GLASS SUBSTRATE, ORGANIC EL ILLUMINATING APPARATUS, AND METHOD FOR MANUFACTURING GLASS SUBSTRATE

摘要

PROBLEM TO BE SOLVED: To provide a glass substrate for organic EL devices, which can be manufactured with high productivity and which enables the improvement of a light extraction efficiency.SOLUTION: A glass substrate, which can make a light-extraction side transparent substrate of an organic EL device, has a refraction index λd of 1.60 or larger. The glass substrate comprises 10-20 mol% of NaO+KO as a glass component, and has an uneven structure formed by die forming on a light-extraction side surface.