Patent ID: 7723740

Claim:
A light emitting device comprising: at least two kinds of fluorescent material which are to be substantially directly excited, by light emitted from an excitation source having a principal emission peak in a wavelength region of from 250 nm to 420 nm, so as to emit light that is blended to produce light of various colors, wherein said at least two kinds of fluorescent material include at least one of (i) an oxynitride-based fluorescent material having crystallinity, and represented by a chemical formula of LM 2 O 2 N 2 :R or LM 2 Q T O 2 N 2+T :R (0<T<0.5), where L is at least one kind of Group II element selected from the group consisting of Mg, Ca, Sr, Ba and Zn; M is at least one kind of Group IV element selected from the group consisting of C and Si; Q is Boron; O is oxygen; N is nitrogen; and R is a rare earth element; and (ii) a nitride-based fluorescent material, and wherein light emitting efficiency of said at least two kinds of fluorescent material when excited by light emitted from the excitation source is at least 60% of a maximum light emission efficiency over the wavelength region of from 250 to 420 nm.