[zakary]

It just so happens that one of my colleagues just finished a PhD creating materials which pretty much do exactly this; converting a relatively broad spectrum of light into a much narrower band of light. I’ve seen them in the lab where it’s colourless and clear to start with, and then it will convert any incident light in the blue range into a much narrower band of a specific blue colour. He has recipes for just about any colour, even into UV and IR bands. Not sure what the real world applications are though, maybe something to do with coatings for photovoltaic cells to increase efficiency

[Scene_Cast2]

There was an article about a flat nano-tech lens, but it only works for a single wavelength of light. Combining the two could result in the ultimate "pancake" black & white camera.

[etrautmann]

I'm not sure that would work well - if you're only recording a single wavelength, then the resulting black and white image wouldn't resemble a normal one, where all wavelengths are added to obtain a pixel intensity.

[rbanffy]

I can immediately see applications in IR and UV for hyperspectral imaging using cheap sensors. Your idea of PV cells is also excellent, provided the wavelength compression is efficient.

[layer8]

What’s needed is not to compress colors into one narrower band, it’s to quantize them into multiple combinations of bands (e.g. combinations of three RGB bands).

[_aavaa_]

Anything published you could point to?