Abstract: A surface light source includes a plate type light source body having a sealed discharging space formed therein, a plate type electrode unit having a plurality of regions adjacent to at least one major surface of the light source body, and a multiple voltage applying unit operable to apply voltages independently to each of the plurality of regions. In this way, brightness of the surface light source can be controlled independently in each of the plurality of regions and a local dimming for a surface light source can be realized.

Abstract: There is provided a surface light source device comprising: a light source body including a plurality of discharge spaces therein, a first electrode and a second electrode applying a first voltage into the discharge spaces and arranged parallel to each other, and a third electrode applying a second voltage into the discharge spaces and facing the first and second electrodes and arranged in a direction of crossing the first and second electrodes. In accordance with the present invention, the discharge firing voltage and sustain voltage of the surface light source device can be lowered by applying the first and second voltage to the electrodes. Further, it is possible to divisionally drive the surface light source device by sequentially and/or selectively applying a voltage to divided parts of each electrode.

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 is provided a flat electrode for a surface light source, in which a conductive electrode is formed in a fine strip-shaped pattern on a plane. The flat electrode may comprise a base layer, an electrode pattern formed on the base layer, and a protection layer formed on the electrode pattern. There is also provided an ultra thin surface light source device which comprises: a first substrate and a second substrate which are spaced apart from each other at a predetermined interval; and a first surface electrode formed on the first substrate, and a second surface electrode formed on the second substrate. The surface light source device may further comprise a medium layer formed in at least one of spaces between the first substrate and the first surface electrode and between the second substrate and the second surface electrode.