White light is the term for visible light that contains all wavelengths of the visible spectrum at equal intensities.
- The sun emits white light because sunlight contains all the wavelengths of the visible spectrum in roughly equal proportions.
- Light travelling through a vacuum or a medium is termed white light if it includes all wavelengths of visible light.
- Light travelling through a vacuum or air is not visible to our eyes unless it interacts with something.
- The term white light can have two meanings:
- It can refer to a combination of all wavelengths of visible light travelling through space, regardless of observation.
- What a person sees when all colours of the visible spectrum hit a white or neutral-coloured surface.