If the bubbles can be coated, then the filtered spectrum can be influenced. Eg if 20-300Thz is filtered out, then we only lose heat that’s probably not really useful to plants.
Yes, this would be ideal (although I've rarely seen light measured like that - isn't wavelength almost always used?) If you could have a bandpass filter allowing in ~400-700nm light that would be kind of awesome - definitely a have-your-cake-and-eat-it-too moment. (of course with our luck there will be some process we need that we don't know about that requires the rest of the spectrum too)
