What is the "blue light" often discussed in relation to human melatonin production, sleep/wake cycles, etc.? A Google search seems to define it as light of a particular wavelength, suggesting that it literally means "light that's blue in color," but many articles seem to attribute blue light to the light emitted from computer/TV/etc. screens, which is not inherently blue in color.
What exactly is blue light? For example, would adjusting the "blueness" of a colored light bulb, as if raising and lowering the "B" slider in an "RGB" color selector (raising "B" in the morning and lowering "B" in the evening), have at least a hypothetical positive impact on human circadian rhythms?