A flat fluorescent lamp includes a first substrate, a second substrate, an
external electrode, and a radiating member. The second substrate is
combined with the first substrate to form a plurality of discharge
spaces. The external electrode is formed on at least one surface of the
first substrate and the second substrate, wherein the external electrode
extends perpendicularly to the discharge spaces. The radiating member is
formed on the external electrode and radiates heat generated from the
external electrode. Therefore, the heat generated from the flat
fluorescent lamp is radiated to outside the flat fluorescent lamp through
the radiating member, reducing pinhole formation and generally improving
luminance characteristics of the flat fluorescent lamp.