Abstract: A sensor for measuring gas permeability of a test material, comprising: an electrically conductive sensing element that comprises a water and/or oxygen sensitive material, wherein the reaction of said material with water or oxygen when the sensing element is contacted with water and/or oxygen results in a change in the electrical conductivity of the sensing element, and two electrodes electrically connected to the sensing element.

Abstract: An Organic Light Emitting Diode (OLED) which is adapted to inhibit the formation and growth of non-emissive areas known as “dark spots.” The OLED comprises an anode disposed on a substrate, a cathode, an electroluminescent (EL) layer disposed between the anode and the cathode and a hole transport layer disposed between the anode and the EL layer. The OLED has one or more dielectric organic barrier layers disposed between one or more of the OLED's layers. These barrier layers are made from an organic polymer and are adapted to resist permeation by oxygen and moisture and to inhibit metal migration.