In telecommunications, visible light communication is the use of visible light (light with a frequency of 400–800 THz/wavelength of 780–375 nm) as a transmission medium.

High-energy visible light (HEV light) is short-wave light in the violet/blue band from 400 to 450 nm in the visible spectrum, which has a number of purported negative biological effects, namely on circadian rhythm and retinal health (blue-light hazard), which can lead to age-related macular degeneration.