Light is part of the electromagnetic spectrum, according to modern physics.
- Shares wave properties with X-rays, microwaves and radio waves, including dispersion
- Visible light spans wavelengths from 400 nm to 700 nm
- Quantum physics attributes particle properties to light. Refraction is better explained by this theory.
Colour
Colour is a construct in the brain. It doesn’t correspond to a physical phenomenon.
- Mixing light waves of different wavelengths produces the perception of different colours
- A few narrow wavelength bands are perceived as distinct colours, called primary colours
- Primary colours are orthogonal to each other
- Mixing primary colours produces the secondary colours we perceive
- Red, green and blue are the most common primary colours, but not the only ones