…like the one generated by this portable military laser?
as long as they don’t let any light through, yes.
Then it would be called a “blindfold”.
In which case, they would be useless as eyewear, now wouldn’t they? The answer is, it depends. It depends on the strength of the incident beam, the amount of dilation of your pupils at the time of exposure, the wavelength of the laser radiation and the attentuation of light at that wavelength by the glasses. I doubt if ordinary off-the-shelf mirrored sunglasses will be sufficient to fully protect you, though they may provide some minimal level of protection against the worst of the effects.
I certainly wouldn’t let anyone test that on me.
I’ve never seen a more appropriate place for the following:
“The goggles, they do nothing!”
I see you finally lost your accent.
They certainly wouldn’t do any good against an industrial-strength cutting laser.
So the notion that a mirrored surface (ie the glasses) would efficiently reflect a laser beam is overblown?
I’m not sure I’d want to be where the laser beam was being reflected to, either.
Yes. The reason you can see through them is, obviously, because they let SOME percentage of the light through. Typical mirrored sunglasses reflect about 80-85% of the incident light; the rest is either transmitted or absorbed by the lenses.
Even mirrored sunglasses let some light through, or you couldn’t see through them. If the light they let through happens to be the wavelength of the laser beam, it would be just like looking at the beam. A lot of lasers don’t operate in the visible range of the spectrum, the only way you can see them is with something like smoke in the air. If they are not visible, then a mirrored surface that reflects some visible light might not be a very good protection.
It’s not whether the glasses are mirrored, it’s what fraction of the impinging light gets through. With sunglasses that’s typically between 1 and 10%. For a laser, that’s nothing. It would stuill hurt you.
They do manufacture laser goggles for laboratory safety, and these typically have optical densities of 4 or higher. (For comparison, 10% transmission is OD 1, 1% is OD2, so normally glasses are between 1 and 2. OD4 is 0.01% transmission). This is achieved by the use of absorbing dyes, thin film coatings, or holograms, and sometimes by all three (especially if you need protection at multiple wavelengths). Edmunds sells lab goggles of this type for protection from common lasers. The more optical density you require, and the more wavelengths you need protection from, the higher the cost.
Of course, you can protect yourself from all wavelengths by wearing a brick on your face, but then you couldn’t see at all. The trick is being protected yet having some vision.
Not unless this putative “smoke” is fluorescing in the visible spectrum. Ordinary smoke or fog might scatter the light making a visible-spectrum laser beam more easily visible, but an IR or UV beam will still be invisible.
I wonder if night vision goggles would protect you.
Minor nitpick - As long as the beam of light is in the visible spectrum then you’ll be able to see it when it scatters off anything, whether it’s the wall or smoke in the air. That’s why you can see your headlight beams in the fog, flashlight beams in the campfire smoke or a laser beam in mist at the groovy Laser Show.
If the light is not in the visible spectrum then you won’t be able to see it no matter what is in the air (unless you shine it on something that flouresces under that wavelength, I suppose). An IR or UV laser beam is pretty much invisible…for example you don’t see beams of light coming out of your TV remote control, even if someone is smoking up a storm in your den.
Don’t night vision goggles amplify light, making them useful in near dark conditions? Wearing them to look at a candle, for example, I thought, would probably blind you, at least temporarily.
Can you set the PHASR on stun AND kill?
That depends on the night vision goggles. The simplest sort of night vision goggles is just a pair of binoculars with really big primaries. These would assuredly make the damage worse. There may be some which electronically amplify the light indiscriminately, and these could also make the damage worse. But I think (and feel free to correct me on this) most of them nowadays consist of a digital camera and display for each eye. In this case, it would be trivially easy to build in safeguards such that the display can’t get so bright as to blind the wearer. So this sort would offer complete protection against a blinding weapon.
I’ve never seen a passive optical device referred to as “night vision” - have you?
I t hought they still used microchannel plates to “amplify” light - there are no digital signals involved. A photocathod converts light into electrons, and the electrons are accelerated and amplified by a strong electrical field before hitting a phosphor screen.
But I think you are correct in that its output brightness is limited, and cannot damage your eyes.