One more time......

Ok, goggles.... are there any to wear when you're working with red and green lasers at the same time? Add blue to that??? :huh2:

All I have found will do either red, or green and blue, but not all three... Somebody made the point that if you block R, G and B, what have you got left to see with... I have been using my green goggles for pointing the green one and just turning down the power of the blue and red ones when I align them.

Yes, there are no goggles that will block all primary colors at the same time. Goggles that block green usually work for blue also, because blue and green are fairly close together (in the spectrum). Since the absorption of the coatings is somewhat tapered, blue also gets blocked. But red, being farther apart, can't be blocked with the same coatings.

You'll need two goggles to work with all your lasers. First align your green and blue with that specific goggle. Then, since they're supposed to be fixed, you can take that goggle off and use the other to align the red laser. Once everything is aligned, you can take your goggles off and enjoy the show. That is, if the lasers are not so powerful that it hurts just to see the dot on a wall .

Ah - now, what about the dot on the wall, I was wondering about that - is it dangerous if it's too bright like more directly reflected light would be?

If it's just reflecting off a white wall, you should be safe. The dot will be painful to look at but for pratical purposes safe. This is because you're recieving diffuse reflections, the light is being scattered in all directions, so actually a small amount of the coherent, collimated light is reaching your eyes.

Now, this applies only to some extent. For instance, don't try that with a class IV laser. Class IV lasers even require skin protection to prevent burning.

Another factor to consider is wavelength. Green lasers are a lot "brighter" than red ones. So you can have a 500mw red laser that "looks" safe, but is not, while you may have a 100mw green that looks dangerously bright. And worst of all, you can have a class IV laser in the UV or IR region that is invisible to us, and you'd be ablivious to the dangers.

The real danger from all this comes when trying to align the laser. You run the risk of the beam hitting a mirrored surface like a metal object or mirror, and the light reflected off that object can enter your eyes. VERY dangerous.

I believe a piece of cardboard would effectively block all wavelengths. Maybe not so useful though...

I believe a piece of cardboard would effectively block all wavelengths

Click to expand...

Well, not really. I'm pretty sure it would let x-rays and other wavelengths through :laughing:

jkaiser3000 said:

Well, not really. I'm pretty sure it would let x-rays and other wavelengths through :laughing:

Click to expand...

:lolsign:
Point for jkaiser3000...