US Patent 7498738 Organic EL element and organic EL panel

A semi-transmissive film is provided underneath a transparent electrode of an organic EL element. The optical length of the interval between the upper surface of the semi-transmissive film and the lower surface of a counter electrode serving as a reflective layer is configured such that this interval functions as a microresonator for selecting light having a specific wavelength. Further, a light-shielding film is provided in a position corresponding to the peripheral portion of the semi-transmissive film, so as to prevent light having a different color from being ejected due to non-uniformity in the optical length.