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Hopefully you guys can solve this hypothetical for me.

Suppose I have a laser which emits light at frequency $530\mathrm{THz}$ with a very narrow spectral width $1\mathrm{Hz}$.

From signal theory, as far as I understand, this represents a carrier which my eyes perceive as color green.

Now I modulate this laser with a fictional modulator with the the sine frequency of $100\mathrm{THz}$. This means that on the spectrum diagram, I would see my "modulated signal" at the frequency of $630\mathrm{THz}$ and $430\mathrm{THz}$, ergo, red and blue for my eyes.

Would such a modulator create a blue and red laser from a green laser or actually a laser of any color for that matter?

Harish Chandra Rajpoot
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KrNeki
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1 Answers1

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It is an insightful question, and the answer is "Yes". What you describe is often called "frequency mixing", and can be used to generate practically any wavelength we want. Note, however, that to modulate a laser at 100 THz, you need a source to produce a 100THz signal. And, by the way, you seem to be mixing up wavelengths and frequencies. 630 nm (wavelength) is red light, and 430 nm (wavelength) is a blue-violet color. Frequency is inversely proportional to wavelength.

S. McGrew
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