Abstract: A surface treatment layer containing alkali metal oxide is formed on at least one of substrates to form a body of a surface light source. The surface treatment layer may be formed of oxide by coating at least one of cesium, potassium, rubidium, and compound thereof on the surface of the substrate and by performing heat treatment to the substrate. The surface treatment layer containing alkali metal oxide easily emits secondary electrons and reduces firing voltage of the surface light source. Black start is improved, discharging efficiency is increased, and heat generated during the operation is decreased.

Abstract: There are provided an yttrium oxide composition having particle size of 25 nm or less, a method of preparing the same and a method of forming an yttrium oxide layer using the same. The yttrium oxide composition is prepared by dissolving an yttrium salt into a solvent to prepare an yttrium salt solution, and adding a basic compound to the yttrium salt solution to adjust a pH value to a range of 3.7 to 7. The yttrium oxide composition can form an yttrium oxide layer having improved properties since the composition has particle size of 25 nm or less and uniform particle distribution.

Abstract: The present invention relates to a product, comprising a body which is delimited by a surface, of a lithium aluminosilicate-based glass-ceramic, as well as to its method of preparation. Characteristically, said glass-ceramic has, on at least one part of said surface, a surface layer the degree of crystallization of which is greater than that of said glass-ceramic within said body.