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Do lasers refract at different freq?

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Do lasers refract at differenct frequencies? When a laser refracts off an object does the refracted em waves of the laser bounce off at different frequencies? How are the laser frequencies measured?

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I don't think frequency changes. If you had different frequencies for the incident and refracted waves you'd wind up with phase discontinuities at the interface, I believe.


I guess the formal way to say that is to say that you can't satisfy the boundary conditions for Maxwell's equations at the interface if you presume a transmitted wave that differs in frequency from the incident wave. I'd like to also say that this has to do with keeping the same amount of energy in each photon, which requires the same frequency, but I don't have my head around that well enough right now to make it stick.

Edited by KipIngram

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Do lasers refract at differenct frequencies? When a laser refracts off an object does the refracted em waves of the laser bounce off at different frequencies? How are the laser frequencies measured?

 

 

Lasers are generally in a narrow frequency band, and "bouncing" sounds like reflection, not refraction. Different frequencies will refract differently (dispersion) and there are optical components used for dispersion compensation in certain lasers. Typically in pulsed lasers, because dispersion causes the pulses to broaden. In many situations dispersion is too small of an effect to notice.

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My 532nm handheld green laser does not refract (at least not enough to notice visually) into any other other wavelenghts when shot through a prism.

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My 532nm handheld green laser does not refract (at least not enough to notice visually) into any other other wavelenghts when shot through a prism.

 

 

The physical separation for a laser with a frequency bandwidth of several MHz is minuscule.

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Do lasers refract at differenct frequencies? When a laser refracts off an object does the refracted em waves of the laser bounce off at different frequencies? How are the laser frequencies measured?

 

 

As far as refraction (separation of the beam into other wavelenghts) swansont in right.

As far as reflection (splitting the beam) here's a photo of what happens when you shine a 532nm/350mW green laser into a 0,4 carat cut diamond - you just get a bunch of beams:

 

 

post-120020-0-69515000-1495114673_thumb.jpg

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Depends on the laser.  Solid state lasers will generally have just one line (and perhaps a line from the pump laser if it uses one, but pump lasers are usually in the infrared range, therefore invisible...and they SHOULD be filtered anyway)  Gas lasers,  on the other hand will have several "spots" because of the mix of gasses used.

Wavelegths can be measured using a diffraction grating and measuring the amount each beam is refracted,  the amount the light is refracted is dependant on the wavelength and frequency can be calculated simply using the formula...

 

f= c/w

where c equals the speed of light

w  equals the wavelength

 

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