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mfukar t1_j7g1qjw wrote

Reply to comment by zerpa in Why are green and red laser pointers so cheap and available, but yellow ones not so much? by SurprisedPotato

Because neither red nor green, in terms of frequency/wavelength, are yellow. The colour wheel is about visual perception.

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zerpa t1_j7hnytj wrote

I don't understand your point. The brain can't tell the difference between yellow wavelength and the mix of red+green that give the same excitation of red/green photoreceptors.

I get that it's not a coherent light/laser anymore, but it should still be possible to create a yellow pointer, if you can join the two beams and align them precisely.

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dramignophyte t1_j7ip4he wrote

I was typing a wrong response but I can tell you why it doesn't work: lasers run parallel and it's kind of an important aspect of them. In order to mix something, they need to converge. So you need to adjust the focus point of the two lasers to account for distance. I was thinking maybe fiber optics but that wouldn't change the fact you can't change the position of light in that way or it will diffuse or not converge to mix the colors.

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