Eye protecion for CO2 lasers. To wear or not to wear?
I was thinking… a dog whistle can’t hurt the human ear because our “sensors” can’t detect that high frequency.
The CO2 laser is an infrared light that wont excite our visual sensors cos like the dog whistle its out of range so we don’t see it.
What do you make of it?
Well you are taking a risk that you don’t need too…after all you only have two eyes.
except your eyes cornea will focus the beam and fry the optic nerve, dont risk it.
@Chris_Hurley Definitely! ,Better be on the safe side. (pun intended) I’m just brainstorming the physics/optics/dynamics around the subject.
@Domm434 I’m sorry bro but I don’t buy that. How come the eyes will focus on some it can’t perceive?
Maybe your eye can’t “perceive” the radiation but the eye tissue will definitely know it’s there. (cue sizzle sound).
Radiation is mostly unseen. You can’t see the radiation from a microwave ether. Just it’s effect.
I thought CO2 lasers made Ultraviolet light. UV is harmful to your eyes focused or not.
co2 is up in the IR spectrum wheras UV is around 350-500nm co2 is 10600nm
Bottom line: you get flashed by this beam your eyes WILL be damaged at some level …
Only takes a second to blind or partially blind/damage the eye.
co2 laser is IR and will be absorbed by the front surface of the eye (cornea) and wont pass through to damage the retina, but those front bits of the eye will crisp up really quickly if hit by 40W of laser, fortunately lots of common materials can block/absorb that light, including see through ones like polycarbonate, acrylic and glass.For more interesting facts read: https://www.repairfaq.org/sam/laserco2.htm
Just be smart…don’t stare into the beam! Wear simple safety glasses, keep the door closed and you will be alright.
If you think your ears cant get hurt from a sound pressure you can not hear, then you dont know much about sound. you can and WILL damage your hearing at extremely high sound pressures of ultrasonic audio.
My understanding was that your cornea will absorb the light, so you’re not going to hurt your optic nerve, but you will burn a hole into your eye. Of course you aren’t going to be staring directly into the beam…
It is very difficult to get a direct eye strike that would damage your eye when dealing with a CO2 laser. The beam is not focused for one, and will scatter the further away from the source you are. I did a test and from 18" away the unfocused beam from my K40 took just over 30 seconds to make a noticable mark on the acrylic safety glasses I use. So unless you are sticking your head inside the laser under the focus lens the is minimal chance of doing any damage to your eyesight, you have a better chance of being hit by lightning. But freak accidents can and do happen, so I always wear the acrylic safety glasses. But buying $100+ laser safety glasses is unnecessary.
@funinthefalls Touché!
I assure you that the invisible and unfocused laser beam will burn you at the right distance. Shortly after getting my laser cutter, I stupidly stuck my hand in the path of the beam and my finger suffered an instant burn accompanied by the sound of bacon frying and the smell of burnt skin. Don’t risk it!
I was maintaining an 80W laser cutter and was a bit worried that the users had allowed the tray under the cutting bed to fill with plywood shapes. So 20cm under the bed was a pile of wood, getting hit by any stray beam that had cut through the next bit of work.
However, the beam is only slightly divergent as it goes around the mirror system. After focussing, it diverges faster once it’s passed the focus point.
I ran the laser on to the woodpile for several seconds and didn’t get even a burn mark. I wouldn’t put my eye there, but yes, after the lens the power does drop off fairly fast.
@artag the laser beam diverges at a mathematically predictable rate as it leaves the
tube and continues diverging until it hits the objective lense which refocuses it and the divergence repeats at a different rate. Mirrors have no effect on divergence.
Guys, this discussion make me uncomfortable, it doesn’t matter how you damage your eyes its permanent. You can argue that normally protection isn’t required. You wear protection and have interlocks for the times when the unexpected and unexplained “a shit” happens.
I’ve got a spot in my field of vision from reflected emissions off a part I was cutting before I bought a set of safety glasses, and it’s been there for about 2 months. I found that running without glasses, even with the amber-tinted cover in place, my eyes would get sore and I would experience something similar to welders flash the next morning. I’m not talking about direct beam strikes, this is merely the reflection.
I figured if the reflection could do that kind of harm, I needed safety glasses. I picked up a set of the LightObject CO2 glasses, and I just put them on when I turn the laser on, and take them off when I’m done.
Can I say for sure that they work? Well, my eyes don’t feel sandy after a couple hours of lasering anymore, and even if that’s a placebo, for $35, it’s a worthwhile safety measure for me. I’ve only got one good eye, and I don’t intend to fry it with this thing.
Don’t be cheap - if you can afford the laser, you can afford the proper protection equipment to keep from destroying your most important sensory organs.