Protective glasses fiber laser

[Ricky Mai]

Hello,

We bought a fiber laser from China and asked for protective glasses for this laser with 1064nm wavelength.
We received 2 glasses.
Is there a way I can check or test to make sure that these glasses are the correct ones for 1064nm wavelength?
There are no markings on the glasses to identify them.
I can see the red beam and also the light from burning the metal when wearing the glasses.

[Bill George]

Neither the red laser light nor the glow or sparks from the laser etching metal are going to harm your eyes. Safety glasses to protect your eyes are always a good idea. If your are lasering reflective material or a mirror you might have an issue.

[Ricky Mai]

Neither the red laser light nor the glow or sparks from the laser etching metal are going to harm your eyes. Safety glasses to protect your eyes are always a good idea. If your are lasering reflective material or a mirror you might have an issue.

Yes, thank you.
The glasses would be needed to protect you from the laser light if it would reflect.
But is there a way to make sure that the glasses I have are the right ones? I read that each wavelength needs different protective glasses to protect you from the reflection of that laser.

[Bill George]

Well I have no way of knowing, if they were sold in USA they would need to have approvals from some agency. Frankly I have a fiber and have amber color glasses I wear only if I am looking long term at the work piece.

[Scott Shepherd]

Well I have no way of knowing, if they were sold in USA they would need to have approvals from some agency. Frankly I have a fiber and have amber color glasses I wear only if I am looking long term at the work piece.


That's VERY dangerous. That wavelength does not stimulate a blink reflex and will burn a spot in the back of your retina that cannot be repaired. I would NEVER use a fiber laser without protective glass(es).

[Kev Williams]

There IS one way to test-- engrave the lens...

There's two types of safety lenses (that I know of), those that ABSORB the laser light, and those that REFLECT it.

Supposedly the absorption type are better because if they're scratched, they'll still work, whereas the refection type are simply coated, and a scratch will allow light thru.

get a small piece of metal easily marked by the fiber, say, some black trophy aluminum, the size of the lens or so, then scotch tape it to the the BACK of the left lens, black side toward the lens. Now set up the glasses so that you can engrave the bottom left corner of the FRONT of the lens. Try to focus the laser between the surface of the lens and the metal on the other side. Now enter a 5mm tall letter "A", and red-light it it's position in the bottom left corner.

Hatch the "A" at .08, one hatch is fine. make sure it's where you want the lens engraved. (I'm using bottom left since that'll almost always be out of your view) Run at 40% power, 1500 speed, 50 freq.

run it--

One of three things will happen:

1- The lens will be mostly un-affected, and the metal not engraved- this means the lens is likely the reflective style
2- The lens will be engraved or melted, and the metal not engraved- this means the lens is likely the absorption style-
3- Regardless of what the lens does, if the metal engraves, FAIL !!!

As long as the lenses keep the metal from engraving, they're working...

This is how I know THESE lenses work, and are the absorption style (aside from they were advertised as such) --
352857
I was dumb enough to just hold these under the lens as the laser was running- the test proved they are as advertised, but burning the bottom left corner would've be been a wee bit smarter :D
(but my eyes actually look OVER the glob so they're still okay for me!)

[Bill George]

A fiber laser beam is directed down to the table so unless your getting reflected light from a shiny object or mirror I do not think the danger is always present. I do however have the safety colored lens glasses if needed.

[Scott Shepherd]

A fiber laser beam is directed down to the table so unless your getting reflected light from a shiny object or mirror I do not think the danger is always present. I do however have the safety colored lens glasses if needed.

Sorry Bill, that's an incorrect assumption. Fiber lasers are engraving metals, metals, when melting turn into mirrors. I have personally witnessed the damage from a reflected beam on a Ceracoted AR-15 lower (aluminum). Neither the ceracote or the aluminum was highly polished but the damage was quite real. You only get one set of eyes, protect them at all costs.

I know the reflection happened because you could read the text on the item it reflected on to.

[John Lifer]

Scott, thanks for sharing your observations. I'll be wearing my glasses!