An embodiment of the invention relates to a light-emitting device which comprises a radiation source (5) emitting radiation of a first wavelength, a fiber-optic waveguide (10) into which the radiation emitted by the radiation source is injected, and a converter material (15) which converts the radiation transported by the fiber-optic waveguide (10) to light (20) of a second, longer wavelength. A light-emitting device of said type may have an improved light conversion efficiency.