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how Visible Light frequencies add up

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neptune

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Hi,
if i have two visible light waves (monochromatic) of different freq. and i mix them up then how would i calculate resultant frequency ?
 
https://en.wikipedia.org/wiki/Optical_heterodyne_detection

We can't measure it the same as RF or acoustical heterodyning because the wavelengths are so small, but it follows the exact same laws, detection is the pain in the rear part. The details are way of my head, but then again that's why it's a field being actively studied.
 
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Unless the mixing is done in a non-linear medium the mix will remain just that...a mix with the frequencies unchanged.
 
Unless the mixing is done in a non-linear medium the mix will remain just that...a mix with the frequencies unchanged.
what do you mean pls explain ?
 
https://en.wikipedia.org/wiki/Optical_heterodyne_detection
We can't measure it the same as RF or acoustical heterodyning because the wavelengths are so small, but it follows the exact same laws, detection is the pain in the rear part. The details are way of my head, but then again that's why it's a field being actively studied.
Visible light must follow some mathematical formula to add two colours to make other colours.
like R+G = Y , red = 430–480 THz, green = 540–610 THz to yellow = 510–540 THz
 
I think you are mixing two different principles here. One is heterodyning as mentioned above and refers generating sum and difference frequencies.

The other (post#5) is our perception of color based on the differential excitation of the cones in our eyes. Check: https://en.wikipedia.org/wiki/Color_perception . It might also be worth searching on "color blindness."

John
 
I think you are mixing two different principles here. One is heterodyning as mentioned above and refers generating sum and difference frequencies.
The other (post#5) is our perception of color based on the differential excitation of the cones in our eyes. Check: https://en.wikipedia.org/wiki/Color_perception . It might also be worth searching on "color blindness."
John
Let me make it clear - if i have 2 light waves 1st light -200THz and 2nd light-300THz .. now we mix them up what would be the resultant frequency
 
It all depends. How do you propose to 'mix them up'? Is a non-linear medium involved? If so, what is it?
 
Let me make it clear - if i have 2 light waves 1st light -200THz and 2nd light-300THz .. now we mix them up what would be the resultant frequency


Hi,

If you shine two different color lights onto a white surface you get the 'mix' but the mix is just what the eye interprets when it sees two frequencies instead of one. They dont actually change frequency, you just get two frequencies instead of one.
 
I am mixing two lasers in Vaccum , one beam extrapolated on other
 
I am mixing two lasers in Vaccum
In that case there is no medium involved so IMO there won't be any sum or difference frequency generation.
 
so if i mix up Red and green Laser in vaccum then i wont get yellow light ?
 
I think MrAl put it best already.

To re-state what I think he said:

The two frequencies will not mix in a vacuum.

It is only your brain that will interpret the reception of red and green to produce yellow in your head.

Outside of your head the two frequencies will remain independent and no mixing will occur.

Not sure if this helps
 
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It is only your brain that will interpret the reception of red and green to produce yellow in your head.
that makes it clear.
Nigel- here's how i'm gonna mix them up
 
As Nigel said the light won't 'mix' at least not on a fundamental level, if you converge a red and green laser on a point you will see yellow light, but the fundamental frequency of the light won't change, if you look at it on a spectrograph you'll still see red and green only. Human visual perception is a lot more complicated than people take for granted.
 
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