The lifetimes of organic light emitting diodes (OLEDs) have been Successfully enhanced with the modulation of LiF thickness mid the utilization of encapsulating adhesives, which have been successfully and synthesized with UV irradiation. Experimental results demonstrate that LiF and lab-made encapsulating adhesives can block the invasion of moisture as well as oxygen in the atmosphere into the OLEDs so that the lifetimes of devices with their encapsulation are 18-folds longer than those without encapsulation. (c) 2008 Elsevier B.V. All rights reserved.