A supported transparent electrode for an OLED, includes, in succession: (i) a transparent substrate made of mineral glass; (ii) a scattering layer formed from a high-index enamel containing at least 30% by weight Bi2O3; (iii) a barrier layer of at least one dielectric metal oxide chosen from the group consisting of Al2O3, TiO2, ZrO2 and HfO2, deposited by ALD; and (iv) a layer of a transparent conductive oxide (TCO).