Abstract: A flat light source including a first substrate, ribs, a phosphor layer, a second substrate, electrode patterns and an insulating layer is provided. The ribs are disposed on the first substrate. The phosphor layer is disposed on the surface of the ribs. The second substrate is located above the first substrate. The electrode patterns are disposed on the second substrate, and each electrode pattern is aligned to one of the rib correspondingly. The insulating layer covers the surface of the electrode patterns. In particular, an inert gas is filled between the first and second substrates, and a discharge path is formed between the adjacent electrode patterns above the phosphor layer.

Abstract: A planar light source having a first substrate, a plurality of electrode modules, a second substrate, a dielectric spacer, a first phosphor layer, and a discharge gas is provided. The electrode modules are disposed on the first substrate. The second substrate is disposed above the first substrate. The dielectric spacer covers the electrode modules and is connected between the first substrate and the second substrate. The space between the first substrate and the second substrate is divided into a plurality of discharge spaces by the dielectric spacer. The first phosphor layer is disposed in the discharge spaces. The discharge gas is disposed in the discharge spaces. The coating area of the phosphor layer can be increased and cracks in the substrate can be prevented due to the simple structure of the planar light source.