Patent ID: 7109651

Claim:
An organic electroluminescence cell comprising: at least one organic layer; and a pair of electrodes serving as an anode and a cathode respectively; said organic layer including a light-emitting layer and being sandwiched between said pair of electrodes, at least one of said pair of electrodes being provided as a transparent electrode, said organic electroluminescence cell being formed to satisfy the expression B 0 <B θ in which B 0 is a frontal luminance value of luminescence radiated from a light extraction surface, and B θ is a luminance value of said luminescence at an angle of from 50° to 70°; and wherein, said organic electroluminescence cell further comprises a reflection/refraction angle disturbance region being provided substantially without interposition of any air layer so that said transparent electrode is between said light-emitting layer and said reflection/refraction angle disturbance region, and so that the angle of reflection/refraction of said luminescence is disturbed while said luminescence is output from said light-emitting layer through said transparent electrode wherein, one of said anode and said cathode is a transparent electrode and the other is a reflective electrode; and said organic electroluminescence cell satisfies the expression (0.3/n)λ<d<(0.5/n)λ in which d (nm) is a distance between an approximate center portion of a hole-electron recombination light-emitting region and said reflective electrode, λ (nm) is a peak wavelength of a fluorescence spectrum of a material used in said light-emitting layer, and n is a refractive index of said organic layer between said light-emitting layer and said reflective electrode.