In OLED displays each pixel emits individually light just by the surface, so that the displayed image is completely readable from any viewing angle. To compare, in LCD technology light-emitting layer is located from below and on this layer, there is applied light transmissive and color filtering matrix. Created in such display image characterize with very good optical parameters only when you look at it from right angle. Any different viewing angle results in lower light transmission. This causes a visible deterioration of image quality that is reflected in brightness and contrast decrease.