For the application of moth-eye patterns to practical optical devices, a novel nano-patterning technique, which can fabricate transparent and robust material based nano patterns through a simple process, needs to be developed, because the moth-eye structures are usually exposed to the outer environment. In this study, silica based moth-eye structures were directly fabricated on a glass substrate by the direct hydrogen silsesquioxane (HSQ) printing and annealing technique. The transmittance of the glass substrate was enhanced by 3-4% in the visible range by the silica moth-eye structures and it was confirmed that the light output efficiency of the green organic-light emitting diode (OLED) was enhanced by 7-9% using the encapsulation glass with the silica moth-eye patterns. (C) 2011 The Electrochemical Society. [DOI: 10.1149/1.3568880] All rights reserved.