<p>PURPOSE: An organic light emitting display device is provided to control the generation of external light reflection and Newton's ring by scattering light through an optical scattering layer. CONSTITUTION: A pixel electrode(710) is formed on a substrate member. An organic light emitting layer(720) is formed on the pixel electrode. A common electrode(730) is formed on the organic light emitting layer. An optical scattering layer(650) is formed on the common electrode. The optical scattering layer is one between a crystallized organic layer and a crystallized inorganic layer. The optical scattering layer is crystallized with a thermal process. The optical scattering layer comprises silicon.</p>
