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FrozenGate by Avery

Black Laser!!!

pseudolobster said:
[quote author=motorider826 link=1213733576/24#25 date=1214020903]what if the laser outputs a specific wavelength that causes destructive interference with the light in the room. So by canceling out the light in that 'ray' then the light wouldn't reflect back at you thus creating an absence of light 'laser'. Think noise canceling headphones on steroids and crack.

yeah, maybe that could work...
but think about it... to simplify let's say the room is only being lit with one wavelength of light, since real world conditions would mean you'd need to do this for every wavelength... but at any rate, the amount of light being cast on each area of the beam would be different.. so your anti-beam would need to dynamically modulate its amplitude to match the light in the area it's passing through... of course you could have some hypothetical super-accurate super-fast sensor that detects the position and vector of every photon in the room, but in order for it to modulate the beam to match in real time it would have to calculate at faster than the speed of light, which simply isn't possible.
[/quote]
I guess i better get to work on my pen sized 687 yottaflop super computer. ;D
 





I'VE DONE IT!!!  ;D

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Image courtesy of thecheat - one of the oldies from LC and SF.
 
Doesnt a laser cancel out when it crosses directly back through a laser of the same wavelenght? Thats how they detect gravity waves, because they have two laser beams, one going north lets say, and one going south. They cancel each other out and no light is emitted.

I might have interpreted this wrong but thats what i gathered from the articles about the gravitational wave detectors:

They work by sending a coherent synchronized laser beam down two separate, perpendicular axis, like a V, with a beam splitter. When the wave contracts one axis, the light is unaffected and travels a shorter distance, while the other axis, being perpendicular to the wave front, will experience no such contractions. When the laser is reflected off the other end of the tunnel, they will return to their source out of phase, and that phase difference is what is detected. The two light sources can be passed through a screen/hole/interferometer, and then the wave nature of light takes over and out of phase light waves will will cancel each other out creating a dark spot, while in-phase light with no gravity wave present will create a bright spot. The detector only has to detect when the 'lights go out' in the center of the bright spot turning to a dark spot.

Im not sure what this has to do with black lasers but its interesting because even though a laser is being shone at a certain spot, not light is there, right? Black laser?
 
I think that's called an interferometer, where one beam is split and joined later when the two beams are out of phase so they cancel eachother out through destructive interference.I'm pretty sure though , that for destructive interference to happen , the 2 beams must be going in the same direction.That why you can't really use this to create a black laser because in a lir room you have light of many different wavelengths traveling in all directions.....
 
Ya know what you can do with a black laser?

Turn on streatlights at the middle of the day...
 
;D And you can then turn them off later with your 30mW green :P that would be wierd, the lights constantly going on and off
 
Not only would you have to detect and calculate the position and direction and wavelength of every single photon in the room, but you would also have detect and calculate the position and direction and reflective properties of every single particle in the air and on the walls. Because what good would it do to cancel out light in a straight line? It would appear to have no effect whatsoever to an observer because the only way to see that it was working would be to stare straight into the black laser beam. When you look at the dot of a black laser, you wouldn't see a black dot. You would see nothing unusual at all, the wall would look the same. Because that spot on the wall is reflecting light that is coming from various angles. You would need a laser that produced the exact wavelength at exactly the right position and direction so that it is emitted from the laser, travels to the wall and bounces off at exactly the right angle to travel exactly along the same path as some other photon from the room.

To pull that off you would not only need a machine that calculates things faster then light, but if you're using this black laser from further away than the rooms light souce, you would also need a machine that could predict photon emission before it even takes place.

So really you would need an infinitely powerful computer as well as a time machine. Nevermind actually engineering a laser that can emit all wavelengths instantaneously and switch between specific ones trillions of times a second with a specific direction and orientation. :o
 
a white laser isn't a laser.It green red and blue combined so it isn't corent.
 
Switch said:
Meh , all the technology in the world won't ever never be able to create a black laser.It just can't exist.I mean, black is the absence of light, then you put it near the term "laser", you know, light amplification etc, etc. How can light emission suck light in? The whole concept of a black laser is as absurd as a square circle. ::)
google "squircle" :P
 
um hi my black lasers dot is split down the middle >:( >:( >:( >:( >:( i think i dropped it but its not working how do i taik it apart and such in order to fix it, maybe you could pot mod it or something but i'm not very good at electronics but can you guys tell me how to fix it :-/ :-/ :-/ :-?
 
Oakwhiz said:
um hi my black lasers dot is split down the middle >:( >:( >:( >:( >:( i think i dropped it but its not working how do i taik it apart and such in order to fix it, maybe you could pot mod it or something but i'm not very good at electronics but can you guys tell me how to fix it :-/ :-/ :-/ :-?

It's obviously mode hopping. The flux capacitor needs a better heat sink to properly cool the matter/antimatter annihilation process that allows it to pump an anti-matter KTP crystal to produce anti-photons.

Or you could need new batteries. These black lasers need lots of current.
 
The black lasers suck (pun intended) the battery power real quick. You also seem to be having mode hopping issues, did you buy it from WL?

It may just be a simple case of rebuilding the whole laser from scratch.



;D
 
jamilm9 said:
a white laser isn't a laser.It green red and blue combined so it isn't  corent.

What about an Ar/Kr laser (with the correct optics of course)? Thats white light, all coherent ;)
 


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