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Disney lost their old camera tech used to make a "yellow screen" with sodium vapor lights.
It's actually better than a green screen because the yellow light is so specific that even if you remove that particular frequency of light, everything else still looks fine. You can do all sorts of things that would normally be very difficult to pull off with any of our green screen tech (like drinking water in a clear bottle or wearing a rainbow dress).
https://www.youtube.com/watch?v=UQuIVsNzqDk
Considering LEDs are so good at producing a very tight wavelength, I wonder if this could be replicated with more energy efficient lamps.
Or if non visible spectrum lights can be used to make similar alpha channel masks that don't affect lighting the scene.
A laser, maybe, but definitely not LEDs. Vapor/gas lamps produce the narrowest frequency bands possible, because it comes from very well defined atomic transitions (Hz range). LEDs produce frequency bands with widths in the GHz/THz range, while semiconductor lasers can maybe reach KHz if they are really good. So, unfortunately, for this type of applications, vapor lamps would probably still be needed.
Source: I work with lasers and spectroscopy.
Edit: very good idea about using non-visible light!