Safety glasses question (RGB)

[dnar]

Hi All.

I bought a set of 532nm safety glassed last year when I started experimenting with 532nm. Since playing with 445 and 658nm since then, I have not had a set to suit either wavelength. Although I have been very careful, I feel I have cheated injury and been lucky to date.

As my projector build is almost ready to commence, I am nervous about not having suitable protection for RGB and can see that protection is necessary when lining up dichros and the like.

What do you guys use for protection when lining up your RGB's?

Thanks. Wayne.

[LaNeK779]

there are rgb safety glasses available

ct lasers have them, stanwax has them (OD 4) and many others should carry this sort of safety gear, too

the thing is, last time i contacted mark a couple of months ago he told me that he was expecting some sort of better spec goggles and rob is rather hard to find these days (tried twice)

i guess i will have to follow up on both of them

[allthatwhichis]

I am not sure if any of the RGB safety glasses are worth it; actually the concept confuses me. If you have coating for all 3 wavelengths, what color can you "see"?

I turn the power down on all 3 lasers in software to align my projector and don't wear goggles.

[laser_freak]

I am not sure if any of the RGB safety glasses are worth it; actually the concept confuses me. If you have coating for all 3 wavelengths, what color can you "see"?

I turn the power down on all 3 lasers in software to align my projector and don't wear goggles.

My understanding is that they only block narrow ranges of wavelengths. Maybe 470-480, 530-540, and 640-650. The ranges might be larger, and non-linear to encompass other wavelengths, however just blocking 3 different ranges of wavelengths does not block all of the light. You would of course still see all of the wavelengths in between.

[LaNeK779]

well, i guess these goggles don't actually block light they just pass a very very small percentage of it

turning the power all the way down and using sunglasses for added comfort is my chosen method, as a test, i shot 200mw of red though them and measured 60mw on the other side, so with the power all the way down, almost nothing passes through, but you can still see what you are doing.

Of course i avoid taking direct hits, it is not so easy to find yourself in the beam path, even during alignment. i always measure the leakage through the dichros, so i know how powerfull these waste beams are, as these are a more serious threat for me, just lurking there in mid air

i also use a camera to take pictures of the dichros using flash, so that i can really see the spot and not all the haze around it. after a series of photos, and subsequent tuning of the mounts, the near field is spot on.

then, i take a series of photos while scanning various frames to do the far field alignment

hope this helps

[blowfly]

I think eye protection is pretty important. During alignment is the most dangerous time in my experience. I'm a little paranoid about it but hey, it's my eyeballs . The RGB googles don't seem like the way to go because 1) you can't see much through them so conditions have just right to use them 2) my understanding is all the RGB glasses are coated as opposed to being made of the material that reflects the light. Coated glasses scratch easier and become less useful.

I have one pair of glasses the block red wavelenghts and a second pair that block blue and green. It does mean I need switch back an forth sometimes. Make sure you get glasses appropriate to your laser power. If I remember correctly (don't take my word for it) the OD rating is the log base 10 of the protection you get.

[mixedgas]

Video camera, if you can't turn the power down.

Steve

[dnar]

Thanks everyone.

[JasonB]

Hi Dnar - Thanks for bringing up this topic! Considering that I'm a novice just getting going with a projector build here is what I did...

For what its worth I took a 'risk' and purchased two sets of safety goggles from o-like when I ordered their 1 Watt 445nm Blue laser. .

Each purchase I've made from o-like has increased my confidence in them - more about that later!
The 445nm goggles ($54) came with a nice case, the 532 nm pair ($19) came without one... They seem to work well although I don't have a power meter to actually verify. When the project is done I'll drag it to work and borrow the lab's laser power meter...

1000 mW of blue quite frankly makes me a little nervous (and giddy, is that OK? ) and I would not even think of aligning the dicros without eye protection. And the 100-180 mW of green is enough to make you think when catching a beam in the eye on accident....

These are the goggles I'm satisfied with:
1 x 405nm,445nm,808nm,1064nm safety goggles/200-450,800-2000nm (OLLS1064) = $45.99
1 x 405nm,450nm,473nm,532nm laser safety goggles (OLGLG532) = $19.99

If anyone has any comments or data on these goggles then certainly would love to hear it!

Jason

[norty303]

Low powers and being very careful with angles get me by. I find safety gear brings a false sense of security that changes your actions, which may well bite you in the arse when you're NOT using the safety gear.

I take great pains to avoid all of the horizontal and vertical angles that exist when moving around, e.g. not leaning over the scanner block, not crouching down by the side.

Diffuse reflections are a worry for me though as they are still very intense.