Abstract: A surface light source device includes a lamp body, a space dividing member, a discharge gas supplying member and a voltage applying part. The lamp body includes a flat shaped space and a fluorescent layer disposed in the flat shaped space to convert an invisible light into a visible light. The space dividing member divides the flat shaped space into a plurality of discharge spaces. The discharge gas supplying member is disposed to pass through the space dividing member and is fixed to the space dividing member, and supplies the discharge spaces with a discharge gas that generates the invisible light. The voltage applying part applies a discharge voltage to the discharge gas. Therefore, the lifetime of the surface light source device generating a planar light is increased, and the luminance of the light becomes uniform so that the display quality of an image is improved.

Abstract: There is provided a surface light source device comprising upper and lower substrates adhered to each other in order to form a discharge space, a reflection layer and a lower fluorescent layer stacked on an upper surface of the lower substrate, and an upper fluorescent layer stacked on a lower surface of the upper substrate, wherein the reflection layer has a thickness of 40 to 120 ?m, the lower fluorescent layer has a thickness of 10 to 60 ?m, and the upper fluorescent layer has a thickness of 10 to 25 ?m, and the device further comprises a first ion shield layer interposed between the upper substrate and the upper fluorescent layer, for blocking Na+ ions from being eluted from the upper substrate.

Abstract: Provided are a surface light source device and a backlight unit having the same. The surface light source device includes a main body with a plurality of lighting parts, and at least one electrode disposed on the lighting parts for discharging, said electrode being shaped in a partially different dimension depending the temperature difference(?t) in the lighting parts. The electrode compensates brightness uniformity lowering below a predetermined value due to the temperature difference(?t).