An optical unit of embodiments of the present disclosure includes a phase difference layer including a UV absorbent, and a linear polarization layer on the phase difference layer. The phase difference layer may further includes a base film, a liquid crystal layer, and an overcoat layer on the liquid crystal layer. The resulting optical unit and the organic light emitting display including the same may have improved polarization characteristics and optical characteristics such as transmittance, and excellent external light anti-reflection characteristics and flexibility.