OK, so if it is coherence -- then what's the generalized method to make a given EM wavelength or frequency band (light specifically, all EM wavelengths generally) coherent?
That is, in Physics, how would one take an EM wavelength/set of wavelengths/frequency/set of frequencies (or even more broadly speaking, "energy") -- and make it coherent?
That is, in Physics, how would one take an EM wavelength/set of wavelengths/frequency/set of frequencies (or even more broadly speaking, "energy") -- and make it coherent?