nm 5mW pointer that is actually putting out 4.99mW or less. Even then, damage is possible.

It's all about being safe and responsible.
 
Joined
Sep 20, 2008
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I'm not that serious right now. My reasoning is that it seems like a lot of lasers are sold as <5mw to get around the law when in reality they are much hotter than that. I'd just like to know what I'm actually dealing with and know whether I have a casual pointer or something I need eye protection for when I am using it.

I know 5mw is the official limit at which you are supposed to use goggles, but is that the typical belief here on the forum?

TIA,

Tom Steele

The ONLY way you will be sure of what power your Laser puts
out is with a calibrated Laser Power Meter...
Then you will know if it is >5mW and know when to use Laser
Eye Protection..


Jerry
 
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Sep 11, 2007
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Last edited:
Joined
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tsteele93

You wouldn't go wrong if you order LaserBee . He ships from Canada.

I am recommending him only because I own LaserBee LPM- based on my experience with his product.

Cheers
 




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