Patent ID: 7510784

Claim:
A light emitting device, comprising: a light emitting element; and a luminescent medium formed on the light emitting element; wherein: the luminescent medium comprises a fluorine-based polymer and the rare earth complex dispersed therein, the rare earth complex being represented by the following formula (2): wherein Ln is a rare earth metal ion selected from the group consisting of europium, terbium and erbium; X and Y are the same or different and are individually O, S or Se; R 1 , R 2 , R 3 , R 4 , R 5 and R 6 are the same or different, excluding a situation where R 1 , R 2 , R 3 and R 4 are all the same as each other, and are individually an alkyl or alkoxy group of a linear or branched structure having not more than 20 carbon atoms, a phenyl group, a biphenyl group, a naphthyl group, a heterocyclic group or a substitution product of any of these groups; n is an integer ranging from 2 to 20; m and p are respectively an integer ranging from 1 to 5; and Z and W are the same or different and are individually a hydrogen atom, a deuterium atom, a halogen atom or an alkyl group.