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FrozenGate by Avery

3w laser safety glasses

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Dec 28, 2015
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I just bought a 3.4W 455nm laser and expect it to arrive Monday. I'm not new to the hobby by any means but I've never owned a laser that's been anywhere near that power. I already have the glasses I'll need but my question is, at that power, is he dot that you see even through the glasses capeable of causing eye damage? I imagine that once it comes in I'll try burning a few things with it and will want to look at the point that is burning but won't if it could be dangerous.
 





What glasses did you get? It should be completely safe to view the dot with the glasses on or while burning things. The Eagle Pair that so many here prefer are supposed to protect you enough to view the dot of a 10W laser, I don't know if anyone has tested that though. That's only viewing the dot, that's not taking a direct hit. I have a laser about 3W or a little over and I have two pairs of cheaper glasses that work good enough, though at that power I don't know if they would protect from a direct hit. So don't let that laser slip out of your hand or roll off of a table etc. and if viewing the beam without glasses make sure not to look directly at the dot and have it pointed at something that you won't set on fire, you will find that it is a potential fire hazard when focused.

Alan
 
What glasses did you get? It should be completely safe to view the dot with the glasses on or while burning things. The Eagle Pair that so many here prefer are supposed to protect you enough to view the dot of a 10W laser, I don't know if anyone has tested that though. That's only viewing the dot, that's not taking a direct hit. I have a laser about 3W or a little over and I have two pairs of cheaper glasses that work good enough, though at that power I don't know if they would protect from a direct hit. So don't let that laser slip out of your hand or roll off of a table etc. and if viewing the beam without glasses make sure not to look directly at the dot and have it pointed at something that you won't set on fire, you will find that it is a potential fire hazard when focused.

Alan

Thank you, that's exactly what I needed to know. I wrote that when I was half asleep last night and messed up a little bit. It's a 445nm laser not 455. The laser is supposed to come with glasses and I have no idea what kind thy are, but I have an eagle eye pair that I got for my infrered laser that says it protects from a range of 190nm to 450nm. I don't know if it's cause for concern that the range ends just 5nm past what the laser is or not, but I figure that will be easy enough to test.
 
If you can see the beam with the glasses on then it's not good enough, with the glasses on the dot should not be very bright, not bright enough to be uncomfortable to look at. If you view the dot without glasses there is some disagreement about what distance it needs to be, but this will vary depending on the circumstances and reflectivity of the surface, generally just across the room it would usually be too bright to look at, when focused it can make a dot brighter than the sun. Once again be careful not to burn anything you don't want to.

Alan
 
If you can see the beam with the glasses on then it's not good enough, with the glasses on the dot should not be very bright, not bright enough to be uncomfortable to look at. If you view the dot without glasses there is some disagreement about what distance it needs to be, but this will vary depending on the circumstances and reflectivity of the surface, generally just across the room it would usually be too bright to look at, when focused it can make a dot brighter than the sun. Once again be careful not to burn anything you don't want to.

Alan

I will. Thank you for all the help!
 
I just bought a 3.4W 455nm laser and expect it to arrive Monday. I'm not new to the hobby by any means but I've never owned a laser that's been anywhere near that power. I already have the glasses I'll need but my question is, at that power, is he dot that you see even through the glasses capeable of causing eye damage? I imagine that once it comes in I'll try burning a few things with it and will want to look at the point that is burning but won't if it could be dangerous.


The spec to look for is the Optical Density, or OD. This calculator computes what you need based on the wavelength and optical power output. For yours, it comes out at OD > 3.53. If you have goggles, look up its OD capability.

If you're going to buy some goggles, like many others here I also recommend Survival Laser. If you're in the USA, be sure to order from their USA Website.
 
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When you get the first laser don't be like this IDIOT !!

 
Last edited:
I just bought a 3.4W 455nm laser and expect it to arrive Monday. I'm not new to the hobby by any means but I've never owned a laser that's been anywhere near that power. I already have the glasses I'll need but my question is, at that power, is he dot that you see even through the glasses capeable of causing eye damage? I imagine that once it comes in I'll try burning a few things with it and will want to look at the point that is burning but won't if it could be dangerous.


The answer is; “It depends.” The glasses must be able to block enough of the laser energy in order to minimize the harm level. At the same time, they cannot block too much of it, or you would not be able to see the beam. The ‘strength’ of laser glasses is measured at specific wavelengths in values of Optical Density or ‘OD’. The higher the OD, the more of the specific energy is blocked. The second factor is how the beam is viewed. Either directly (Intrabeam ), or through a specular (mirror like ) reflection. Running a calculation for this laser, the Hazard Zone for Intrabeam viewing is less than 1912 feet. That means to view that beam directly, without causing damage to your eyes, you would have to be almost ½ of a mile away from it! For diffuse viewing, like looking at a dot on a wall, you would have to be more than 8 inches away from the dot to view it safely. HOWEVER to be safe you should ALWAYS wear properly rated glasses while operating an open beam laser because accidents can happen. In this example an OD of 3.5 or greater is called for. In addition, this brings us to the third factor in safe viewing of a laser beam, length of exposure. All of the limits expressed so far have been with an exposure time of ¼ of a second. That value is chosen because it is approximately the amount of time it takes a person to blink their eyes closed. Closing one’s eyes can actually protect from laser exposure, depending on the intensity.

With a laser of this power and wavelength, glasses of 3.5 OD will block the beam entirely, you will not be able to see it. Therefore, to see the beam, and still protect yourself, you need glasses rated at a lower OD. I would recommend an OD of at least 1.5. They will protect against a very short accidental exposure from a direct strike from the beam.

Hope this is helpful!
 
I'm by no means recomending eye protection for anyone as I'm not an optometrist. I did order a 99 cent pair of safety glasses with a Chinese order I made just to play with. My nubm 44 does NOT shine through them (no dot when shined through them). I don't use these glasses and only bought them to test.
Danny
 





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