having or employing wavelengths shorter than light but longer than X-rays; lying outside the visible spectrum at its violet end; "ultraviolet radiation"; "an ultraviolet lamp"
百科解釋
Ultraviolet (UV) light is electromagnetic radiation with a wavelength shorter than that of visible light, but longer than X-rays, that is, in the range 10 nm to 400?nm, corresponding to photon energies from 3?eV to 124?eV. It is so-named because the spectrum consists of electromagnetic waves with frequencies higher than those that humans identify as the colour violet.