LIGHT-EMITTING DEVICE WITH A LUMINESCENT MEDIUM, CORRESPONDING LIGHTING SYSTEM COMPRISING THE LIGHT

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The invention relates to a light emitting device (1) with high colour rendering comprising a wavelength converting member (2) with a luminescent medium for wavelength conversion of blue light and/or ultraviolet light (10) into red light and/or yellow and/or green light and a light source (3) emitting blue light (10) and/or ultraviolet light arranged to pump the luminescent medium, said luminescent medium essentially having a main phase of a solid state host material which is doped with Ce3+-ions. According to the invention the host material comprises ions of a further rare-earth material Ln, wherein the host material is selected such that the emission energy of the 5d-4f emission on Ce3+-ions is energetically higher than the absorption energy into an upper 4fn state of the further rare-earth material Ln, and wherein the light emission of wavelength converted light is caused by an intra-atomic 4fn-4fn transition within the ions of the further rare-earth material. The invention further relates to a corresponding lighting system comprising the light-emitting device and a corresponding luminescent medium.