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Why Protesters In Cairo Use Laser Pointers
New submitter Ahmed Shaban writes "Why do protesters in Cairo use laser pointers? At the beginning, they were used to light up snipers on rooftops. Later, it just became fashionable to use them, and such things spread very fast among the youth of Cairo, who can find the high power laser pointers for sale on the sidewalks. The article contains amazing photos of a chopper lit up by green laser pointers."
No. Laser tag have fog machines.
Atmospheric effects like fog machines and hazers are why you can see them in Laser tag.
You can see the ones in the Egypt videos because they're just really powerful. Far more powerful that what is legally available in the USA without a variance.
09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0 is the magic number.
Then, they (the military) appoint some other guy to be president.
That 'some other guy' was the head of the Egyptian Constitutional Court, and a deputy chief justice for over 2 decades, not some arbitrary pick.
"His name was James Damore."
Ha, if I relied on American news I wouldn't know a bloody thing! Thankfully I'm a European (of sorts). I never said the current situation was peaceful, or desirable. The coup was peaceful, but subsequently the opposing sides have started skirmishing, which is to be expected, and it does look like the army might be a bit more active than before in intervening. This is clearly not good. I also do have serious reservations about the principle of the army removing democratic governments. While I can't condone this, in this particular case it probably averted a civil war, so was the lesser of two evils. This is not a good situation at all, but that is not what my original post was about. I posted because half the preceding posts were full of ignorance and bigotry and it pissed me off, that's all.
Smivs on the intertubes!
If lasers are being sold for cheap on the street, odds are good that they're producing a wide range of wavelengths. The cheaper the laser, wider the range of wavelengths it emits. It's one of the reasons better lasers come with an IR filter to help reduce accidental blinding of observers.
Um, no. Not enough to say so, at least.
What makes a laser a laser is that it is a single wavelength. The light amplification process itself only works on a specific wavelength, and weeds out other light. You have to put extra circuitry into a laser to get it to produce a wider range.
If an aircraft is on auto-pilot, there's negligible risk.
If an aircraft is currently under human control while cruising, there's a slight risk.
If an aircraft is under human control while taking off, landing or performing any sort of maneuver, there's a reasonably significant risk.
Have you ever had someone shine a bright flashlight in your face? It's a lot like that. It causes you to jerk away, confuses you, and partially blinds you for anywhere from a few seconds to several minutes. Any of those can be deadly given that the person with the laser probably doesn't know if the aircraft is on autopilot or is preparing to land.
It's one of those laws where, sure, 98% of the time nothing bad will happen if you do it. But that last little bit of a time, something *really* bad could happen. So it's a felony.
Nope, just mail order that mofo. These guys sell 1W+ blue lasers:
Wicked Lasers -- any colour, any power, get em before they're gone.
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ECHELON is a government program to find words like bomb, jihad, plutonium, assassinate, and anarchy.
Some laser pointers do put out IR wavelengths as a byproduct of the way they're built. Low-power laser pointers aren't a problem, the IR simply isn't powerful enough to do anything. But with 100mW+ laser being sold to ordinary people, there is a very real IR hazard from cheaply-made badly-filtered (or not filtered at all) laser pointers, especially green laser pointers.
The reason it's so dangerous is that unless you have special dual-wavelength safety glasses, they'll only filter out the visible light, leaving the IR output to wreck havok on your eyes.
http://en.wikipedia.org/wiki/Laser_pointer#Infrared_hazards_of_DPSS_laser_pointers
Eat the rich.
I am sorry but you are plain wrong! "Enough energy to vapourize a ship" can be achieved with an infrared laser (photons of energy below 1 eV). Even if you allow for multiphoton interactions it is orders of magnitude below the threshold for the pair creation (1.02 MeV for electron-positron) . There aro no lasers that produce photons in MeV range. Also, the annihilation of electron and positron, which is the lowest energy particle-antiparticle anihilation, produces gama photons ~.51 MeV which are quite invisible to humans.