amp;lambda;/4 PHASE-SHIFTED FILM AND ORGANIC ELECTROLUMINESCENT IMAGE DISPLAY DEVICE

摘要

An object of the present invention is highly expressed Castle phase , thin as a reverse wavelength dispersion having the characteristics and thickness of , and reducing the bandwidth of the phase difference / 4 retardation film and the image display performance having it to provide an excellent organic electroluminescence image display apparatus . / 4 retardation film of the present invention , 23 , and the retardation in the thickness direction in the wavelength measured in an environment of relative humidity 55% 550nm (Rt) (550) is less than 150nm, if the wavelength dispersion of the retardation (Ro) this characteristic , the condition 1 as 0.72 Ro (450) / Ro (550) 0.96, also 0.83 Ro (550) / Ro (650) is in the range of 0.98, this plane refractive index as the condition 2 1.000 n _{y and} (280) / n _x (280) 3.500, as also the conditions 3, 1.05 n _y (400) / n _x (400) that is characterized 2.15 .